SEMINARS

SPRING 2009

Thursday, February 5
Location: 2237 French Family Science Center
4:30-5:45 pm

Biogeochemical models and paleoceanography: iron fertilization and ocean circulation
Payal Parekh
International Rivers (Berkeley, CA)

A coarse resolution ocean biogeochemical model (Bern3D) is used to explore two paleoceanographic issues: (a) Iron fertilization during Antarctic warm events A1 to A4, and (b) constraining ocean circulation with geochemical tracers. In the first case, the non-sea-salt calcium record from Dome C ice core, Antarctica, is used to scale aeolian iron deposition in the Southern Ocean in transient simulations over four Antarctic warm events of the last glacial period. Changes in dust flux to the Southern Ocean played a limited role in modulation of CO₂ variations. The impact of iron fluxes on CO₂ is dependent on parameter values chosen for the iron-binding ligand. In the second case, the Kalman filtering technique is applied to constrain ocean circulation during the LGM based on Cd/Ca and δ13C data. Initial results and the problems associated with such a technique will be presented.

Payal Parekh finished her PhD in 2003 in chemical oceanography in the MIT/Woods Hole Joint Program. For her thesis work, she developed a model of iron cycling that has been implemented in ocean biogeochemical models. In 2005, she received a Marie Curie Fellowship to work at the University of Bern in Switzerland with Thomas Stocker and Fortunat Joos. There she focused on using paleoclimate data (ice core and sedimentary) to guide biogeochemical models. As of October 2008, Dr. Parekh is working as a climate campaigner for the non-governmental organization, International Rivers, in Berkeley, California.

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Thursday, March 19
Location: A158 LSRC
4:15-5:30 pm

Climate change mitigation through ecosystem management
Gordon Bonan
Senior Scientist, National Center for Atmospheric Research

Climate models have long represented vegetation-atmosphere interactions in terms of radiative transfer, turbulent fluxes, and the hydrologic cycle. These models have expanded beyond their hydrometeorological roots to include terrestrial ecosystems, the carbon cycle, and vegetation dynamics. Model experiments reveal that terrestrial ecosystems provide important climate forcing and feedback, and the models are being applied to inform land management policies that can mitigate climate change. Terrestrial ecosystems influence climate through physical, chemical, and biological processes that affect planetary energetics, the hydrologic cycle, and atmospheric composition. Biogeophysical processes (albedo, evapotranspiration) are generally thought to cool climate (negative climate forcing) while biogeochemical processes (carbon) are thought to provide positive climate feedback. The net effect of these processes is highly uncertain and varies among boreal, temperate, and tropical forests. Assessment of the state of the science, current modeling capabilities, and scientific uncertainties highlights an important dilemma for simulations of historical and future climate proposed for the next IPCC (AR5) assessment report: land cover change can be regionally significant relative to other anthropogenic climate forcings, but the uncertainty in the land use forcing is large. Interdisciplinary science that integrates knowledge of the many interacting climate services of ecosystems with the impacts of global change is necessary to identify and understand ecosystem feedbacks in the Earth system and the potential of ecosystems to mitigate climate change.

Gordon Bonan is a senior scientist and head of the Terrestrial Sciences Section in the Climate and Global Dynamics Division at the National Center for Atmospheric Research (Boulder, Colorado). Trained as an ecologist, he has studied the interactions of terrestrial ecosystems with climate for over 20 years. His research integrates ecological, hydrological, and atmospheric sciences to examine natural and human changes in land cover and ecosystem functions and their effects on climate, water resources, and biogeochemistry. He has served on the editorial boards of various atmospheric and ecological journals, including editor of Journal of Climate (1998-2003). He has served on various national boards including the Climate Research Committee (2001-2003) and the Community Climate System Model (CCSM) Scientific Steering Committee (2003-2009). He has led the CCSM land model working group and its development of the Community Land Model (1997-2006) and currently leads the CCSM biogeochemistry working group. He graduated with a BA in environmental sciences from the University of Virginia in 1982 and received a MS in forest resources from the University of Georgia in 1984. He received a PhD in environmental sciences from the University of Virginia in 1988 and has been at NCAR since 1989.

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Thursday, April 2
Location: 2237 French Family Science Center
4:30 - 5:45 pm

The essential role of time and space in ecological understanding
Alan Hastings
Distinguished Professor of Environmental Science and Policy
University of California, Davis

Much of ecological thinking, and especially ecological theory, has focused on long term, or asymptotic, outcomes. Yet, in order to develop an ecological understanding of the impact of global change it will be necessary to focus on a variety of time scales. I will develop ways that time (and necessarily space) scales enter into ecological understanding, and how ecological dynamics plays out over intermediate time and space scales. I will illustrate the concepts with examples drawn from variety of ecological systems ranging from diseases to marine systems including coral reefs and many others. I will illustrate how these concepts can enter into management approaches.

Alan Hastings is a Distinguished Professor in the Department of Environmental Science and Policy at the University of California, Davis. He has research interests in a variety of areas broadly encompassing ecological theory, ranging from the study of invasive species to the dynamics of marine populations to questions related to marine protected areas. He also has been doing experimental work with flour beetles to look at spatial population dynamics. He is the author of over 200 publications. Alan received his B.A. in mathematics and his Ph.D. in applied mathematics from Cornell studying with Simon Levin and focusing on ecological questions. He was a faculty member at Washington State University in Pullman from 1977-1979 and has been at the University of California, Davis, since. He served as President of the Society for Mathematical Biology, as co-Editor in Chief of the Journal of Mathematical Biology for 13 years, and is currently the Editor in Chief of the new journal, Theoretical Ecology. He was the UC Davis Faculty Research Lecturer in 2007, is a member of the American Academy of Arts and Sciences, and received the Robert H. MacArthur Award from the Ecological Society of America in 2006.

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Thursday, April 9
Location: 2237 French
4:15 - 5:30 pm

Biological invasions as global change: patterns, processes and impacts
Tony Ricciardi
Associate Professor / Invasive Species Biologist
Redpath Museum
McGill University

Biological invasions (the spread and establishment of species into new regions) have pervaded the history of life and have periodically occurred in waves after geographic barriers had been lifted, but such events differ markedly from human-assisted invasions in spatial and temporal scales and in the diversity of organisms involved in long-distance dispersal. The role of humans as dispersers and cultivators of nonindigenous species has been profound enough to surpass natural forces of selection and dispersal. Currently, every region of the planet is affected and modern rates of invasion are several orders of magnitude higher than prehistoric rates. Prehistoric examples of biotic interchanges have increased our understanding of species-area effects, evolutionary effects, biotic resistance to invasion, and the impacts of novel functional groups introduced to naïve biotas. However, they provide only limited insight into the synergistic effects of invasions and other environmental stressors, the effect of frequent introductions of large numbers of propagules, and global homogenization, all of which characterize modern invasions. In terms of its rate and geographical extent, its potential for synergistic disruption and the scope of its evolutionary consequences, the current mass invasion event is an unprecedented form of global change.

Dr. Anthony Ricciardi is an associate professor of biology at McGill University (Montreal, Canada), where he holds a Quebec Strategic Professorship and teaches courses on animal diversity, global change, and invasion ecology. His research examines the causes and consequences of invasions, focusing on the ecological impacts of non-native aquatic organisms. He is an associate editor for the journal Diversity and Distributions, and a member of the scientific committee of the Canadian Aquatic Invasive Species Network – a research group that assesses the risks and mechanisms of invasion in Canada's lakes, rivers and coastal waters.

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Monday, April 13
Location: A247 LSRC
4:30 - 5:45 pm

Price caps and price floors in climate policy: a quantitative assessment
Cédric Philibert
International Energy Agency (Paris, France)

Co-sponsored with the Nicholas Institute's Environmental Institutions Seminar series.

This study assesses the long-term economic and environmental effects of introducing price caps and price floors in hypothetical climate change mitigation architecture, which aims to reduce global energy-related CO2 emissions by 50% by 2050. Based on abatement costs in IPCC and IEA reports, this quantitative analysis confirms what qualitative analyses have already suggested: introducing price caps could significantly reduce economic uncertainty. This uncertainty stems primarily from unpredictable economic growth and energy prices, and ultimately unabated emission trends. In addition, the development of abatement technologies is uncertain.

With price caps, the expected costs could be reduced by about 50% and the uncertainty on economic costs could be one order of magnitude lower. Reducing economic uncertainties may spur the adoption of more ambitious policies by helping to alleviate policy makers' concerns of economic risks. Meanwhile, price floors would reduce the level of emissions beyond the objective if the abatement costs ended up lower than forecasted.

If caps and floors are commensurate with the ambition of the policy pursued and combined with slightly tightened emission objectives, climatic results could be on average similar to those achieved with "straight" objectives (i.e. with no cost-containment mechanism).

A former science journalist, Cédric Philibert, born in 1954, advised the French environment minister 1988 - 1990. In 1990 he published two books on climate change and on renewable energies. From 1992 to 1998 he advised the CEO of the French Agency for the Environment and Energy Efficiency, then joined UNEP and, in 2000, the IEA, in charge of the "evolution of climate policy". In 2002 he published with Jonathan Pershing the IEA's "Beyond Kyoto" book. In 2005 he co-authored with Richard Baron the IEA's publication "Act Locally Trade Globally". Since 2007, he also teaches Energy Policy at Sciences-Po Paris. Qualified in political sciences, he studied economics and published numerous papers in peer-reviewed and other journals. Married, he has three children.

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Monday, April 27
Location: A158 LSRC
12:00 - 1:00 pm

Coal power and CO₂ capture: technologies and design status
Jeffrey Phillips
Senior Program Manager, Electric Power Research Institute (EPRI)

Jeffrey Phillips is a Senior Program Manager at the Electric Power Research Institute (EPRI). He is responsible for EPRI’s advanced generation research activities including the CoalFleet for Tomorrow® program which is focused on deploying advanced coal-based power plants that include CO₂ capture as well as EPRI’s Renewable Energy Generation program and its Generation Planning programs. Dr. Phillips began his involvement with the Institute in graduate school, providing support to an EPRI-sponsored project as part of his PhD research. He joined EPRI’s CoalFleet program in 2004 after working for 18 years on coal gasification and combined-cycle projects. Before joining EPRI, Dr. Phillips worked for the Royal Dutch/Shell group for ten years where he provided technical support to Shell’s 250 ton/day coal gasification demonstration plant in Texas and was part of the start-up team for a 250 MW IGCC in the Netherlands. He then worked as a researcher at Molten Metal Technology where he conducted tests on gasifying hazardous wastes. Later he joined Fern Engineering as a vice president and engineering consultant specializing in performance monitoring of combined cycle power plants. Dr. Phillips holds a Bachelor of Arts degree in mathematics from Austin College in Sherman, Texas and a Bachelor of Science degree in mechanical engineering from Washington University in St. Louis, Missouri. He also holds a Master of Science degree and doctorate from Stanford University in Palo Alto, California, also in mechanical engineering.

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Monday, May 18
Location: A247 LSRC
12:00 - 1:00 pm

Stockholm to Earth Summit 2012 — the emergence of stakeholder democracy
Felix Dodds
Executive Director, Stakeholder Forum for a Sustainable Future

The first UN Conference on Environment in 1972 was influenced considerably by what was then generally termed non-governmental organizations. It started a relationship between what is now more commonly termed stakeholders and international environmental and sustainable development multilateral agreements. In Dick Morris’s book 'The New Prince,' he argues we are moving from Madisonian Democracy (representative) to Jeffersonian Democracy (participatory). Felix will argue that we are in a phase of stakeholder democracy.

What will be looked at is what role in some of these processes stakeholders have played and what role they are now taking in preparations for a new Summit in 2012.

Felix Dodds is the Executive Director of Stakeholder Forum for a Sustainable Future. He has been active at the UN since 1990 attending the World Summits Rio, Habitat II, Rio+5, Beijing+5, Copenhagen+5, WSSD. He has also been to all the UN Commissions for Sustainable Development and UNEP Governing Council. He has set up three global NGO coalitions for UN Conferences, Summits and Commissions - these are the UN Commission on Sustainable Development (1993), the UN Habitat II (1995) the WHO Health and Environment Conference (1999). He co-chaired the NGO Coalition at the UN Commission on Sustainable Development from 1997 to 2001. He introduced Stakeholder Dialogues in 1996 through the UN General Assembly for Rio+5 and helped run some of the most successful ones at Bonn Water (2001) and Bonn Energy (2004). He has written or edited several books including Human and Environmental Security - An Agenda for Change (nominated for the best environmental book of 2005).

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FALL 2008

Friday, Sept 5
French Family Science Center, room 2237
1:15-2:30 pm

Terrestrial sources and sinks of carbon and climate change
Richard Houghton
Senior Scientist, Woods Hole Research Center

Co-sponsored with the University Program in Ecology seminar series.

Terrestrial sources and sinks of carbon are difficult to measure over the surface of the earth at any scale. In fact, terrestrial ecosystems appear twice in the global carbon budget. First, they are a (net) source of carbon from land-use change (including both deforestation, reforestation, and afforestation), accounting for about 20% of total anthropogenic emissions. And, second, they are also a (net) carbon sink that offsets approximately 30% of total anthropogenic emissions. This terrestrial sink is determined by difference: the sink is needed to balance total emissions of carbon (from fossil fuels and land-use change) with total 'known' sinks (atmosphere and oceans). Errors in any of these four terms directly affect the magnitude of this 'residual' terrestrial carbon sink. The sink has never been measured globally, and its magnitude, location, and causes are unknown. Most ecologists have assumed that the terrestrial carbon sink is the result of physiological responses to environmental changes (e.g., increased CO₂, increased N availability, climatic change), but a major portion of it may be the result of changes in forest age structure as a result of past disturbances (both natural and human-induced) and continuing recovery (carbon accumulation).

Understanding the causes of this residual terrestrial sink is important for predicting future climate. There is no guarantee that the sink will continue. Has it already begun to change? A key global indicator of a change in this annual carbon sink is the airborne fraction: the fraction of total anthropogenic carbon emissions (fossil fuels and land-use change) that remains in the atmosphere. The long-term airborne fraction has been remarkably constant over the last 50 years, but there is recent evidence for an increase; i.e., the annual carbon sink in terrestrial ecosystems may be declining.

Dr. Richard A. Houghton is Deputy Director and Senior Scientist at the Woods Hole Research Center in Falmouth, Massachusetts. The Center in as independent, nonprofit institute focused on environmental science, policy, and education. Trained as an ecologist, Dr. Houghton has studied the interactions of terrestrial ecosystems with the global carbon cycle and climate change for nearly 30 years. His area of expertise has been documentation of changes in land use and determination of historic and current sources and sinks of carbon resulting directly from human activity. He has participated the IPCC Assessments of Climate Change and the IPCC Special Report on Land Use, Land Use Change, and Forestry. Dr. Houghton received a Ph.D. in ecology from the State University of New York at Stony Brook in 1979 and has worked as a research scientist at Brookhaven National Laboratory in New York and the Marine Biological Laboratory in Woods Hole, Massachusetts. He has been at the Woods Hole Research Center since 1987, serving for two years (1993-1994) as a visiting senior scientist at NASA headquarters in Washington, D.C.

Friday, October 10
French Family Science Center, room 2237
1:15-2:30 pm

Permafrost carbon and climate feedbacks in a warmer world
Ted Schuur
Assistant Professor of Ecosystem Ecology, Department of Botany, University of Florida

Co-sponsored with the University Program in Ecology seminar series.

At least 1218 Pg (billion tons) of soil carbon (C) are stored in permafrost soils in boreal and arctic ecosystems, almost twice as much C than currently contained in the atmosphere. Permafrost thaw, and the microbial decomposition of previously frozen organic C, is considered one of the most likely positive feedbacks from terrestrial ecosystems to the atmosphere in a warmer world. Yet, the rate of release is highly uncertain but crucial for predicting the strength and timing of this C cycle feedback, and thus how important permafrost thaw will be for climate change this century and beyond. We report results from a tundra landscape undergoing permafrost thaw, where net ecosystem C exchange and the radiocarbon age of ecosystem respiration were measured to determine the influence of old C loss on ecosystem C balance. Sustained transfers of C to the atmosphere that could cause a significant positive feedback to climate change must come from old C, which forms the bulk of the permafrost C pool that accumulated over thousands of years. Areas that thawed over the past 15 years had 75% more annual losses of old C compared to minimally thawed areas, but had overall net ecosystem C uptake as increased plant growth offset these losses. In contrast, sites that thawed decades earlier lost an additional 25% more old C annually, which contributed to overall net ecosystem C release despite increased plant growth. These data document significant losses of soil C with permafrost thaw that, over decadal time scales, overwhelms increased plant C uptake at rates that could make permafrost a large biospheric C source in a warmer world, similar in magnitude to current C fluxes from land use change.

Ted Schuur is an Associate Professor in the Department of Botany at the University of Florida as well as a Research Associate in the Institute for Arctic Biology at the University of Alaska Fairbanks. He is an ecologist who studies interactions between terrestrial carbon cycling and climate change. In particular, he uses geochemical techniques for measuring natural abundance radiocarbon in ecosystem pools and fluxes to trace the sources of carbon emissions to the atmosphere. One of his major research interests is to understand feedbacks to atmospheric CO₂ from warming temperature, thawing permafrost and changing fire regimes in high latitudes ecosystems. His work on this topic has included over a decade of research in boreal and arctic Alaska and northeastern Siberia. He has participated in national and international meetings, workshops, and panels on the topic of ecology and the environment. He has received new investigator awards from NASA and the Andrew W. Mellon Foundation for his work on carbon and nutrient cycling in terrestrial ecosystems, and a CAREER grant from the National Science Foundation for research and education centered on the use of radiocarbon in ecology and earth system science. He is a native of Michigan and graduated Magna Cum Laude with a BS from the University of Michigan in 1991. He received a PhD from the University of California-Berkeley in 1999 and held a National Science Foundation Postdoctoral Fellowship in Bioinformatics at the University of California-Irvine before arriving in Gainesville, FL in 2001.

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SPRING 2008

Thursday, Feb 28
A-158 LSRC
4:00-5:15 pm

Introduction of multi-model ensembles and downscaling for regional risk assessment of climate change
Koji Dairaku
Researcher, Storm, Flood, and Landslide Research Department, National Research Institute for Earth Science and Disaster Prevention, Japan

Co-sponsored with the Pratt School of Engineering

Climate change and the threats of extremes to human life and natural ecosystems constitute a fundamental concern. Reliable regional climate change projection and improved impact assessment sufficient for the application to impact assessment and adaptation studies are increasingly required by the policy community.

In Japan, the climate research project(S-5) has just started (FY2007-2011) for "Getting a feel for climate change". As one of the research activities, we will try downscaling study in Japan/Asian region. I would like to introduce the downscaling project and a part of our preliminary activities.

Monday, Apr 21
A-158 LSRC
4:00-5:15 pm

Strategies to coordinate economic development, energy use, and emission control in China
Ji Zou
Vice Dean, School of Environment and Natural Resources
Head, Department of Environmental Economics and Management
Renmin University of China

Serving 20% of the world population, experiencing a high, lasting growth rate in the past three decades and developing increasingly closer international trade and investment ties, the Chinese economy and its society have had, and will continue to face, environmental and energy challenges which have been both local and global concerns. This presentation begins by highlighting several key development concerns in China which are regarded as driving forces for the current and future features of the environment and energy situation in China. Then it will consider both Business-As-Usual (BAU) and Action-taking Scenarios on changes in energy use and CO2 emission, based on modeling exercises and latest estimations of some different parameters in order to predict the potentials of emission reduction and energy saving. This presentation assumes that technology changes in the coming decades in China may lead to significant emission reduction against BAU scenario, and thus the final solution for both global warming and local environmental quality improvement. Based on this assumption, the presentation assesses several technological options in such energy/emission intensive sectors as power, transport, housing, cement, ferrous and non-ferrous metallurgy, chemical products, and petroleum refining in terms of emission reduction of GHGs and local pollutants, cost, and maturity of technologies. Finally, this presentation will explore a framework for integrating the strategic and policy objectives from three dimensions of development: energy, global warming, and local environmental concerns. Possible directions and further work based on this discussion will be identified.

Professor Zou was awarded a B.S. in environmental engineering (1984), an M.S. in Engineering Economics (1990) at Tsinghua University, and a Ph.D. in environmental and resources economics (1997) at RUC. He was a visiting scholar for London School of Economics and Political Sciences in 1995~1996, Resources for the Future in 1995, and John F. Kennedy School of Government at Harvard University in 2007. Professor Zou has worked in such areas as energy and climate policies with technology changes as focus, and sustainable urban planning. He has been nominated as a delegate of China for UN Climate Talks since 2000 and worked as a lead author of Working Group III of IPCC. In 2007, he and his team joined a research on Economics of Win-Win Energy Policies in China sponsored by The William and Flora Hewlett Foundation and in cooperation with Woods Hole Research Center.

At this time, Professor Zou is leading a study on China's national strategy on energy and greenhouse gases control jointly sponsored by State Environmental Protection Administration (SEPA, now Ministry of Environment) and Chinese Academy of Engineering (CAE). He is also working on the design of China's proposal on technological cooperation in the context of international regime of climate beyond 2012.

Thursday, Apr 24
A-158 LSRC
3:30-4:30 pm
(come early for refreshments at 3:00-3:30)

Hydrology in an era of global change
Dennis Lettenmaier
Professor, Department of Civil and Environmental Engineering, University of Washington, Hydrology Surface Water Hydrology Research Group

Water is essential for human life. Since the earliest civilizations, man has attempted to provide stable and secure sources of freshwater. This quest has dealt, until quite recently, with attempting to buffer the effects of what is often termed "natural variability" in the land surface branch of the water cycle, and especially streamflow. We now face challenges that require that we recognize that the realm of "natural variability" in the water cycle both affects, and is affected by, man's activities, through at least three agents of change. The first is land cover and land use - much of the global land surface has now been affected by man's activities. Examples include growth of agriculture, harvest and management of forests (including fire suppression), and growth of urban areas, among others. The second agent of change is climate - it is now increasingly apparent that man's activities have and will continue to change the water cycle. The third is water management - construction of impoundments and withdrawals for consumptive and other uses, as well as diversion of major rivers, increasingly has altered the land surface, and perhaps atmospheric, water cycles. I discuss examples of these three agents of change both in the U.S. and internationally, and outline some of the scientific challenges in predicting water cycle variations that go beyond the traditional hydrologic view of characterizing natural variability.

Dennis Lettenmaier received his B.S. in Mechanical Engineering (summa cum laude) at the University of Washington in 1971, his M.S. in Civil, Mechanical, and Environmental Engineering at the George Washington University in 1973, and his Ph.D. at the University of Washington in 1975. He joined the University of Washington faculty in 1976. In addition to his service at the University of Washington, he spent a year as visiting scientist at the U.S. Geological Survey in Reston, VA (1985-86) and was the Program Manager of NASA's Land Surface Hydrology Program at NASA Headquarters in 1997-98. He is a member of the American Geophysical Union, the American Water Resources Association, the American Meteorological Society, and the American Society of Civil Engineers. He was a recipient of ASCE's Huber Research Prize in 1990, and the American Geophysical Union's Hydrology Section Award in 2000. He is a Fellow of the American Geophysical Union and American Meteorological Society, and is the author of over 100 journal articles. He was the first Chief Editor of the American Meteorological Society Journal of Hydrometeorology, and is currently an Associate Editor of Water Resources Research. His areas of research interest are large scale hydrology, hydrologic aspects of remote sensing, and hydrology-climate interactions.

Wednesday, May 7
A-158 LSRC
3:00-4:15 pm
(light refreshments at 2:30-3:00)

Energy and environmental policies in India
Leena Srivastava
Executive Director of The Energy and Resources Institute (TERI), India

Dr Leena Srivastava is Executive Director, TERI and Senior Vice President of TERI-NA (The Energy and Resources Institute, North America), Washington, DC, USA. She has been the Dean, Faculty of Policy and Planning, TERI University, since June 2000 and she teaches doctoral courses in Energy Policy and Planning and Infrastructure Economics, and she was the Vice-President, TERI-NA from November 1992 to January 1994.  Dr. Srivastava has a number of publications to her credit and is on the editorial boards of several international journals dealing issues related to energy and the environment.  She serves on the Research Advisory Committee of IGES (the Institute for Global Environmental Strategies, Japan), the International Advisory Board of the Wuppertal Institute for Climate, Environment and Energy, Germany and is a member of the Scientific Steering Committee of the IHDP-IT Programme (International Human Dimensions Programme - Industrial Transformation). She was the member of the Expert Committee to formulate Energy Policy set up by the Planning Commission, Government of India, and was a Coordinating Lead Author for Working Group III of the Third Assessment Report of the IPCC (Intergovernmental Panel on Climate Change). Dr. Srivastava is currently the Anchor for Sustainable Development and Climate Change for the Fourth Assessment Report.

Wednesday, May 21
A-247 LSRC
12:00-1:15 pm

Organizing carbon capture and storage deployment: Returns to scale for the coupled technological system
Jeff M. Bielicki
Public Policy Ph.D. student, Harvard University, and Research Fellow with the Energy Technology Innovation Policy Project at the Belfer Center for Science and International Affairs, Harvard Kennedy School of Government

Jeff will present his work-in-progress on the returns to scale for CCS deployment. He will introduce an innovation in geospatial optimization methodology for infrastructure planning and deployment, the interaction of the returns to scale for each technological component of the CCS system and for the entire system, and a number of policy relevant questions such as the choice of where within a potential storage basin to focus on site-specific reservoir characterization, where to locate injection sites, and where to place trunk distribution pipelines.

Carbon capture and storage (CCS) has the potential to dramatically reduce the atmospheric accumulation of carbon dioxide (CO2) emitted from human activities while simultaneously serving as a bridging technology to less fossil-dependent energy systems. To do so, a system of interlinked technologies that captures CO2 from sources and transports it to geologic storage reservoirs into which the captured CO2 is injected must be deployed at a considerable scale. This technological coupling determines the returns to scale for the entire carbon capture and storage system and suggests how, given the spatial distribution of sources and potential reservoirs, CCS activities should be organized.

Jeff will present his work-in-progress on understanding the returns to scale for CCS deployment. The talk will introduce an innovation in geospatial optimization methodology for infrastructure planning and deployment, the interaction of the returns to scale for each technological component of the CCS system and how they couple together to determine the returns to scale for the entire system, and a number of policy relevant questions such as the choice of where within a potential storage basin to focus on site-specific reservoir characterization, where to locate injection sites, and where to place trunk distribution pipelines.

Jeff Bielicki is a research fellow with the Energy Technology Innovation Policy Project at the Belfer Center for Science and International Affairs at the Harvard Kennedy School of Government, where he is also a PhD student in public policy. Jeff researches technological innovation and deployment at the nexus of engineering, environmental, and social systems. He is currently focusing on a number of issues pertaining to the scale and implications of the deployment of carbon capture and storage (CCS) as it couples the organization of CO2-emitting sources with the organization of amenable CO2 storage geology. His recent work includes the impact of CCS on the location of electric power generation, the viability of permanent CO2 storage in deep sea sediment, and the returns to scale for CCS. Before coming to Harvard, Jeff was a mechanical engineer at Fermi National Accelerator Laboratory (outside Chicago, Ill.) and the University of Rochester University for Laser Energetics (Rochester, N.Y.). He has published pieces on solar energy and antiproton production. Through his participation in the Young Scientists Summer Program, Jeff was a member of the Transitions to New Technologies program at the International Institute for Systems Analysis (IIASA). He was also a Santa Fe Institute research scholar at the complex systems summer school, and a Crump Fellow. He holds a BSME (Valparaiso University), an MBA (University of Chicago), and an MPA (Harvard University). He is a member of Tau Beta Pi (engineering honor society), Sigma Xi (scientific research society), the American Society for Mechanical Engineers, the American Economic Association, and the Society for Industrial and Applied Mathematics. Jeff is an improvisational comedian, a baseball player, and a student of Tae Kwon Do.

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FALL 2007

Friday, Sept 14
Levine Science Research Center, room B101
11:40 am

Recent Trends in Terrestrial Water Storage from the GRACE Mission
Jay Famiglietti
Department of Earth System Science, University of California, Irvine

Co-sponsored with the Water Forum seminar series.

The Gravity Recovery and Climate Experiment (GRACE) satellite mission offers a new opportunity to monitor changes in total water storage (combined snow, surface water, soil moisture and groundwater) from the large river basin (>200,000 km²) to the global scale, and at monthly and longer timescales. In this presentation I will explain how the GRACE satellites can provide hydrologic information on water storage anomalies and storage changes, as well as the implications for terrestrial and global hydrology. These include new information on spatial and temporal variations in water storage changes, the emergence of short-term trends in storage, and water balance closure at multiple scales. Examples of recent work on GRACE-based estimates of regional and global discharge, groundwater storage changes and mass changes in Earth’s land, ocean and ice reservoirs will be presented.

Prof. Jay Famiglietti is a hydrologist on the faculty in the UCI Department of Earth System Science and holds a joint appointment in Civil and Environmental Engineering. He teaches courses in terrestrial and global hydrology, as well as introductory Earth System Science. His research group uses satellite remote sensing to track water availability on land and has been working for many years towards improving hydrological prediction in global climate models. Before joining the faculty at UCI in 2001, Prof. Famiglietti was an Assistant and Associate Professor in the Department of Geological Sciences at the University of Texas at Austin, and was the Associate Director of the UT Environmental Science Institute. Prof. Famiglietti currently serves as the Editor-in-Chief for the journal Geophysical Research Letters. He is also serves on the Executive Committee of CUAHSI, the Consortium for the Advancement of Hydrological Sciences, Inc.

Prof. Famiglietti holds a B.S. in Geology from Tufts University, an M.S. in Hydrology from the University of Arizona, and an M.A. and a Ph.D. in Civil Engineering from Princeton University. He completed his postdoctoral studies in hydrology and climate system modeling at Princeton and at the National Center for Atmospheric Research.

Wednesday, Sept 26
Fitzpatrick Center (CIEMAS), Schiciano Auditorium (Side B)
12:30-1:30

Toward the characterization of snowpack from space-borne satellite measurements: A multi-frequency multi-scale data assimilation approach
Steve Margulis
Department of Civil and Environmental Engineering, University of California, Los Angeles

Co-sponsored with the Civil and Environmental Engineering seminar series.

The cryosphere represents an important component of the Earth system, with 30% of the overall global land surface covered seasonally by snow (which greatly impacts surface albedo and hence surface energy partitioning) and one-sixth of the global population living in areas where streamflow is dominated by snowmelt runoff (which in some cases makes up more than 75% of the annual water supply). Hence the ability to accurately characterize the snowpack state over large regions has significant implications for weather, climate, and water resources planning. Traditionally, snow water equivalent (SWE) estimation by water agencies has been done using data from snow surveys (performed at select locations in space and periodically during the winter months) in conjunction with regressions based on the historical record. These methods can be inaccurate due to sampling problems and the fact that regression-based schemes are suspect in the context of a changing climate. In the last couple of decades researchers have begun exploring the ability to map snowpack states using space-borne remote sensing measurements. These efforts generally include techniques to either map the presence/absence of snow or retrieve the snow water equivalent. These techniques generally do not provide the desired quantity (SWE) at the necessary resolution and accuracy over large scales. Here we discuss recent work aimed at attempting to assess the feasibility of estimating snowpack characteristics in mountainous terrain by merging remote sensing data spanning the electromagnetic spectrum from the visible to the microwave with process models describing the evolution of the distributed snowpack and its associated radiative transfer. Some future implications of the work include improved lead-time water supply forecasts as well as initial conditions in seasonal climate forecasts.

Thursday, Oct 25
A-158 LSRC
4:00pm-5:15pm

Changing views of a changing Arctic: Climate, element cycling, and vegetation in northern Alaska since the 1970s
Gus Shaver
Senior Scientist, The Ecosystems Center, Marine Biological Laboratory

Perspectives on the regulation of arctic tundra ecosystems have changed dramatically over the past 35 years, as research has focused increasingly on responses to climate change and long-term controls over species composition and element cycling. Long-term experimental manipulations of temperature, light, and soil nutrients frequently lead to changes that would not be predicted from short-term studies of individual species or ecosystem processes. This talk will describe how nitrogen limitation and species composition interact to determine long-term changes in tundra carbon cycles, and feedbacks to global climate change.

Gaius (Gus) Shaver received a Ph.D. in Botany from Duke University in 1976, after completing Bachelor's and Master's degrees at Stanford in 1972. Since 1979 he has worked at The Ecosystems Center of the Marine Biological Laboratory, in Woods Hole, Massachusetts, where he is now a Senior Scientist. Gus was introduced to the Arctic while a graduate student at Duke, where he completed a dissertation on root growth in cold, wet, tundra soils under the supervision of W.D. Billings. Since leaving Duke most of his research has focused on arctic ecosystems and on the role of plants in tundra element cycles. This work includes the analysis of responses to long-term field experiments at the Arctic LTER site at Toolik Lake, Alaska, the development of models of multiple resource limitation in vegetation and ecosystems, and a growing interest in interaction of the PanArctic region with the global climate system.

Thursday, Nov 29
A-158 LSRC
4:00pm-5:15pm

Carbon emissions from tropical deforestation: Science meets policy
Ruth DeFries
Professor, Department of Geography and Earth System Science Interdisciplinary Center, University of Maryland, College Park

Consideration of carbon credits to developing countries for averted deforestation is high on the policy agenda. The underpinnings for such policies rest on technical capabilities to estimate and monitor carbon emissions. Changing dynamics of deforestation in some parts of the tropics towards mechanized, large-scale production challenges current methods to estimate emissions. The presentation will discuss scientific uncertainties in estimating deforestation emissions and new approaches to modeling carbon fluxes using a variety of remotely-sensed data inputs. The presentation will focus on two spatial scales, a state-level effort to improve modeling capabilities to estimate deforestation fluxes and a pan-tropical effort to identify hotspots contributing disproportionately high emissions.

Ruth DeFries' research investigates the relationships among human transformation of the land surface and the biogeochemical and ecological processes that regulate the Earth's habitability. The research uses satellite imagery as a lens to examine changes in the land surface over large areas. The overall thrust of the research is to develop underlying science for balancing the needs of human society to transform the landscape for food production, settlements and other requirements while maintaining long-term habitability of the planet.

Ruth DeFries holds a PhD from Johns Hopkins University and BA summa cum laude from Washington University. She is a member of the US National Academy of Sciences and a fellow of the MacArthur Foundation and the Aldo Leopold Leadership Program.

Thursday, Dec 6
A-247 LSRC
3:00pm-4:15pm

Macroecology: Do mechanisms matter?
John Harte
Professor, Department of Environmental Science, Policy and Management, University of California, Berkeley

Maximization of information entropy, S = -SUM(p log(p)), subject to known constraints on the probability distribution p, yields the least biased, or most likely, probability distribution subject to those constraints. In statistical physics, this powerful inference method yields, under the constraint of energy and particle number conservation, classical thermodynamics. Here we apply this method to ecology, starting with logically necessary constraints formed from ratios of four state variables: total area of an ecosystem, total number of species within a taxonomic grouping, total number of individuals across those species, and total metabolic energy required by all those individuals. Entropy maximization under these constraints yields realistic expressions for all the major biodiversity metrics widely used in macroecology, including the Fisher log-series species-abundance distribution, the species-level spatial abundance distributions, the species-area relationship, the distribution of allocated metabolic energy across individuals, and if metabolic theory of ecology is assumed, the Damuth mass-abundance relationship and the energy-equivalence rule. Using plant census data for testing purposes, the theory predicts, with no adjustable parameters, the central tendencies, both within and across sites and spatial scales, of all these macroecological metrics.

John Harte is a Professor of Ecosystem Sciences at the University of California, Berkeley. Following undergraduate studies at Harvard and a doctoral degree in Physics from the University of Wisconsin, he was an NSF Postdoctoral Fellow at CERN, Geneva and an Assistant Professor of Physics at Yale. He is the recipient of a Pew Scholars Prize in Conservation and the Environment, a Guggenheim Fellowship, the 2001 Leo Szilard prize from the American Physical Society, the 2004 UC Berkeley Graduate Mentorship Award, a Miller Professorship, and is a co-recipient of the 2006 George Polk award in journalism. He is an elected Fellow of the California Academy of Sciences and the American Physical Society. He has also served on six National Academy of Sciences Committees and has authored over 180 scientific publications, including six books. One of those books, "Consider a Spherical Cow" is a widely used textbook on environmental modeling.

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SPRING 2007

Friday, Jan 12
A-247 LSRC
1:15-2:30 pm

Variability in air-sea CO₂ flux in the Ross Sea, Antarctica: An ecosystem model analysis
Kevin Arrigo
Associate Professor of Geophysics, Stanford University

Co-sponsored with the Duke University Program in Ecology

Phytoplankton dynamics, primary production, and air-sea CO₂ exchange in the Ross Sea, Antarctica over a six-year period (1997-2003) were investigated using a combination of satellite remote sensing and numerical ecosystem modeling. Sea ice cover in the Ross Sea was highly variable during this time, with three years exhibiting a normal springtime retreat of the annual sea ice and three years exhibiting very heavy ice cover, particularly 2002-03. Annual net primary production (NPP) during normal ice years ranged from 141-180 g C m^-2 yr^-1, dropping to 27.3-96.2 g C m^-2 yr^-1 during heavy ice years. The prymnesiophyte Phaeocystis antarctica was the phytoplankton taxa responsible for the bulk of the annual NPP, although diatoms increased in relative importance during heavy ice years. Reductions in surface water pCO₂ due to phytoplankton CO₂ fixation during spring and summer, and the return of the annual sea ice in the autumn and winter (thus restricting gas exchange) made the Ross Sea a net sink for atmospheric CO₂. The magnitude of the annual net flux of CO₂ (FCO₂) into the Ross Sea varied >20-fold between years, from -0.07 mol C m^-2 in 2002-03 to -1.55 mol C m^-2 in 1999-00 (negative values denote flux from air to sea). In some regions, annual FCO₂ was as high as -2.9 mol C m^-2, with daily rates approaching -62 mmol m^-2 d^-1. These results rank the Ross Sea as one of the stronger ocean sinks for atmospheric CO₂ and demonstrate the sensitivity of FCO₂ in polar waters to changes in sea ice cover.

As a biological oceanographer, my principal interest has been in the role marine microalgae play in biogeochemical cycling, with particular emphasis on the scales of temporal and spatial variability of microalgal biomass and productivity. This knowledge is essential to understanding how anthropogenic and atmospheric forcing controls the biogenic flux of CO₂ into the oceans, and ultimately, to the sediments. My research is highly interdisciplinary and incorporates three fundamental approaches, (1) satellite remote sensing, (2) ecophysiological modeling, and (3) laboratory and field studies. By combining these techniques, it is possible to address many complex aspects of ocean biogeochemistry at spatial and temporal scales that would not be possible using a single approach.

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Friday, Jan 26
A-247 LSRC
12:00-1:15 pm

What's new at the Ecological Society of America?
Clifford Duke
Director, Science Office, Ecological Society of America

In this informal seminar, Dr. Duke will discuss new science initiatives and programs at ESA.

Dr. Duke joined the Ecological Society of America (ESA) as Director of Science Programs in January 2003. The Science Office originated with ESA's Sustainable Biosphere Initiative in 1992, and focuses on the application of ecological science to environmental problem solving. To that end, the Office works with ESA members, other professional societies, and public agencies to develop workshops and publications on a variety of topics related to ecosystem sustainability, global change and biodiversity.

Before coming to ESA, Dr. Duke worked for 13 years in environmental consulting, managing preparation of environmental impact statements and ecological risk assessments for Department of Defense and Department of Energy facilities nationwide. He also contributed to a variety of transportation projects, from the environmental impact statement for the breakup of the Conrail railroad, to the planning of a bicycle trail in Washington, DC. Most recently, Dr. Duke ran the Arlington office of The Environmental Company, Inc., a firm headquartered in Charlottesville, VA.

Trained as a marine ecologist, Dr. Duke received his Ph.D. in Botany from Duke University, studying with Dr. Joseph Ramus at Duke University Marine Laboratory. Duke also obtained an M.A. in Public Policy Science from Duke University's Institute of Public Policy. Following his graduate studies, he held postdoctoral positions at Northeastern University, Wellesley College, and the Harvard School of Public Health, before moving into the consulting field. In addition to his BOSC service, Dr. Duke currently serves on the Sustainable Rangelands Roundtable and the Board of Directors of the Chesapeake Potomac Regional Chapter of the Society of Environmental Toxicology and Chemistry. He is also an active member of a number of other professional societies, including the Society for Risk Analysis and the National Association of Environmental Professionals.

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Tuesday, Feb 13
A-158 LSRC
4:00-5:15 pm

Impacts of Changing Land Use on Subsurface Water Resources in Semiarid Regions
Bridget Scanlon
Bureau of Economic Geology, Jackson School of Geosciences, University of Texas, Austin

Co-sponsored with the Department of Marine, Earth, & Atmospheric Sciences, NC State

The most widespread changes in land use have occurred because of agricultural expansion. In the past 300 years, cultivated cropland and pastureland have increased globally by 560% and 660%, respectively. Irrigated agriculture has expanded by 580% since 1900 and is projected to increase by 20% by 2030 in developing countries Agricultural food production accounts for ~85% of global fresh water consumption, led by irrigated agriculture. What impacts have these land-use changes had on water resources? Measurements of pressure head, soil pore water chemistry, groundwater levels, and groundwater quality provide an archive of system response to past land-use changes. The presentation will focus on the Texas Southern High Plains, which is one of the largest agricultural areas in the United States. Cultivation of natural grasslands has changed the system from discharging through evapotranspiration since Pleistocene times (~10,000 to 15,000 yr) to recharging during the past 50 to 100 yr. Recharge under rain-fed agriculture is shown by large groundwater-level rises (average 7 m over 3,400 km² area of rain-fed agriculture) during the last few decades, resulting in a median recharge rate of 21 mm/yr (5% of precipitation). Changes from discharge to recharge conditions reflect long fallow periods (~7 months/yr) associated with cultivation. Recharge under irrigated agriculture is shown by downward hydraulic head gradients. Large groundwater-level declines (as much as 75 m) under irrigated areas indicate that irrigated agriculture is not sustainable. Results from land-use changes in this region will be compared with those from other regions globally. Although past land-use changes had unintended impacts on the water cycle, a comprehensive understanding of these impacts could be used to alter land-use practices for better management of water resources.

Bridget Scanlon received a B.S. in Geology at Trinity College, Dublin (Ireland), an M.S. at the University of Alabama, and a Ph.D. from the University of Kentucky (Lexington). She is currently a Senior Research Scientist at the Bureau of Economic Geology, the Jackson School of Geosciences. The primary objective of her research group is to assess sustainability issues with respect to water resources, within the context of climate variability and land-use change. Studies integrate physical, chemical, and isotopic analyses and numerical modeling. Much of her research focuses on groundwater recharge in semiarid regions in natural and cultivated ecosystems. Bridget Scanlon has taught Vadose Zone Hydrology at the Dept. of Geological Sciences and Civil Engineering at UT. She participated in focus groups on global recharge issues within the IAEA. She served on NAS committees on radioactive waste disposal and is currently serving on the Integrated Observations on Hydrologic Sciences committee.

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Thursday, Mar 8
A-158 LSRC
4:00-5:15 pm

Climate Change 2007: Key findings of the Intergovernmental panel on climate change
Gabi Hegerl
Nicholas School of the Environment and Earth Sciences, Duke University

Recently, the results of Working Group 1 of the Fourth Assessment report of the Intergovernmental Panel on Climate Change have been approved and the Summary for Policymakers has been released.

This report assessed scientific findings from the last 6 years on observed climate change and predictions of future changes. It concluded that warming of the climate system is unequivocal. Based on statistical studies attributing observed changes to causes, for example, increases in greenhouse gases or natural variability, the report concluded that most of the global warming over the second half of the 20th century has very likely been due to greenhouse gas increases, and that evidence for human influences now extends to a wider range of climate variables. We now better understand the sensitivity of the climate system to radiative forcing like greenhouse gas increases, and can give a "likely" range for future global mean temperature changes for different emission paths. Projections of changes in rainfall are now highlighted in the Summary for Policymakers. However, projections of sea level rise do not account for rapid dynamical changes in ice flow, since a scientific basis for estimates is lacking.

The main area of Gabi Hegerl's research is the natural variability of climate and changes in climate due to natural and anthropogenic changes in radiative forcing (such as greenhouse warming, climate effects of volcanic eruptions and changes in solar radiation). Studying global scale surface temperature observations shows that the 20th century temperature evolution is highly unusual relative to estimates of climate variability, and that greenhouse gas forcing is likely responsible for a large fraction of the 20th century warming. Gabi and collegues are still looking into narrowing uncertainties in that assessment (such as study the effect of uncertainties in model simulations of climate change, and assess if temperature variability of the last millenium is consistent with our interpretation of climate of the 20th century). However, for society changes in more regional aspects of climate and changes in climatic extremes and rainfall have potentially a stronger impact. Gabi is therefore studying changes in climate extremes in climate model simulations and tries to detect them in observations. Other interests include detecting continental scale climate change in temperature and rainfall data, climate variability, particularly variability that influences climate on long timescales, and changes in modes of climate variability such as the Northern and Southern Annular modes (also called AO and AAO) and their influence on temperature, rainfall and climate extremes. Gabi is also involved in the preparation of the upcoming Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report as a coordinating lead author, in the CCSP report on changes in climate extremes, and serves in various committees (e. g. CLIVAR, NRC)

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Thursday, Mar 22
NESCent, 2024 W. Main Street, Suite A200
4:00 pm

Climate and plants in California: Past, present, and future
David Ackerly
Associate Professor, Department of Integrative Biology, University of California, Berkeley

Co-sponsored with the National Evolutionary Synthesis Center (NESCent)

The California Floristic Province, a global biodiversity hotspot, contains more than 5500 native plant taxa, and over half of these are endemic to the region. The flora is composed of disparate elements derived from temperate, desert and sub-tropical origins, combined with extensive diversification during the onset of the modern mediterranean-type climate. The evolution of sclerophyllous leaves among woody chaparral species has often been considered a classic case of convergent evolution, but phylogenetic analysis indicates that this trait is ancestral in many lineages, predating the onset of the current Mediterranean-type climate. Leaf and seed traits differ among taxa derived from contrasting biogeographic regions, reflecting the imprint of history on the functional diversity of the modern flora. A phylogenetic analysis of climatic niche distributions will be presented, relating modern distributions to evolutionary and biogeographic history.

With anticipated climate change, up to 69% of the endemic taxa are projected to experience reductions in range size of >80% within a century. Projected impacts depend on the magnitude of future emissions and on the ability of species to disperse. Unexpectedly, California's varied terrain could cause species to move in very different directions, breaking up present-day floras. Potential refugia, harboring species undergoing severe range reductions, are sometimes but not always coincident with areas of high diversity. Protecting future refugia and facilitating species dispersal will be essential to maintain biodiversity in the face of climate change.

David Ackerly is currently an Associate Professor in the Department of Integrative Biology at the University of California Berkeley. A native of New England, he conducted his Ph.D. and post-doctoral research at Harvard University, including fieldwork in Brazil, Mexico, New England and Japan. Prior to his current position, he was an Assistant Professor at Stanford University. Ackerly's research focuses on the ecology and evolution of plant functional traits, including canopy architecture, leaf physiology, hydraulic architecture and seed size. He is particularly interested in the integration of comparative ecology with phylogenetics and community ecology. Current projects in Ackerly's lab include studies on niche evolution and community assembly in vernal pools, variation in flammability in chaparral shrubs, and the potential impacts of climate change on the flora of California. Ackerly's teaching includes courses in Plant Ecology, Introduction to Ecology, Phylogenetics and Comparative Methods, and Experimental Design.

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Friday, Mar 30
A-247 LSRC
1:15-2:30 pm

Is carbon cycle science ready for the financial big leagues?
Steve Running
Professor/Director, Numerical Terradynamic Simulation Group, College of Forestry & Conservation, University of Montana

Co-sponsored with the Duke University Program in Ecology

Study of the terrestrial carbon cycle has progressed substantially in the last 30 years, with field gas exchange measurements, FACE facilities, integrated biogeochemical modeling of carbon-water-nitrogen cycles, atmospheric inversion modeling, and satellite-driven global biophysical datasets. Meanwhile, societal interest in carbon sequestration and biofuels - issues bounded by ecosystem carbon cycles - is accelerating dramatically. Ecologists now have much more theory, data, models, and integration than 30 years ago, but the amount of money poised to be spent on "carbon cycle components" as financial commodities is immense and daunting. Is our science advanced enough, are our measurements precise enough, and are our projections accurate enough to make trillion dollar social decisions? (Conversely, are our methods and results any worse than the economic models and measurements that currently run our country?) This talk will describe the development of terrestrical carbon-cycle ecology, discuss its current measurement and modeling uncertainties, and speculate on its future applications in the global carbon market.

Steven W. Running is trained as a terrestrial ecologist, receiving the B.S. (1972) and M.S. (1973) degrees from Oregon State University, and the Ph.D. (1979) degree in Forest Ecology from Colorado State University. He has been with the University of Montana, Missoula, since 1979, where he is a Professor of Ecology. His primary research interest is the development of global and regional ecosystem biogeochemical models by integration of remote sensing with climatology and terrestrial ecology. He is a Team Member for the NASA Earth Observing System, Moderate Resolution Imaging Spectroradiometer and is responsible for the EOS global terrestrial net primary production and evaporative index datasets. He has published over 240 scientific articles. He currently serves on the standing Committee for Earth Studies of the National Research Council, and on the federal Interagency Carbon Cycle Science Committee. He is a Co-Chair of the National Center for Atmospheric Research Community Climate System Model Land Working Group, a Member of the International Geosphere-Biosphere Program Executive Committee, and the World Climate Research Program, Global Terrestrial Observing System. Dr. Running is a chapter Lead Author for the 4th Assessment of the Intergovernmental Panel on Climate Change. Prof. Running is an elected Fellow of the American Geophysical Union and is designated a Highly Cited Researcher by the Institute for Scientific Information.

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Thursday, Apr 5
A-158 LSRC
4:00-5:15 pm

The late quaternary paleoenvironments of the South American tropics
Edgardo M. Latrubesse
Professor of Geomorphology at the Institute of Soils and Geomorphology of the Universidad Nacional de La Plata, Argentina, and Researcher for CONICET (National Council of Research of Argentina).

Co-sponsored with the Nicholas School Earth & Ocean Sciences Division, & Center for Latin American and Caribbean Studies, Duke University

In this seminar we present results on the impact of global changes on the tropical areas of South American during the Late Pleistocene and Holocene. Recent research on fluvial and aeolian deposits, vertebrate paleontology, palynology, together with geomorphologic studies demonstrates that the tropics of South America suffered drastic climatic, palaeogeographic and plaeoecologic changes during the Late Pleistocene.

The best record of fluvial deposits in the large basins is related to the Middle Pleniglacial (~55-28 ka) when more torrential deposits were in general deposited along all the sub-continent. Climate was characterized by highly seasonal rainfall indicating that a climatic deterioration begun before to the Upper Pleniglacial. Also, widespread eolian dune fields generated in the South American tropical areas such as the Amazon basin, the Orinoco Llanos and probably in the Chaco area of Bolivia. Giant longitudinal dunes up to 100 km length were also recorded in the southern part of the continent, specifically in the Pampean plains of Argentina.

The Upper Pleniglacial (28-14ka) is characterized by the scarcity of fluvial data. Apparently low discharges and dissection were the fluvial response to the climatic changes during the Last Glacial Maximum. Aeolian activity continues to spread on the large South American plains.

A recuperation of fluvial activity is noted during the Lateglacial (14-10ka). Well developed terraces with fine sediments are frequent in tropical rivers and the recuperation of tropical rainforest happened at this time. The Holocene is marked by minor climatic variations and the late Pleistocene-Holocene limit is not clearly identified in the fluvial record. A main climatic change is produced by the Hypsitermal of the late early-middle Holocene but it s not clearly recorded along the lowlands of tropical South America.

Youngest climatic oscillations are produced to 3,5 and ~1 ky. In the lowlands of middle latitudes but not in the tropical lowlands the LIA was also detected.

Professor E. Latrubesse is one of the most prominent and widely published geomorphologists in South America. At present he is Professor of Geomorphology at the Institute of Soils and Geomorphology of the Universidad Nacional de La Plata and Researcher of the CONICET (National Council of Research of Argentina). Over the past 16 years, he has conducted fieldwork on the Quaternary geomorphology of the Amazon, the Pampean region, the Bolivian Altiplano, the Cerrado region (Brazilian savannas), and the Chaco and Llanos del Orinoco (Venezuela). Dr. Latrubesse has chaired several national and international projects. He has conducted research on some of the largest rivers in South America, including the Amazon, the Negro, Madeira, Purus, Juruá, Araguaia-Tocantins, Paraná, Paraguay and São Francisco.

In applied research, Dr. Latrubesse has maintained multidisciplinary activities with specialists in ecology, geography and engineering, focusing on direct applications in the management of fluvial systems by undertaking consultancies on the Madeira, Sao Francisco (Brazil), Araguaia and Apure Rivers (Venezuela) and acted as consultant of UNPD-ONU, OAS, Geological Survey of Brazil and others for the largest Ecologic and Socio-Economic zoning projects of Brazil as expert in Geomorphology.

Dr. Latrubesse was elected member on the International Association of Geomorphologists (IAG) executive committee (2001-2005) and was member and co-founder of the Brazilian Union of Geomorphologists (UGB). He has been chair of the Working Group on Large Rivers (Global Commission on Continental Paleohydrology - GLOCOPH) since 1995. He has been a member of the Working Group on Large Rivers of the IAG since 1997, and is currently co-leader with D. Bridgland (UK) and R. Sinha (India) of the UNESCO Project IGCP 518 (Fluvial Sequences as Evidence for Landscape and Climatic Evolution in the Late Cenozoic, 2005 - onwards). Dr. Latrubesse currently sits on the editorial boards of Geomorphology, Paleoecology of Africa, Revista Brasileira de Geomorfologia and Acta Scientiarium. For his research on the human impacts on the large South American fluvial systems, Edgardo Latrubesse was the winner in 2005 of the International Prize Augusto Gonzalez de Linares offered in Spain to recognize centers or individuals of Spain and Latin America devoted to environmental studies.

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Wednesday, Apr 11
John Hope Franklin Center, Rm. 240
12:00-1:00 pm

Global Warming: Some Science and Solutions
Rob Jackon
Director, Duke Center on Global Change, and Professor, Department of Biology and Nicholas School of the Environment and Earth Sciences, Duke University

A luncheon seminar in conjunction with Wednesdays at the Center seminar series

Video of Rob Jackson's talk (327 Mb, QuickTime format)

For this talk, we will examine some of the scientific evidence for global warming.  We will then discuss some of the environmental consequences and possible solutions, including various ongoing efforts at Duke that contribute to those efforts.

Rob Jackson is Professor of Biology and Director of the Center on Global Change at Duke University.  His special research involves Biogeoscience, with focus on global carbon cycles and climate change research.  He currently leads the Department of Energy's Southeastern Regional Center of the National Institute for Climate Change Research, housed in the Center on Global Change.  As Director of the Center on Global Change, Jackson also is a collaborating principle investigator in the Climate Change Policy Partnership, a multi-year partnership with the Nicholas School of the Environment and Earth Sciences, the Nicholas Institute for Environmental Policy Solutions, and energy industry directors to address problems of global climate change.

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Thursday, Apr 19
Love Auditorium, Rm. B101 LSRC
4:00 pm
followed by a reception in the Hall of Science

Agricultural intensification in the Yaqui Valley, Mexico: will it spare land for nature?
Pam Matson
Dean of the School of Earth Sciences and Professor of Environmental Studies, Stanford University

The 2007 Henry J. Oosting Memorial Lecture, sponsored in conjustion with the Department of Biology.

Our group studies biogeochemical and ecological processes in forest and agricultural systems. In particular, much of our research focuses on the effects of land use change and other human caused changes on biogeochemical processes and trace gas exchanges in tropical ecosystems. Our research in the Yaqui Valley has dove-tailed with writing and policy work on issues of sustainability. As a member of the National Research Council’s Board on Sustainable Development, I used the Yaqui Valley as one of several case studies that argue for the need for “place-based integrative analysis” – understanding the dynamics and forces of change in the integrated social biophysical systems.

Pamela Matson is the Richard and Rhoda Goldman Professor of Environmental Studies in the Department of Geological and Environmental Sciences. She received a B.S. in biology from the University of Wisconsin in 1975, a M.S. in environmental science from Indiana University in 1980, and a Ph.D. in forest ecology from Oregon State University in 1983. Until 1993, she was a research scientist at NASA/Ames Research Center. From 1993-1997, she was a professor of ecosystem ecology at the University of California, Berkeley. She was elected to the American Academy of Arts and Sciences in 1992 and to the National Academy of Sciences in 1994. In 1995, Dr. Matson was selected as a MacArthur Fellow, and in 1997 was elected a Fellow of the American Association for the Advancement of Science. She currently serves as Past-President of the Ecological Society of America. In 2002 she was named the Burton and Deedee McMurtry University Fellow in Undergraduate Education at Stanford. Pamela Matson was appointed Chester Naramore Dean of the School of Earth Sciences in December 2002.

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Friday, Apr 27
A-247 LSRC
1:15-2:30 pm

The influence of tree species on biogeochemistry: Interactions among litter chemistry, earthworms and microbes
Sarah Hobbie
Associate Professor, Dept. of Ecology, Evolution and Behavior, University of Minnesota

Co-sponsored with the Duke University Program in Ecology

Although it is well-established that plant species can have differing effects on carbon and nitrogen cycling through litter because of interspecific variation in litter chemistry, the influence of plant species on soil carbon and nitrogen pools and their dynamics is less clear. Nevertheless, understanding how species influence soil organic matter dynamics is important to predicting how soil carbon sequestration and fertility will respond to management decisions and as well as global environmental changes that alter plant species composition across the landscape. In collaboration with Polish and US scientists, Dr. Hobbie studied the effects of tree species on leaf litter and soil organic matter decomposition in a common garden experiment of fourteen tree species in southwestern Poland. Tree species influenced microbial decomposition via differences in litter lignin, with high-lignin species decomposing more slowly. However, forest floor decay rates estimated from mass balance were positively related to leaf litter Ca (and unrelated to decay rates obtained using litter bags). Litter Ca was positively related, in turn, to the abundance of earthworms, particularly Lumbricus terrestris. Thus, apparently because of earthworm activity, differences among species in litter Ca, rather than litter lignin or N, are most important in determining species effects on leaf litter dynamics among these fourteen tree species. Soil organic matter decomposition and microbial biomass were also related to soil cation status: they were significantly negatively related to concentrations of exchangeable Al+Fe, likely because these cations stabilize SOM via cation bridging and flocculation and because of potentially toxic effects of Al on decomposers. Together, our results indicate that these tree species significantly influence litter and SOM dynamics, primarily through their effects on soil cation biogeochemistry. These species effects could be important in other poorly buffered systems dominated by tree species that differ in cation nutrition, and our results provide insights into systems experiencing invasion by Lumbricus terrestris or acidic deposition.

Dr. Hobbie graduated from Carleton College with a BA in biology in 1986, earned her PhD with Terry Chapin at UC-Berkeley in 1995, and received an NSF post-doctoral fellowship to work with Peter Vitousek at Stanford University. She is currently an Associate Professor and Director of Graduate Admissions in the Department of Ecology, Evolution and Behavior at the University of Minnesota. My current research is focused on understanding i) the nature of nutrient limitation of decomposition, ii) interactions among elevated CO2, nitrogen inputs, biodiversity and precipitation in model grassland communities, iii) the causes and ecosystem-level consequences of variation in calcium nutrition among temperate tree species, and iii) the patterns of biogeochemical fluxes through urban households. Dr. Hobbie is involved in research at both the Cedar Creek and Arctic LTER sites, and currently has funding for her research through NSF's CAREER, Biocomplexity, LTER, and Ecosystems Studies programs.

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Thursday, May 3
A-158 LSRC
4:00-5:15 pm

Global Warming and Water Availability
Christopher Milly
Research hydrologist, U. S. Geological Survey

Some of the basic physical processes that relate global warming to changes in water availability are accessible to the layperson: warm air can hold more water vapor than cool air, and ice melts when heated above a critical temperature. The higher water content of a warmer atmosphere implies changes in atmospheric transport of water to and from a given region, with direct consequences for surface runoff and groundwater recharge. The decreasing prevalence of ice and snow in a warmer world has fundamental implications for seasonal storage of water, for response of soil to precipitation, and for sea level.

The foregoing considerations lead to the admittedly vague prediction that a warmer world is a world in which water availability differs from that of a cooler world. Approximate quantitative expressions of this prediction have been produced by a series of increasingly complex global climate models over a period of many years. However, the water-availability predictions differ from one model to the next, and they depend on uncertain projections of human activities. Furthermore, global climate models address mainly physical processes and tend to ignore various biological and chemical feedbacks of potential importance (e.g., changes in plant structure and functioning, changes in soil carbon balance). Accordingly, skepticism toward projections of changing water availability is not inappropriate.

The projections of the most recent generation of climate models differ even in the direction of change of mean annual runoff (i.e., tendency toward wetter vs. drier conditions) in many regions. Nevertheless, the global pattern of projected change is broadly consistent across most models. Furthermore, the global pattern of multi-decadal trends in streamflow that was observed during the 20th Century bears a striking similarity to the average pattern simulated by the climate models forced by estimated historical drivers of climate (both anthropogenic and natural). This similarity appears too great to be explained readily by chance, but seems rather to indicate that the models have predictive skill for estimating future water-availability trends. The more robust projections of these same models driven only by possible anthropogenic forcings for the 21st Century imply decreasing water availability in southwestern North America, the Mediterranean region, and southern Africa, and increasing water availability in high-latitude North America and Eurasia, the La Plata basin of South America, eastern equatorial Africa, and Indonesia. In general, regions of projected decreasing water supply tend to be regions of contemporary water-supply stress, and regions of projected increasing supply tend to be regions where water shortage is not a major issue for water managers.

Dr. Milly is a research hydrologist with the U. S. Geological Survey and is stationed at NOAA's Geophysical Fluid Dynamics Laboratory in Princeton, NJ. He studies the relation between climate and continental water. His publications have addressed dynamics of water and energy in the subsurface boundary layer of the earth; controls on continental water balance; numerical modeling of global land water and energy balances; hydrologic forcing of geophysical processes such as sea-level rise, gravity transients, and earth deformation; and global hydroclimatic change.

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FALL 2006

Thursday, Sept 14
Old Chemistry Rm 116
4:20 pm

Note: new time and location!

Ocean Wave and Tidal Energy Conversion
Roger Bedard
Ocean Energy Leader, Electric Power Research Institute (EPRI), Palo Alto, California

Wave and tidal energy conversion are technologies whose time has come. Following extensive technology development over the past decade, primarily in Europe, North American electricity stakeholders are now becoming interested in applications of this technology. EPRI has conducted techno economic feasibility studies of wave and tidal energy over the past few years. These studies have had a significant impact. In June 2006, the first U.S. commercial wave energy project was announced, and a permit application filed with the Federal Energy Regulatory Commission (FERC). Within two months of completing the North America Tidal In Stream Energy Conversion (TISEC) feasibility study in May 2006, private investors have filed approximately 30 permit applications with FERC for commercial plants. In Nova Scotia, a multimillion pilot tidal plant was announced by Nova Scotia Power for the Minas Passage in the Upper Bay of Fundy. This presentation will summarize the energy resource, the energy conversion technology status, and the performance, cost and economics of preliminary Wave and Tidal power plant designs in various locations in North America. Grid interconnection, environmental and regulatory issues will also be described as will current wave and tidal projects in process, both in North America and worldwide.

Mr. Roger Bedard currently is Ocean Energy Leader at the Electric Power Research Institute (EPRI) in Palo Alto, California. He has over 40 years of experience developing and leading technology research, development and demonstration projects. He led a collaborative wave energy conversion technology feasibility study in 2004 with state energy agencies and utilities in Maine, Massachusetts, Northern California, Oregon, Washington and Hawaii. Mr. Bedard also led a collaborative in stream tidal energy conversion technology feasibility study in 2005 for state energy agencies and utilities in New Brunswick, Nova Scotia, Maine, Massachusetts, Alaska, Washington and California.

Prior to joining EPRI, Mr. Bedard was Vice President at Alstom Robotics where he managed custom robotic projects for nuclear waste cleanup; at NASA Jet Propulsion Laboratory he managed the Mars Rover, the Army unmanned land vehicle technology programs and point focus distributed receiver solar thermal electric technology programs; and at Acurex he managed rocket nozzle materials characterization, torsion meter and point focus distributed receiver solar thermal electric technology programs. As an active duty Air Force Officer at the AF Rocket Propulsion Laboratory, he managed solid rocket propulsion technology programs.

Mr. Bedard has a BS in Mechanical Engineering from the University of Rhode Island, a MS in Mechanical Engineering from the University of Southern California, an Electrical Engineering degree from the National Technical Institute of Electronics and is a graduate of the NASA Senior Management Education Program and a distinguished graduate of the Air Force Officers Training School.

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Thursday, Sept 28
A-158 LSRC
4:00 - 5:15pm

Spatial and temporal controls of carbon cycling in arid and semiarid ecosystems
Osvaldo E. Sala
Sloan Lindemann Professor of Biology and Director, Environmental Change Initiative; Director, Center for Environmental Studies, Brown University

The overall objective of this talk is to discuss patterns and controls of carbon cycling in arid and semiarid ecosystems through time and space and at different spatial scales from the region to the patch-scale. First the talk will describe large-scale patterns of primary production for the region of the Central Plains of the US and identify its major controls. The spatial controls will be contrasted with the controls of primary production through time. The talk will postulate hypotheses for the differences between spatial and temporal controls and will describe manipulative field experiments that addressed the hypotheses. The concept of lags in the ecosystem response to increases in water availability would be central to understanding the differences between spatial and temporal models. At a more detailed scale, the talk will describe spatial patterns of production and decomposition for a site in the Patagonian steppe. The relationship between vegetation spatial patterns and the rates of production and decomposition suggest the relative importance of the controls of production and decomposition. The talk concludes, with suggestions about the changes in the relative importance of controls of ecosystem processes with scale, from the region to the patch.

Dr. Osvaldo Sala is the Sloan Lindemann Professor of Biology at Brown University, where he serves as director of the Environmental Chance Initiative and of the Center for Environmental Studies. He is also the Andrew D. White Professor-at Large from Cornell University. Dr. Sala's expertise in ecology extends from the arid ecosystems of Patagonia to global change issues, including carbon cycle questions, ecosystem-water dynamics, biodiversity and ecosystem functioning, and biodiversity scenarios. His current research projects involve ecosystems and places as diverse as the Chihuahuan Desert in New Mexico and the Harvard Forest in Western Massachusetts. With more than 140 peer-reviewed publications, Dr. Sala is president of the Scientific Committee on Problems of the Environment, and a current member of the Science Council, The Nature Conservancy. Dr. Sala is an elected member of the American Academy of Arts and Sciences, the Argentinean National Academy of Sciences, and the Argentinean National Academy of Physical and Natural Sciences.

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Friday, Oct 27
A-247 LSRC
1:15 - 2:30pm

Co-Sponsored with the Duke University Program in Ecology

The manner and magnitude by which trees impact the hydrological cycle
Todd E. Dawson
Center for Stable Isotope Biogeochemistry & the Departments of Integrative Biology and Environmental Science, Policy and Management, University of California - Berkeley

There is now ample evidence that plants can exert a very significant and often dominant "control" over the nature by which water cycles through diverse ecosystems on Earth (Lee et al. 2005, Gedney et al. 2006). The diverse manner by which water loss from plant canopies occurs as well as the nature of water uptake and redistribution of soil water by deep root systems happens are two primary ways plants impact the hydrological cycle (Dawson and Ehleringer 1998, Jackson et al. 2000, Feddes et al. 2001). When these functional behaviors are measured in relation to land-use and/or climatic changes that in turn modify the vegetation there are fundamental changes in how water cycles that are linked to plants (Dawson et al. in review). For more than a decade my research group has developed and used a range of methods to study above- and below-ground water flux in a diversity tree species inhabiting temperate and tropical biomes with the objective of enhancing our understanding of their role in hydrological processes. In addition, collaborative research has incorporated tree water use behavior into atmospheric general circulation models to estimate plant impacts on the magnitude and manner by which water moves through the landscape and on the climate itself over areas such as the Amazon basin and temperate evergreen and deciduous forests. This empirical and modeling research shows that plants can help sustain water recycling that in turn has important impacts on other biogeochemical cycles, on climate, and on the seasonality of water (and carbon) fluxes thereby establishing a direct link between plant functioning, water movement on the globe and the climate system.

Todd E. Dawson is a professor in the Departments of Integrative Biology and Environmental Science, Policy and Management at UC Berkeley. He received his PhD in Plant Biology and Ecology from the University of Washington. For the last 15 years his research has focused on the ecology and physiology of woody plants in diverse environmental contexts. Dawson's research has addressed topics such as the evolution of functional adaptations in response to drought in trees, the ecophysiology of plant water use in trees and shrubs, and biological and physical controls over plant response to naturally and anthropogenically imposed environments. He directs the Center for Stable Isotope Biogeochemistry at UC Berkeley that provides education, training and research opportunities for Berkeley students and visitors who want to incorporate isotope approaches and analyses into their research. Dawson is also the director of the Biogeosphere-Atmosphere Stable Isotope Network (BASIN), an NSF-sponsored program, now in its second phase, this is focused on the use of stable isotopes in land-use and global change research with particular emphasis on the hydrological cycle. He is also a member of several societies committed to advancing the fields of ecology, environmental science and sustainable solutions to forest and agricultural practices.

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Friday, Nov 3
A-247 LSRC
1:15 - 2:30pm

Co-Sponsored with the Duke University Program in Ecology

Sunshine, waterbugs and real estate: unique controls on litter decomposition in arid ecosystems
Amy Austin
Research Scientist, University of Buenos Aires and IFEVA, Argentina

Controls on decomposition and nutrient turnover in arid ecosystems are elusive, as many studies of litter decomposition have shown contradictory results and little correlation with annual precipitation or pulsed rainfall events. At the same time, the difference between inputs and losses of carbon will ultimately determine the carbon balance of these ecosystems that currently occupy nearly 40% of the terrestrial land surface. Predictions of litter decomposition based on rainfall often underestimate mass loss in deserts; standard litter quality indices such as lignin or nitrogen rarely correlate with decomposition. These conflicting results inspired a series of descriptive and manipulative experiments in natural ecosystems of Patagonia, Argentina, where we attempted to evaluate if there are unique controls affecting litter decomposition in "water-limited" ecosystems. Typical of arid and semiarid ecosystems is the patchy distribution of vegetation, which results in large amounts of standing dead material and exposed bare soil areas. The well-documented “islands of fertility” from shrub patches also contribute to variability in soil resource availability and microclimatic conditions, all factors that could be important in affecting litter decomposition. We found that direct effects of solar radiation and location are fundamental controls on mass loss of aboveground litter, and the predominance of abiotic over biotic factors affecting carbon turnover suggest that traditional models of carbon cycling developed for temperate mesic forests may not apply to these ecosystems. In addition, global change effects such as changes in cloudiness or vegetative cover may be more important in impacting carbon turnover in these ecosystems than elevated temperature or altered precipitation regimes.

Amy Austin is a research scientist and lecturer at the University of Buenos Aires and the CONICET research institute of IFEVA, Argentina. Her research interests are focused in the area of terrestrial ecosystem ecology, particularly related to abiotic and biotic controls on ecosystem processes. She completed her undergraduate degree in environmental sciences at Willamette University and her doctoral degree with Peter Vitousek at Stanford University, working in Hawaiian forest ecosystems. Starting with a NSF postdoctoral fellowship to work in Patagonia, over the last several years she has been exploring a number of questions related to the effects of water availability on carbon and nutrient turnover in undisturbed natural ecosystems of southern temperate Argentina, ranging from xeric shrublands to southern beech forests. One area of active research is how 'water-limited' are arid and semiarid ecosystems - are there factors other than water availability which are important in controlling carbon and nitrogen turnover? In addition, she is very interested in how vegetation generates spatial heterogeneity of carbon and nutrient resources in both grassland and forest sites and the consequences for belowground processes. She also continues to explore the use of stable isotopes, particularly the natural abundance of 15N, as a way to elucidate the integrated ecosystem response to changes in water, temperature and land use change. For a list of publications and more information on her research: http://www.agro.uba.ar/users/austin/

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Tuesday, Nov 28
A-158 LSRC
4:00 - 5:15pm

Using micrometeorological techniques to determine the impact of land use change on "Green water": Examples from South Africa
Caren Jarmain
Ecophysiology research group, Council for Scientific and Industrial Research (CSIR), Pretoria, South Africa

Accurate total evaporation estimates are required when assessing the impact of different land uses on the water balance and the availability of water in streams. The provisions of the National Water Act of South Africa (1998) require water resource managers to assess whether different land-uses within a catchment or exchanges thereof, are likely to reduce the quantity and temporal availability of water to downstream users. Such decisions need to be based on the relative annual and seasonal water use (total evaporation) of existing and proposed crops or vegetation and how these affect river flows. Although commercial forest plantations are currently the only legislated Stream Flow Reduction Activity (SFRAs) within South Africa, a wide range of agricultural crops and baseline vegetation may have to be considered as SFRAs.

The recently defined "Green Water" concept recommends that SFRA assessments be simplified by focusing on monitoring the evaporation from different land uses, rather than the flow in rivers as such. This has particular relevance to the emerging concept of "exchange ratios" in which water use is considered in terms of changing land use from one crop to another (e.g. from forestry to sugarcane). The difference in water use between the land use types then becomes particularly critical, especially with regards to SFRA licensing issues. Apart from SFRAs other key water resource management applications in South Africa also require accurate estimates of total evaporation, e.g. where ground water recharge is considered, as part of irrigation scheduling, mine water management (specifically pollution containment and acid mine drainage), industrial land rehabilitation and ecosystem management.

An overview is given of (1) studies pioneering micrometeorological and other techniques to ensure accurate estimates of total evaporation which meet the precision requirements set by water resources managers, and (2) applications of micrometeorological and other related techniques to different water resources applications to determine the impact of land use change on total evaporation ("green water").

Caren Jarmain is currently part of the Ecophysiology research group within the CSIR. Their research involves 1) Estimating the impact of land use of hydrology, focussing specifically on the total evaporation ("green water") component, 2) Pioneering techniques for estimating total evaporation, 3) Application of Remote sensing data for water resources management in South Africa, and 4) Application of micrometeorological techniques to compliment air pollution modeling. Other research interests include: Plant-soil-water relationships of natural veld types of South Africa (indigenous vegetation) vs. invading species, agricultural crops, commercial forestry species, etc.; Advances in Micrometeorological and other methods (including methods based on remote sensing data) used to estimate total evaporation; and Biogenic volatile organic carbon estimates as an input to regional air pollution modeling. Dr. Jarmain received a B.Sc. Agric Hons. (1998) in Agrometerology from the University of the Orange Free State, South Africa, and a M.Sc (1999) and Ph.D.(2003) in Agrometerology from the University of Natal, South Africa.

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Friday, Dec 1
A-247 LSRC
1:15 - 2:30pm

Co-Sponsored with the Duke University Program in Ecology

The challenge of representing nitrogen cycling in global biogeochemical models
Lars Hedin
Professor of Terrestrial Biogeochemistry, Department of Ecology and Evolutionary Biology, Princeton University

Nutrient feedbacks in land ecosystems represent one of the greatest sources of uncertainty in global carbon cycle over the next half century.  In this seminar, I will address some of the difficulties of incorporating a dynamic nitrogen cycle in terrestrial biogeochemical models.  By using empirical studies and theoretical considerations, I will discuss the need to capture a set of key processes that act over time to determine how nitrogen cycles develop across broad geographical regions.  I will specifically consider the role of hydrology, plant nutritional strategies, and climate in shaping the terrestrial nitrogen cycle.

Dr. Lars Hedin is a professor in Terrestrial Biogeochemistry at Princeton University.  For over 15 years his research has focused on how diverse forested ecosystems depend on nutrients and nutrient cycles.  His contributions include studies of atmospheric dust and acid rain in forests, thermodynamics and nitrogen cycling in riparian wetlands, the development of nutrient cycles over geological time, and the role of nutrients in plant competition and community assembly.  His current work includes analysis of plant strategies in the context of complex adaptive systems that change functionally across climate and biomes.  Dr. Hedin is the recipient of the Mercer Award from the Ecological Society of America for his work on using pristine South American forests as a “baseline” for understanding pre-industrial nutrient cycles.  He is the founder of the biogeosciences section of the Ecological Society of America and recently chaired a white paper report on “Challenges to Linking Ecological Biology and Geosciences.”

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SPRING 2006

Tuesday Jan 17
A158 LSRC
4:00 - 5:15

Taking your story to the next level
Julie Wakefield
CGC Science Writer in Residence, 16-21 January, 2006

Whether you're interested in writing your first book or having a journalist tell your story or would just like to reach a broader audience, learning more about the seemingly arbitrary and even nefarious world of science writing and publishing can help to build your communications platform.

Author and journalist Julie Wakefield will share her insights on everything from developing relationships with the media to getting an agent and a book contract to the importance of educating the public about your research. Getting your name and work out there may also help in securing a bigger seat for scientists like yourself at the policymaking table. Her talk will address some of the natural tensions that arise with academia when endeavors are undertaken to popularize science for a general audience. She also will discuss some of the latest trends in science writing, such as the creative nonfiction rage and the proliferation of blogs.

The Joseph Henry Press, a trade imprint of the National Academies Press, published Wakefield's first book Halley's Quest: A Selfless Genius and His Troubled Paramore, in fall 2005. The nonfiction narrative reveals the life of Edmond Halley of comet fame through his sea adventures undertaken more than 300 years ago aboard Her Majesty's Ship, the Pink Paramore. The work establishes Halley as the father of geophysics and more.

Wakefield's writing has been published in such general interest publications as Smithsonian, The Washintonian, and Washington City Paper. She has also written for Scientific American, New Scientist, and Wired, among others.

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Thursday Jan 19
A158 LSRC
4:00 - 5:15

Ecosystem consequences of insect defoliation in the Appalachians
Philip A. Townsend
Department of Forest Ecology and Management, University of Wisconsin-Madison

While the effects of major forest disturbances such as logging, fire or hurricanes can be readily observed and measured, most natural forest disturbances are in fact: (1) ubiquitous, (2) transient, (3) highly variable in extent, frequency, and intensity, and (4) often "stealthy" and poorly documented in both spatial and temporal dimensions. The impacts on ecosystem processes of such disturbances such as periodic insect defoliation are likewise poorly characterized. We have used remote sensing and field measurements to characterize the impacts of gypsy moth defoliation on forest and watershed nutrient dynamics in the Central Appalachians. We demonstrate that remote sensing based measures of forest disturbance can be used to accurately predict nitrogen export from watersheds (R² > 0.7). Remotely> sensed estimations of foliar biomass loss are reliable within 500 kg/ha/yr total biomass. The analyses show nitrogen loss due to defoliation can surpass 30 kg/ha/yr.

Phil Townsend is an Associate Professor in the Department of Forest Ecology and Management at the University of Wisconsin-Madison. He was previously on the faculty at the University of Maryland Center for Environmental Science, Appalachian Laboratory, and received his Ph.D. in 1997 from the University of North Carolina. His research interests center on watershed hydrology and forest dynamics, and in particular with the application of remote sensing and the modeling of environmental processes to assess fluxes of water, sediments and nutrients from forested and mixed-use watersheds, as well as wetlands. His work emphasizes linkages between ecosystem function (nitrogen and carbon cycling), plant community dynamics, watershed hydrology and landscape ecology. Major tools of the work include remote sensing and GIS as integrated with field measurements. Dr. Townsend's major research projects involve studies of ecosystem dynamics (N and C cycling) and ecohydrological impacts associated with insect defoliation in the Central Appalachian Mountains and Upper Midwest, testing and validation of new remote sensing technologies for application to ecosystem and community studies, examination of relationships between sedimentation and changes in flooding on ecological processes on floodplains, and predictive modeling of species distributions and patterns. This research has been funded by NASA, NSF, The Nature Conservancy, EPA, USGS, USDA and the US Forest Service.

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Thursday February 9
A158 LSRC
4:00 - 5:15

The Role of Dry-Season Orographic Precipitation in the Cloud Forests of Monteverde, Costa Rica
Andrew Guswa
Picker Engineering Program, Smith College

Monteverde, Costa Rica harbors montane forests that exemplify the delicate balances among climate, hydrology, habitat, and development. Most of the annual precipitation to this region arrives during the wet season, but the importance of orographic precipitation during the dry and transitional seasons should not be underestimated. A boom in ecotourism has put significant stress on water resources, and recent work has shown evidence that changes in regional land-cover and global climate may lead to reduced precipitation and cloud cover and a subsequent decline in endemic species. The potential for reduced supply, the reality of increased demand, and the effect on ecosystem function requires a better understanding of the role of orographic precipitation during the dry and transitional seasons.

During the dry and transitional seasons (November through April), the trade winds bring moist air up the Atlantic slope, and the interception of fog, mist, and wind-blown rain by forest vegetation can provide a significant hydrologic input. Previous investigations in Monteverde have had some success in quantifying the contribution of cloud-water interception to the hydrologic budget. Our work complements and builds upon these efforts by focusing on understanding the contribution of precipitation as a function of season and condensation mechanism rather than as a function of deposition mechanism. We seek to understand how precipitation from the drier seasons propagates through the hydrologic cycle.

From 2003-2005, we collected precipitation and streamflow samples to determine the abundance of oxygen-18 and deuterium, quantified as the deviation from Vienna Standard Mean Ocean Water. These stable isotopes of oxygen and hydrogen can serve as conservative tracers of liquid water, and their relative proportion (as characterized by deuterium excess) can be used to determine the contribution of evaporation from land to precipitation and surface waters.

On the leeward slope of Monteverde, we observe seasonal signals in d¹⁸O, dD, and d-excess of precipitation. d¹⁸O and dD are heaviest during the dry and transitional seasons and light during the rainy season, consistent with the condensation mechanisms and degree of rainout typical of these periods. The signal in d-excess indicates a contribution of recycled water to precipitation in Monteverde from late in the rainy season through the dry season. Attenuated versions of these seasonal signals propagate through to the stream samples and provide a means of determining the importance of dry-season precipitation to water resources for the region. Results from six catchments on the leeward slope indicate that local topography exerts strong control on the input of orographic precipitation to the region. Watersheds in close proximity to the Brillante Gap in the continental divide show evidence of significant contributions of dry-season precipitation to streamflow. Baseflow in catchments downslope show negligible contributions of precipitation from the drier seasons. Discrepancies in the temporal variability of isotopic composition in precipitation and streamflow indicate complex hydrologic transport processes in the headwater catchments.

In 2001, Drew Guswa joined the faculty at Smith College to help launch the Picker Engineering Program - the first engineering program at an all-women's college. As a civil and environmental engineer, he views his research as an opportunity to make manifest his commitment to the environment through continually acquiring engineering and analytical skills and applying them to new challenges. The overarching goal of his work is to improve our understanding and representation of hydrologic processes to facilitate informed decision-making. He is particularly interested in the interactions between one's predictive goals and tolerance for uncertainty, and one's characterization of the spatial and temporal variability of model parameters and representation of the physical processes. Recent areas of research include the ecohydrology of water-limited ecosystems and an investigation of the role of dry-season precipitation in the tropical montane cloud forests of Monteverde, Costa Rica. Guswa is a member of the American Society of Civil Engineers and the American Geophysical Union. He and his wife, Sue (Duke class of 1994), are enthusiastic fans of Duke basketball.

Selected Publications

• Guswa, Andrew J., 2005. Soil-moisture limits on plant uptake: An upscaled relationship for water-limited ecosystems, Advances in Water Resources, 28 (6), 543-552.
• Rhodes, A. L., A. J. Guswa, and S. E. Newell, in press. Using stable isotopes to identify orographic precipitation events in Monteverde, Costa Rica. In: Bruijnzeel, L.A., Juvik, J., Scatena, F. N., Hamilton, L. S., and Bubb, P. (eds.), Forests in the Mist: Science for Conservation and Management of Tropical Montane Cloud Forests, University of Hawaii Press.
• Guswa, Andrew J., M. A. Celia, and I. Rodriguez-Iturbe, 2002. Models of soilmoisture dynamics in ecohydrology: A comparative study, Water Resources Research, 38 (9).
• Guswa, Andrew J., and D. L. Freyberg, 2002. On using the equivalent conductivity to describe solute spreading in geologic environments with lowpermeability lenses, Water Resources Research, 38 (8).

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Thursday February 23
A158 LSRC
4:00 - 5:15

McMurdo dry valleys long-term ecological research: The response of Antarctic terrestrial ecosystems to climate change
W. Berry Lyons
Director of the Byrd Polar Research Center, Ohio State University

The McMurdo Dry Valleys (MCM) at ~78 degrees S Lat are the largest expanse of ice-free area on the Continent. The landscape is a mosaic of glaciers, bedrock, soils, ephemeral streams and ice-covered lakes. These valleys have been the location of an NSF supported Long-Term Ecological Research (LTER) site since 1993, and are termed polar desert ecosystems. The primary focus region of the MCM-LTER is Taylor Valley which has a mean annual temperature of ~ -20 degrees C. The role of climate variation has been important in influencing overall ecosystem development and function. Small variations in temperature, albedo, etc. have great ecological consequences. Small changes in climatic parameters are amplified through the change of state of H₂O. The production, transport and accumulation of liquid water is the key to the overall understanding of how the ecosystem works. I will review the 12 years of data from MCM-LTER and describe the linkages between climate change, the hydrologic cycle and ecosystem dynamics in this environment. This coupling between meteorology, hydrology and biology is very tight and is critical to our prediction of how these ecosystems will respond to future change.

W. Berry Lyons earned a bachelors degree in geology from Brown University and has MS and PhD degrees in chemical oceanography from the University of Connecticut. He has held faculty positions at the University of New Hampshire, University of Nevada, Reno, the University of Alabama (where he held the Loper Chair in Environmental Geology) and is currently a Professor in the Geological Sciences Department at the Ohio State University. He is also the Director of the Byrd Polar Research Center at OSU and is the lead PI of the McMurdo Dry Valleys Long-Term Ecological Research (LTER) project. His current research interests include the relationship between chemical and physical weathering, the role of agricultural activities and urbanization on water quality, the global mercury (Hg) cycle and polar biogeochemistry.

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Thursday March 2
A158 LSRC
4:00 - 5:15

Disturbance and Invasive Species in Tropical Rain Forests: New Ecological Insights from Remote Sensing
Gregory P. Asner
Department of Global Ecology, Carnegie Institution, Stanford University

The world of airborne and satellite remote sensing is changing fast, and today's capabilities far exceed those of just a decade ago. Remote sensing can support assessments of ecosystem services by offering a means to scale field-based measurements from local to regional levels. Current technologies from Earth orbit are limited in capability, but advances in analysis methods are providing new regional information in the areas of forest structure and disturbance. Current airborne remote sensing approaches are far more capable than space-based technologies, and include detailed assessments of ecosystem carbon stocks, fire fuel loads, invasive species and biological diversity. This presentation will show how the sciences of remote sensing and biogeochemistry can come together to better understand a range of terrestrial ecosystem processes in the context of conservation, management and policy.

Greg Asner is a faculty member in the Department of Global Ecology at the Carnegie Institution located at Stanford University. His scientific interests center on how human activities alter the structure and function of terrestrial ecosystems. Dr. Asner combines field studies, airborne and satellite remote sensing, and computer simulation models to address ecological phenomena related to land use, carbon cycling and climate change. His remote sensing efforts center on the use of new technologies for studies of vegetation structure and chemistry in the context of conservation and management, biogeochemistry, and the carbon cycle. Greg focuses much of his attention on tropical forests and rangeland ecosystems.

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Thursday March 23
A158 LSRC
4:00 - 5:15

Earth System Modeling at the Intersection of Science and Policy
Hiram Levy II
Senior Research Scientist at the Geophysical Fluid Dynamics Laboratory/National Oceanic and Atmospheric Administration

After a short discussion of climate change issues and Earth System Modeling, I will focus on 2 topics:
1. Mineral dust, air pollution, soluble/bioavailable iron and ocean biogeochemistry;
2. Methane - two for the price of one and recent concentration trends.

Dr. Hiram (Chip) Levy received a Ph.D. in Chemistry from Harvard University in 1966. After post-doctoral work in theoretical chemistry at Massachusetts Institute of Technology and working as a Research Scientist in atomic and molecular physics at the Smithsonian Astrophysical Observatory, he joined the Geophysical Fluid Dynamics Laboratory (GFDL) in 1973. He has been a government scientist since 1975, a Senior Research Scientist since 1998, and is Leader of the Biospheric Processes Group studying the interactions and feedback of the earth's biosphere with its climate and assessing the impact of natural variability and past, present, and future human activities. Dr. Levy has been a visiting Professor at the University of Michigan and the University of Iowa. He has written or co-authored more than 70 papers on global change, atmospheric chemistry and atomic and molecular physics. He has served on numerous National Academy of Sciences panels, as an Editor of EOS and as an Associate Editor for the Journal of Geophysical Research. He is also a Lecturer in the Atmospheric and Oceanic Science Program at Princeton University, where he has taught Atmospheric Chemistry since 1987. He was named a Fellow of the American Geophysical Union in 1998.

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Friday April 21
A148 LSRC (conference room)
11:30am - 12:30pm

A Moral Climate? The Ethics of Global Warming
Michael Northcott is visiting Duke and will talk about his new book on the ethics of climate change:

A Moral Climate? The Ethics of Global Warming, London: Darton, Longman and Todd, 2006, by Michael Northcott.

From Noah to Newton human beings believed that their actions affected the climate. But Isaac Newton with his mechanistic account of physical laws trained moderns to believe the cosmos was no longer a moral place. With the advent of the new discipline of biogeochemistry, riding as it does on Lovelock's Gaia hypothesis, humans are again learning that there is a relationship between their behaviours and the climate. However they are learning this at the same time as embracing liberal economic and moral philosophies which train them to believe that there are no limits to self expression, and that personal preferences - rational and emotional - are the key drivers of moral action as well as economic behaviour. The threat of climate change therefore presents a challenge both to post-Newtonian cosmology and to the moral climate of modern liberalism. Narrating the science of climate change is not therefore sufficient as a public policy response. Equally important is the recognition of the biophysical limits of liberalism, and efforts to resituate descriptions of human morality in cosmological narratives, including those of the major religious traditions.

Michael Northcott is Reader in Christian Ethics in the University of Edinburgh and a priest in the Scottish Episcopal Church. He serves as Associate Rector at St James', Leith and he is also a Canon Theologian of Liverpool Cathedral. In the 1980s he was a USPG sponsored mission priest in West Malaysia where he was lecturer in the Seminari Theologi Malaysia in Kuala Lumpur, and before that he served in the Diocese of Manchester. He speaks and writes widely on ethics and current affairs. His book Life After Debt: Christianity and Global Justice (London: SPCK, 1999) explores the ethics of international debt and trade justice, and his book An Angel Directs the Storm: Apocalyptic Religion and American Empire (London: I. B. Tauris, 2004) examines the moral implications of the war on terror. He is currently working on the ethics of climate change. His forthcoming book in this area is entitled The Moral Climate: The Ethics of Global Warming (London: Darton, Longman and Todd, 2006).

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Friday May 19
A148 LSRC (conference room)
4:00 - 5:15 pm

Water vapour and carbon dioxide fluxes from pine forest
Dr. John B. Stewart
University of Southampton, Department of Geography

Description of the background to the setting up of the Thetford Forest Project - replacement of sheep grazing by forests in reservoir water-sheds and some evidence that runoff from forests less than from grasslands in UK. Controversersy between Howard Penman and Jack Rutter about factors controlling evaporation. Uncertainities resolved by micrometeorological study - description of measurements/data acquisition/modelling. Measurements and analysis of carbon dioxide fluxes. Relevance to climate change.

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FALL 2005

Thursday Sept 8
A158 LSRC
4:00 - 5:15

C and N cycling in grasslands of Argentina and Uruguay: livestock introduction and its consequences
Gervasio Piñeiro, Universidad de Buenos Aires, Argentina
project researchers:
Gervasio Piñeiro(1); J.M. Paruelo (1); M.O. Oesterheld (1); E.O. Jobbagy (2); R.B. Jackson (3)

1- IFEVA/FAUBA, Buenos Aires. 2- Conicet, San Luis. 3- Duke University.

Grazing by domestic herbivores at high stocking rates, can alter the structure and function of natural grasslands. We evaluated the effects of grazing on the “Rio de la Plata” grasslands of South America using CENTURY, a process based biogeochemical model and field experiments. Contrary to prior studies, our ecosystem level simulations of grazing impacts showed a reduction in SOC associated with a more open and leaky nitrogen cycle that constrains long-term organic matter formation. To evaluate these results, we selected 13 grazing-exclosure sites in the “Rio de la Plata” grasslands of Uruguay. We sampled soil and roots and measured carbon and nitrogen contents at six depths in two different soil size fractions: the particulate organic matter (POM) of rapid turnover and the mineral associated organic matter (MAOM) of low turnover. As CENTURY simulations, our field results showed that grazing reduces total SOC in deep soils, but field data showed opposite trends in shallow soils. Grazing severely altered the vertical distribution of C in POM, increasing this labile SOC fraction towards the surface while decreasing C and N contents in the MAOM fraction in depth. The higher root contents (and belowground C inputs) measured at the surface in the grazed areas could be explaining the raise of surface POM, while other mechanisms are discussed for the accumulation of N in deeper horizons under grazing exclosure.

Gervasio Piñeiro was born in Buenos Aires Argentina on April 1973. A few years later he moved to Montevideo in Uruguay, where he made his school studies all through to the University. He obtained an Agricultural Engineering title at the Universidad de la República, Uruguay in 1999 and in the same year initiated his MSc courses at the Universidad de Buenos Aires in Argentina. He is currently enrolled in a PhD program at this University funded by CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas) and is a teaching assistant in Ecology since 1999. His research is now focused in understanding livestock impacts on ecosystem structure and functioning, and developing sustainable managerial practices for grasslands of southern South America. (more info at www.ifeva.edu.ar/en/staff/pineiro.htm)

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Thursday Oct 27
A158 LSRC
4:00 - 5:15

What are the most important factors for climate—carbon cycle coupling?
S. C. Wofsy, Dept. of Earth and Planetary Science, and Division of Engineering and Applied Science, Harvard University.
Contributors include: J. W. Munger, S. P. Urbanski1, C. C Barford2, L. Hutyra, S. R. Saleska3, and A. L. Dunn
Current addresses: 1USFS,Missoula, MT; 2U. Wisconsin, Madison WI; 3U. Arizona, Tucson AZ.

The mechanisms that drive changes in ecosystem carbon balance in response to climate change are evaluated using data from long-term measurements of CO₂ fluxes, environmental parameters, and ecological factors in boreal, mid-latitude and tropical ecosystems. We find that most model parameterizations overestimate the temperature sensitivity of ecosystem respiration and underestimate the role of soil water balance in controlling respiration and flammability. We conclude that models of climate—carbon feedbacks must carefully simulate regional precipitation, evaporation, evapotranspiration, and water balance, including factors leading to fires (e.g. sources of ignition), in addition to assessing changes in temperature. Covariances among these drivers of ecosystem change, along with the severity and frequency of extreme events, may also be critically important for understanding coupling between ecosystems and climate.
click for extended abstract >

Professor Steve Wofsy is Abbott Lawrence Rotch Professor of Atmospheric and Environmental Science, and Associate Dean of the Faculty of Arts & Sciences (FAS). at Harvard University. Professor Wofsy and colleagues are studying CO₂ and other important atmospheric gases at long-term measurement stations located from the subarctic to the equator, complemented by atmospheric measurement campaigns using aircraft such as the University of North Dakota Citation II and NASA's ER-2 and WB-57F. Analysis and modelling studies aim to extract quantitiative information about sources, sinks, transformations, and transport of atmospheric trace gases, to help understand the factors that regulate atmospheric composition and to help design programs to mitigate undesirable change. Wofsy received a B.S. in Chemistry at the University of Chicago (1966), an M.A.(1967) and Ph.D. (1971) in Chemistry from Harvard University. For more information on Professor Wofsy , a list of his publications, and projects, see his website, http://www.deas.harvard.edu/ourfaculty/profile/Steven_Wofsy; and also click on “Personal Link”.

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Tuesday Nov 1
A158 LSRC
4:00 - 5:15

Interactive impacts of vegetation on hydrology and soil chemistry: The grassland afforestation experiment
Esteban Jobbágy, Grupo de Estudios Ambientales, Universidad Nacional de San Luis & CONICET, San Luis, Argentina

Vegetation changes, particularly those involving transitions between tree- and grass-dominated systems can have a strong influence on two central aspects of ecosystem functioning: evaporative water losses and base cation cycling. Existing tree plantations (fast growing pines and eucalypts) established on native grasslands are used as large scale experiments to evaluate the role of these plant-level contrasts shaping the hydrology and soil/water chemistry of whole ecosystems. A global synthesis of stream flow studies suggests higher evapotranspiration in afforested watersheds (an extra 15% of precipitation is evaporated) compared to adjacent grasslands. A similar synthesis for paired soil studies reveals a widespread soil acidification (a decline of 0.5 pH units) in afforested stands associated with exchangeable Ca reductions. This seminar considers connections between soil and hydrological alterations across a network of tree plantations in the grasslands of Argentina and Uruguay, and Vegetation to water to soil influences on flat landscapes of the Pampas, where tree plantations initiate a discharge regime in areas that functioned as recharge zones prior to tree establishment.

In these situations hydraulic alteration on the phreatic aquifer result in the discharge of shallow and young waters with high bicarbonate content in the edge of tree plantations and deeper and older waters with low bicarbonate content towards their core. These hydrochemical contrasts result in highly saline and alkaline soils in the borders of tree plantations and saline but neutral soils in their core. Vegetation ? soil ? water influences are illustrated with a series of small watersheds occupied by tree plantations and native grasslands in the hills of Cordoba and Lavalleja. There, the acidifying effect of tree plantations observed in soils globally seems to translate into stream acidification accompanied by declining concentrations of base cations and dissolved inorganic carbon and increasing concentrations of dissolved aluminum. These results highlight a) the important role of vegetation change shaping soils and water resources, b) the interactive nature of the biogeochemical and hydrological effects of vegetation. Besides being a valuable ecological experiment, tree plantations in grasslands are a major and accelerating “real world” land use change in Southern South America that poses multiple strains to local ecosystems and societies. The ecological and socioeconomic drivers of this land use are introduced and the role of science favoring its monitoring and sustainable implementation is discussed based on examples from the Pampas.

Esteban Jobbágy obtained his degree of Agronomist from University of Buenos Aires in 1993 and his Ph.D. in Biology from Duke University in 2002. He works as a Research Scientist (CONICET) in the University of San Luis, Argentina, and as Research Associate at Duke. His past work has involved the understanding of the patterns and controls of primary production in Patagonia and Southern South America using field and remote sensing observations, the analysis of ecological convergence in temperate zones at both sides of the the equator using floristic and biogeographical information, the synthesis of the vertical distribution of carbon and nutrients in based on global databases among other aspects of terrestrial ecosystem. In the last four years he has focused on the role of plants controlling soil and groundwater chemistry and hydrology, using man-induced vegetation changes as a study system, particularly tree plantation established in grassland ecosystems.

A complementary research line involves the design and development of alternative forestry systems for grassland regions. In 2004 he has founded “Grupo de Estudios Ambientales” in the University of San Luis. There, a team of Physicist, Biologists, and Agronomists are developing the fields of Biogeochemistry and Ecohydrology through research and education. From San Luis, Esteban is currently coordinating a network of global change scientist in the Plata Basin including institutions from Brazil, Uruguay, Paraguay, Argentina, and the US. This network is exploring the biophysical and human drivers and consequences of land use shifts in an attempt to generate basic understanding of global change processes as well as ecosystem management tools for the basin.

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Thursday Nov 3
A158 LSRC
4:00 - 5:15

New insights into the carbon cycle of Amazonia from a forest plot network
Yadvinder Mahli,Oxford University Centre for the Environment, and Research Fellow at the Institute of Ecology and Resource Management, University of Edinburgh

The Amazon rainforest biome plays a major role in the global carbon cycle. Hitherto, much research into the carbon cycling of intact Amazon forests has focussed on a few intensive field sites in Brazilian Amazonia. Here I present results from a forest plot network, RAINFOR, that has compared tropical forest dynamics across seven Amazonian countries. Amongst our key discoveries have been:

1. There are large and coherent regional gradients in the wood productivity of lowland Amazonian forests, with forests in western Amazonia being two to three times more productive than those in the east. These gradients appear to be driven by soil quality rather than climate, with soils in western Amazonia being younger and less weathered.
2. These variations in productivity have an effect on forest structure, with the dynamic western forests being dominated by fast-growing, short-lived, low wood density species, and the slow eastern Amazonian forests being dominated by slow-growing, long-lived, high wood density species. These contrasts result in mean wood density being 10 % higher in eastern Amazonia.
3. The stem volume of Amazon forests shows no regional variation in moderately wet to very wet forests, but declines in seasonally dry forests at the fringes of Amazonia.
4. The biomass of Amazonian forests peaks in central Amazonia and the Guyanas. It declines on the dry fringes because of reduction in stem volume, and declines in western Amazonia because of the decline in wood density.
5. The tree diversity of lowland Amazonian forests is strongly limited by the length of the annual dry season.
6. The productivity and diversity of Amazonian forests are driven by different environmental factors, and there is no simple relationship between the two.
7. There is evidence that the dynamics of Amazonian forests have accelerated in recent decades, with the greatest acceleration on the already dynamic forests of western Amazonia. The cause of this accelation is not yet clear, but it is plausible that global atmospheric change plays a major role.

Dr Yadvinder Malhi’s research focuses on how the physiology, structure, biomass and dynamics of tropical forests are controlled by climate and soils, and how these features of the forest may respond to ongoing atmospheric change. He is co-founder of the RAINFOR project, which has conducted systematic research in tropical forests across South America and Africa, and coordinator of the EU-funded training programme PAN-AMAZONIA (Project for the Advancement of Networked Science in Amazonia), which aims to train students from across Amazonia in ecological field science techniques. Mahli is co-editor of the book Tropical Forests and Global Atmospheric Change (Y. Malhi and O.L. Phillips, Oxford University Press, published July 2004). He has an undergraduate degree in Natural Sciences from the University of Cambridge, and a PhD in Meteorology from the University of Reading. His research interest in tropical forests began as a post-doctoral researcher at the University of Edinburgh, and he has been a Royal Society University Research Fellow since 1999. He is currently based at the Oxford University Centre for the Environment, and he is also an Honorary Research Fellow at the University of Edinburgh

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Monday, Nov 21
A158 LSRC
4:00 - 5:15

Aerosol effects on climate: Does strong aerosol cooling in the past imply a hotter future?
Meinrat Andreae, Max Planck Institute for Chemistry, Germany

Meinrat Andreae is director of the biogeochemistry department at the Max Plank Institute for Chemistry (MPIC), located in Mainz, Germany. As a child, Andreae enjoyed reading about chemistry and playing with chemistry sets. In college, he had planned to major in chemistry, but found its study too remote from direct applications to the Earth. Andreae instead switched his focus to geochemistry, and he earned a Vordiplom (B.S.) in Earth sciences from the University of Karlsruhe, Germany, in 1970. In 1974, Andreae went on to earn his Diploma (M.S.) in Earth sciences from Germany’s University of Göttingen. His thesis focused on the isotope and element geochemistry of rocks in southern Norway. Through this work, he became interested in biogeochemistry. “These were old, metamorphosed rocks, once exposed to extremely high temperatures and pressures deep in the Earth’s crust,” he recalled. “But there were signs that they formed by biological processes.” Building on these interests, Andreae earned his Ph.D. in 1978 from the Scripps Institution of Oceanography in San Diego, Calif., where he studied ocean and terrestrial biosphere interactions. After graduating, he served as a professor of oceanography at Florida State University, and, in 1987, became a professor at the MPIC. In 1988, Andreae received the World Meteorological Organization’s Gerbier-Mumm award for his discovery of a feedback loop between marine phytoplankton activity and global climate. In addition to studying the role of marine biota as a source of climatically important trace gases, Andreae is interested in the sources and characteristics of atmospheric aerosols and their effects on precipitation and climate, and the effect of vegetation fires on ecology and atmospheric pollution. Through his research, Andreae has traveled to the Amazon basin, the jungles of central Africa, and, most recently, Siberia and China, where he is investigating the effect of atmospheric pollutants on climate systems. Andreae was named the editor of the AGU’s journal Global Biogeochemical Cycles last year.
(excerpted from EOS, November 1, 2005 issue)

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SPRING 2005

Thursday, February 17
A158, LSRC
4:00 - 5:15

Selective Logging in the Brazilian Amazon: Biogeochemical Effects and Quantitative Damage Estimation Using Satellite Remote Sensing.
Michael Keller, Project Scientist for the Large-scale Biosphere Atmosphere (LBA) Experiment in Amazonia; USDA Forest Service, Intn'l Inst. of Tropical Forestry; and Professor at University of New Hampshire

Selective logging is an extensive land use in the Brazilian Amazon. Current estimates from economic data suggest that logging annually effects between 10,000 to 20,000 km2. Logging results in extensive damage to forest structure leading to changes in the forest carbon cycle and productivity. Forest productivity and the sustainability of logging depend greatly on the logging techniques employed. For years it has been shown that logging areas can be identified through satellite remote sensing. However, only recently, we have shown that using Landsat data together with extensive and detailed ground based measurements, forest damage can be quantified by spectral un-mixing of remotely sensed images. The combination of in situ and remote sensing studies provides a path to quantify logging effects on the Amazon region carbon cycle.

Michael Keller studies tropical forest ecosystems and the effects of land use change and agricultural intensification in Central and South America on the function of ecosystems and the control of atmospheric chemistry and composition. Keller’s research ranges from the biological controls of trace gas emissions at the organismal level to the estimation and modeling of regional and global trace gas and carbon budgets. Over the past two decades, he has lived and worked in Brazil, Panama, Costa Rica, and Puerto Rico as well as in the United States. He currently serves as lead scientist for the NASA sponsored LBA-ECO component of the Brazilian led Large Scale Biosphere Atmosphere in Amazonia (LBA) and the Co-Chair of the LBA International Science Steering Committee. LBA-ECO is designed around the question “How do tropical forest conversion, re-growth, and selective logging influence carbon storage, nutrient dynamics, trace gas fluxes and the prospect for sustainable land use in the Amazon region?” To answer this question Keller and his colleagues in LBA-ECO combine in situ measurements with regional models and remotely sensed observations of biological and social systems in the Amazonian environment.

Michael Keller is currently employed as a Research Scientist at the USDA Forest Service International Institute of Tropical Forestry in San Juan, Puerto Rico. He is stationed at the University of New Hampshire in Durham, NH where he is also an Affiliate Professor. Keller earned his B.A. in Geology at Harvard University and his Ph.D. in Geological and Geophysical Sciences at Princeton University.

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Thursday, March 24
113 BIOSCI 4:15 - 5:30 -- Note place and time

The role of terrestrial ecosystem processes in determining patterns of terrestrial carbon fluxes and atmospheric CO₂ concentrations: Results from a regional-scale coupled atmosphere-ecosystem model
Paul Moorcroft, Dept. of Organismic & Evolutionary Biology, Harvard University

Inverse studies of the carbon cycle have traditionally relied on low-frequency flask measurements collected at remote stations specifically located to eliminate variance in CO₂ concentrations arising from terrestrial processes. The insensitivity of these observations to terrestrial CO₂ fluxes makes it difficult to infer regional terrestrial carbon fluxes or to attribute large-scale fluxes to particular causes such as climate variability, land-use change or CO₂ fertilization. We are addressing this issue by developing a constrained implementation of the Regional Atmospheric Modeling System-Ecosystem Demography Model Version 2 (RAMS- ED2) for the New England region. RAMS-ED2 is a new, coupled atmosphere-ecosystem model that naturally scales between the fast timescale responses of individual plants to the atmosphere and the long-term, regional-scale dynamics of heterogeneous ecosystems subject to land-use change and forest harvesting. The model is designed to predict carbon fluxes on spatial scales from hectares to thousands of square kilometers that are consistent with fast timescale flux-tower measurements of CO₂ fluxes, seasonal measurements of canopy phenology from remote sensing data and decadal scale forest inventory measurements and land-use history forcing. The ecosystem state variables and environmental response functions of the optimized model provide a comprehensive description of short and long term factors regulating fluxes in the regional carbon cycle. The optimized model will provide a unique tool for quantifying the contributions of environmental forcing, ecosystem recovery from land-use change, forest harvesting and CO₂ fertilization to current and future patterns of terrestrial carbon fluxes and resulting patterns of atmospheric CO₂ concentrations in North America.

Paul Moorcroft is an Assistant Professor of Ecology at Harvard University who specializes in terrestrial ecosystem dynamics. His research investigates how ecological processes affect the structure, composition, and biophysical and biogeochemical functioning of terrestrial ecosystems at regional to global scales. Professor Moorcroft received his undergraduate degree from Cambridge University, and his doctorate from the Department of Ecology and Evolutionary Biology at Princeton University. After spending three years as postdoctoral researcher at the Princeton Environmental Institute, he joined the Harvard faculty in 2001.

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Tuesday, April 5
A158, LSRC
4:00 - 5:15

Climate Change in the U.S. Congress: An Update on Congressional Action and How Science Informs (or Doesn't Inform) the Debate
Manik Roy, Ph.D., Director of Congressional Outreach, Pew Center on Global Climate Change

Five years ago, there was virtually no action in the United States Congress on global climate change. Three years ago, the U.S. Senate passed a bill to have the largest emitters of greenhouse gases (GHG) track and disclose their emissions. A year-and-a-half ago, 44 senators supported a Lieberman-McCain bill to cap U.S. GHG emissions. Today, several conservative Republican senators are for the first time urging action to address climate change. Why the recent burst (by congressional standards) of activity? What policy options are being discussed? Where is the U.S. House of Representatives in all this? How is science used (and abused) in the debate?

Manik Roy is the Director of Congressional Affairs for the Pew Center on Global Climate Change, where he manages communication between the Center and the United States Congress. Dr. Roy has had twenty-two years of experience in environmental policy, working most recently for Senator Frank R. Lautenberg and Representative Henry A. Waxman. Prior to working in Congress, Dr. Roy was the director of the pollution prevention policy staff of the U.S. Environmental Protection Agency, and a pollution prevention specialist with the Massachusetts Department of Environmental Protection and the Environmental Defense Fund. Dr. Roy holds a Ph.D. in public policy from Harvard University. He also holds a Master of Science degree in environmental engineering and a Bachelor of Science degree in civil engineering, both from Stanford University.

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Thursday, April 7
LSRC A158
4:00 - 5:15

Putting a Human Face on Science (Getting Media Attention for Environmental Topics)
Michael Tennesen, 2nd CGC Writer in Residence & Nicholas School Environmental Media Fellow

A science and nature writer, Tennesen has written more than 400 stories in such publications as Smithsonian, National Wildlife, Audubon, Wildlife Conservation,Air and Space, and Discover. He wrote Flight of the Falcon for Key Porter Books (1994) and is the author of The Complete Idiot's Guide to Global Warming (2004).
Michael Tennesen is a graduate of the University of California at Los Angeles and has been a full time freelance journalist for better than 20 years.

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Thursday, April 21
A158, LSRC
4:00 – 5:15pm

Catchment (water shed) hydrology research in South Africa: past, present and future
David Le Maitre, Conservation Biologist–Hydrologist, Environmentek, Council for Scientific and Industrial Research (CSIR), Pretoria, South Africa

South Africa is a semi-arid country with a mean annual rainfall of about 450 mm compared with a world average of about 860 mm. Almost 60% of the country gets less than 500 mm per year and only 12% more than 750 mm. Only 9% of the rainfall ends up in the streams and rivers as surface runoff. This is far lower than the world mean value of 34% but similar to that of Australia and Zimbabwe. Less than 0.5% of the country is covered in indigenous closed forest. The shortage of suitable timber for construction and other purposes was recognised in the mid 19th century and this realisation led to the progressive afforestation of areas with pines, eucalypts and Australian acacias. This afforestation programme was controversial because many farmers and scientists argued that replacement of native vegetation (shrubland, grassland) with plantations reduced the amount of water in streams draining those catchments. Others argued that afforestation would trap more moisture from the air and increase flows. A forest hydrology research programme was launched in the 1930s to address this controversy and has continued at various levels of intensity to this day. This research shows conclusively that afforestation reduces the surface runoff, a finding which is in line with research in other countries. The idea that forests bring more water still has strong support, at least in much of Africa. This can be explained by changes in infiltration and seasonality of flows following land degradation, and a model is proposed to explain this conundrum.
The reductions in surface runoff are very important because plantations typically are situated in the high rainfall regions and high yielding catchment areas of the country. Currently, plantations account for an incremental loss (relative to the natural vegetation) of about 3.5% of the annual surface runoff although they occupy only 1.3% (1.5 million ha) of the country. This research is continuing and has been extended using techniques such as tree sap-flow and micrometeorology (e.g. energy balance) to estimate evaporation and soil moisture balance and flux at the hillslope scale.
The results of the catchment-scale hydrological research provided the basis for introducing legislative control over afforestation in 1972 and under new the National Water Act (1998) as a “stream flow reduction activity”. The research findings were also used to estimate the impacts of invasions by woody introduced species on surface runoff in South Africa. A crude model was developed to estimate the impacts of these invasions. This gave an estimate that (when the total invaded area of 10.1 million ha was adjusted to its equivalent area with 100% canopy cover, namely 1.7 million ha) invasions have reduced mean annual runoff by 6.7%. These findings have been used to support a national weed clearing programme (Working for Water) which is currently running on an annual budget of USD 60 million.
The predicted impacts of climate change in South Africa are drastic. Vegetation studies indicate that most of the western regions will become semi-desert. There will be relatively little change in the eastern regions but there are substantial uncertainties. A research project aimed at assessing the hydrological implications of the predicted climate has just been launched. The long-term records from the research catchments also provide a unique, continuous record of rainfall and runoff which spans a period of nearly 70 years which can be used in this assessment. An initial analysis of these records indicate that there may be a decline in rainfall, and thus in the runoff, in these critical catchments but further, more detailed assessments are needed.

Dr David Le Maitre has a Ph.D. in plant ecology and is a conservation biologist and hydrologist, employed by the South African Forestry Research Institute (Department of Water Affairs and Forestry) from 1979-1990 and by the CSIR (a statutory research council) since 1990. He has more than 20 years of research experience in the ecology of Cape fynbos vegetation and also has been involved for more than 10 years in research on the impacts of plantations and alien plant species on water resources and ecosystems. He has developed expertise in assessing the hydrological and ecological impacts of invading alien plants and the dynamics of invasion processes. He has a special interest in the ecological role of groundwater, particularly in groundwater-dependent ecosystems. He has also been involved in the assessment, maintenance and conservation of biodiversity, particularly the development and use of indicators. He has published widely in the scientific literature, especially in the field of the fire-related ecology of fynbos and the hydrological impacts of alien plant invasions. He has played key roles in developing:
• Guidelines and tools for identifying groundwater-dependent ecosystems and assessing the groundwater Reserve (South African National Water Act).
• Development of monitoring systems for assessing the impact of city-scale groundwater abstraction in the Cape Table Mountain Group aquifer.
• Approaches for modelling the impacts on invasive plant species on water resources for medium-scale catchment (basin) water supply scheme analyses.
• An analysis of the impacts of plantations on surface water resources (for the national Department of Water Affairs & Forestry).
• An assessment of extent and impacts of alien plants on water resources in South Africa (Water Research Commission for the Working for Water Programme).
• Formulation of a research programme for groundwater-vegetation interactions (Water Research Commission).

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Tuesday, May 3 -- CANCELLED
Location: TBA
4:00 - 5:15

Looking for carbon in all the wrong places: Carbon dynamics in the Rocky Mountains
Dave Schimel, Senior Scientist, Terrestrial Sciences, Climate and Global Dynamics Division, National Center for Atmpospheric Research

Analysis of satellite data and simulation models clearly shows that a disproportionate share of US carbon uptake takes place in mountains, where now-traditional micrometeorological and airborne techniques are widely assumed to be unusable. We conducted an integrated surface, airborne and modeling analysis of carbon fluxes in the Rocky Mountains, first to develop techniques for scaling carbon fluxes in extreme complex terrain, and second to confirm indirect estimates suggesting active carbon storage. The results show that meteorological techniques can be applied in the mountains, and that respiration fluxes that are challenging to quantify in conventional sites can be estimated at large scales in the mountains. Airborne budgets provide a useful complement to surface observations, increasing the value of both. Even airborne snapshots provide a powerful view of the seasonal cycle at the regional scale. We show an assimilation-model based breakdown of eddy covariance fluxes into photosynthesis, autotrophic and heterotrophic respiration and NPP and use this as a basis for hypotheses about the relationship between truly regional satellite-constrained estimates of photosynthesis and similarly scaled airborne estimates of net ecosystem exchange. Overall, while no single method provides all the desired regional information, the synthesis of methods provides a nearly comprehensive view.

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Thursday, June 23
A247 LSRC
4:00 pm -- 5:15pm

Grassland afforestation effects on water and salts dynamics
Marcelo Nosetto, Grupo de Estudios Ambientales – IMASL, Universidad Nacional de San Luis & CONICET San Luis, Argentina.

Vegetation changes, particularly those involving transitions between tree- and grass-dominated covers, can modify evaporative water losses and, as a consequence, salt accumulation patterns. Water use in /Eucalyptus grandis/ plantations and the native humid grasslands that they replace in Central Argentina were explored using a remote sensing approach, suggesting an almost two-fold raise of evaporative water losses in afforested areas. Afforested stands used more water both in dry and wet periods indicating both, better access to water sources and higher evaporative capacity. Salt distributions patterns in soils occupied by tree plantations and native grasslands were examined in the Argentinean Pampas and the Hungarian Hortobagy. Both regions displayed large salt accumulation in the vadose zones of afforested areas suggesting that trees, through groundwater consumption and solute exclusion, triggered a salinization process in deep soil layers. However, lower salt concentration observed in shallow soil layers in Hortobagy under tree plantations indicate that trees in that region may have also enhanced water infiltration. Highly promoted as a carbon sequestration means, tree plantations in grassland ecosystems could have a strong impact on the hydrological cycle with cascading effects on salts dynamics.

Marcelo Nosetto is a graduate student working in “Grupo de Estudios Ambientales” in the University of San Luis in Argentina. His work involves the exploration of land use changes impacts on ecosystem function, specifically afforestation in grassland ecosystems. He uses a combination of plot, catchments and remote sensing approaches to uncover the effects of this land-use shift on water, carbon and salts dynamics. He is participating in several projects related to land-use change and its effects on ecosystem functioning and regional climate, which involve collaborations with researchers at Duke University (Jackson lab), Hungary and Uruguay.

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FALL 2004

Thursday, September 9
A158, LSRC
4:00 - 5:15

Forest Responses to Elevated Atmospheric CO₂: Contrasting Patterns of Carbon Allocation in Oak Ridge and Duke FACE Experiments
Richard J. Norby, Oak Ridge National Laboratory

The Free-Air CO₂ Enrichment (FACE) experiment at the Oak Ridge National Laboratory provides a valuable opportunity to compare the responses of a deciduous sweetgum forest with those of the evergreen pine forest in the Duke FACE experiment. The Oak Ridge FACE experiment is in a closed-canopy stand of sweetgum (Liquidambar styraciflua) trees on the Oak Ridge National Environmental Research Park. The trees have been exposed since 1998 to elevated CO₂ in two 25-m diameter plots using similar technology to that used in the Duke FACE experiment. Net primary productivity (NPP) is measured through allometric analysis of stem growth, weighing of leaf litter, and minirhizotron analysis of fine root production. NPP has been higher each year in plots with 550 ppm CO₂ compared to plots in ambient air. The average increase has been 22%, and there is no indication of a loss in response over time. Annual production of fine roots was more than doubled in CO₂-enriched plots, and this response was the primary component of the increase in NPP. Aboveground wood production, however, increased significantly only during the first year of treatment. The allocation pattern is the primary difference between the response of this deciduous stand and that of the loblolly pine stand in the Duke FACE experiment. NPP of the pine stand has been stimulated by elevated CO₂, and the stimulation has persisted through time, but the extra C has been recovered in stems, not in root production. This difference in allocation pattern has important implications for biogeochemical cycling, including the potential for these forests to sequester C. The preferential allocation of additional carbon to fine roots, which have a fast turnover rate in this species, rather than to stemwood, reduces the possibility of long-term enhancement by elevated CO₂ of carbon sequestration in biomass. However, sequestration of some of the fine root carbon in soil pools is not precluded, and there may be other benefits to the tree from a seasonally larger and deeper fine root system. The contrasting responses of the forest stands in the FACE experiments at Oak Ridge and Duke demonstrate the importance of understanding C allocation patterns and tissue turnover rates as determinants of ecosystem response to elevated atmospheric CO₂.

Richard Norby is a Distinguished Research Scientist in the Environmental Sciences Division at the Oak Ridge National Laboratory (ORNL), where he has worked since 1981. He received his education at Carleton College with a B.A. in chemistry awarded in 1972, and at the University of Wisconsin-Madison, where he received a Ph.D. in forestry and botany in 1981. His research interests include tree physiology, forest ecology, and global change. Norby has been conducting experiments on the effects of rising atmospheric CO₂ concentrations on forest tree species since 1982. He is the principal investigator of the Oak Ridge Experiment on CO₂ Enrichment of Sweetgum, in which a closed-canopy deciduous forest is being exposed to elevated CO₂ using free-air CO₂ enrichment (FACE) technology. He also leads an ongoing experiment investigating the interactions between CO₂, warming, and soil moisture in an old-field community. Norby was a task leader for CO₂ research within the Global Change and Terrestrial Ecosystems core project of the International Geosphere-Biosphere Programme, and he also serves as a Environment Section editor of New Phytologist. He received the Scientific Achievement Award of the Environmental Sciences Division in 1992 and was elected fellow of the American Association for the Advancement of Science on 1995. A complete CV may be found at http://www.ornl.gov/~rjn.

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Thursday, November 4
A158, LSRC
4:00 - 5:15

Linking genome, physiological, and ecosystem responses to rainfall variability in a mesic grassland
Phil Fay, University of Minnesota, Duluth, Natural Resources Research Institute, Center for Water and the Environment

The Rainfall Manipulation Plot Experiment (RaMPs) is an ongoing multi-factor climate change experiment at the Konza Prairie Biological Station in northeastern Kansas - that implements forecast changes in temperature and rainfall patterns associated with energy production and consumption on a native grassland ecosystem. The RaMPs experimental infrastructure examines two key, predicted environmental changes: 1) increased temperature (1-2°C), and 2) more variable precipitation regimes, specifically increased time between rainfall events and events of greater intensity. It is an ideal platform for this research since most of the relevant organismic-through-ecosystem responses to climate change have been characterized over the last 6+ years, with monitoring still ongoing. After 6 years of experimentally increased rainfall variability, we have observed impacts at multiple levels of biological organization. These include lower mean and increased variability in soil moisture, decreased aboveground net primary production and soil CO₂ flux, both of which will have important implications for C storage and cycling over the long term. Recent results from the RaMPs has demonstrate that genomic data can be collected from plants under field conditions and directly linked to plant physiological responses underlying climate change impacts on ecosystem structure and function. Our immediate goals are to conduct detailed, spatially and temporally explicit genomic sampling in concert with leaf level physiological measurements on two dominant C4 grasses in this ecosystem, and then scale these to the emergent community and ecosystem level responses based on differential responses of the individual species. The research will bridge a fundamental divide between two disciplines in biology traditionally focusing on divergent domains of inference, strengthening both fields by developing and testing a novel, integrative approach, thereby providing the knowledge necessary to plan mitigation and policy for the climatic alterations facing society.

Dr. Fay is a Research Associate at the Natural Resources Research Institute. His research interests span ecosystem, plant population and physiological ecology, and plant/animal interactions in grassland ecosystems. He uses a combination of laboratory, greenhouse and large scale field manipulations to determine the role of climatic variability and extreme climatic events in structuring grassland ecosystems. His main projects involve field scale manipulations of rainfall inputs and temperature in native tallgrass prairie at the Konza LTER site, and new or developing projects will focus on linkages between the plant genome and ecosystem properties, and regional variation in ecosystem responses to climate variability. His work has been supported by NSF, USDA, and DOE, and appeared in numerous international journals.

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Thursday, November 11
A158, LSRC
4:00 - 5:15

The Importance of Comparing Apples to Apples: Matching MODIS to Flux Towers
Hans Peter Schmid, Department of Geography, Atmospheric Science, Indiana University, Bloomington; Director of the Institute for Research in Environmental Science

Satellite derived estimates of ecosystem-atmosphere carbon exchange have the advantage of global coverage, but need to be verified by in-situ flux measurements at flux towers. This work addresses problems and issues associated with matching MODIS products to flux tower derived gross photosynthetic exchange of carbon dioxide (GPE) at the hand of 7 km x 7 km MODIS product subsets centered on the AmeriFlux tower in Indiana (MMSF~flux). The principal concerns here are that (i) the footprint of turbulent flux measurements is typically considerably smaller than a 1 km square MODIS pixel, (ii) that the flux footprint is non-stationary and varies its size and location according to the flow and turbulence conditions in the atmospheric boundary layer, and (iii) that MODIS products of GPE are typically 8-day composites derived from eight or less valid satellite passes and simulated meteorological conditions.

To shed light on these issues, high resolution LAI (derived from Ikonos and Landsat/ETM+ satellites) will be overlaid with computed flux footprints to examine the area-to-area representativeness of flux measurements over various time scales. In particular, we will examine whether the averaging power of the spatially evolving flux footprint over an 8-day integration period (matching the MODIS time scale) is usually sufficient to provide fluxes with acceptable spatial representativeness to serve as a benchmark for MODIS products. We compare eight-day composites of MODIS and tower fluxes, using simulated and locally measured meteorological information, and relate the comparison to measures of spatial representativeness of the flux measurements.

Hans Peter Schmid is Associate Professor in the Atmospheric Science Program of the Department of Geography at Indiana University, Bloomington. His research interests includes biosphere-atmosphere interactions, the atmospheric boundary layer and micrometeorology over inhomogeneous surfaces. His specialty is footprint modeling and the development of objective methods to scale-up from footprint to ecosystem fluxes. Dr. Schmid is co-Director of IU's Institute for Research in Environmental Science (IRES). He received his Ph.D. from the University of British Columbia in Geography and Atmospheric Science.

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Tuesday, November 16
4:00—6:00pm, Law School, Rm 3043
Webcast now available >

Can Markets Protect the Climate? Prospects for Greenhouse Gas Emissions Trading in the US and Europe
click for detailed symposium information >

Speakers:
Peter Zapfel, European Commission, Directorate General - Environment (abstract & bio > | presentation >)
Tim Profeta, JD-MEM, Duke Law and Nicholas School, '97, currently counsel to Senator Joseph Lieberman (bio > | presentation >)

Discussants:
Joseph Goffman, Attorney, formerly at Environmental Defense (bio >)
Bruce Braine, Vice President, Strategic Policy Analysis, American Electric Power (bio > | presentation >)

Moderator:
Jonathan Wiener, Professor of Law and Environmental Policy and Director, Center for Environmental Solutions

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Tuesday, November 30
A158, LSRC
4:00 - 5:15

Projecting climate change impacts on species and ecosystems: Perspectives from the southern Hemisphere
Guy F Midgley, Climate Change Research Group, South African National Biodiversity Institute, Cape Town, South Africa.

Obvious differences in the latitudinal distribution of continental land mass between the southern and northern hemispheres seems at least partly responsible for some interesting contrasts in emphasis in ecological thinking among terrestrial ecologists of the two hemispheres. In particular, disturbance by fire and drought have attracted relatively more attention in the south, due to the prevalence of flammable subtropical and temperate ecosystems, drought-prone arid- and semi-arid ecosystems, and the influence of ENSO-related climate phenomena. These preoccupations are also reflected in thinking about anthropogenic climate change impacts, and I will discuss some of the insights that are emerging from this perspective, using mainly southern African examples.

Dr. Midgley is a plant physiologist and specialist scientist at the National Botanical Institute (NBI), now South African National Biodiversity Institute, in Cape Town, SA. He is involved in multiple projects related to climate change, including lead scientist of a group that is investigating the effects of rising temperatures on the Karoo flora; primarily funded by Conservation International. See: http://www.nbi.ac.za/homepage.htm, “Effects of CO₂ on natural vegetation in South Africa”. See also this review of climate change impacts, “In a Nutshell”, based on research by Dr. Midgley, and others : http://www.nbi.ac.za/frames/researchfram.htm/.

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SPRING 2004

Friday, February 13
A158, LSRC
4:00 - 5:15

Causes and Consequences of Plant Functional Diversity: Biotic Effects on Ecosystem Processes and Responses to Global Change
Peter B. Reich, F.B. Hubachek Sr. Chair (in Forest Ecology and Tree Physiology) and Distinguished McKnight University Professor in the College of Natural Resources at the University of Minnesota.

Why aren’t all plants the same? How and why are they different, how and why are they not different, and what are the implications for communities and ecosystems, especially in the face of global change? In this talk, we will visit the concept of plant traits and their relationships, asking to what degree leaf traits are driven by natural selection and biophysics into the same constellations world-wide, and whether this gives us clues to help us generalize about the ways in which plants influence their communities and ecosystems? In doing so, I will present new data from a study of 2,300 species at 175 sites around the world, and also present results from several site-based studies that show how plants radically influence soils much faster than is typically appreciated. Finally I will discuss how both divergence among and diversity of traits may influence terrestrial ecosystem response to global environmental change, such as in CO₂, N deposition, and temperature.

Dr. Reich is an ecologist interested in global change and the sustainability of managed and unmanaged terrestrial ecosystems. His work includes a range of studies from scaling relationships across organizational, temporal and spatial gradients, to an integrated focus on mechanisms linking ecophysiology, community dynamics and ecosystem processes. He is active in an array of research activities that range from an open-air multi-factor experiment with elevated carbon dioxide in grasslands; to studies of boreal forest sustainability in the face of fire suppression, logging, and climate change; to leading an international consortium to develop a global plant ecophysiological data base.

Professor Reich has written more than 200 articles published in peer-reviewed international scientific journals or books; and has been engaged in research in tropical, temperate and boreal ecosystems on five continents. He has served on the editorial boards of leading international journals, and received numerous honors, such as the Pound Research Award (University of Wisconsin), the Presidential Young Investigator Award (National Science Foundation), and the Distinguished McKnight University Professorship (University of Minnesota). Professor Reich received a B.A. from Goddard College in Vermont with a major in physics and creative writing, an M.S. in forest ecology from the University of Missouri, and a Ph.D. in environmental biology from Cornell University. He joined the faculty of the University of Minnesota in 1991.

This seminar is co-sponsored by the Biology Department and the Duke University Program in Ecology (UPE).

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Thursday, February 19
A158, LSRC
4:00 - 5:15

Global Change and Ecosystem Models: Problems, Products and Potential
Dr. Steven McNulty, USDA Forest Service, Southern Global Change Program, Raleigh, NC

Global change is a general term for atmospheric (including climate, ozone, CO₂, and nitrogen deposition) and landuse use change. There has been increasing interest regarding potential global change impacts on people and the environment (including forests) since the early 1990’s. However, there are two serious impediments in studying global change impacts on forest ecosystems. First, it is nearly impossible to gain consensus on the degree and rate that global change is occurring because there are so many environmental, economic, and political factors driving the change. Second, it is financially and logistically impossible to devise an experiment that can simultaneously test all of the factors controlling and impacted by global change. For example, synergist relationships between global change drivers and natural resource areas are to be expected but are not implicit. Therefore, individual components of global change are studied at a fine spatial resolution, and models are used to integrate; 1) multiple atmospheric changes with multiple ecosystem processes such as forest growth, mortality, regeneration, and water use; 2) economic impacts both within the forest sector and between other economic sectors; and 3) across spatial and temporal scales. I will begin the presentation by addressing some of the major problems associated with assessing multiple co-occurring global change impacts on forest ecosystems. Next, I will present some of the latest results and maps of regionally integrated global change models predictions on current and future forest ecosystem productivity, biodiversity, water use, economic value, and resource availability. Then I will conclude the presentation with some thoughts on the likely future directions in global change study, modeling and assessment.

Steven McNulty has authored or co-authored over 75 papers associated with climate change, wildfire, human population change, ozone, atmospheric CO₂ change, and nitrogen deposition impacts on forest ecosystem structure and function. His research focuses on regional to continental scale integrated modeling of environmental stress impacts on forest productivity, hydrology, He has served as the Manager and Project Leader of the USDA Forest Service’s Raleigh based, Southern Global Change Program (SGCP) since 1996, and he has a Joint USDA Faculty Appointment with NCSU, and adjunct faculty appointments with Beijing Forestry University and the University of Toledo. He received a B.S. and M.S degrees in Natural Resources from the UW Madison, and a Ph.D. (1991) in Natural Resources from UNH. Dr. McNulty served as a US Congressional Fellow in the office of Charles Taylor (11th District, NC) during the 106th Congress (2002), the chair of the USDA National Symposiums on carbon sequestration (2000 and 2002), and the federal chair of the National Assessment of Climate Change Impacts on US Forests. Prior to joining the SGCP, he spent five years as a research ecologist with the USDA Forest Service, stationed at the Coweeta Hydrologic Laboratory.

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Thursday, March 4
A158, LSRC
4:00–5:15pm

Ocean-Atmosphere Interactions in the "Greenhouse" Climate of the Eocene and a comparison with other paleoclimates
Dr. Matthew Huber

Paleoclimatology can answer critical questions about climate and climate change. Most critically: What is the ‘‘natural,’’ unforced variability of the climate system? What are the responses of the system to known, external forcing? Interactions, between components of the Earth System, i.e. the ocean, atmosphere and biosphere, or between major modes of climate variability and the mean state, remain key areas of uncertainty in our understanding of climate dynamics. Past periods of extreme global warmth or cooling, exemplified by the Eocene (55-35 Mya) or Last Glacial Maximum (21 Kya), provide a test of theories for these interactions.

Variability, through its role in climate and in the detection of climate change, is currently the focus of much attention, partially because recognition of modern climate trends depends on characterizing modes of variability on decadal and longer times scale, and partially because nonlinear interaction between variability and the mean state may play a fundamental role in the evolution of the climate system. Paleoclimate records of interannual and lower frequency variability generated from, e.g., tree ring time series, coral isotopic variations or varved sediments, can directly supplement observational records where they are continuous and overlap or they can provide windows into the operation of the climate system in the deep past when the records are ‘‘floating’’ in time. Consequently, proxy-derived records for variability can play a pivotal role in identifying the stability of leading modes of variability and are also critical for constraining the relationship between global climate change and the spatial-temporal structure of these modes. The ability of the ocean-atmosphere system to transport heat poleward may be sensitive to changes in ocean-atmosphere interaction, including modes of interannual variability, as well as changes in boundary conditions, e.g. opening and closing of ocean gateways.

I present results comparing model predictions of modes of variability for the Eocene, Cretaceous, LGM, and modern, and explore how these predictions compare with those of theory and the implications for maintenance of the mean state in these simulations. I find that most modes of variability are quite robust to changes in boundary conditions, and that they likely played a role in the climates of the past, and by extension, are likely to play a significant role in the future. Controls on heat transport by the atmosphere and ocean are discussed and implications for the two climate dynamics paradigms, "polar amplification" and "tropical thermostating" are drawn.

Matthew Huber is a climate dynamicist interested in the physical and biogeochemical mechanisms that govern the major aspects of Earth's climate. He is currently an Assistant Professor in the Earth and Atmospheric Sciences Department at Purdue University. Huber received his BA in Geophysics from the University of Chicago in 1994, where he worked with R. T. Pierrehumbert studying the relative humidity distribution of the tropics. He investigated Lagrangian turbulence of the troposphere in the Atmospheric Sciences Department at UCLA while working with M. Ghil and J. C. McWilliams (MS, 1997). For his Ph.D., Huber worked with L. C. Sloan at UC Santa Cruz to gain a better understanding of the coupled ocean-atmosphere-sea ice system in the super 'greenhouse' Eocene climate, and to verify the predictions of a coupled climate model with paleoclimate proxies. In 2001, Huber moved to the Danish Center for Earth System Science at the Niels Bohr Institute in the University of Copenhagen, where he investigated the stability of modes of interannual variability in different climates and the causes of major climate transitions in the Cenozoic (such as the initiation of Antarctic glaciation).

Huber believes that most of our current understanding of climate is focused on modern processes and state parameters, and consequently our theoretical and numerical tools are essentially linearizations around a basic state that is unrealistically fixed. Huber hopes that a broader consideration of the history of climate and Earth System will enable a deeper understanding of the physics of climate. His current work focuses on the mechanisms that govern equator-to-pole and vertical temperature gradients in the atmosphere and ocean, the factors influencing the distribution of water vapor, clouds, and precipitation in the atmosphere, and the nonlinear interaction between the background state and variability in determining the dynamics and phenomenology of the system. Several of his current projects focus on controls on ocean heat transport and it's relationship interaction with the atmosphere, within paleoclimate contexts, and as constrained by paleoclimate proxies.

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Thursday, March 18
A158, LSRC
4:00–5:15pm
Co-sponsored by CGC and the Biology Superspeakers Program Series

How to Solve the Problem of Greenhouse Warming.
Dr. Steve Pacala

To solve the problem of greenhouse warming, humanity must stabilize atmospheric CO₂ at a level that would prevent serious damage to humans, human institutions and ecosystems. The widespread perception that the problem is intractable stems from an inappropriate focus on the period after the year 2050. We already possess cost-effective technology to limit the fossil fuel emissions over the next half century so that atmospheric CO₂ follows a trajectory leading to a safe maximum concentration.

Three questions will be addressed. How serious is the problem of greenhouse warming and what is a safe level for greenhouse gasses in the atmosphere? How much must emissions be reduced to achieve a safe stabilization target and how confidently can we compute the required cuts? How can we best achieve the required cuts through the year 2050? The majority of the talk will focus on the third question and will enumerate the technological options for reducing emissions that are already deployed at an industrial scale and have shown a capacity to grow market share rapidly.

There are six such options that would each be capable of supplying 1/7 of the required emissions reductions or more: carbon capture with geologic carbon sequestration, increased energy efficiency, renewable electricity and fuels, substitution of natural gas for coal, nuclear electricity and ecological carbon storage. All of these would need to be pursued simultaneously because it would be impossible (or at least very expensive) to grow any one fast enough, and because most would bring new environmental problems. New environmental problems include risks from CO₂ that leaks from sequestration sites, climate change from large-scale wind power, and decreased air quality from organic carbon emitted by plantation trees.

Dr. Stephen W. Pacala is the Frederick D. Petrie Professor of Ecology and Evolutionary Biology at Princeton University. He has researched problems in a wide variety of ecological and mathematical topics. These include the maintenance of biodiversity, the mathematics of scaling, ecosystem modeling, ecological statistics, the dynamics of vegetation, animal behavior, the stability of host-parasitoid interactions, the relationship between biodiversity on ecosystem function, and field studies of plants, lizards, birds, fish, insects, and parasites. Since moving to Princeton University, Dr. Pacala has focused on problems of global change with an emphasis on the biological regulation of greenhouse gases and climate. He currently directs the Princeton Carbon Mitigation Initiative.

Dr. Pacala completed an undergraduate degree in biology at Dartmouth College in 1978 and a Ph.D. in ecology at Stanford University in 1982. He was Assistant and Associate Professor at the University of Connecticut from 1982 to 1992, and then moved to Princeton University as Professor of Ecology in 1992. He was awarded the Frederick D. Petrie Chair in 2000. He has served on numerous editorial and advisory boards.

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Friday, March 19
Room 118, BIOSCI
Co-sponsored by CGC and the Biology Superspeakers Program Series
4:00 - 5:15

Forest Inventory Data Falsify Ecosystem Models of CO₂ Fertilization
Dr. Steve Pacala

We analyze tree growth data from Wisconsin forest inventories completed in 1968, 1983, 1996 and 2002. These show that the rate of forest growth decreased steadily over the period, in contrast to the increases predicted by CO₂ fertilization models. Measured growth rate changed an average of -0.27% y-1 (95% confidence range: -0.05% to -0.49% y-1), whereas the prediction for CO₂ fertilization is 0.16% y-1 (corresponding to a ß of 0.36). The high statistical precision is due both to large sample sizes and positive correlations among the growth rates from different time periods within the same plot. Decreased growth occurred in stands of all ages, and so our results are not caused by age-related declines in growth (although highly significant age-related declines were also detected).

Data allowing a direct examination of growth rates over several decades are available only for Wisconsin, but Caspersen et al. (2000) introduced an indirect method for detecting past changes in growth rate using only two sequential inventories. This method was criticized by Joos et al. (2002), who claimed that it lacked the statistical power to falsify state-of–the-art ecosystem models of CO₂ fertilization. We explain both the sound points and the critical errors in Joos et al.’s argument, introduce a transparent and analytically tractable version of Caspersen et al.’s method, and check its ability to detect the decreasing growth rates in the Wisconsin data. The results show that the indirect method accurately characterizes the past changes that actually occurred, and has sufficient statistical power to falsify CO₂ fertilization models, including the model in Joos et al. (2002).

We discuss the implications of decreasing Wisconsin growth rates, together with other reasons for skepticism about the future magnitude of CO₂ fertilization. In particular, the steep reductions in fossil fuel emissions required to stabilize atmospheric CO₂ at 500 ppm must begin more than a decade sooner if the predictions of the CO₂ fertilization models in the IPCC Third Assessment (Prentice et al. 2001) are incorrect. The difference between a terrestrial carbon sink that grows because of CO₂ fertilization, and one that shrinks because it is caused by recovery from past land use, is the difference between the luxury of a substantial delay and the need to act now.

Dr. Stephen W. Pacala is the Frederick D. Petrie Professor of Ecology and Evolutionary Biology at Princeton University. He has researched problems in a wide variety of ecological and mathematical topics. These include the maintenance of biodiversity, the mathematics of scaling, ecosystem modeling, ecological statistics, the dynamics of vegetation, animal behavior, the stability of host-parasitoid interactions, the relationship between biodiversity on ecosystem function, and field studies of plants, lizards, birds, fish, insects, and parasites. Since moving to Princeton University, Dr. Pacala has focused on problems of global change with an emphasis on the biological regulation of greenhouse gases and climate. He currently directs the Princeton Carbon Mitigation Initiative.  Dr. Pacala completed an undergraduate degree in biology at Dartmouth College in 1978 and a Ph.D. in ecology at Stanford University in 1982. He was Assistant and Associate Professor at the University of Connecticut from 1982 to 1992, and then moved to Princeton University as Professor of Ecology in 1992. He was awarded the Frederick D. Petrie Chair in 2000. He has served on numerous editorial and advisory boards.

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Wednesday, March 24
A158, LSRC
4:00 - 5:15

On the Coupled Geomorphological and Ecohydrological Organization of River Basins
Ignacio Rodriguez-Iturbe, Department of Civil and Environmental Engineering, Princeton University

Water balance at the daily level is used to link the observed patterns of basin organization to soil moisture dynamics. The co-organization of the spatial patterns of the soil moisture probabilistic parameters and the observed vegetation distribution is linked through the template of the drainage network. It is shown that such co-organization exhibits self-affine characteristics in their distribution across river basins.

Dr. Rodriguez-Iturbe received his undergraduate degree in Civil Engineering at Universidad del Zulia, 1963 ( Venezuela), his M.S. at the California Institute of Technology, 1965 (CA), and his Ph.D. at Colorado State University, 1967(CO). He has co-authored more than 150 peer-reviewed articles and 6 books--most recently a book with Amilcare Porporato on Ecohydrology. His articles have appeared in the most prestigious journals of hydrology, as well as such interdisciplinary journals as Science and Nature. His research in these publications has been highly regarded and widely cited, leading to honorary degrees from 21 universities, and more than 40 awards, including the Huber Research Prize by the American Society for Civil Engineers (1975), the Horton Research Award by the American Geophysical Union (1975), the James B. Macelwane Award by the American Geophysical Union (1977), and the Horton Medal by the American Geophysical Union (1998). Dr. Rodriguez-Iturbe is a member of the National Academy of Engineering (1988), he was recently awarded the Stockholm Water Prize (2002), the most prestigious price in Water Resources, and he also is listed among the ISIHighlyCited.com individuals in the area of Ecology/Environment.

This seminar is co-sponsored by the Department of Civil and Environmental Engineering, Duke University

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Thursday, April 8
A158, LSRC
4:00 - 5:15

Anthropogenic Nitrogen Mobilization Drivers, Consequences and Opportunities for Action
Dr. James Galloway, Environmental Sciences, University of Virginia

Food and energy production converts N2 to reactive N species that cascade through environmental reservoirs and in the process impact human and ecosystem health. This seminar will examine the impact of this increased N mobilization on the global N cycle by contrasting N distribution in the late-19th century with those of the late-20th century. Primary findings are:

•we have a good understanding of the amounts of reactive N created by humans, and the primary points of loss to the environment;

•we have a fair understanding of the degree of distribution, and the resulting impacts on people and ecosystems;

•we have a poor understanding of nitrogen’s rate of accumulation in environmental reservoirs, which is problematic due to the cascading effects of N in the environment, including enhanced rates of atmospheric reactions, fertilization of terrestrial and aquatic ecosystems, loss of ecosystem biodiversity, and increased emission of greenhouse gases;

In addition, we have a good understanding, in general, of what must be done to reduce the amount of Nr created by human action. The challenge is how to minimize reactive N creation while also maximizing food and energy production.

James N. Galloway is Professor of Environmental Sciences at the University of Virginia. Dr. Galloway received the B.A. degree in Chemistry and Biology from Whittier College in 1966 and the Ph.D. degree in Chemistry from the University of California, San Diego in 1972. Following a postdoctoral appointment with Gene Likens at Cornell University, he accepted a position as Assistant Professor of Environmental Sciences at the University of Virginia in 1976. He served as President of the Bermuda Biological Station for Research from 1988 to 1995, and as chair of Environmental Sciences, University of Virginia from 1996 to 2001. He is currently chair of the International Nitrogen Initiative, a program sponsored by SCOPE and IGBP, and is a member of the EPA Science Advisory Board. In 2002 he was elected a Fellow of the American Association for the Advancement of Science. His research on biogeochemistry includes the natural and anthropogenic controls on chemical cycles at the watershed, regional and global scales. His current research focuses on beneficial and detrimental effects of reactive nitrogen as it cascades between the atmosphere, terrestrial ecosystems and freshwater and marine ecosystems.

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Wednesday, April 22
A158, LSRC
12:00-1:15pm

Regime Shifts in the Northern Rockies: A key to understanding climate-fire-human interactions
Lisa Graumlich, Big Sky Institute for Science and Natural History, Montana State University

In the past decade, atmospheric scientists uncovered evidence for a fundamental climatic regime shift in the winter of 1976-1977 driven by changes in sea surface temperatures in the Pacific Ocean. Ecologists in the Pacific Northwest have documented synchronous and substantial ecosystem responses to the 1977 event. Accumulating evidence from long-term climate records suggests that such regime shifts are the norm. For regions such as the Northern Rockies this regime-like behavior results in extended (>10 yr) periods of drought alternating with more mesic conditions. In this paper, I describe efforts by my lab group to define the nature and causes of climate regime shifts in the Northern Rockies and to define the consequences of these regime shifts for ecosystem processes, especially disturbance processes such as fire. Wildfire in the 20th century turns out to be a particularly intriguing topic because of the potential for feedbacks between regime shifts in climate and similarly abrupt shifts in fire management policies and practices.

Dr. Lisa J. Graumlich’s position as Executive Director of the Big Sky Institute for Science and Natural History at Montana State University allows her to combine her career-long interest in mountain regions and natural areas with her concerns for sustainability. As a researcher, she uses tree-ring records to investigate how climate variation affects forests and disturbance processes such as wildfire.. Dr. Graumlich is also active in developing program and institutions that address critical questions of global environmental change. In 19993, she was chosen as the first Director of the University of Arizona’s Institute for the Study of Planet Earth (ISPE). While Director of ISPE, she developed an integrated program of research, education, and outreach focusing on the impacts of climatic variability on semi-arid regions. In 1999, she moved to Montana State University to direct the Mountain Research Center (MRC). In 2001, she was selected as the Executive Director of MSU’s Big Sky Institute (BSI). Her goal for BSI is to develop an integrated program linking science, education and decision making in the Greater Yellowstone Ecosystem and other similarly large and complex ecosystems.

Dr. Graumlich received her Ph.D. from the University of Washington (1985). She was named an Aldo Leopold Leadership Fellow in 1999 and was elected as Fellow of the American Association for the Advancement of Science in 2004.

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Monday, April 26
A148, LSRC
10:00–11:15am

Rolling Easements and Other Free-Market Solutions to Sea Level Rise
Jim Titus, Global Change Information Branch, U.S. Environmental Protection Agency

For the last several thousand years, sea level has risen so slowly that for most practical purposes, it has been constant. And so people have developed our coast as if water levels do not rise, as if shores do not erode. But they do.

Some homes that were once a safe distance back from the shore now stand between the dunes and the ocean, in the public right of way. Should that right of way be maintained by removing the structures, or should we let Nature take the blame when the homes are inevitably lost to the sea during the next major storm as the shore migrates inland? Or should we give up these public beaches if the buildings are more valuable, by constructing stone revetments and seawalls? Or shall we keep both the homes and the beaches through sand replenishment? People have different opinions on the best approach—but few would dispute that all of the options for dealing with erosion along the Atlantic Ocean are widely discussed and considered by high-level decision makers. Because North Carolina and the coastal counties value their ocean beaches, the primary policy question is how much public money do we invest on sand replenishment to protect private property that must otherwise be removed.

Along the sounds, rising seas and eroding shores confront us with the same three choices. But the costs and benefits associated with each of the options seem to be leading us in a different direction. Waves are smaller along the sounds, which makes the cost of shoreline armoring small compared with the value of property being protected. Therefore, except in cases of extreme subsidence, homeowners have no economic reason to retreat along sounds. The armoring eliminates the intertidal zone, but because recreation and transportation along bay shores is minimal compared with the ocean, the public tolerates the elimination of soundside beaches.

Although most people are content to see the intertidal shores replaced with shore protection structures, horseshoe crabs, sea turtles, terrapins, king fisher, and numerous other shorebirds require estuarine beaches for feeding and breeding. Mudflats and tidal wetlands are directly or indirectly important to most aquatic species. If only a portion of the shore is armored, these species can go elsewhere; but the loss of most natural shores would be problematic.

In the 1970s, Congress and the States did something that in retrospect, seems truly amazing: they placed most of our tidal wetlands and beaches off limits to development. The coastal dry lands are being developed, but as long as the sea does not rise and the shores do not erode, tens of thousands of square miles of rich habitat are protected—as well as tens of thousands of linear miles of tidal shores. Over the next decade or so, these ecosystems seem safe. But as one looks farther into the future, it seems increasingly likely that the sea will rise enough of eliminate existing tidal wetlands and beaches.

Humanity is changing the atmosphere and gradually warming the climate through a mechanism commonly known as the “greenhouse effect.” In the last century, the Earth’s average surface temperature has risen about 1 degree Fahrenheit. The warmer temperatures have raised sea level 3-4 inches by expanding ocean water and melting small mountain glaciers. Tide gauges show that the sea has risen about one foot relative to the North Carolina Coast, with about 6 inches attributable to subsidence. There is a general consensus that average worldwide sea level has risen 4-8 inches in the last century—various theories have been offered for the discrepancy between the observed rise and what we are able to explain.

Many scientists expect sea level rise to accelerate over the next several decades. Rising temperatures will continue to melt mountain glaciers and expand ocean water, and the portion of Greenland where temperatures are warm enough to melt ice will may gradually increase. A Monte Carlo analysis by EPA suggested a median estimate in which the sea rises 10 inches more in the next century than in the last century, with a 1% chance of an extra 3 feet. That analysis and similar projections by the United Nations Intergovernmental Panel on Climate Change calculate that sea level rise has been accelerating over the last fifty years. Yet the data shows no such acceleration. The data does show that the sea has been rising more rapidly in the last century than during the last several thousand years. Some scientists who prefer data over theory have concluded that the current rate of sea level rise probably includes whatever acceleration from greenhouse gases we might expect to see over the next few decades. No one is seriously projecting a deceleration of sea level rise, except for areas like Bangkok and parts of Texas where withdrawals of groundwater and other fluids have been curtailed.

EPA has long recommended that coastal planners and managers prepare for the consequences of sea level rise, not because an impending catastrophe awaits us, but because there are many cost effective opportunities to prepare now—opportunities that might be lost if we wait. The most important thing to do now is start deciding which areas will be protected with dikes, which areas will be elevated, and which areas will retreat. The cost of elevating a community can be modest if fill is simply brought in as roads are rebuilt, or yards are re-landscaped. But city engineers and property owners need a signal that this is the plan—why bother if the community will be encircled by a dike instead? Preserving coastal ecosystems may require the longest lead time of all. EPA and North Carolina Seagrant have been working with local authorities to develop maps depicting the areas that will be protected from rising sea level.

North Carolina was one of the first states to adopt erosion-based setbacks along the ocean. For some states, those setbacks were a way of delaying the day of reckoning for 30-60 years; but in North Carolina, there tended to be an implicit assumption that homes will eventually be lost or relocated. The setback simply ensured that erosion did not prevent the owner from enjoying a reasonable lifetime for the structures (e.g. duration of the 30-year mortgage). These setbacks do not apply along sounds, but even if they did, the day of reckoning there generally means building a shore protection structure.

Texas has made an important contribution to the nation’s tools for saving wetlands and beaches as sea level rises: the rolling easement. Elsewhere, this author demonstrates that in a free market economy with rational buyers and sellers, the rolling easement is an order of magnitude more economically efficient than a coastal setback. Although the rolling easement in Texas refers to a public right under the common law, people are also starting to think of it as a type of conservation. The primary benefits are that the riparian owner gets compensated, and the “moral hazard” risk that the terms of the agreement will not be enforced is less, because conservancies and conservation agencies would own the easements. Rolling easements are an efficient instrument for allocating the risk of sea level rise, because the environmentalist purchaser perceives the risk of sea level rise to be greater than the typical coastal property owner, and weighs the long-term more as well (i.e. discounts future returns at a lower discount rate).

In North Carolina, the Nature Conservancy is starting to think about long-term planning for ensuring that wetlands survive rising sea level. The rolling easement is one possible tool. Even if policy makers prefer to avoid interfering with the gradual elimination of wetlands as sea level rises, private conservancies can do a lot to ensure that wetlands can migrate inland.
click for map

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FALL 2003

Wednesday, October 1
A150 LSRC, 4:00pm

Analysing observed changes in climate extremes
Lisa Alexander

Since the Intergovenmental Panel on Climate Change (IPCC) Second Assessment Report concluded that there was not enough evidence to adequately assess changes in observed climate extremes, a concerted international effort was established to fill in these gaps. For many reasons, however, a lot of countries are more inclined to release derived data in the form of annual indicator time series than to release their original daily observations. For the IPCC Third Assessment Report in 2001, this led to the production of a global dataset of derived indicators based on temperature and precipitation to clarify whether the frequency and/or severity of climatic extremes changed during the second half of the 20th century. Coherent spatial patterns of statistically significant changes emerge, particularly an increase in warm summer nights and a decrease in frost days and intra-annual temperature range. Indicators based on daily precipitation data show more mixed patterns of change but a significant increase has been seen in the number of heavy rainfall events with a significant decreasing trend in the number of consecutive dry days. However, large areas of the globe are still not represented, especially Africa and South America and the international effort continues to gain more information in these regions.

Lisa Alexander received a BSc(Hons)in Applied Mathematics, Queens University, Belfast, N. Ireland, and an MSc in Computational Science, Queens University, Belfast. Since 1998 she has worked for the Hadley Centre for Climate Prediction and Research as a climate research scientist. Her main area of research is analysing changes in the observed climate, both regional and global, with a particular emphasis on climate extremes.

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Wednesday, October 8
A158 LSRC, 4:00pm

Assessing Uncertainty in Mesoscale Numerical Weather Prediction
Montserrat Fuentes

Current methods of meteorological forecasting produce predictions with unknown levels of uncertainty, particularly in regions with few observational assets. Forecast errors and uncertainties also arise from short-comings in model physics. With the ability to estimate the uncertainty in predictions, forecasters would have a powerful tool to make decisions. The goals of our work are to develop methods for evaluating the uncertainty of mesoscale meteorological model predictions, and to create methods for the integration and visualization of multisource information derived from model output, observations and expert knowledge. We do this by extending the recently developed Bayesian melding approach. We also will develop a new approach to assess the performance of mesoscale numerical models, and show how it can also be used to remove the bias in model output. We specify a simple model for both numerical model predictions and observations in terms of the unobserved ground truth, and estimate it in a Bayesian way. We applied these statistical methods to weather mesoscale models (MM5) and to air quality numerical models (Models-3).

Montserrat Fuentes is an associate professor in the Statistics Department at North Carolina State (Ph.D. from the University of Chicago in 1998). Dr. Fuentes also has an associate status in the Marine Earth Atmospheric Sciences Department at NCSU. She spent 6 months as a postdoc in the National Center of Atmospheric Research (NCAR) before joining NC State. She has worked on spatial-temporal statistics and applications to atmospheric pollution and meteorology, and in 2003, received the Abdel El-Shaarawi Young Research's Award in recognition of outstanding contributions to environmetric research. She is currently a member of the model evaluation team at EPA. Dr. Fuentes has developed new statistical methods applied to weather forecasting and air pollution, and has collaborated with the air quality modelers and scientists at EPA and NCAR, monitoring network design, spatial interpolation of environmental processes, evaluation of air quality and weather numerical models, assessment of uncertainty in air quality prediction, data assimilation, ensemble forecast and the statistical assessment of geographic areas of compliance with air quality standards.

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Wednesday, October 15
A158 LSRC, 4:00pm

The Conquest of North American Forests by Alien Insects and Pathogens: Case History of the Population Biology and Management of Gypsy Moth Spread
Andrew “Sandy” Liebhold

Alien insects and diseases are having devastating ecological effects on North American forests. This problem is well illustrated by the gypsy moth, Lymantria dispar, which was accidentally introduced from Europe to N. America in 1869 by an amateur naturalist. Since that time, the range of this insect has gradually expanded and outbreaks of this insect have damaged millions of ha of forest. The gypsy moth’s radial rate of range expansion over the last 40 years has averaged about 20 km/yr. Comparison of predictions from a simple reaction-diffusion model with historical spread rates indicate that accidental movement of life stages (by humans) has greatly accelerated the spread of the species.

As has been found in several other alien species, spread occurs by a type of “stratified dispersal” in which isolated colonies are founded ahead of the advancing front; these colonies gradually enlarge and eventually coalesce with the rest of the insect’s range. This phenomenon has been captured in a model that we have used to develop optimal strategies for retarding the spread of this species. Implementation of this strategy is currently underway; results to date indicate that range expansion can be reduced by ca. 50%. The gypsy moth’s range still has not reached over 2/3 of its potential range in North America but life stages are often accidentally introduced to new areas well beyond the expanding population front. Sometimes these introductions establish isolated colonies and eradication is attempted once they are detected.

Analysis of historical data on isolated colonies indicates the dominance of Allee effects and stochasticity in the dynamics of low-density, isolated populations. This information was used to parameterize a model that can be used to evaluate eradication strategies. These results can be generalized and applied to the development of strategies for managing invasions of other types of alien organisms.

Sandy Liebhold is a Research Entomologist with the Northeastern Research Station of the USDA Forest Service located in Morgantown, WV (Ph.D. from University of California, Berkeley 1984). Dr. Liebhold also is adjunct faculty with Penn State and West Virginia Universities. His research revolves around various aspects of forest insect population ecology but most of his work focuses on two areas: 1) the spatial dynamics of forest insect outbreaks and 2) the population biology of forest insect invasions.

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Wednesday, October 29
A158 LSRC, 4:00pm

Fire and the global carbon cycle
James T. Randerson

During the 1997–98 El Niño, the terrestrial biosphere experienced drought conditions that triggered widespread increases in fire activity. Here I present a study that combined satellite-based estimates of burned area and an inverse analysis of atmospheric CO anomalies to evaluate the contribution of fire emissions from different continents to trace gas variability during this period. We found that Southeast Asia accounted for ~60% of the global fire emissions anomaly during the El Niño, and that significant and previously underestimated contributions from Central America (20%), northern boreal regions (10%), and South America (south of the equator; 10%) were also critically important in terms of explaining atmospheric trace gas anomalies. Globally, total carbon emissions from fires were 2 Pg C/yr higher in 1998 than in 2000, and accounted for ~2/3 of the CO₂ growth rate anomalies during the study period.

Dr. Randerson is a biogeochemist interested in global carbon and nutrient cycles. He uses atmospheric trace gas observations, satellite data, and models to study the biosphere. He is currently investigating pathways of rapid carbon loss from terrestrial ecosystems including fire emissions and permafrost degradation. His group works at field sites in Alaska and Siberia. Dr. Randerson is currently an Assistant Professor at UC Irvine, Department of Earth System Science; he received a Ph.D. in Biological Sciences from Stanford University (1998) and a BS in Chemistry from Stanford (1992).

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Wednesday, November 5
A-158 LSRC 4:00pm

Ecological Forecasting, Coupling Ecosystem Hydrodynamics and Carbon Transport, and Ocean Climate Modeling: Updates from the First Three CGC Working Groups

The Center on Global Change (CGC) funds new and innovative faculty/post-doc/graduate student collaborations across disciplines in the area of global change. These working groups typically involve both research and graduate teaching. The principal investigators of each of the first three CGC working groups will discuss their group's activities:

Ecological Forecasting (Jim Clark, Dean Urban, Pankaj Agarwal, Michael Lavine)
Presented by Mike Dietze (Ecology) and Satish Govindarajan (Computer Sciences)

The ability to anticipate ecological change in regions of rapid development is one of the greatest challenges to environmental scientists. Mike and Satish will provide an overview of a forest simulator being developed to model population and ecosystem responses to environmental change.

Coupling Ecosystem Hydrodynamics and Carbon Transport (John Albertson, Gaby Katul, Ram Oren, Andrea Bertozzi)
Presented by John Albertson (Civil and Environmental Engineering)

Terrestrial systems play an important role in regulating atmospheric CO₂ and water cycling. However, there are large uncertainties in estimates of present terrestrial carbon uptake, and even larger uncertainties in predicting the dynamic response of net ecosystem carbon exchange to future climate. Collaborative efforts to develop predictive numerical models of the coupled water and carbon transport within ecosystems at multiple spatial and temporal scales will be described.

Ocean Climate Modeling (Susan Lozier, Dick Barber, Gabi Hegerl, Yi Chao, Fei Chai, Mark Reed)
Presented by Susan Lozier (Earth and Ocean Sciences)

The oceans play a major role in determining global climate, both as a reservoir of carbon and heat, and through the distribution of heat, freshwater, and carbon. However, there is limited understanding of the complex oceanic lag times and linkages between radiative input and ocean response. The results of the work of physical and biological oceanographers, a climatologist, ocean modeler, and computational scientist to understand how ocean biology and physics respond to a climate perturbation, and the extent to which this response is fed back to the climate system, will be described.

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Wednesday, November 12
A158 LSRC, 4:00–5:15pm

Transgenic pines at the interface of private and public lands:
A case study in landscape genomics
Claire G. Williams

Landscape genomics pertains to the use of DNA sequence data or other types of genomics analysis to make inferences about past, present or future ecosystem changes. Some of my landscape genomics research areas include 1) deducing the response of a species to Holocene climate change, 2) using DNA from ancient wood to infer early human impact on maritime forests, and 3) exploring timber origin in nautical archaeology.

A present-day application of landscape genomics explores the risk of transgenic forest tree invasiveness at the interface of private and public lands. Modeling transgenic P. taeda as an invasive colonizer shows that its seeds and pollen alike travel long distances at meso-transport levels and that subsequent colonization will be substantial. The consequences of colonization can be modeled using net fitness models to predict transgene spread. Risks associated with transgenic pine escape and colonization include species displacement or ecosystem disruption as well as human health because pine pulping byproducts are used as food additives, soaps, cleaners and industrial lubricants. Risk analysis has raised interesting questions about options for transgenic pine biosafety. Options range from a complete moratorium on transgenic plantings to reproductive sterility research, to mandates for early transgenic testing removal or alternative biocontainment zone designs. These options must be considered not only in light of potential benefits but also climate change projections which suggest that many southern US pine species—transgenic or otherwise—will become more invasive given elevated CO₂ levels.

Claire Williams is a professor in genetics and forestry at Texas A&M University; her seminar presentation is based on collaborations with the Center on Global Change, the Nicholas School and the Forest History Society at Duke University as well as the University of British Columbia’s Faculty of Forestry in Canada.

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SPRING 2003

Thursday, January 30
A158 LSRC, 4:00pm

Life in Marine Sediments: Probing the Limits of Earth’s Deep Biosphere
David C. Smith, University of Rhode Island

The presence of an active microbial community inhabiting deeply buried marine sediments has previously been inferred from profiles of chemical compounds involved in microbial metabolism (e.g., sulfate and methane). Studies on recent ODP Legs to quantify microbial abundance in cores have confirmed their presence down to at least 800 m below the sea floor. Extrapolation of these results suggests that the cumulative biomass in subsurface marine sediments comprises a significant portion of the total biomass on Earth. Recently, the capabilities of the JOIDES Resolution have been expanded so that microbiological experiments can now be conducted onboard. This allows microbiologists to better understand what controls microbial distribution and activity and consequently their biogeochemical impact in the marine subsurface. Approaches include measuring rates of metabolic reactions, cultivating microbes recovered from the cores, and characterizing the microbial community through nucleic acid analysis. These efforts will provide insights into the adaptations of microorganism to this environment and will help us define the limits of the deep biosphere on Earth.

Dr. David Smith is an assistant professor of oceanography at the University of Rhode Island. His areas of specialization and current research include marine ecology with an emphasis on food web dynamics as related to marine biogeochemistry. Dr. Smith received his Ph.D. in marine biology from Scripps Institute of Oceanography, University of California, San Diego in 1994. Dr. Smith has sailed as a microbiologist on ODP Legs 185, 190 and 201. (Host: Paul Baker, EOS)

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Thursday, March 27
A150 LSRC, 12:00pm

The Atlantic thermohaline circulation and its role in climate variability and change
Tom Delworth, Geophysical Fluids Dynamics Laboratory, NOAA

An overview is presented of the role of the Atlantic thermohaline circulation (THC) in climate variability and change, and the factors which can influence the THC. The THC has a potentially important effect on Atlantic climate through its meridional transport of heat and freshwater. On decadal to centennial time scales, fluctuations in these transports can have a substantial impact on Atlantic sea surface temperatures, as well as possible impacts on the climate of adjacent continental regions. Modeling studies suggest that observed SST multidecadal variations in the 20th century may have been caused by THC fluctuations. The THC changes can affect the meridional position of the Intertropical Convergence Zone, thereby potentially altering tropical convection and large-scale atmospheric circulation.

Thomas L. Delworth has worked at the NOAA Geophysical Fluid Dynamics Laboratory in Princeton, New Jersey since 1984. He is a member of the Climate Dynamics and Prediction Group. He received his Ph.D. from the University of Wisconsin in 1993. As a graduate student, he wrote his thesis on soil wetness and climate variability. Primarily, his research interests have focused on decadal to centennial climate variability and change. He has examined the role of the ocean in the climate system, with special emphasis on the Atlantic and Arctic regions. He has also examined hyrdologic variability and change over continental regions. (Host: Gabi Hegerl, EOS)

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Thursday, April 3 CANCELLED
A158 LSRC, 4:00pm

The optimal stability window and marine ecosystem variability in the strait of Georgia, British Columbia
Ann Gargett, Old Dominion University

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Thursday, April 10
A158 LSRC, 4:00pm

Advanced technology paths to global climate stability: energy for a greenhouse planet
Marty Hoffert, New York University

Stabilizing climate is an energy problem. To set ourselves on a course towards climate stabilization will require a build-up within the coming decades of new primary energy sources that do not emit carbon dioxide to the atmosphere, in addition to efforts to reduce end-use energy demand. Mid-century CO₂ emissions-free primary power requirements could be several times what we now derive from fossil fuels (~1013 W), even with improvements in energy efficiency. Here we survey possible future energy sources, evaluated for both their capability to supply the massive amounts of CO₂ emissions-free energy required and their potential for large-scale commercialization. Possible candidates for primary energy sources include terrestrial solar, wind, solar power satellites, biomass, nuclear fission, nuclear fusion, fission-fusion hybrids and fossil fuels from which carbon has been sequestered. Non-primary power technologies that could contribute to climate stabilization include: conservation, efficiency improvements, hydrogen production, storage and transport, superconducting global electric grids and geo-engineering.

Marty Hoffert is professor of physics and former chair of the department of applied science at New York University. His research includes energy science & technologies, global climate change, oceanography, biogeochemical cycles, fluids and plasmas and wireless power transmission. His recent work focuses on technology paths for transitioning away from fossil fuels whose CO₂ emissions are freely vented to the atmosphere to energy futures in which humankind's power derives from radically different primary sources. Major collaborative multi-disciplinary studies in which he is the lead author include Advanced Technology Paths to Global Climate Stability: Energy for a Greenhouse Planet, published in the Nov. 1, 2002 issue of Science, and Energy Implications of Future Stabilization of Atmospheric CO₂ Content, which appeared in the October 29, 1998 issue of Nature. (Host: Tom Crowley, EOS)

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Wednesday, April 16 (Informal Seminar)
CGC, 11:00am

The NAO and the Gulf Stream: Basin scale interactions to regional scale variability
Avijit Gangopadhyay, University of Massachusetts Dartmouth

The low-frequency impact of the North Atlantic Oscillation (NAO) on the Gulf Stream system is discussed from a multiscale perspective. Specifically, the impact of the NAO on the Gulf Stream system is described in terms of two basin-scale gyre-specific dynamic responses: (i) the wind-driven response associated with the subtropical gyre centered on the Azores High, and (ii) the thermohaline response associated with the subpolar gyre centered on the Icelandic Low. Both temporal and spatial coverage of NAO effects are considered.

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Thursday, April 17
A158 LSRC, 4:00pm

Climate Variations and Change: What can we say with confidence?
Thomas R. Karl, National Climatic Data Center, NOAA

Documenting climate change and variability is a formidable task made difficult due to a variety of observing characteristics that affect our observing systems both today and in the past. A review of data from the ice ages to the space age, reveals considerable information as well as substantial uncertainties. These data will be explored to show what we know with confidence and what remains uncertain and why. Opportunities for better climate information will also be identified.

Dr. Karl is a fellow of the American Meteorological Society and the American Geophysical Union, and a national associate of the National Research Council. In 2002 he was elected to serve on the Council of the American Meteorological Society. In addition to Dr. Karl’s participation on various committees, he has also testified to the U.S. Congress and briefed cabinet level officials, the Vice President, and the President of the United States. Dr. Karl is author of many climatic atlases and technical reports and has well over 100 published articles. In addition to his contributions to numerous journals, Dr. Karl has also served as editor or contributor to eleven commercial textbooks on topics ranging from the 1988 U.S. drought to global climate observing. (Host: Tom Crowley, EOS)

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Wednesday, April 23 (Informal Seminar)
CGC, 11:00am

Ocean Modeling: Linking physical and biological processes
Ping-Tung Shaw, NCSU

Upwelling of subsurface water in the South China Sea and sinking of dense water plumes in the Arctic continental margin, two processes of potential contribution to global change, are discussed. The South China Sea is adjacent to the warm pool of the western Pacific. Weakened upwelling in the South China Sea during El Niño is known to result in warming of the surface water. The effects of variation in circulation on biogeochemical processes are studied in a numerical model with added biogeochemical components at 0.4° resolution. The model reproduces main features of seasonal variation in chlorophyll patterns in regions of strong upwelling. However, discrepancies in the dispersion of high chlorophyll patches are found. Insufficient data to properly constrain boundary conditions for dissolved inorganic nitrogen and the inadequate model resolution are likely the source of errors.

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Wednesday, April 23 (Informal Seminar)
A247 LSRC, 4:00pm

The Art and Role of Climate Modelling
Hans von Storch, German Hydrological Institute

In this talk, the art of quasi realistic climate modeling is reviewed. Its limitations—such as the failure to immediately constitute knowledge (insight into climate dynamics) or to provide regional detail, or the impossibility for positive verification—are discussed. The talk is concluded with a short discourse about the contemporary public role of climate models.

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Thursday, May 1
203 Teer, 3:00pm

{note: time and location change}

Aerosols and Climate
John Seinfeld, California Institute of Technology

The role of aerosols is now recognized to be perhaps the major uncertainty in the understanding of how the Earth's climate will evolve in the next decades. Aerosols produce competing climatic effects, both cooling and warming, and interact with clouds in complex ways. We will review what is known and quantifiable about the effect of aerosols on climate and discuss where future challenges lie.

John H. Seinfeld is the Louis E. Nohl Professor in the Divisions of Chemistry and Chemical Engineering and Engineering and Applied Science at the California Institute of Technology. He is currently vice chair of the NRC Committee on Atmospheric Chemistry. He received his Ph.D. in chemical engineering from Princeton University in 1967. Dr. Seinfeld is the author of more than 400 scientific papers and several books, including Atmospheric Chemistry and Physics: From Air Pollution to Climate Change (1998). (Host: Prasad Kasibhatla, ESP)

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Thursday, May 1
104 Old Chemistry, 11:00am

Remote Influences on South Americal Climate Variability
Andrew W. Robertson
International Research Institute for Climate Prediction (IRI), The Earth Institute at Columbia University

The climate of South America is strongly influenced by the surrounding oceans on many time scales, ranging from the intraseasonal to the interdecadal. I will focus on subtropical South America, east of the Andes, where the South Atlantic Convergence Zone is a major organizing circulation feature. I will use NCEP/NCAR reanalysis data to discuss the remote influences of ENSO, and GCM experiments to investigate the role of Atlantic SST anomalies. Some evidence of NAO & PDO influence on longer time scales will also be presented, using a century of Plata basin river records.

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FALL 2002

Thursday, September 5
Center on Global Change, 4:00pm

Measuring land-atmosphere exchange in complex terrain
John Finnigan, CSIRO

Aerodynamic methods of measuring land-atmosphere exchange rely on using the mixing inherent in the turbulent atmosphere as an averaging operator, thereby avoiding the crippling sampling problem that occurs if average surface exchange is estimated by adding many measurements from soil chambers or leaf cuvettes. It has a venerable history but recent long-term continuous measurements from flux towers in the world-wide FLUXNET program have called into question many basic assumptions embodied in its practical application.

Dr. John Finnigan is with CSIRO (Australia) Atmospheric Research and serves as interim director of the CSIRO Centre for Complex Systems Science. (Host: Gabi Katul, ESP)

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Thursday, October 17
A247 LSRC, 4:00pm

Tropospheric ozone as a climate gas and air pollutant: the case for controlling methane
Daniel J. Jacob, Harvard University

Human activity has caused a global-scale increase in tropospheric ozone
over the past century, with important implications for both climate change
and surface air quality. Dr. Jacob will briefly review the current state of
understanding of the global budget of tropospheric ozone and show that the radiative forcing of climate by ozone is more uncertain (and potentially much larger) than is usually assumed—and that radiative forcing is a rather poor index for quantifying the perturbation to climate by ozone. Thus ozone is less efficient at warming the surface, and more efficient at cooling the stratosphere, than the same radiative forcing increment of carbon dioxide. He will examine possible strategies to decrease the climate forcing from ozone in the future and show that emission controls on methane would provide an efficient vehicle with benefits for both climate change mitigation and air quality. A discussion of ongoing work at Harvard to improve understanding of regional methane emissions through top-down model analyses will conclude the seminar.

Dr. Jacob is Gordon McKay Professor of Atmospheric Chemistry and Environmental Engineering at Harvard University. He received his Ph.D. in environmental engineering in 1985 from the California Institute of Technology. He does research in the chemical composition of the atmosphere and its perturbation by human activity with work on global three dimensional modeling of atmospheric chemistry and climate change, aircraft measurement campaigns, satellite data retrievals and analyses of atmospheric observations. (Host: Prasad Kasibhatla, ESP)

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Friday, October 25
201 Old Chemistry, 4:00pm

Responses of coastal wetlands to rising sea level
James T. Morris, University of South Carolina (co-sponsored with EOS)

Sea level rise is likely to accelerate as a consequence of global warming. Long-term measurements at North Inlet, SC show that a recent acceleration in the rate of sea-level rise has led to increases in marsh productivity, averaging 32 g m-2 yr-1, and biogeochemical cycling. Spartina alterniflora, the dominant macrophyte in east coast salt marshes, maintains the elevation of its habitat within a narrow portion of the intertidal zone by accumulating organic matter and trapping inorganic sediment. The long-term stability of these ecosystems is explained by interactions among MSL, land elevation, primary production, and sediment accretion. This equilibrium is adjusted upward by increased production of S. alterniflora and downward by an increasing rate of relative sea-level rise (RSLR). Adjustments in marsh surface elevation are slow in comparison to interannual anomalies and long-period (decadal) cycles of sea level, and this lag in the marsh response results in significant variation in annual primary productivity. A theoretical model predicts that the system will be stable against changes in relative mean sea level when surface elevation is greater than that which is optimal for primary production. When surface elevation is less than optimal, the system will be unstable. The model predicts that there is an optimal rate of RSLR at which the equilibrium elevation and depth of tidal flooding will be optimal for plant growth. However, the optimal rate of RSLR also approaches an upper limit. Beyond this limit, the plant community cannot sustain an elevation that is within its range of tolerance. Moreover, the range of tolerance is proportional to tidal amplitude. For mesotidal estuaries with high sediment loading, such as those on the U.S. southeast coast, the limiting rate of RSLR was predicted to be at most 1.2 cm/yr, which is 3.5 times greater than the current, long-term rate of RSLR.

Dr. James T. Morris is a professor of biological and marine sciences at the University of South Carolina. He received his Ph.D. in 1979 from Yale University. His research spans the basic and applied aspects of the physiological ecology of plants adapted to wetland habitats and the biogeochemistry and systems ecology of wetlands, primarily salt and freshwater intertidal wetlands. (Host: Brad Murray, EOS)

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Wednesday, October 30
A156 LSRC, 12:30pm

The prospects for a fragmented climate regime
Henry D. Jacoby, MIT (co-sponsored with the Center for Environmental Solutions)

The first attempt at a common global climate regime is ending in fragmentation. It seems likely (though far from certain) that within the next few years Russia will ratify the Kyoto Protocol, completing the requirements for entry into force. It is similarly unlikely that the US will accept the existing Kyoto structure, which would require abandoning its growth-indexed approach to emissions targets and its insistence on developing country participation. Other developed nations may follow the US lead or take still other approaches. Yet any effective response to the global climate threat ultimately will require some degree of global collaboration. In the opening talk, results from the MIT Environmental Prediction and Policy Analysis (EPPA) model will be used to predict likely achievements under the Kyoto and Bush programs, and to explore possible avenues for future negotiations. It will raise questions for subsequent discussion, including the limits to a Kyoto-style approach to a global regime, possible gains from a looser structure, and puzzles regarding the venue within which a coherent approach might be sought.

An economist with a background in engineering, Henry (Jake) Jacoby is a professor of management in the MIT Sloan School of Management and co-director of the MIT Joint Program on the Science and Policy of Global Change. He has been director of the Harvard Environmental Systems Program, director of the MIT Center for Energy and Environmental Policy Research, associate director of the MIT Energy Laboratory and chair of the MIT faculty. His career interest is in issues of economics and policy in the areas of energy, natural resources and environment. The MIT Joint Program on the Science and Policy of Global Change brings together a group of natural and social scientists and policy analysts for joint work focused mainly on the threat of global climate change and the assessment of efforts to mitigate human interference with the climate system. (Host: Jonathan Wiener, CES)

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Wednesday, November 13 (Informal Seminar)

Interpreting Woody Plant Richness from Seasonal Ratios of Photosynthesis across Oregon
Richard Waring, Distinguished Professor Emeritus, Forest Science Department, Oregon State University

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Thursday, November 14
A247 LSRC, 4:00pm

Genomic response to ecological change: finding the lost pines
Claire G. Williams, Texas A&M University

DNA signatures carry a record of past population dynamics and thus can be used to reconstruct a plant's response to radical shift in climate change after glaciation. In this study, DNA signatures were interpreted within a framework of geological and historical records, population genetics theory and geographic information systems (GIS), Using a wealth of geological, historical, climatic data, we constructed specific hypotheses about
population response to radical climate change events in central Texas over the past 10,000 years. The Lost Pines, a set of scattered pine islands islands in central Texas, is disjunct from the larger range of Pinus taeda L. in the southern quadrant of North America. Study objectives were 1) to test for bottleneck events in the Lost Pines, 2) to test if this population is indeed the species' post-Pleistocene retreating edge and 3) to test whether its contemporary distribution patterns are constrained by edaphic patterns. Constructing and testing these hypotheses has been an ongoing collaborative effort with archaeologists, ecologists, GIS experts and geologists.

Dr. Williams is a professor in genetics and forestry at Texas A&M University. A 2002 recipient of a Guggenheim Fellowship, she is on sabbatical at the Center on Global Change this autumn while she completes a book on the evolution and ecology of conifers for Cambridge University Press. (Host: Barbarb Braatz, CGC)

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SPRING 2002

{All seminars are presented in A247 LSRC unless otherwise noted}

Thursday, January 17

A study of the response of ocean biology to future climate change
Jorge Sarmiento, Princeton University

Climate models predict that global warming will cause major increases in
oceanic stratification that are likely to have a large impact on marine
biology. Six different coupled climate model simulations of future climate
change are examined to determine the range of behavior of those physical
properties of global warming simulations that are likely to be most relevant
to the ocean biological response. Satellite color and ocean climatological
observations are used to develop an empirical model for predicting
chlorophyll from the physical properties predicted by the global warming
simulations. Application of this empirical model to the global warming
simulations suggests that the oligotrophic (tow productivity) gyres of the
oceans will expand and experience reduced biological production. High
latitude regions that are presently characterized by deep winter mixing will
tend to experience increased biological production. Our scientific
understanding of this issue is only at the most rudimentary level at present.

Dr. Sarmiento received his Ph.D. from Columbia University in 1978. He
joined the Princeton University faculty in 1980 and was appointed director of
its atmospheric and oceanic sciences program, continuing in that position
until 1990. (Host: Tom Crowley, EOS)

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Thursday, January 24

Understanding Historical and Predicting Future Climate Change
Simon Tett, Hadley Centre

The twentieth century has shown two periods of climate change: from about 1910 to 1940 and from the mid 1970s to present. What might be the causes of these changes? As we only have one Earth we cannot easily carry out controlled experiments to explore the reasons for these changes. Using climate models allows investigation of the possible causes of these changes.
The physical principals by which these models work will be described. How they have been used to understand 20th century climate change will be alsobe described. These same models can be used to predict possible future climate change. Results from those simulations will be shown.

Dr. Simon Tett is a senior scientist at the Hadley Centre, which he joined in January 1991. He has carried out research into simulated climate variability, climate change, and detection and attribution of observed climate change using three generations of Hadley Centre coupled models. (Host: Tom Crowley, EOS)

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Thursday, February 21

Cycles and epidemic waves in measles dynamics
Ottar Bjornstad, Penn State University

For predator-prey and parasite-host systems, ecological theory suggests that 'traveling waves' are the most striking outcome of spatial-temporal
interactions. To test for the occurrence of this phenomenon. Dr. Bjornstad
investigated measles outbreaks in England and Wales. They showed that
dramatic hierarchical waves of measles Infection move regionally from large cities to small towns. Their model suggests a novel dynamical explanation for the waves. The study firmly demonstrates 'forest fire' dynamics in an endemic epidemiological context.

Dr. Bjornstad is a theoretical ecologist working as an assistant professor in entomology and biology at The Pennsylvania State University. His main
interests are population ecology and population dynamics with particular
emphasis on mathematical and computational aspects. Also an adjunct
assistant professor in statistics, he carries out research in statistical ecology and in methods for analyzing spatiotemporal data. (Hosts: Jim Clark, Biology, and Dan Richter, ESP)

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Thursday, March 21

Nuclear vs. Renewables vs. Decarbonized Fossil Fuels in the Race to Zero Emissions
Robert H. Williams, Princeton University

Radical technological change will be needed to address effectively the
multiple environmental and energy supply security challenges posed by
conventional energy in the 21st century—of which climate change is the
most daunting. Stabilizing the C02 concentration in the atmosphere at 450-550 ppmv might be necessary to prevent major disruptions of climate. So doing would require shifting to energy technologies characterized by near-zero emissions of greenhouse gases. Nuclear energy, renewable energy, and decarbonized fossil energy with C02 sequestration are all candidate options for realizing deep reductions in greenhouse gas emissions. It is helpful to consider electricity generation and "fuels used directly" separately in understanding the competition among these primary energy sources in climate change mitigation.

Dr. Williams is a senior research scientist at Princeton University's Center for Energy and Environmental Studies. His research interests span a wide range of topics relating to advanced energy technologies, energy strategies and energy policy for both industrialized and developing countries. (Host: John Strohbein, Biomedical Engineering)

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Thursday, April 4

Detection of anthropogenic climate change
Gabi Hegerl, Duke University

The atmospheric concentration of carbon dioxide has increased since the industrial revolution and is projected to keep increasing In the future. Global models of the earth's climate system simulate substantial global warming due to this change in the composition of the atmosphere. Since the rate of warming depends on uncertain feedbacks in the climate system it is desireable to estimate what part of the warming in the observed climate record Is anthropogenic and to assess if the model simulations are realistic. The goal is to distinguish the anthropogenic climate change from variability that is inherent in the climate system and from the response to other, natural, mechanisms which Influence the mean state of the earth's climate, such as variations in solar radiation or climate effects of volcanism.

Dr. Hegerl is an associate research professor in the division of earth and ocean sciences at Duke University. Her interests include statistical climatology, climate variability, climatic extremes and climate of the last millennium. (Host: Prasad Kasibhatla, ESP)

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Thursday, April 18

Lightning and Climate: The Water Vapor Connection
Colin Price, Tel Aviv University

The amplitude of future global warming will depend strongly on how upper tropospheric water vapor (UTWV) changes in response to greenhouse gas forcings. There are arguments In support of both positive and negative water vapor feedbacks. To understand these feedbacks it is necessary to understand how UTWV varies on different spatial and temporal scales. However, monitoring long-term changes in water vapor is very difficult, and no single method is in place, or planned, to deal with this problem.

In this paper evidence is presented showing the close link between UTWV variability and global lightning activity. Continental deep convective storms that transport large amounts of water vapor Into the upper troposphere dominate the variability of global UTWV, while also being the storms that produce the majority of our planet's lightning. Furthermore, integrated global lightning activity can be continuously observed from a single location on the earth's surface via the Schumann Resonances (SR), an electromagnetic phenomenon in the atmosphere produced by global lightning. Therefore, observations of the SR may supply a cheap, convenient method of studying the long-term variability of global UTWV.

Dr. Price received his Ph.D. in 1993 from Columbia University where his research dealt with global climate change, having a special focus on global lightning activity. As a postdoctoral student at the Lawrence Livermore National Laboratory, his research dealt with lightning-produced NOx and the implications for tropospheric chemistry. Since 1995 he has been on the faculty of Tel Aviv University in the department of geophysics and planetary sciences. (Host: Steve Cummings, Electrical & Computer Engineering)

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