Designators for special sessions belongs to the lead section or committee abbreviation (i.e., A01 denotes Atmospheric Sciences, P01 denotes Planetary Sciences, etc.).  Additionally, special sessions are listed under all sections or committees who have agreed to sponsor particular sessions.  These sessions are listed after the committee and section primary listing but with the lead section designation.  Some technical committees have elected to only cosponsor sessions.  For example, if you look under Snow, Ice, and Permafrost you will get a listing of all the sessions that this committee has decided to cosponsor.
 

 #Union (U)
 #Atmospheric Science (A)
 #Biogeosciences (B)
 #Geodesy (G)
 #Geomagnetism and Paleomagnetism (GP)
 #Hydrology (H)
 #Ocean Sciences (O)
 #Planetary Sciences (P)
 #Seismology (S)
 #Space Physics and Aeronomy (SA)
 #Solar and Heliospheric Physics (SH)
 #Magnetospheric Physics (SM)
 #Tectonophysics (T)
 #Volcanology, Geochemistry and Petrology (V)
 #Committee on Education and Human Resources (CEHR)
 #Committee on Public Affairs (COPA)
 #Mineral and Rock Physics Committee (MRP)
 #Nonlinear Geophysics (NG)
#Snow, Ice Permafrost (SIP)
 #Study of the Earth’s Deep Interior (SEDI)
 

Union (U)

U01 Paleoenvironmental Evidence for Prehistoric Natural Hazards and Their Impact on Human Societies
Natural hazards have been a significant factor in cultural development in prehistory, including, for example, the hypothesized impact of prolonged droughts on the sustainability of various cultures in the Americas.  In this session we seek examples of paleoenvironmental evidence of droughts, floods, volcanic eruptions, seismicity, etc. and their impact on cultures along the Pole-Equator-Pole I transect (the Americas) and elsewhere.  Clear lines of evidence for paleoenvironmental change either in extreme events in or mean state should be presented independent of the evidence for cultural response.  To the extent possible, the link between environmental change and the potential cultural response should be established.  The objective will be to bring together independent lines of evidence to gauge human response to environmental change both in prehistory and as a guide to the future.
Conveners: Geoffrey Seltzer, Department of Earth Sciences, Syracuse University, 204 Heroy Geology Lab, Syracuse, NY 13244 USA, Tel: +1-315-443-4980, Fax: +1-315-443-3363, E-mail: goseltze@syr.edu  Mark Brenner, Department of Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL 32653 USA, Tel: +1-352-392-9617 ext 232, Fax: +1-352-846-1088, E-mail: brenner@ufl.edu

U02 Bringing Geoscience to Bear on Natural Hazards Risks Worldwide
This session will examine how science is, or could be, used to guide public policy decisions to mitigate natural hazards risks.  The session's emphasis will be on global risks, including those that occur worldwide (such as floods, earthquakes, volcanoes, and hurricanes) and those that are global in nature (such as space weather and climate change). We will focus on international strategies for alleviating risks, with particular attention to mitigation options for developing countries that have relatively small scientific communities and limited resources.  We invite papers from geoscientists, social scientists and policy professionals who have worked on either the relevant scientific research or its application to natural hazards policy. AGU members from developing countries are particularly encouraged to submit abstracts addressing the kinds of scientific research and cooperation they see as most important in helping to make progress against natural hazard destruction.
Convener: Margaret R. Goud Collins, Program Director, U.S. Committee for IIASA, American Academy of Arts and Sciences, Norton's Woods, 136 Irving St., Cambridge, MA  02138 USA,
Tel: +1-617-576-5019 or +1-508-548-2502, FAX: +1-508-548-6063, E-mail: mcollins@amacad.org or mcollins@whoi.edu

U03 Current Research Employing Accelerator Mass Spectrometry
The development of accelerator mass spectrometry (AMS) heralded a new era in the Earth sciences and, in part, has led to the routine measurement of a suite of isotopes (e.g. 10Be, 14C, 26Al, 36Cl, 99Tc, 129I).  AMS has to some extent come of age and is now in its third decade.  It is considered a necessary analysis tool.  The measurement of natural and man-made nuclides has assisted in answering fundamental questions in the Earth sciences. Some of these include the distribution and variability of oceanic radiocarbon to study circulation and carbon cycling; measurement of specific components isolated from dissolved, sedimentary, or soil organic matter to characterize constituents controlling the carbon cycle; in situ cosmogenic nuclide production to date geomorphic surfaces; the study of groundwater flow and recharge; and detailed paleoclimate chronologies.  We encourage papers presenting novel methodologies, new data sets, interpretations, and applications across the breadth of the earth sciences.
Conveners: Tom Guilderson, Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, L-397, 7000 East Avenue, Livermore, CA  94551 USA, Tel: +1-925-422-1753, Fax: +1-925-423-7884, E-mail: guilderson1@popeye.llnl.gov Department of Earth & Planetary Sciences, 20 Oxford Street, Harvard University, Cambridge MA 02138, FAX: +1-617-496-4387, E-mail: guilderson@eps.harvard.edu Susan Trumbore, Department of Earth System Science, University of California, Irvine, CA 92697 USA, Tel: +1- 949-824-6142, Fax: +1-949-824-3256, E-mail: setrumbo@uci.edu Marc W. Caffee, Lawrence Livermore National Laboratory, L-202, Livermore, CA 94550 USA, Tel: +1-510-423-8395, FAX: +1-510-422-1002, E-mail: caffee1@llnl.gov and Fred Phillips,  Department of Earth and Environmental Science,  New Mexico Tech,  Socorro, NM  87801 USA, Tel: +1-505-835-5634, E-mail: phillips@nmt.edu

U04 Quantifying Predictability in Geophysical Systems I
Quantifying the predictability of nonlinear geophysical systems provides a fundamental bridge between models of geophysical systems and the systems themselves.  Uncertainty in the initial condition and errors in model formulation have led to probability forecasts (ensembles) even in deterministic systems.  This session will focus on atmospheric and ocean dynamics over hours to centuries (e.g., adaptive observation strategies, Lagrangian and Eulerian approaches, intense short duration events); theoretical aspects of the dynamics of nonlinear systems relevant to predictability and verification (including multiple models, contrasting modeling strategies, data assimilation);  and practical issues in the interpretation and likely economic impact of probabilistic forecasts on a timescale of minutes to hours (e.g., precipitation/wind), days to months (e.g., hurricanes), and years to millennia (e.g., earthquakes).  This Union session will consist of invited talks.  Please direct contributed presentations to the special session of the same title - II. Invited Papers Only
Conveners: Leonard Smith, Oxford University, 24-29 St Giles', Oxford, OX1 3LB, United
Kingdom, Tel: +44-1865-270-517, FAX: +44-1865-270-515, E-mail: lenny@maths.ox.ac.uk and
James Hansen, Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Room 54-1721, Cambridge, MA 02139, USA, Tel: +1-617-253-5935, Fax: +1-617-253-6208, E-mail: jhansen@mit.edu

U05 The Discovery of the Sunken Cities of the Alexandria, Egypt, Coast: Archaeology, Earthquakes, Sediments, and Exploration Geophysics
Two ancient sunken cities under the Mediterranean, dating back to Ptolemaic and pharaonic times were recently discovered near Alexandria, Egypt (May 2000).  The most spectacular of these was found in the Bay of Aboukir, east of Alexandria.  Both cities, under 6–7 m of water and 0.5–1.5 m of sand, were discovered by using exploration geophysics methods: an ultrasensitive magnetometric survey, sidescan sonar survey, and high-resolution subbottom profiling survey.  Preliminary excavations under water have revealed numerous collapsed monumental statues, granite columns, and entire walls, strongly suggesting earthquakes as the main cause.  The subsidence of the two cities, as well as portions of Alexandria itself, including the ancient Alexandria harbor and Cleopatra's palace, may also be related to these earthquakes, and possibly also to liquefaction and slumping of the sediments of the Nile delta.  This session will include invited presentations by the archaeologists and geophysicists who made the discoveries. We solicit also other contributions related and/or relevant to this discovery and similar ruins, earthquakes, and subsidence events.
Convener: Amos Nur, Department of Geophysics, Stanford University, Stanford, CA 94305-2215 USA, Tel: +1-650-723-9526, FAX: +1-650-723-1188, E-mail: amos.nur@stanford.edu

U06 Plate-Mantle Interaction and Forces That Move Plates
In its original form, plate tectonics describes the motion of rigid plates over the deeper mantle. Plates were assumed to be essentially decoupled from the deeper mantle by the asthenosphere, driven mainly by slab pull and ridge push (i.e., forces acting on the sides of the plates), and resisted slightly by basal drag. This assumption recently has attained increased attention with the suggestion that basal drag may be an important plate-driving mechanism.  This session focuses on the kinematic and dynamic nature of the coupling between lithospheric plates and underlying mantle. We solicitate contributions presenting observational evidence and theoretical consideration on global or regional scales to constrain plate-mantle interaction.  We anticipate important evidence from stress field constraints, seismic tomography, anisotropy, tectonic studies, gravity, and others.  Geodynamic modeling studies are also welcome, in particular, if they study geodynamic implications involving a strong lithosphere.
Conveners: G. H. R. Bokelmann, Department of Geophysics, Stanford University, Stanford,
CA 94305-2215 USA, Tel: +1-650-725-9181, FAX: +1-650-725-7344, E-mail: goetz@pangea.stanford.edu and Eugene Humphreys, Deprartment of Geology, University of Oregon, Eugene, OR 97403 USA, Tel: +1-503-346-5575, FAX: +1-503-346-4692, E-mail: gene@newberry.uoregon.edu

U07 Global Climate Change: Current Challenges in Research and Scientific Leadership
Global climate change is a focus of both broad interdisciplinary research and intense policy debate.  As increasing numbers of earth scientists become involved in climate-related research and education, they are challenged not only by the need to expand their scientific expertise beyond traditional disciplines, but also by the demand for delivery of cogent scientific information to the public.  New forms of interaction are taking shape.  This session will summarize current research challenges in the form of overview presentations on topics that will be considered in more detail in other meeting sessions.  The conveners of these sessions, and other leaders in the field, will also present their views on the interactions that are required to move forward in both conducting research and in communicating scientific information to the
public.
Convener: Eric T. Sundquist, U.S. Geological Survey, 184 Woods Hole Road, Quissett Campus, Woods Hole, MA 02543 USA, Tel: +1-508-457-2397, Fax: +1-608-457-2310, E-mail: esundqui@usgs.gov

U08 Coping With Uncertainties in Climate Change Research and Policy Activities
Climate change research has become an increasingly complex, interdisciplinary scientific challenge, and many scientists are also working to ensure how scientific advances can be responsive to the needs of policymakers.  This session will be examining some of the key scientific issues facing climate change researchers today, the uncertainties associated with that research, and how these advances and uncertainties can best be used by climate change policymakers.  Speakers will discuss key scientific and policy climate change challenges and how they deal with uncertainties from both the research and policy perspective.
Conveners: Tim Killeen, National Center for Atmospheric Research, Boulder, CO 80307 USA,
Tel: +1-303-497-1111, E-mail: killeen@ucar.edu and Roger Pielke, Jr., National Center for Atmospheric Research, Boulder, CO 80307 USA, Tel: +1-303-497-8111, E-mail: rogerp@ucar.edu
 

U09 Global Change and the Nature of the Earth System
There is increasing evidence that the physical, chemical, and biological cycles of Earth are interlinked and function as a single system, and that human activities are perturbing this system at the global scale.  This session presents the key results of a decade of international research on global change and the Earth system, conducted under the auspices of the International Geosphere-Biosphere Programme.  The session will feature presentations on our latest understanding of the functional role of the three major compartments of the Earth system (oceans, atmosphere, and land) as well as three more integrative talks on (1) the direct linkages between the land surface and the climate system, (2) the dynamics of the global carbon cycle, with special emphasis on human perturbations, and (3) a paleoperspective on Earth system dynamics.    A seventh presentation will point the way toward new, more integrative approaches to Earth system analysis.
Conveners:  Berrien Moore III, Institute for the Study of Earth, Oceans and Space, University of New Hampshire, 39 College Rd., 305 Morse Hall, Durham, NH  03824-3524 USA, Tel: +1-603-862-1766, Fax: +1-603-862-1915, E-mail: b.moore@unh.edu and Will Steffen, Royal Swedish Academy of Sciences, Box 50005, S-10405 Stockholm, Sweden, Tel: +46-8-16-64-48, FAX: +46-8-16-64-05,
E-mail: will@igbp.kva.se

U10 Land-Atmosphere Coupling in the Global Climate System
The land-atmosphere interface is one of the most important elements in the global climate system. This interface drives many processes in the troposphere, and generates an upward-directed microwave signal that can be monitored by satellites and a downward-propagating temperature signal that can be observed in the subsurface. Each phenomenon is the outcome of complex coupled physical, chemical, hydrological and biological processes at this interface. All these processes need to be well represented in numerical models of the climate system, as this interface represents the lower boundary condition of such models for almost 30% of the Earth's surface.  This special session invites contributions addressing one or more aspects of the land-atmosphere interface:  parameterization of land surface processes, coupling to the troposphere, generation of the outward-bound microwave signal, the downward-propagating geothermal
signal, and characterization of hydrological, and biological signatures, at the many spatial and temporal scales that govern such processes.
Conveners:  Hugo Beltrami, Department of Geology, St. Francis Xavier University, Antigonish,
NS, B2G 2W5, Canada, Tel: +1-902-867-2326, Fax: +1-902-867-2457, E-mail: hugo@.stfx.ca or hugo@justine.stfx.ca Roni Avissar, Department of Environmental Sciences, Rutgers University, New Brunswick, NJ 08901-8551 USA, Tel: +1-732-932-9520, Fax: +1-732-932-3562, E-mail: avissar@gaia.rutgers.edu and Henry N. Pollack, Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109 USA, Tel: +1-734-763-0084, Fax: +1-734-763-4690, E-mail: hpollack@umich.edu

U11 The Changing Level of the Sea:  Paleogeodesy, Space Geodesy, and Global Change
Although the focus of most research on global warming has been quite sharply upon the expected increase of mean surface temperature, other aspects of the climate system response to increased greenhouse gas forcing are expected to be equally important.  Of these, global sea level rise is especially deserving of attention, as it integrates the influence of several distinct contributions.  Compelling evidence exists that suggests that the expected anthropogenically forced increase of mean sea level is in fact occurring, although the rate at which this is taking place is a continuing subject of debate.  Contributing to this observed signal is the influence of the steric effect of the thermal expansion of the oceans.  This contribution is augmented by the eustatic effect of the melting of small ice sheets and glaciers, and perhaps also by ablation of the great polar ice sheets on Greenland and Antarctica as well.  None of these contributions to the observed signal of global sea level rise is known to sufficiently high accuracy.  Next- generation satellite missions such as CHAMP and GRACE (NASA's Gravity and Climate Experiment) are expected to contribute in an extremely important way to the understanding of the sea level impact of global climate change.  Substantial input into the interpretation of the time-dependent geoid that will be delivered by these satellite missions will be required from detailed geodynamic analyses of the interactions that occur between ice sheets, oceans, and the Earth's shape as the climate-induced sea level response develops.  Similarly, inputs will be required from modern coupled atmosphere-ocean general circulation models that can be directly employed to predict the local and global rates of sea level rise to be expected on the basis of a particular global warming scenario.  The satellite observations themselves will require "ground-truthing" against surface tide-gauge observations.  We invite contributions to this session on all aspects of the science of global sea level rise that lie on the climate-geodesy interface, especially those that relate to present or future satellite missions.
Conveners: Sydney Levitus, National Environmental Satellite, Data, and Information Service, E/OC5, Bldg. SSMC3, Room 4362, 1315 East-West Hwy., Silver Spring, MD 20910-3282 USA, Tel: +1-301-713-3290 ext. 194, Fax: +1-301-713-3303, E-Mail:  Sydney.levitus@noaa.gov  Mark Meier, Campus Box 475, University of Colorado, Boulder, CO 80303 USA, Tel: +1-303-492-6556, E-Mail: Mark.meier@colorado.edu C. K. Shum, Ohio State University, 222A Bolz Hall, 2036 Neil Ave. Mall, Columbus, OH 43210 USA, Tel: +1-614-292-7118, E-Mail: ckshum@osu.edu Carl Wunsch, Department of Earth, Atmospheric and Planetary Science, Massachusetts Institute of Technology, Cambridge, MA USA, Tel: +1-617-253-5937, Fax: +1-617-253-4464, E-Mail: cwunsch@mit.edu and Richard Peltier, Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada Tel: +1-416-978-2938, Fax: +1-416-978-8905, E-Mail: peltier@atmosp.physics.utoronto.ca
 

Atmospheric Science (A)

A01 Arctic Ozone Depletion and Air-Snow Interactions in the Boundary Layer
Recent evidence from Alert and Summit indicates that interactions between the snowpack and the atmosphere can have a substantial impact on the phenomenon of ozone depletion in the marine boundary layer, first observed at Alert and Barrow.  Specifically, it appears that halogen activation can occur via oxidation of sea salt deposited into the snowpack.  It has also been shown that nitrogen oxides, formaldehyde, and other free radical precursors are emitted from the snowpack, with a significant impact on boundary layer composition.  To study ozone depletion further, in coordination with GOME satellite data retrieval and in association with other projects such as TOPSE, the ALERT2000 campaign was conducted in February–May 2000 at Alert, Nunavut, Canada.  A major focus of ALERT2000 was to investigate air-snow interactions and how they impact on boundary layer composition and chemistry, and the phenomenon of ozone depletion.  In the summer of 2000 a campaign was conducted at Summit, Greenland, also focusing on air-snow interactions.  This session will focus on the results of these most recent field studies in the Arctic.  Contributions from related field studies outside the Arctic, as well as laboratory studies of ice and snow chemistry and physics, and the heterogeneous processes of halogen activation are also solicited.
Conveners: Paul B. Shepson, Purdue University, Departments of Chemistry and Earth and Atmospheric Sciences, 1393 Brown Bldg., West Lafayette, IN 47907-1393 USA, Tel: +1-765-494-7441, Fax: +1-765-494-0239, E-mail: pshepson@purdue.edu.  Jan Bottenheim, Meteorological Service of Canada, 4905 Dufferin Street, Downsview Ontario, Canada M3H5T4; Tel: 416-739-4838; E-mail: jan.bottenheim@ex.gc.ca

A02 Evolution of the Atmospheric Methane Budget (Joint With OS)
The IGBP GAIM core project recently initiated an activity to synthesise information on the atmospheric methane budget from all relevant disciplines. A special session at the AGU Fall meeting is proposed to enable existing participants in this activity to exchange results in a structured way and, importantly, to bring this activity to the attention of a wider range of scientists.   The proposed session would focus on the evolution of the atmospheric methane budget over time. This covers glacial to interglacial transitions, including both abrupt and gradual changes in methane concentration and isotopic ratios observed in ice cores and firn-air, and the more recent evolution from pre-industrial to present conditions. Papers will be invited to either present new analyses of the methane budget at specific times, or to explicitly address the evolution of the budget over time. Topics to be covered will include, but not be restricted to: records of past changes in atmospheric methane; wetland emissions and their changes over time; release of hydrated methane; changes in atmospheric chemistry relevant to methane; and feedbacks between climate change and atmospheric chemistry.
Conveners: Martin R. Manning, National Institute of Water and Atmospheric Research, PO Box 14-901, Wellington New Zealand, (courier address: 301 Evans Bay Parade, Kilbirnie, Wellington), Tel: +64-4- 386-0535, Fax: +64-4-386-2153, E-mail: m.manning@niwa.cri.nz and David M. Etheridge, CSIRO Atmospheric Research, Private Bag 1, Aspendale VIC, 3195, Australia (courier address: 101-107 Station St., Aspendale, Melbourne), Tel: +61- 3-9239-4590, Fax: +61-3-9239-4444, E-mail: david.etheridge@dar.csiro.au

A03 Organic Compounds in Tropospheric Particles and Aqueous Drops (Joint With OS)
Recent field measurements have demonstrated that organic particles are widespread in both continental and marine atmospheres and that they can account for a substantial fraction of the total aerosol number concentration and mass.  There are numerous indications that this organic matter has profound effects on the physical and chemical behavior of aerosols, influencing issues such as cloud properties, precipitation,
climate, and health. Similarly, organic compounds are an important component of tropospheric cloud and fog drops, and can have important effects on both aqueous and gas phase chemistry.  It is now clear that reliable modeling of the effects of organic compounds in atmospheric condensed phases must include better field measurements as well as new laboratory data.
Conveners: Cort Anastasio, Department of Land, Air and Water Resources, University of California, One Shields Ave., Davis, CA  95616-8627 USA, (Express mail:  add "151 Hoagland Hall" to above address), Tel: +1-530-754-6095, Fax: +1-530-752-1552, E-mail: canastasio@ucdavis.edu and Yinon Rudich, Department of Environmental Sciences, Weizmann Institute, Rehovot 76100, Israel, Tel: +972-8-934 4237, Fax: +972-8-934 4124, E-mail: yinon.rudich@weizmann.ac.il

A04 The Arctic and Antarctic Oscillations: Feedbacks and Connections With the Climate System (Joint With OS)
Topics include the basic structure of the Artic and Antartic oscillations, including their unforced variability, and their development over time on scales from days to decades. Contributions concerning either the hemispheric scale modes or regional modes such as the North Atlantic Oscillation are welcome. Phenomena from the ocean to the mesosphere have been implicated in the generation of these oscillations and their response to external forcings. Papers concerned with response or connections between these patterns and the ocean circulation, sea-ice and the lower and upper atmosphere are therefore especially encouraged.
Conveners: Drew Shindell, NASA Goddard Institute for Space Studies, Columbia University, 2880 Broadway, New York, NY  10025 USA, Tel: +1-212-678-5561, Fax: +1-212-678-5561, E-mail: dshindell@giss.nasa.gov and Gavin Schmidt, NASA Goddard Institute for Space Studies, 2880 Broadway, New York, NY 10025 USA, Tel: +1-212-678-5627, Fax: +1-212-678-5552, E-mail: gschmidt@giss.nasa.gov

A05 African Dust Over the Tropical North Atlantic (Joint With OS)
There is increasing interest in the role of mineral dust in atmospheric processes. Of particular interest is the interaction of solar radiation with dust because of the possible impact on climate through the scattering and adsorption of radiation and the modification of cloud properties. Over the ocean these processes also affect our ability to use remote sensing techniques to retrieve various ocean properties such as water temperature and color. The tropical North Atlantic is an excellent location to study these processes because of the very high concentrations of African dust that cover large areas of this region during much of the year.  For this session we are asking for papers that focus on the role of African dust in atmospheric processes. This includes papers that characterize the temporal and spatial variability of dust with respect to meteorological parameters, the chemical and physical properties of dust that relate to radiative processes, and the possible impact on clouds. This session will also serve as a means to present the initial results from the Puerto Rico Dust Experiment (PRIDE), which will take place in June and July 2000.
Conveners: Joseph M. Prospero, Rosenstiel School of Marine and Atmospheric Sciences, 4600 Rickenbacker Causeway, Miami, FL 33149 USA, Tel: +1-305-361-4159, Fax: +1-305-361-4457, E-mail: jprospero@rsmas.miami.edu and Jeffrey S. Reid, SPAWAR Systems Center San Diego, Atmospheric Propagation Branch, Code D858, 49170 Propagation Path, San Diego, CA 92152-7385 USA, Tel: +1-619-553-1419; Fax: +1-619-5531417, E-mail: jreid@spawar.navy.mil

A06 Investigation of Atmosphere-Earth Interactions With Cooperative Atmosphere-Surface Exchange Study 97 and 99 Data (Joint With B)
The main goal of the Cooperative Atmosphere Surface Exchange Study (CASES) is to investigate atmosphere-earth interactions in a mesoscale watershed through long-term observations. Two field
programs, CASES-97 and CASES-99, took place from April 21to June 17, 1997, and during the month of October 1999, respectively. These programs were conducted to study the role of land-surface processes in the diurnal evolution of the convective boundary layer and the nocturnal boundary layer. The
purpose of this session is to discuss the progress and determine issues that need to be addressed for further field experiments. This special session solicits papers on CASES data analysis,  development/validation of land-surface and boundary layer models, and application of CASES data in mesoscale and  general circulation models. Papers on similar topics are also encouraged.
Conveners: Margaret LeMone, Mesoscale and Microscale Meteorology, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307 USA, Tel: +1-303-497-8962, Fax: +1-303-497-8171, E-mail: lemone@ucar.edu Fei Chen, Research Applications Program, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307 USA, Tel: +1-303-497-8454, Fax: +1-303-497-8401, E-mail: feichen@ucar.edu and Jielun Sun, Mesoscale and Microscale Meteorology, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307 USA, Tel: +1-303-497-8994,
Fax: +1-303-497-8171, E-mail: jsun@ucar.edu

A07 Cumulus Convection and Climate
Cumulus convection is one of the most important mechanisms controlling the content and vertical distribution of atmospheric water vapor, the most important greenhouse gas present in the Earth's atmosphere. Despite substantial progress in the development of global climate models (GCMs) during the last three decades, cumulus convection is still one of the least accurate physical processes included in current GCMs. In these models the mean climate and its variability are very sensitive to the parameterization of cumulus convection. Moist convection is also the main atmospheric source of diabatic heating. However, only a small fraction of this heating is converted into kinetic energy and is ultimately consumed by frictional dissipation. The value of this fraction, which represents the thermodynamic efficiency of moist convection, is still controversial. There is evidence that moist convection is more irreversible than dry convection, and that numerical models might be more dissipative than nature. Contributions to this session will cover observational, theoretical, and modeling aspects of cumulus convection and its influence on climate.
Convener: Nilton O. Renno, Atmospheric Science Department, University of Arizona,
P.O. Box 210081, Tucson, AZ 85721-0081 USA, Tel: +1-520-621-6016, Fax: +1-520-621-6833, E-mail: renno@atmo.arizona.edu

A08 SAGE III Ozone Loss and Validation Experiment (SOLVE) and the Third European Stratospheric Experiment on Ozone-2000 (THESEO-2000) Missions
The SAGE III Ozone Loss and Validation Experiment (SOLVE) was designed to examine the processes controlling ozone levels at mid- to high latitudes.  SOLVE was also carefullly coordinated with the Third European Stratospheric Experiment on Ozone-2000 (THESEO-2000) mission.  Measurements were made in the Arctic high-latitude region over the course of the 1999-2000 winter using the NASA DC-8 and ER-2 aircraft, as well as balloon platforms and ground-based instruments. The OLVE/THESEO-2000 campaign was the larges polar stratospheric measurement campaign conducted to date. Ozone losses during the Arctic winter of 1999-2000 exceeded 60%.  These large losses were obseved by aircraft, balloon, and satellite measurements.  Meteorological analyses reveal that the 1999-2000 winter
was colder than normal.  These temperatures were cold enough to produce extensive layers of polar stratospheric clouds (PSCs).  PSCs are key ingredients of the ozone loss process, as they enable the conversion of chlorine from benign forms into reactive forms that can catalytically destroy ozone.
Conveners: Paul A. Newman, Code 916 NASAGoddard Space Flight Center, Greenbelt, MD 20771 USA, Tel: +1-301-614-5985, Fax: +1-301-614-5903, E-mail: newman@notus.gsfc.nasa.gov

A09 Kinetics and Mechanism of Hydrocarbon Oxidation Reactions
Photochemical oxidation of atmospheric volatile compounds (VOCs) leads to ozone, aerosol, and carbon dioxide formation, with major implications for local and regional air quality and global climate changes. For example, the chemistry of the urban atmosphere is characterized primarily by ozone formation, through the oxidation of hydrocarbons initiated by inorganic oxidants in the presence of nitrogen oxides. Also, the VOC oxidation reactions lead to an increase in atmospheric aerosol loading by gas-to-particle conversion. Currently there are still major uncertainties associated with the VOC chemistry. This session invites papers on kinetic and mechanistic studies relevant to atmospheric photochemical oxidation of VOCs.
Convener: Renyi Zhang, Tel: +1-979-845-7656, Fax: +1-979-862-4466, E-mail: zhang@ariel.tamu.edu

A10 Convective Systems Observed During TRMM Field Campaigns
Recently completed TRMM field campaigns (TEFLUN-1998, SCSMEX-1998, TRMM-LBA-1999, and KWAJEX-1999) have obtained direct measurements of microphysical data associated with convective systems from various geographical locations  (Texas/Florida, South China Sea, Amazonia, and Kwajalein, respectively). These TRMM field experiments were designed to contribute to fundamental understanding of cloud dynamics and microphysics, as well as for validation, testing assumptions and error estimates of
cloud-resolving models, forward radiative transfer models, algorithms used to estimate rainfall statistics and vertical structure of precipitation and latent heating from both surface-based radar and satellites.
Contributions to this session would encompass all aspects (observational, modeling, and remote sensing) of convective systems associated with TRMM field campaigns.  These topics would include descriptions of microphysics, thermodynamics and dynamic structures, radar reflectivity, and rainfall characteristics and statistics.  New results on the role of aerosols and CCN in cloud physics and dynamics are also encouraged.  The topics also include the sensitivity of microphysical assumptions in the cloud resolving models and forward radiative transfer models, and rainfall comparisons (statistics and errors) between  ground based platforms, aircraft, and estimates from TRMM.
Conveners: Edward J. Zipser, Meteorology Department, University of Utah, 135 South 1460 East, Room 819, Salt Lake City, UT 84112-0110 USA, Tel: +1-801-585-9482, Fax: +1-801-585-3681, E-mail: ezipser@met.utah.edu and Wei-Kuo Tao, Laboratory for Atmospheres, NASA Goddard Space Flight Center, Greenbelt, MD 20771 USA, Tel: +1-301-614-6269, Fax: +1-301-614-5492, E-mail: tao@agnes.gsfc.nasa.gov

A11 NOAA Postdoctoral Program in Climate and Global Change  (Joint With B, OS)
The purpose of the program is to help create and train the next generation of researchers needed for  climate studies.  It was anticipated that several contemporary National Oceanic and Atmospheric Administration (NOAA) efforts, such as TOGA and its ambitious field programs (e.g., COARE), would undoubtedly generate a tremendous amount of data that would require the attention of an enlarged research community here and abroad.  In the larger view, it was necessary to attract some of the new Ph.D.’s to the community in order to establish the seeds of scientific leadership for the extended programs of the future.  Thus, the program endeavors to attract outstanding recent Ph.D.’s in the sciences relevant to the NOAA Climate and Global Change Program.  The program supports research on climate variations with timescales of seasons to centuries.  This is the 10th year of this very successful fellowship program.  We propose to mark the event by holding a half-day afternoon session at the AGU Fall Meeting with a reception immediately following a series of invited talks.  We envision that the afternoon would consist of the following: one 20 minute talk that summarizes the history and scope of the program, and nine invited talks (20 minutes each) from past and present participants in the program who gone on to become leaders in various disciplines. The topic of each talk will be influenced heavily by the speaker, so that each talk will be cutting-edge research, with many of the talks likely to be on "hot topics." (The talks are not to be a review of what the speaker did while he/she was a postodc in the program.) Both the reputations of the speakers and the topics should ensure that this will be a very well attended session.
Conveners: David Battisti, Department of Atmospheric Sciences, University of Washington, Box 351640
Seattle, WA  98195-1640 USA, Tel: +1-206-543-2019, Fax: +1-206-543-0308, E-mail: david@atmos.washington.edu Daniel P. Schrag, Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street Cambridge, MA  02138 USA, Tel: +1-617-495-7676, Fax: +1-617-496-4387, E-mail: schrag@eps.harvard.edu

A12 Sun-Climate Connections (Joint With SA)
A renewed interest in the study of mechanisms behind possible links between solar variability and climate has taken place in the last half-decade.  Study results have been reported in recent meetings, such as the AGU 1998 Fall Meeting and the 1999 annual meeting of the International Union of Geodesy and Geophysics.  A National Aeronautics and Space Administration-sponsored workshop was held in March 2000 to examine the breadth of current research and how it might suggest preferred directions and future research strategies  (http://www.ispe.arizona.edu/conferences/sunmeet/).  Workshop conclusions will be presented in invited presentations, and papers are invited on all aspects of study related to hypothesized mechanisms linking solar variability with climate variability and change.
Convener: William A. Sprigg, Institute for the Study of Planet Earth, University of Arizona, 715 N. Park Ave., Tucson, AZ 85721 USA, Tel: +1-520-622-9062 or 9014, Fax: +1-520-792-8795, E-mail: wsprigg@u.arizona.edu

A13 Air Pollution - Dry Air-Surface Exchange
Dry air-surface exchange addresses both deposition and emission of trace substances.  Dry deposition can account for a large portion of the removal of gases and a significant amount of particulate material from the troposphere over regional or larger scales. Biogenic emission of reactive hydrocarbons alters tropospheric chemistry in some areas.  The long-term net exchange of greenhouse gases such as carbon dioxide regulates their concentrations in the atmosphere.  Contributions to this session would encompass all aspect of dry air-surface exchange, including observations made in the field both at the surface and aboard research aircraft, development of chemical instrumentation, parameterization of processes at the surface and aloft, rapid in-air chemical reactions, modeling over scales ranging from urban to global, and scaling up or down between surface elements and landscapes.  Special topics of  interest include evaluation of methods to measure nighttime fluxes of various substances, including carbon dioxide; the role of lipid solubility in affecting the deposition and possible subsequent remission of organic gases; and particle deposition as a function of particle size, turbulence level, and the geometry and wetness of
surface elements.
Conveners: Jie Song, Meteorology Program, Department of Geography, Northern Illinois University, DeKalb, IL 60115 USA, Tel: +1-815-753-6837, Fax: +1-815-753-6872, E-mail: jsong@geog.niu.edu  Marvin L. Wesely, Environmental Research Division, Building 203, Argonne National Laboratory, Argonne, IL 60439 USA, Tel: +1-630-252-5827, Fax: +1-630-252-5498, E-mail: mlwesely@anl.gov

A14 Integration of Ozone and Particle Formation Processes - A Tale of Two Cities
Linkages and synergism among processes and precursors leading to formation of tropospheric ozone and aerosols have been recognized before but rarely studied in an integrated way.  During the summer of 1999, more than 200 scientists, engineers, and graduate students from 40-plus institutions in North America and Europe converged on Nashville, Tennessee and Atlanta, Georgia to study these linkages and synergisms.  Armed with a small armada of aircraft- and ground-based platforms and one of the most sophisticated arrays of particle-characterization instrumentation ever assembled in the United States, the Southern Oxidants Study (SOS) established an Initial EPA Supersite in Atlanta and completed its second rural-urban exchange study in the 11-state area surrounding Nashville. The SOS summer 1999 field experiments provided a wide diversity of meteorological conditions and a suite of varying anthropogenic and biogenic emissions.  The first public presentation of scientific findings from these studies will be made at the AGU Fall Meeting. Issues to be discussed include development and intercomparisons of gas-phase and particulate measurement methods; the diurnal, daily, and week-by-week variability of pollutants in the southeastern United States; the chemical and physical characteristics of millions of single particles, each discretely measured and characterized; model simulations; and analysis of aircraft- and ground-based measurements to better understand processes that control formation and distribution of ozone and fine particles in urban and rural areas.  The results from these integrated studies have special significance in light of the Environmental Protection Agency’s recent decisions to tighten the National Ambient Air Quality Standard (NAAQS) for ozone and to add a new NAAQS for PM2.5.
Conveners: William Chameides, School of Earth and Aeronomy Laboratory, Georgia Tech, Atlanta, GA 30332-0340 USA, Tel: +1-404-894-1949, Fax: +1-404-894-1106, E-mail: wcham@eas.gatech.edu
James Meagher, Aeronomy Laboratory, National Oceanic and Atmospheric Administration,
Boulder, CO 80303 USA, Tel: +1-303-497-3605, Fax: +1-303-497-5373, E-mail: jmeagher@al.noaa.gov and Ellis Cowling, College of Forest Resources, 1307 Glenwood Ave., Suite 157, North Carolina State University, Raleigh, NC 27695 USA, Tel: +1-919-515-7564, Fax: +1-919-515-1700, E-mail:  ellis_cowling@ncsu.edu

A15 Atmospheric Results From the Terra Spacecraft
The NASA Earth Observing System Terra spacecraft (formerly designated as EOS AM-1) is the first of the larger Earth Observing System spacecraft. It was launched on December 18, 1999, exactly 1 year before this year's Fall Meeting.  Four of the instruments, CERES (Clouds and the Earth's Radiant Energy System), MISR (Multi-angle Imaging Spectroradiometer), MODIS (Moderate-Resolution Imaging Spectroradiometer), and MOPITT (Measurements of Pollution in the Troposphere), are providing large amounts of new data on the atmosphere. For this session we solicit papers that describe the results of activities to validate the data, and the scientific results of these new observations.
Conveners: John Gille, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-3000 USA, (Express mail:  3300 Mitchell La., Suite 275, Boulder, CO 80301 USA), Tel: +1-303-497-8062, Fax: +1-303-497-2920, E-mail: gille@ucar.edu Yoram Kaufman, NASA Goddard Space Flight Center, Code 913, Bldg. 33, Room A308, Greenbelt, MD 20771 USA, Tel: +1-301-614-6189, Fax: +1-614-6307, E-mail: kaufman@climate.gsfc.nasa.gov

A16 Detection and Attribution of Climate Change
Proxy evidence suggests that the 20th century is the warmest of the last millennium. The six warmest  years of the last century all occurred in the 1990s. Climate models predict rapid climate change over the next few decades, with a predicted warming of roughly 3 degrees by the end of the 21st century. Climate change during the 20th century was far from uniform: There was a period of rapid warming in the 1920s and 1930s, followed by relatively stable global mean temperatures until the mid 1970s, when warming resumed. Papers documenting observed climate change on continental-to-global scales, techniques to detect and attribute causes of climate change, and studies ascribing causes are all solicited. Also welcome are papers that consider observational and model uncertainty on continental-to-global scales, as well as papers that compare observations with simulation results and use such comparisons to gain information on uncertainties in model-based projections of future climate change.
Conveners:  Simon Tett, Hadley Centre for Climate Prediction and Research, Meteorological Office, London Rd., Bracknell RG12 2SY, UK, Tel: +44- 0-1344-856886, Fax: +44-0-1344-854898,E-mail: www.met-office.gov.uk Benjamin D. Santer, Program for Climate Model Diagnosis and Intercomparison, Lawrence Livermore National Laboratory, PO Box 808, Mail Stop L-264, Livermore, CA 94550 USA, Tel: +1-925-422-7638, Fax: +1-925-422-7675, E-mail: santer1@llnl.gov

A17 Historical Session on Hurricanes:  100 Years Since “Galveston”
Three sessions, anchored historically in the Galveston hurricane of 1900, the greatest natural disaster in United States history, will address the impact of science and technology during the last 100 years on our ability to cope with the hurricane threat in U.S. coastal areas. In the first two sessions, 10 invited speakers will describe and evaluate the progress made in understanding the hurricane, in communicating risks and immediate threats to the public, roadblocks encountered in research, and the outlook for the future.
For the third session, we encourage poster presentations that will provide additional historical accounts, and descriptions of current researches on hurricanes and the expected impacts.
Convener: Robert H. Simpson, 540 N St., SW, #S-803, Washington, DC  20024 USA, Tel: +1-202 479-0052, E-mail: r.h.simpson@worldnet.att.net

B04 Halocarbons: Global Biogeochemistry and Contaminant Transformations (Joint With A, OS)
This special session will broadly cover topics in halocarbon research including sources and sinks of halogenated compounds in oceanic, freshwater and terrestrial environments, biogeochemistry of trace atmospheric halocarbons, and transformations of halogenated contaminants. Abstracts are solicited from all disciplines involved in the study of abiotic or biological processes that influence the fate of  halocarbons. Suggested topics include rates and mechanisms of production/consumption in pristine or impacted environments, degradation studies including flowpath modeling, isotopic investigations of source/sink signatures, and examination of processes that control the distribution of halocarbons in the atmosphere.
Conveners: Larry Miller, U.S. Geological Survey, MS 465, 345 Middlefield Rd., Menlo Park, CA  94025 USA, E-mail: lgmiller@usgs.gov Kelly Goodwin, Tel: +1-650-329-4475, Fax: +1-650-329-4327,
E-mail: goodwin@aoml.noaa.gov

B09 The Role of Fire in the Boreal Forest and Its Impacts on Climatic Processes (Joint With A, NG)
Boreal forests account for about a third of the carbon sequestered in terrestrial ecosystems, so changes in their functioning or distribution could create important feedbacks to the climate system. Changes in the extent of forest cover could alter regional energy budgets sufficiently to amplify or nullify the expected rapid climatic warming at high latitudes. Warming could cause boreal forests to change from being a component of the "missing sink" of carbon dioxide to being a net source if fire frequency or decomposition increases. The rate of change in boreal forests is governed by fire frequency and severity, with important effects on carbon and energy flows. In the boreal forests several feedback mechanisms must be quantified to fully understand the role of fire in influencing landscape response to a changing climate. Some topics that this session will address are (1) changes in carbon stocks caused by immediate off-site transfer during the fire and by changes in decomposition and production following fire; (2) changes in energy budgets caused by fire; and (3) changes in the structure of the ecosystem, with associated changes in carbon or energy budgets.
Conveners: Larry Hinzman, Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK 99775-5860 USA, Tel: +1-907-474-7331, Fax: +1-907-474-7979, E-mail: ffldh@uaf.edu   F. Stuart Chapin, Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775 USA, Tel: +1- 907-474-7922, Fax: +1-907-474-6716, E-mail: fschapin@bonanza.lter.uaf.edu

B10 Land-Atmosphere Interactions, I, Arctic Transitions (Joint With A, H)
This session will focus on spatial and temporal patterns and controls over land-atmosphere surface exchange of mass and energy in arctic tundra and in transition regions between arctic tundra and boreal forest. High-latitude ecosystems play an important role in the functioning of the earth system because they occupy a large area; are sensitive to changes in climate; influence the exchanges of water, energy, and radiatively active gases with the atmosphere; and affect regional and global climate.  Functional responses of arctic tundra to climate variability and change have the potential to influence global climate through the exchange of radiatively active gases with the atmosphere. Spatial variation in vegetation within arctic tundra has substantial climatic effects that extend beyond tundra. Structural responses, which include treeline changes and vegetation changes associated with fire, may substantially alter water and energy exchange in transitional regions of arctic and boreal vegetation to influence regional climate. Abstracts are solicited on relationships among vegetation, soils, permafrost, snow, and climate in arctic regions that have implications for regional and global climate.
Conveners: A. David McGuire, Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775 USA, Tel: +1-907-474-6242, Fax: +1-907-474-6716, E-mail: ffadm@uaf.edu Matthew Sturm, U.S. Army Cold Regions Research and Engineering Laboratory, PO Box 35170, Ft. Wainwright, AK 99703-0170 USA, Tel: +1-907-353-5183, Fax: +1-907-353-5142, E-mail: msturm@crrel41.crrel.usace.army.mil

B11 Land-Atmosphere Interactions, II, North Africa (Joint With A, H)
This session focuses on the interactions between the atmosphere and the terrestrial biosphere over north Africa as well as change and variability of the coupled biosphere-atmosphere-ocean system. Relevant  topics include, but are not limited to, the natural coevolution of the biosphere-atmosphere system; the  influence of the ocean, in particular sea surface temperatures and their variability, on the biosphere-atmosphere interaction; the role of the terrestrial biosphere in both the modern climate and the paleoclimate; reconstruction of paleoclimate; impact of anthropogenic land cover changes.
Conveners: Guiling Wang, Princeton Environmental Institute, 27 Guyot Hall, Princeton University, Princeton, NJ 08544-1003 USA, Tel: +1-609-258-3511, E-mail: gwang@princeton.edu Martin Claussen, Potsdam Institute for Climate Impact Research, PO Box 601203, 14412 Potsdam, Germany, Tel: +49-331-288-2522, Fax: +49-331-288-2600, E-mail: claussen@pik-potsdam.de

B12 Responses of Soil Processes to Elevated Atmospheric CO2 (Joint With A)
Research on the responses of ecosystems to elevated atmospheric CO2 has resulted in a wealth of information. While some consensus can be found regarding aboveground responses to elevated atmospheric CO2, many questions remain on the magnitude, and even the direction of changes in soil carbon and nutrient cycling and soil microbial feedbacks. Understanding the response of soil processes to
elevated CO2 is important, because these processes can strongly influence both the short-term and long-term responses of ecosystems to elevated CO2. Soil processes are difficult to observe, and the variety of measurement techniques often complicates direct comparison of results. Recent studies on understanding responses of belowground processes to elevated atmospheric CO2 are the subject of this session. Some of the important topics that may be addressed include (1) soil microbial feedbacks and microbial biomass turnover; (2) carbon and nutrient cycling and availability, including 15N and 13C isotopic tracer studies; (3) litter decomposition and SOM turnover; (4) changes in soil biology; and (5) trace gas fluxes.
Conveners: Jennifer King, USDA Agricultural Research Service, PO Box E, Fort Collins, CO, 80522 USA, Tel: +1-970-490-8255, Fax: +1-970-490-8213, E-mail: jyking@lamar.colostate.edu Bruce Hungate, Department of Biological Sciences, Northern Arizona University, Box 5640, Flagstaff AZ 86011-5640 USA, Tel: +1-520-523-0925, Fax: +1-520-523-7500, E-mail: bruce.hungate@nau.edu Arvin Mosier, USDA-Agricultural Research Service, PO Box E, Fort Collins, CO 80522 USA, Tel: +1-970-490-8250, Fax: +1-970-490-8213, E-mail: amosier@lamar.colostate.edu

B13 Ecological Component of Large Scale Biosphere-Atmosphere Experiment (LBA) (Joint With A)
This session deals with studies related to the question "How do tropical forest conversion, regrowth, and selective logging influence carbon storage, nutrient dynamics, trace gas fluxes, and the prospect for sustainable land use in the Amazon region?" “Forest conversion” refers to forest clearing and conversion to agricultural uses, especially cattle pasture, and "forest regrowth" refers to forest growth following the abandonment of agricultural lands.  The ecological component of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) includes studies of the effects of these land cover and land use changes on terrestrial carbon and nutrient budgets, the fluxes, of trace gases between the land and the atmosphere, and the exchange of materials between the land and river systems.  Implicitly, the understanding effects of land use changes requires an understanding of these budgets, fluxes and exchanges in "primary" or predisturbance forest ecosystems.
Convener: Michael Keller, LBA-Ecology, Complex Systems Research Center, University of New Hampshire, Durham, NH  03824 USA, Tel  +1-603-862-4193, Fax  +1-603-862-0188, E-mail: lba.ecology@unh.edu

B14 Land Use Change, I, A Paleoenvironmental Perspective on Ecosystem Sustainability (Joint With A)
During the last two millennia, virtually all ecosystems, both managed and quasi-natural, have been subjected to greater fluctuations of climate than are captured by instrumental records. Over the same time span, human impacts on ecosystems have varied and, in many cases, increased dramatically. Documenting, understanding, and distinguishing the role of both types of processes, and the interactions between them, in generating contemporary ecosystems are vital for developing any realistic sense of future sustainability. Case studies from specific ecosystems and regions, as well as model simulations of ecosystem responses, are required. The session will seek to (1) present case studies illustrating the value of paleoecological studies in understanding ecosystem responses to climate change and human impacts; (2) demonstrate appropriate and effective uses of paleoecological data in ecosystem management, conservation, and restoration; and (3) foster development of a robust research and applied framework for maximizing the contribution of paleoecological information to understanding and enhancing future sustainability.
Conveners:  Frank Oldfield, PAGES International Project Office, Barenplatz 2,CH-3011 Bern, Switzerland, Tel: +41-31-312-3133, Fax: +41-31-312-3168, E-mail:  frank.oldfield@pages.unibe.ch  Constance Millar, USDA Forest Service, PSW Research Station, 800 Buchanan St., Albany, CA 94710 USA, Tel: +1-510-559-6435, Fax: +1-510-559-6499, E-mail: cmillar@fs.fed.us

B15 Land Use Change, II, Global Land Use and Land Cover Change Over the Last 300 Years (Joint With A)
Past changes in land use and land cover have impacted climate at regional to continental scale, significantly modified atmospheric carbon concentrations, and created much of the landscape upon which future global change will act. It is therefore becoming increasingly urgent to characterize and quantify these changes, especially for the last 300 years, using all the methods available, ranging from pollen analysis to documentary evidence. The session will summarize recent progress in reconstructing the history of recent land use and cover change resulting from the International Geosphere-Biosphere Programme’s PAGES/LUCC BIOME 300 and other initiatives, and outline the major consequences of the results obtained so far.
Convener:  Frank Oldfield, PAGES International Project Office, Barenplatz 2, CH-3011 Bern, Switzerland, Tel: +41-31-312-3133, Fax: +41-31-312-3168, E-mail: frank.oldfield@pages.unibe.ch Rik Leemans, National Institute of Public Health and Environment, Bureau of Environment and Natural Resources, Antonie van Leewenhoeklaan 9, PO Box 1, NL-3720 BA Bilthoven, Netherlands, Tel: +31-30-274-3377, Fax: +31-30-885-7357, E-mail: rik.leemans@rivm.nl

B16 Biospheric Results from Terra, NASA’s Earth Observing System (Joint With A, H, OS)
The launch of National Aeronautics and Space Administration's Earth Observing System (EOS) Terra on December 18, 1999, marked a new phase of climate and global change research, especially for increased understanding of the interaction of the land and ocean biology with climate.  Terra has scientific instruments to gain information about the Earth's land, oceans, and atmospheres with unprecedented accuracy. Of the five scientific instruments, three are germane to land and ocean remote sensing: the Moderate Resolution Imaging Spectroradiometer (MODIS), the Multiangle Imaging Spectroradiometer  (MISR), and the Advanced Spaceborne Thermal Emission and Reflection Radiometer  (ASTER). This session would focus on results of biospheric research utilizing the Terra spacecraft. Invited papers will be concerned with results of using Terra instruments (MODIS, MISR, and ASTER) for land cover and change, vegetation attributes such as leaf area index and absorptance of photosynthetically radiation, and links into ecosystem models. Recent work by the oceans community regarding chlorophyll and productivity will also be solicited to make the session representative of Terra's biospheric science research.
Convener:  Jon Ranson, Biospheric Sciences Branch, NASA Goddard Space Flight Center, Code 923, Greenbelt, MD 20771 USA, Tel: +1-301-614-6650, Fax: +1-301-614-6695, E-mail: jon.ranson@gsfc.nasa

OS06 Redox Processes in Oxygen Deficient Regions of the Ocean (Joint With A, B)
Recent research cruises to locations such as the Arabian Sea, the eastern tropical North Pacific, and the Cariaco Basin have heightened interest in redox processes occurring in oxygen-deficient regions of the ocean. In particular, these environments are sources of atmospheric greenhouse gases such as nitrous oxide, and their sedimentary records may contain valuable paleo-oceangraphic indicators. This session aims to provide a venue for a wide-ranging discussion of the biogeochemistry of these intriguing environments, their affect on global biogeochemical cycles, and the information that their sediments record.
Conveners: Frank Sansone, Oceanography Department, University of Hawaii, 1000 Pope Rd., Honolulu, HI  96822 USA, Tel: +1-808-956-8370, Fax: +1-808-956-7112, E-mail: sansone@soest.hawaii.edu Mary Scranton, Marine Sciences Research Center, State University of New York at Stony Brook, Stony Brook, NY 11794-5000 USA, Tel: +1-631-632-8735, E-mail: mscranton@notes.cc.sunysb.edu

OS12 Air-Wave-Sea Interaction (Joint With A, NG)
Momentum and energy transfers across the air-sea interface under realistic ocean conditions are important not only in theoretical studies, but also in many applications, including marine and oceanic forecast and climate modeling on all scales. Most difficulties that arise in air-sea coupling studies are at the interface (the surface wave layer) of the two fluids. Surface waves are believed to be an important supplier of turbulent energy, besides shear production of the classical turbulence theory. Recent theoretical and experimental studies have contributed to a better understanding of the complex wind-wave-turbulence-current relationship. Therefore, surface wave parameterization and wave-dependent surface characteristics (roughness length, drag coefficient, turbulent dissipation), taking into account the wind-wave-turbulence-current relationship, have a very important role, not only in small-scale models, but also in larger scale forecast and climate models. Lately, air-wave-sea coupled systems have been developed by various national and international groups using a different coupling physics. This special section will be a forum to exchange ideas and results between marine and oceanic small scale and larger scale coupled modeling and experimental researchers.
Convener: Le Ly, Department of Oceanography, Naval Postgraduate School, Code Oc/Le, Monterey,CA 93943 USA, Tel: +1-831-656-3257, Fax: +1-831-656-2712, E-mail: lely@nps.navy.mil

OS18 Oceanic and Atmospheric Climatologies of the Americas (Joint with A)
This session invites papers reporting on new results in the development of oceanic and atmospheric climatologies. We wish to focus mainly on the question of how these products are used to investigate the climate variability of the Americas.
Conveners: Edgar G. Pavia, CICESE, a.p. 2732, PO Box 434844, Ensenada, B.C. 22800, Mexico, Tel: +526-1745050 x 24060, Fax: +526-1750547, E-mail: epavia@cicese.mx James J. O'Brien, 2035 E. Paul Dirac Dr., R.M. Johnson Bldg., Suite 200, Tallahassee, FL 32310 USA, Tel: +1-850-644-4581, Fax: +1-850-644-4841, E-mail: obrien@coaps.fsu.edu

OS21 Southern Ocean and Climate Change: Past and Future Perspectives (Joint With A)
One of the important new findings in climatology is warming of the ocean, including its abyss, by a rate of a half degree celsius or more per century. This ocean warming over the last several decades reflects the linkage between the ocean thermohaline history and global climate change. Historical observations and paleoclimate data reveal significant climate variability on time-scales of decades to millennia. The North Atlantic and its associated deepwater formation has been the consensus focal point of this variability for decades. However, new analyses indicate that the southern deepwater source can change dramatically (e.g., experience a decrease of as much as two-thirds during the last 800 years). Such changes can substantially alter the millennial pattern of ocean circulation. For example, it is believed that the Little Ice Age was caused by stronger formation of the Antarctic Bottom Water compared to today. It has also recently been discovered that the Southern Hemisphere led Northern Hemisphere changes during parts of the glacial cycles of Pleistocene, implying a seesaw-type oscillation of the global ocean conveyor. Additionally, global warming-related melting of sea ice and ice sheets in Antarctica has the potential to cause a further slowdown of the southern deepwater source. These results demand a better assessment of the role of the Southern Ocean in driving changes of the global ocean circulation and climate. Hence, the Southern Ocean impact on climate is becoming a new focal point of study, presenting new challenges to climatologists, paleoclimatologists, glaciologists, oceanographers, and paleoceanographers in their effort to understand the past and to forecast future alterations of the climate system. This is a high-priority interdisciplinary problem. Observational, proxy data, modeling, and synthesizing papers addressing any aspect of the Southern Hemisphere climate dynamics and Southern Ocean impact on climate in the Late Quaternary, during the Little Ice Age, at present, and in near future will be welcomed.
Conveners: Dan Seidov, Earth System Science Center, Pennsylvania State University, 2217 Earth-Engineering Science Bldg., University Park, PA 16802-6813 USA, Tel: +1-814-865-1921, Fax: +1-814-865-3191, E-mail: dseidov@essc.psu.edu Eric Barron, Earth System Science Center, Pennsylvania State University, 2217 Earth-Engineering Science Bldg., University Park, PA 16802-6813 USA, Tel: +1-814-865-1921, Fax: +1-814-865-3191, E-mail: eric@essc.psu.edu Thomas Stocker, Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland,  Tel: +41-31-631-44-64, Fax: +41-31-631-87-42, E-mail: stocker@climate.unibe.ch

OS22 Linking Climate Variability and Coastal Processes (Joint With A, B, H)
Climate variability, occurring across a range of time-scales, significantly impacts geologic, hydrologic, hydrodynamic, and biologic processes acting in the coastal zone. As climate varies in the future, changes in the intensity, frequency, and location of storms, distribution of rainfall, rate of sea level rise, and water temperature will drive changes in river discharge, nearshore sediment transport, shoreline erosion, and nutrient supply. This session seeks to explore such links between climate variability and coastal processes across a range of time-scales and disciplines as observed in the past and predicted for the future. Abstracts linking climatic and coastal processes are solicited from all relevant disciplines of the natural sciences. Abstracts exploring the societal impacts of changes in coastal processes driven by climate variability are also welcomed.
Conveners:  Laura J. Moore, Geology and Geophysics Department, Woods Hole Oceanographic Institution, MS 22, Woods Hole, MA 02543 USA, Tel: +1-508-289-3597, Fax: +1-508-457-2187, E-mail: lmoore@whoi.edu; Philip Mote, JISAO/SMA Climate Impacts Group, University of Washington, Box 354235, Seattle WA 98195 USA, Tel: +1-206-616-5346, Fax: +1-206-616-5775, E-mail: philip@atmos.washington.edu

P01 Planetary Atmospheric Processes and Astrobiology (Joint With A, B, SA)
Trace gases in the atmosphere react photochemically with important implications for the origin, evolution, and future of life. Many trace gases are generated by biological processes, and they in turn influence ecosystem interactions in the evolution of living systems. Ideas from strochemistry may benefit planetary atmospheric chemistry. The proposed session, therefore, will bring together planetary scientists, aeronomers, astrochemists, and solar scientists to discuss chemical and physical processes from their respective disciplines that may enhance our understanding of astrobiology. It will emphasize topical matters like our terrestrial biosphere and the present or past life on other worlds, particularly on Mars and Europa.
Conveners: Christopher P. McKay, Space Science Division, NASA Ames Research Center, MS 245-3, Moffett Field, CA 94035 USA, Tel: +1-650-604-6864, Fax: +1-650-604-6779, E-mail: cmckay@cmckay.arc.nasa.gov Sheo S. Prasad, Creative Research Enterprises, 6354 Camino del Lago, Pleasanton, CA 94566 USA, Tel: +1-925-426-9341, Fax: +1-925-426-9417, E-mail: ssp@CreativeResearch.org Edward C. Zipf, Department of Physics and Astronomy, University of Pittsburg, Pittsburgh, PA 15260 USA, Tel: +1-412-624-9263 or 412-963-6493, Fax: +1-412-963-0603,
E-mail: Edczipf@aol.com

SA01 The Mesosphere/Lower Thermosphere Region: Structure, Dynamics, Composition, and
Emission (Joint With A)
The Mesosphere and Lower Thermosphere (MLT) between 50 and 150 km is a complex region where a variety of processes are important. Papers in this session explore this variety and highlight the interactions between radiative process, chemistry, wave dynamics, turbulence, electrodynamics, and nonlinear processes.  Contributions related to MLT coupling from regions above and below are also encouraged.
Conveners: Christian Meyer, Colorado Research Associates, 3380 Mitchell La., Boulder, Colorado 80301 USA, Tel: +1-303-497-8328, Fax: +1-303-497-8328, E-mail: meyerc@ucar.edu Daniel Marsh, National Center for Atmsopheric Research, 3450 Mitchell La., Boulder, Colorado 80301 USA, Tel: +1- 303-497-1566, Fax: +1-303-497-1589, E-mail: marsh@ucar.edu

V05 Observation and Modeling of Volcanic Eruptions and Their Atmospheric Effects (Joint With A)
This session aims to bring together noted volcanologists and atmospheric scientists. The topics will span plume behavior with focus on ash deposition, trace gas transport (which may be important, for example, for the tropospheric and stratospheric sulphur budget), interaction of different phases of water with ash and gas, impact of environmental conditions on the plume behavior, and stratospheric injection of trace gases  (SO2, H2S, Cl, Br, H2O). Further, we should include the modeling of the fate of these trace gases in the stratosphere (and the troposphere) all the way to chemical (ozone), radiative, and climate effects. Contributions should cover these topics both from the point of observations and modeling, from eruption   to atmospheric effects. This opportunity should be used to make clear the big omissions in our understanding of these processes and help overcome the one-sided use of volcanological and atmospheric findings.
Conveners: Hans-F. Graf, Max Planck Institute for Meteorology, Bundesstr. 55, D-20146 Hamburg Germany,  Tel: +49-40-41173247, Fax: +49-40-441787, E-mail: graf@dkrz.de Bill Rose, Geological Engineering and Sciences, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931 USA, E-mail: raman@mtu.edu Giovanni Macedonio, Osservatorio Vesuviano, Via Diocleziano, 328 Napoli,  Italy  I-80125, Tel: +39-081-6108-335, Fax: +39-081-6108-351, E-mail: macedon@osve.unina.it

NG01 Nonlinear Space-Time Patterns (Joint With A, B, G, OS, T)
Nonlinear space-time patterns occur in a variety of complex systems.  These space-time patterns represent the independent spatial modes of the system in terms of their associated temporal signal, and can provide significant scientific insight into both their sources and relative effects.  Examples of systems that exhibit space-time patterns include fault networks, mantle convection, the ocean-atmosphere interface, the human body, and solar activity.  Analysis of these patterns reveals information about the characteristics of the system in question.  Recent developments resulting in the relative inexpensive accessibility to computational power have greatly improved the ability to analyze these space-time patterns and have yielded a number of important scientific insights.  Applications include such widely varying fields as biometrics, seismic tomography, surface deformation, tidal signals, blood flow, and the El Nino-Southern Oscillation.  Abstracts that emphasize scientific results based on the analysis of space-time patterns are encouraged.  We plan to invite people and solicit contributions across a broad spectrum of sections at AGU.
Conveners: Kristy Tiampo, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Room 318, Boulder, CO 80309-0216 USA, Tel: +1-303-492-4779, Fax: +1-303-492-5070, E-mail: kristy@caldera.colorado.edu Andrea Donnellan, Mail Stop 126-347, Jet Propulsion Laboratory and University of Southern California, 4800 Oak Grove Dr., Pasadena, CA  91109 USA, Tel: +1-818-354-4737, Fax: +1-818-393-4965, E-mail: andrea.donnellan@jpl.nasa.gov

NG02 Geocomplexity: Self-Organizing Systems (Joint With A, GP, OS, S, T)
Self-organizing complex systems are found in many branches of geophysics.  The broadest-based example is fluid turbulence.  Specific examples include the stochastic variability of climate and the variability of Earth’s magnetic field.  Other examples are landforms and seismicity.  These systems are generally chaotic, exhibit fractal (power-law) behavior, and may be examples of self-organized criticality.  The proposed session will include broad overviews of the current understanding of complex systems as well as more specific recent developments.  This session is intended as an overview of the current status of geocomplexity and will include several key invited speakers.  Although this is not planned as a Union session, we strongly encourage contributions across a broad spectrum of AGU sections.  Contributions that are applicable in more than one area are particularly welcome.
Conveners: Donald L. Turcotte, Department of Geological Sciences, Cornell University, Snee Hall, Ithaca, NY 14853 USA, Tel: +1-607-255-7282, Fax: +1-607-254-4780, E-mail: turcotte@geology.cornell.edu John B. Rundle, Colorado Center for Chaos and Complexity and Cooperative Institute Research in Environmental Sciences, University of Colorado, Boulder, CO 80309 USA, Tel: +1-303-492-5642, E-mail: rundle@terra.colorado.edu William Klein, Physics Department and Center for Computational Science, Boston University, 590 Commonwealth Ave., Boston, MA 02215 USA, Tel: +1-617-353-2188, E-mail: klein@buphyc.bu.edu

NG03 Scaling and the Extremes of Geophysical Fields (Joint With A, H, OS, S, T)
From earthquakes to floods, volcanic eruptions to magnetic storms and hurricanes, the extremes of geophysical fields are of prime importance.  However, they are still poorly understood, and time series are often too short to yield the clear-cut empirical evidence necessary to distinguish between different theoretical behaviors.  Of particular significance is the distinction between standard extreme value distributions and the nonclassical heavy tailed (algebraic) distributions generally associated with space-time scaling processes.  This session will be devoted to the most recent theoretical and empirical developments of scaling approaches to understand and to characterize the interrelation between strong nonlinearities over wide ranges of temporal and spatial scales and their consequences for the extremes.  Session topics will include recent empirical investigations; techniques to test for the algebraic fall-offs in probability distributions; statistical estimators and data requirements; comparisons of mean and extreme instabilities/events; the statistics and dynamics of the extremes; the relevance of the paradigm of self-organized criticality; cascades, multifractals, and heavy tails; and nonclassical return period statistics and their implications.
Conveners: Daniel Schertzer, Laboratoire de Modelisation en Mecanique, Centre National de la Reserche Scientifique UMR 7607, Case 162, Université P. et M. Curie, 4 Place Jussieu, F-75252 Paris Cedex 05, France, Tel: +33-1-44-27-4963, Fax: +33-1-44-27-5259, E-mail: schertze@ccr.jussieu.fr Shaun M. Lovejoy, Physics Department, McGill University, 3600 University Str., Montreal, QC H3A 2T8, Canada, Tel: +1-514-398-6537, Fax: +1-514-398-8434, E-mail: lovejoy@physics.mcgill.ca Per Bak, Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen Ø, Denmark, Tel: +45-353-25393, Fax: +45-353-25016, E-mail: bak@nbi.dk Didier Sornette, Institute of Geophysics and Planetary Physics and Department of Earth and Space Science, University of California, 3845 Slichter Hall, Box 951567, 595 E. Circle Dr., University of California, Los Angeles, CA 90095 USA, Tel: +1-310-825-2863, Fax: +1-310-206-3051, E-mail: sornette@moho.ess.ucla.edu

NG05 Fractals, Chaos, and Self-Organized Criticality in Natural and Human-Induced Hazards (Joint With A, H, OS, S, T, V)
Natural and human-induced hazards cover a wide range of spatial and temporal scales.  They include a large variety and number of interacting components that combine to produce nonlinear power-law behaviors that are often associated with the basic concepts of complexity.  Examples of these hazards include floods, landslides, volcanic eruptions, earthquakes, forest fires, cyclonic storms, droughts, global warming, and hazardous waste contamination.  Papers that apply the concepts of fractals, chaos, or self-organized criticality to characterize, model, and assess the risk of natural and man-made hazards are solicited. Posters are also very much encouraged.
Conveners: Bruce D. Malamud, Department of Geography, Kings College London, Strand, London WC2R 2LS, UK, E-mail: bruce@malamud.com Didier Sornette, Institute of Geophysics and Planetary Physics and Department of Earth and Space Science, University of California, 3845 Slichter Hall, Box 951567, 595 E. Circle Dr., Los Angeles, CA 90095 USA, Tel: +1-310-825-2863, Fax: +1-310-206-3051, E-mail: sornette@moho.ess.ucla.edu Christopher Barton, U. S. Geological Survey, 600 4th St. South, St. Petersburg, FL 33701 USA, Tel: +1-727-803-8747 ext. 3014, Fax: +1-727-803-2030, E-mail:  barton@usgs.gov

NG06 Quantifying Predictability in Geophysical Systems II (Joint With A, G, H, OS, SH, T, V)
Our ability to quantify the predictability of nonlinear geophysical systems provides a fundamental bridge between models of geophysical systems and the systems themselves.  Uncertainty in the initial condition and errors in model formulation have led to probability forecasts (ensembles) even in deterministic systems.  This session will focus on atmospheric and ocean dynamics over hours to centuries (e.g., adaptive observation strategies, Lagrangian and Eulerian approaches, intense short-duration events); theoretical aspects of the dynamics of nonlinear systems relevant to predictability and verification (including multiple models, contrasting modeling strategies, data assimilation); and practical issues in the interpretation and likely economic impact of probabilistic forecasts on a timescale minutes to hours (e.g., precipitation/wind), days to months (e.g., hurricanes), and years to millennia (e.g., earthquakes).  A mix of oral and poster presentations of both pure and extremely applied contributions are welcome, and may focus on the predictability of geophysical systems other than those noted explicitly above.
Conveners: Leonard Smith, Oxford University, 24-29 St Giles', Oxford, OX1 3LB, UK, Tel: +44-1865-270-517, Fax: +44-1865-270-515, E-mail: lenny@maths.ox.ac.uk James Hansen, Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Room 54-1721, Cambridge, MA 02139 USA, Tel: +1-617-253-5935, E-mail: jhansen@mit.edu

NG07 Scaling, Multifractals, and Upscaling and Downscaling Techniques in Precipitation and Hydrology (Joint With A, H)
Hydrological processes are highly nonlinear over wide ranges of temporal and spatial scales.  Fractal structures and multifractal statistics are ubiquitous.  The corresponding scaling properties quantitatively relate statistics and structures at potentially widely different space-time scales and provide a systematic basis for aggregation (upscaling) and disaggregation (downscaling) techniques.  In addition, wide-range scaling can be used for space-time hydrological and precipitation modeling, determining intensity-duration relations, and areal reduction factors.  In the past several years, there have been many developments of specific techniques in order to handle these nonclassical scaling behaviors that are at best only poorly handled by conventional analysis and models.  This session will be devoted to the most recent theoretical and operational developments and applications of scaling and other innovative approaches to characterizing and modeling of (1) precipitation, in situ (e.g., rain gage) and remotely sensed (e.g. radar) rainfall measurements, nowcasting and multifractal techniques, and extreme precipitation, including the relationship of precipitation with other intermittent atmospheric processes; (2) surface processes, including run-off, river flows, river networks. flooding and their relationship with scaling topography; and (3) groundwater and subsurface processes, in particular transport and dispersion in scaling and hierarchical porous media.
Conveners: Shaun M. Lovejoy, Physics Department, McGill University, 3600 University Str., Montreal, QC H3A 2T8, Canada, Tel.: +1-514-398-6537, Fax: +1-514-398-8434, E-mail: lovejoy@physics.mcgill.ca Daniel Schertzer, Laboratoire de Modelisation en Mecanique, Centre National de la Reserche Scientifique, UMR 7607, Case 162, Université P. et M. Curie, 4 Place Jussieu, F-75252 Paris Cedex 05, France, Tel: +33-1-44-27-4963, Fax: +33-1-44-27-5259, E-mail: schertze@ccr.jussieu.fr  John Selker, Department of Bioresource Engineering, Gilmore Hall, Room 240, Corvallis, OR 97331-3906 USA, Tel: +1-541-737-6304, Fax: +1-541-737-2082, E-mail: selkerj@engr.orst.edu

NG10 Visual Computing in Nonlinear Geophysical Phenomena (Joint With A, G, GP, H, OS, T)
Researchers in geophysics are being overwhelmed by the huge amount of data generated by natural nonlinear phenomena and high-resolution numerical solutions.  In this session we will bring together many of the different practioners using modern analytical and visualization tools (e.g., wavelets, eigenvectors, and EOFs) for treating and analyzing large data sets.  We are soliciting examples from all areas in geophysics and at all scales, ranging from the molecular level, such as bacteria growth, to core dynamics.  Also of great interest are examples from large data sets, such as SAR, ocean currents, and numerical simulations involving the bridging of scales in nonlinear processes.  We foresee interest for this session from both numerical modelers and observation-oriented scientists.
Conveners: Dave Yuen, Minnesota Supercomputer Institute, 1200 Washington Ave., S., Minneapolis, MN 55415 USA, Tel: +1-612-624-1868, E-mail: davey@krissy.msi.umn.edu Bryan J. Travis, Los Alamos National Laboratory, ESS 5, MS F665, Los Alamos, NM 55455 USA, Tel: +1-505-667-1254, E-mail: bjt@vega.lanl.gov

NG11 Anomalous Transport in Inhomogeneous and (Multi-)Fractal Geophysical Media (Joint With A, H, OS, T)
Anomalous transport is ubiquitous in geophysics: mantle convection, subsurface hydrology, atmospheric and oceanographic diffusion, geophysical turbulence, solar wind, etc.  It is associated with nonstandard scaling (e.g., non-Fickian diffusion), and has been attracting a renewed interest owing to its importance for environmental applications, a larger availability of data, and several recently proposed theoretical approaches: fractal modeling, continuous time random walks, chaotic advection, fractional transport equations, multifractal dispersion coefficients, and multifractal advection equations.  This session will focus on the confrontation between the new available data and the new theoretical developments on anomalous transport in scaling and inhomogeneous geophysical media.
Conveners: Ioulia Tchiguirinskaia, Environmental Engineering and Science Department, Clemson University, 342 Computer Ct., Anderson, SC 29625 USA, Tel: +1-864-656-1462, Fax: +1-864-656-0672, E-mail: iouliat@clemson.edu Brian Berkowitz, Deparment of Environmental Sciences and Energy Research, Weizmann Institute of Science, PO Box 26, Rehovot, 76100, Israel, Tel: +972-8-934-2098, Fax: +972-8-934-4124,E-mail: brian.berkowitz@weizmann.ac.il Jeffrey Duan, Deparment of Applied Mathematics, Illinois Institute of Technology, 10 W. 32nd St., Chicago, IL 60616 USA, Tel: +1-312-655-3282, Fax: +1-312-567-3135, E-mail: duan@iit.edu
 

Biogeosciences (B)

B01 Remote Detection and Survey in Astrobiology and the Study of Life in Extreme Environments (Joint With P)
The distribution of life in extreme environments on Earth is commonly “patchy,” that is sporadic in space (on decimeter to kilometer scales ) and time, because local fluctuations in conditions fragment niches at the edges of habitability. Patchiness may also occur in prospective extraterrestrial habitats. Because sampling in a patchy environment entails risk of choosing poorly, information from a remote detection method can be valuable to focus sampling on promising locations and can provide information that affects the interpretation of data. Within our solar system, such reconnaissance may include searches for habitat (e.g., liquid water using radar or seismic sounding), for evidence of metabolism (e.g., atmospheric trace gas combinations far from chemical equilibrium), or for biochemical structure or molecules indicative of living material (e.g., fluorescence or Raman scattering observations of specific molecules). This session will focus on examples of remote methods for LExEn and astrobiological studies, on insights gained from such methods, and on physical interactions on which new methods may be based.  Abstracts are solicited from all relevant fields.
Conveners: Dale P. Winebrenner, Applied Physics Laboratory, University of Washington, Box 355640,
Seattle, WA 98195 USA, Tel: +1-206-543-1393, Fax: +1-206-616-3142, E-mail: dpw@apl.washington.edu

B02 Microbial Processes, I, Microbial-Mineral Interactions in Deep Subsurface Environments (Joint With P)
The continued discovery of intraterrestrial microorganisms necessitates the development of new methodology to investigate the impact of microbial-mineral interactions on the terrestrial deep subsurface.  This session will focus on recent research exploring the organic-inorganic biogeochemistry of the microbial-mineral interface within deep subsurface rock environments.  Interdisciplinary abstracts are solicited from all fields involving microbiology and earth sciences.  Relevant topics include, but are not limited to, biologically controlled or induced mineralization, bacterial-mineral precipitation, geochemical reactions and bioavailability, spatial relationships between biofilms and minerals, molecular geomicrobiology, microfossil detection, and possible exobiologic analogs.
Conveners:  Mary E. Kauffman, Idaho National Engineering and Environmental Laboratory, PO Box 1625, Idaho Falls, ID 83415 USA, Tel: +1- 208-526-2684, E-mail: kaufme@inel.gov
F. Grant Ferris, Department of Geology, Earth Sciences Center, University of Toronto, 22 Russell St., Toronto, ON M5S 3B1, Canada, Tel: +1-416-978-0526, E-mail: ferris@quartz.geology.utoronto.ca

B03 Microbial Processes, II, Constraints on Microbial Survival in Geological Environments (Joint With P)
Microorganisms are distributed in subsurface environments that range from those harboring multicellular and unicellular organisms to those in which extreme conditions allow only for unicellular life.  These conditions include low and high temperatures, hydrostatic and hyperbaric pressures, alkaline and acidic pH, oligotrophic chemical systems, tiny pore sizes, low moisture, an overabundance of microbial wastes, and niche environments where microbes depend on unusual physicochemical conditions to survive.
Each microbial environment limits the activity of its inhabitants through some combination of physical and chemical parameters.  Descriptions of microbial function in terms of thermodynamic variables, such as free energy, are increasingly common.  This session invites papers that explore the physical, chemical, and geologic conditions where subsurface organisms are found, particularly with reference to factors acting as limiting bounds on microbial activity. These papers may include descriptions of microbial communities, their numbers, diversity, or activity.  Thermodynamic descriptions of community limitations are especially encouraged.
Conveners:  Frederick Colwell, Biotechnology Department, Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID 83415, USA, Tel: +1-208-526-0097, Fax: +1-208-526-0828, E-mail: fxc@inel.gov; James McKinley, Pacific Northwest National Laboratory, Richland, WA 99352 USA, Tel: +1-509-375-6841, Fax: +1-509-375-6954, E-mail: james.mckinley@pnl.gov

B04 Halocarbons: Global Biogeochemistry and Contaminant Transformations (Joint With A, OS)
This special session will broadly cover topics in halocarbon research including sources and sinks of halogenated compounds in oceanic, freshwater and terrestrial environments, biogeochemistry of trace atmospheric halocarbons, and transformations of halogenated contaminants. Abstracts are solicited from all disciplines involved in the study of abiotic or biological processes that influence the fate of  halocarbons. Suggested topics include rates and mechanisms of production/consumption in pristine or impacted environments, degradation studies including flowpath modeling, isotopic investigations of source/sink signatures, and examination of processes that control the distribution of halocarbons in the atmosphere.
Conveners: Larry Miller, U.S. Geological Survey, MS 465, 345 Middlefield Rd., Menlo Park, CA  94025 USA, E-mail: lgmiller@usgs.gov Kelly Goodwin, Tel: +1-650-329-4475, Fax: +1-650-329-4327,
E-mail: goodwin@aoml.noaa.gov

B05 The Influence of Hydrosphere-Biosphere Interactions on the Speciation and Transport of Metals in Surface Waters (Joint With H)
The interplay between transport and reaction processes determines the fate of many metal contaminants in aquatic systems. In most instances, chemical reactions are driven/catalyzed by biological systems that in
turn influence the reactivity and speciation of contaminants. In addition, flow regimes exert selective pressures for the establishment of various biotopes. This session will examine how the interplay
between hydrologic and biogeochemical processes controls the reactivity, mobility, transport, and fate of metals in surface waters, and how these processes affect biological systems. We especially encourage
presentations that examine the interdisciplinary nature of these processes, such as the analysis of feedback mechanisms involving the uptake of metals by biota, biotic control of metal speciation, and the mobility of metals in aquatic systems.
Conveners: Jean-Francois Gaillard, Department of Civil Engineering, Northwestern University, 2145   Sheridan Rd., Evanston, IL 60208-3109 USA, Tel: +1-847-467-1376, Fax: +1-847-491-4011, E-mail:
jf-gaillard@northwestern.edu Aaron Packman, Department of Civil and Architectural Engineering, Drexel University, Philadelphia, PA 19104 USA, Tel: +1-215-895-2087, Fax: +1-215-895-1363, E-mail:  pack@drexel.edu

B06 Nitrogen-Cycling Processes in Rivers and Streams (Joint With H)
Delivery of nitrogen to coastal waters by rivers and streams is a topic of growing national and international concern.  A major aspect of N-loading to coastal environments is the net effect of in-stream processes during transport. Much remains unknown about nitrogen-cycling processes within rivers of any scale, or how these processes interact with the hydrologic cycle and other biogeochemical cycles to affect nitrogen transport.  This session will focus on in-stream nitrogen-cycling processes, particularly nitrification and denitrification, and quantitative field studies to assess their impact.  Presentations are encouraged that describe factors controlling nitrogen transformation; the extent to which geochemical signals, such as stable isotope ratios and trace constituents (e.g., nitrite and nitrous oxide), can be used to characterize nitrogen-cycling processes; and studies comparing methodologies for assessing these processes in situ.
Conveners:  Richard L. Smith, U.S. Geological Survey, 3215 Marine St., Boulder, CO 80303 USA, Tel: +1-303-541-3032, Fax: +1-303-447-2505, E-mail: rlsmith@usgs.gov and Frank J. Triska, U. S. Geological Survey, 345 Middlefield Rd., Mail Stop 439, Menlo Park, CA 94025 USA, Tel: +1-650-329-4437, Fax: +1-650-329-4463, E-mail: fjtriska@usgs.gov

B07 Life in a Turbulent Environment: Primary Production in the Surface Mixed Layer (Joint With OS)
Turbulence impacts upon aquatic ecology over a wide range of spatial and temporal scales. Within the  surface mixed layer, large-scale turbulence maintains near-uniform distributions of temperature,
salinity, nutrients, etc. while small-scale turbulence (or shear flows) reduces the thickness of diffusive boundary layers and impacts upon nutrient uptake, particle encounter frequencies, and motile organisms' abilities to maintain a preferred orientation. As well, the thickness of the surface mixed layer responds to changes in the input of turbulent kinetic energy and this in turn modifies the irradiance experienced by primary producers circulating with in the mixed layer. Contributions are sought regarding the responses of phyto- and zooplankton to environmental turbulence. Reports of interdisciplinary field studies are particularly encouraged. A partial list of topics includes photophysiological responses to changes in irradiance caused by fluctuations in turbulence intensity and/or mixed layer depth; modeling photosynthesis in a turbulent environment; the impact of turbulence on the migration or swimming
behavior of buoyant and motile species; and the impact of small-scale turbulence on nutrient uptake, particle flocculation, and predator-prey interactions.
Convener:  Bradford Sherman, Aquatic Systems Modelling Group, CSIRO Land and Water, GPO Box 1666, Canberra, ACT 2601, Australia, Tel: +61-2-6246-5579, Fax: +61-2-6246-5560, E-mail:  Brad.Sherman@cbr.clw.csiro.au

B08 New Breakthroughs in Field-Scale Bacterial Transport (Joint With H)
Microbial transport in the presence of subsurface physical and chemical heterogeneities is poorly understood due to the limited number of successful field experiments.  This lack of understanding hinders the design of bioaugmentation strategies, the modeling of pathogen contamination in the groundwater, and assessment of the hydrodynamic impact of introduced organisms to the subsurface microbial communities. In this session new and innovative field-scale bacterial transport approaches and results will be presented and discussed. This session will highlight results of a field-scale bacterial transport experiment conducted near the town of Oyster, Virginia, including the design optimization of microbial strains, tracer test experimental parameters and instrumentation, multiscale hydrogeological characterization, novel methods for tracking bacteria, the effects of physical and chemical heterogeneity on field-scale bacterial transport, quantification of microbial transport processes for modeling, variations in microbial ecology associated with the experiment, and the effects of predation on bacterial transport. This session should be of interest to a broad audience interested in bioaugmentation strategies for bioremediation, and participation by all researchers working on these issues is encouraged.
Conveners: Susan Hubbard, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., MS 90-1116, Berkeley, CA 94720 USA, Tel: +1- 510-486-5266, E-Mail; sshubbard@lbl.gov: Brian Mailloux, Department of Geosciences, Princeton University, 114 Guyot Hall, Princeton, NJ 08544 USA, Tel: +1-609-258-1622, E-mail: mailloux@geo.princeton.edu Tim Scheibe, Pacific Northwest National Laboratory, PO Box 999, MSIN K9-36, 902 Battelle Blvd., Richland, WA 99352 USA,  Tel: +1-509-372-6065 E-mail: tim.scheibe@pnl.gov

B09 The Role of Fire in the Boreal Forest and Its Impacts on Climatic Processes (Joint With A, NG)
Boreal forests account for about a third of the carbon sequestered in terrestrial ecosystems, so changes in their functioning or distribution could create important feedbacks to the climate system. Changes in the extent of forest cover could alter regional energy budgets sufficiently to amplify or nullify the expected rapid climatic warming at high latitudes. Warming could cause boreal forests to change from being a component of the "missing sink" of carbon dioxide to being a net source if fire frequency or decomposition increases. The rate of change in boreal forests is governed by fire frequency and severity, with important effects on carbon and energy flows. In the boreal forests several feedback mechanisms must be quantified to fully understand the role of fire in influencing landscape response to a changing climate. Some topics that this session will address are (1) changes in carbon stocks caused by immediate off-site transfer during the fire and by changes in decomposition and production following fire; (2) changes in energy budgets caused by fire; and (3) changes in the structure of the ecosystem, with associated changes in carbon or energy budgets.
Conveners: Larry Hinzman, Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK 99775-5860 USA, Tel: +1-907-474-7331, Fax: +1-907-474-7979, E-mail: ffldh@uaf.edu   F. Stuart Chapin, Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775 USA, Tel: +1- 907-474-7922, Fax: +1-907-474-6716, E-mail: fschapin@bonanza.lter.uaf.edu

B10 Land-Atmosphere Interactions, I, Arctic Transitions (Joint With A, H)
This session will focus on spatial and temporal patterns and controls over land-atmosphere surface exchange of mass and energy in arctic tundra and in transition regions between arctic tundra and boreal forest. High-latitude ecosystems play an important role in the functioning of the earth system because they occupy a large area; are sensitive to changes in climate; influence the exchanges of water, energy, and radiatively active gases with the atmosphere; and affect regional and global climate.  Functional responses of arctic tundra to climate variability and change have the potential to influence global climate through the exchange of radiatively active gases with the atmosphere. Spatial variation in vegetation within arctic tundra has substantial climatic effects that extend beyond tundra. Structural responses, which include treeline changes and vegetation changes associated with fire, may substantially alter water and energy exchange in transitional regions of arctic and boreal vegetation to influence regional climate. Abstracts are solicited on relationships among vegetation, soils, permafrost, snow, and climate in arctic regions that have implications for regional and global climate.
Conveners: A. David McGuire, Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775 USA, Tel: +1-907-474-6242, Fax: +1-907-474-6716, E-mail: ffadm@uaf.edu Matthew Sturm, U.S. Army Cold Regions Research and Engineering Laboratory, PO Box 35170, Ft. Wainwright, AK 99703-0170 USA, Tel: +1-907-353-5183, Fax: +1-907-353-5142, E-mail: msturm@crrel41.crrel.usace.army.mil

B11 Land-Atmosphere Interactions, II, North Africa (Joint With A, H)
This session focuses on the interactions between the atmosphere and the terrestrial biosphere over north Africa as well as change and variability of the coupled biosphere-atmosphere-ocean system. Relevant  topics include, but are not limited to, the natural coevolution of the biosphere-atmosphere system; the  influence of the ocean, in particular sea surface temperatures and their variability, on the biosphere-atmosphere interaction; the role of the terrestrial biosphere in both the modern climate and the paleoclimate; reconstruction of paleoclimate; impact of anthropogenic land cover changes.
Conveners: Guiling Wang, Princeton Environmental Institute, 27 Guyot Hall, Princeton University, Princeton, NJ 08544-1003 USA, Tel: +1-609-258-3511, E-mail: gwang@princeton.edu Martin Claussen, Potsdam Institute for Climate Impact Research, PO Box 601203, 14412 Potsdam, Germany, Tel: +49-331-288-2522, Fax: +49-331-288-2600, E-mail: claussen@pik-potsdam.de

B12 Responses of Soil Processes to Elevated Atmospheric CO2 (Joint With A)
Research on the responses of ecosystems to elevated atmospheric CO2 has resulted in a wealth of information. While some consensus can be found regarding aboveground responses to elevated atmospheric CO2, many questions remain on the magnitude, and even the direction of changes in soil carbon and nutrient cycling and soil microbial feedbacks. Understanding the response of soil processes to
elevated CO2 is important, because these processes can strongly influence both the short-term and long-term responses of ecosystems to elevated CO2. Soil processes are difficult to observe, and the variety of measurement techniques often complicates direct comparison of results. Recent studies on understanding responses of belowground processes to elevated atmospheric CO2 are the subject of this session. Some of the important topics that may be addressed include (1) soil microbial feedbacks and microbial biomass turnover; (2) carbon and nutrient cycling and availability, including 15N and 13C isotopic tracer studies; (3) litter decomposition and SOM turnover; (4) changes in soil biology; and (5) trace gas fluxes.
Conveners: Jennifer King, USDA Agricultural Research Service, PO Box E, Fort Collins, CO, 80522 USA, Tel: +1-970-490-8255, Fax: +1-970-490-8213, E-mail: jyking@lamar.colostate.edu Bruce Hungate, Department of Biological Sciences, Northern Arizona University, Box 5640, Flagstaff AZ 86011-5640 USA, Tel: +1-520-523-0925, Fax: +1-520-523-7500, E-mail: bruce.hungate@nau.edu Arvin Mosier, USDA-Agricultural Research Service, PO Box E, Fort Collins, CO 80522 USA, Tel: +1-970-490-8250, Fax: +1-970-490-8213, E-mail: amosier@lamar.colostate.edu

B13 Ecological Component of Large Scale Biosphere-Atmosphere Experiment (LBA) (Joint With A)
This session deals with studies related to the question "How do tropical forest conversion, regrowth, and selective logging influence carbon storage, nutrient dynamics, trace gas fluxes, and the prospect for sustainable land use in the Amazon region?" “Forest conversion” refers to forest clearing and conversion to agricultural uses, especially cattle pasture, and "forest regrowth" refers to forest growth following the abandonment of agricultural lands.  The ecological component of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) includes studies of the effects of these land cover and land use changes on terrestrial carbon and nutrient budgets, the fluxes, of trace gases between the land and the atmosphere, and the exchange of materials between the land and river systems.  Implicitly, the understanding effects of land use changes requires an understanding of these budgets, fluxes and exchanges in "primary" or predisturbance forest ecosystems.
Convener: Michael Keller, LBA-Ecology, Complex Systems Research Center, University of New Hampshire, Durham, NH  03824 USA, Tel  +1-603-862-4193, Fax  +1-603-862-0188, E-mail: lba.ecology@unh.edu

B14 Land Use Change, I, A Paleoenvironmental Perspective on Ecosystem Sustainability (Joint With A)
During the last two millennia, virtually all ecosystems, both managed and quasi-natural, have been subjected to greater fluctuations of climate than are captured by instrumental records. Over the same time span, human impacts on ecosystems have varied and, in many cases, increased dramatically. Documenting, understanding, and distinguishing the role of both types of processes, and the interactions between them, in generating contemporary ecosystems are vital for developing any realistic sense of future sustainability. Case studies from specific ecosystems and regions, as well as model simulations of ecosystem responses, are required. The session will seek to (1) present case studies illustrating the value of paleoecological studies in understanding ecosystem responses to climate change and human impacts; (2) demonstrate appropriate and effective uses of paleoecological data in ecosystem management, conservation, and restoration; and (3) foster development of a robust research and applied framework for maximizing the contribution of paleoecological information to understanding and enhancing future sustainability.
Conveners:  Frank Oldfield, PAGES International Project Office, Barenplatz 2,CH-3011 Bern, Switzerland, Tel: +41-31-312-3133, Fax: +41-31-312-3168, E-mail:  frank.oldfield@pages.unibe.ch  Constance Millar, USDA Forest Service, PSW Research Station, 800 Buchanan St., Albany, CA 94710 USA, Tel: +1-510-559-6435, Fax: +1-510-559-6499, E-mail: cmillar@fs.fed.us

B15 Land Use Change, II, Global Land Use and Land Cover Change Over the Last 300 Years (Joint With A)
Past changes in land use and land cover have impacted climate at regional to continental scale, significantly modified atmospheric carbon concentrations, and created much of the landscape upon which future global change will act. It is therefore becoming increasingly urgent to characterize and quantify these changes, especially for the last 300 years, using all the methods available, ranging from pollen analysis to documentary evidence. The session will summarize recent progress in reconstructing the history of recent land use and cover change resulting from the International Geosphere-Biosphere Programme’s PAGES/LUCC BIOME 300 and other initiatives, and outline the major consequences of the results obtained so far.
Convener:  Frank Oldfield, PAGES International Project Office, Barenplatz 2, CH-3011 Bern, Switzerland, Tel: +41-31-312-3133, Fax: +41-31-312-3168, E-mail: frank.oldfield@pages.unibe.ch Rik Leemans, National Institute of Public Health and Environment, Bureau of Environment and Natural Resources, Antonie van Leewenhoeklaan 9, PO Box 1, NL-3720 BA Bilthoven, Netherlands, Tel: +31-30-274-3377, Fax: +31-30-885-7357, E-mail: rik.leemans@rivm.nl
 

B16 Biospheric Results from Terra, NASA’s Earth Observing System (Joint With A, H, OS)
The launch of National Aeronautics and Space Administration's Earth Observing System (EOS) Terra on December 18, 1999, marked a new phase of climate and global change research, especially for increased understanding of the interaction of the land and ocean biology with climate.  Terra has scientific instruments to gain information about the Earth's land, oceans, and atmospheres with unprecedented accuracy. Of the five scientific instruments, three are germane to land and ocean remote sensing: the Moderate Resolution Imaging Spectroradiometer (MODIS), the Multiangle Imaging Spectroradiometer  (MISR), and the Advanced Spaceborne Thermal Emission and Reflection Radiometer  (ASTER). This session would focus on results of biospheric research utilizing the Terra spacecraft. Invited papers will be concerned with results of using Terra instruments (MODIS, MISR, and ASTER) for land cover and change, vegetation attributes such as leaf area index and absorptance of photosynthetically radiation, and links into ecosystem models. Recent work by the oceans community regarding chlorophyll and productivity will also be solicited to make the session representative of Terra's biospheric science research.
Convener:  Jon Ranson, Biospheric Sciences Branch, NASA Goddard Space Flight Center, Code 923, Greenbelt, MD 20771 USA, Tel: +1-301-614-6650, Fax: +1-301-614-6695, E-mail: jon.ranson@gsfc.nasa

B17 The Science of Carbon Sequestration (Joint With OS, V)
Several complementary strategies have been proposed to limit the accumulation of anthropogenic carbon dioxide in the atmosphere. It has been proposed that carbon dioxide generated during fossil fuel burning (or as a result of land use changes) could be stored in the terrestrial biosphere, the oceans, or deep geologic reservoirs, effectively sequestering this carbon dioxide away from the atmosphere. The U. S. Department of Energy has set up centers to study these issues in collaboration with the broader community; CSITE for studying terrestrial biosphere options; DOCS for studying ocean sequestration options; and GEO-SEQ for studying geologic sequestration options. Presentations are requested focusing on scientific results that are critical to understanding, evaluating, and addressing issues relevant to proposed carbon sequestration strategies, including research gaps, effectiveness, unintended impacts, and feasibility and cost.
Conveners: Jeff Amthor, CSITE, Oak Ridge National Laboratory, MS 6422, PO Box 2008, Oak Ridge, TN 37831-6422 USA, Tel: +1-865-576-2779, Fax: +1-865-576-9939, E-mail: amthorjs@ornl.gov Sallie Benson, GEO-SEQ, Lawrence Berkeley National Laboratory, MS 90-1116, Berkeley, CA 94720 USA, E-mail: smbenson@lbl.gov Jim Bishop, DOCS, Lawrence Berkeley National Laboratory, MS 90-1116, Berkeley, CA 94720 USA, Tel: +1-510-495-2457, Fax: +1-510-486-5686, E-mail: jkbishop@lbl.gov  Ken Caldeira, DOCS, Lawrence Berkeley National Laboratory, 7000 East Ave., L-103, Livermore, CA 94550 USA, Tel: +1-925-423-4191, Fax: +1-925-422-6388, E-mail: kenc@llnl.gov

B18 Biogeosciences: Expanding Horizons in Understanding Earth and Planetary Systems
This special session is planned as a showcase for the new Biogeosciences section of AGU, both to provide an overview and to illustrate the many ways that biogeosciences relates to existing AGU disciplines. The new Biogeosciences section was formed to promote the broadest possible understanding of geophysical sciences, especially the interaction of biological and geophysical processes in controlling the Earth and planetary systems. This session highlights exciting research ongoing in the areas of biogeochemistry, biogeophysics, global ecosystems, astrobiology, and evolutionary geobiology, as well as their bearing on the more "traditional" geophysical sciences. The session will include a few key invited speakers, and a major poster session for which abstracts are solicited in any of the fields of biogeosciences. The session will be followed by a reception hosted by the new Biogeosciences section of AGU.
Conveners: Dork Sahagian, IGBP/GAIM, Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824 USA, Tel: +1-603-862-3875, Fax: +1-603-962 3874, E-mail: gaim@unh.edu Joe Kirschvink, Division of Geological & Planetary Sciences, California Institute of Technology, 1200 E. California Blvd., MS 170-25, Pasadena, CA 91125 USA, Tel: +1-626-395-6136, Fax: +1-626-568-0935, E-mail: kirschvink@caltech.edu

B19 Iron Cycling in the Natural Environment: Biogeochemistry, Microbial Diversity, and Bioremediation
Microorganisms that reduce Fe(III) or oxidize Fe(II) play important roles in the cycling of C, H, and Fe in low temperature
sedimentary environments. They are also the primary players in metal or organic carbon contaminated soils and groundwaters.
Furthermore, iron oxidation and reduction may be among the first respiratory processes in the evolution of microbial metabolism.
This session will focus on the current knowledge of iron biogeochemistry, diversity and physiology of iron-reducing and
iron-oxidizing microorganisms, and new applications for quantifying their roles in biogeochemical processes in natural systems.
Relevant topics will include but are not limited to:
Biogeochemical iron cycling in natural environments, species and metabolic pathways of iron-reducing and iron-oxidizing bacteria,
stable isotopes (C, O, and Fe) and other biomarkers associated with microbial iron reduction, mechanisms of iron biomineralization,
effect of microbial interactions on iron cycling in natural environments, bioremediation of metal and organic contaminated aquifers,
and iron reduction by extremophiles.
Conveners: Chuanlun Zhang, Department of Geological Sciences, University of Missouri, 101 Geological Sciences Bldg., Columbia, MO 65211 USA, Tel: +1-573-884-2677, Fax: +1-573-882-5458, E-mail: zhangCL@missouri.edu John Coates, Microbiology, Southern Illinois University, Mailcode: 6508, Carbondale, IL 62901 USA, Tel: +1-618-453-6132, E-mail: jcoates@micro.siu.edu

B20 Phosphate Cycling in the Marine and Terrestrial Environments (Joint with OS)
Phosphate is an essential nutrient for organisms at all levels of the food chain both in the terrestrial and marine environments and often it is a limiting nutrient.  This session will focus on all aspects of the P cycle in the present and past.  Characterization of P pools in seawater and soil, methods to estimate P recycling rates, P sources to different ecosystems, changes in P fluxes with
time and space, estuaries and lake eutrophication due to P pollution, new methods and models or quantifying processes involved in the P cycle and other P related topics will be covered.  This is a joint ocean and biogeochemistry session.
Conveners:  Dr. Adina Paytan, Department of Geological and Environmental Sciences, Stanford University, Stanford CA 94305-2115;  Tel: +1-650-724-4073; Fax: +1-650-725-0979; E-mail: apaytan@pangea.stanford.edu:  Dr. Barbara Cade-Menun, Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 Tel: +1-650-725-0927;  Fax:  1+650-725-0979; E-mail:  bjcm@pangea.stanford.edu

A06 Investigation of Atmosphere-Earth Interactions With Cooperative Atmosphere-Surface Exchange Study 97 and 99 Data (Joint With B)
The main goal of the Cooperative Atmosphere Surface Exchange Study (CASES) is to investigate atmosphere-earth interactions in a mesoscale watershed through long-term observations. Two field
programs, CASES-97 and CASES-99, took place from April 21to June 17, 1997, and during the month of October 1999, respectively. These programs were conducted to study the role of land-surface processes in the diurnal evolution of the convective boundary layer and the nocturnal boundary layer. The
purpose of this session is to discuss the progress and determine issues that need to be addressed for further field experiments. This special session solicits papers on CASES data analysis,  development/validation of land-surface and boundary layer models, and application of CASES data in mesoscale and  general circulation models. Papers on similar topics are also encouraged.
Conveners: Margaret LeMone, Mesoscale and Microscale Meteorology, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307 USA, Tel: +1-303-497-8962, Fax: +1-303-497-8171, E-mail: lemone@ucar.edu Fei Chen, Research Applications Program, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307 USA, Tel: +1-303-497-8454, Fax: +1-303-497-8401, E-mail: feichen@ucar.edu and Jielun Sun, Mesoscale and Microscale Meteorology, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307 USA, Tel: +1-303-497-8994,
Fax: +1-303-497-8171, E-mail: jsun@ucar.edu

A11 NOAA Postdoctoral Program in Climate and Global Change  (Joint With B, OS)
The purpose of the program is to help create and train the next generation of researchers needed for  climate studies.  It was anticipated that several contemporary National Oceanic and Atmospheric Administration (NOAA) efforts, such as TOGA and its ambitious field programs (e.g., COARE), would undoubtedly generate a tremendous amount of data that would require the attention of an enlarged research community here and abroad.  In the larger view, it was necessary to attract some of the new Ph.D.’s to the community in order to establish the seeds of scientific leadership for the extended programs of the future.  Thus, the program endeavors to attract outstanding recent Ph.D.’s in the sciences relevant to the NOAA Climate and Global Change Program.  The program supports research on climate variations with timescales of seasons to centuries.  This is the 10th year of this very successful fellowship program.  We propose to mark the event by holding a half-day afternoon session at the AGU Fall Meeting with a reception immediately following a series of invited talks.  We envision that the afternoon would consist of the following: one 20 minute talk that summarizes the history and scope of the program, and nine invited talks (20 minutes each) from past and present participants in the program who gone on to become leaders in various disciplines. The topic of each talk will be influenced heavily by the speaker, so that each talk will be cutting-edge research, with many of the talks likely to be on "hot topics." (The talks are not to be a review of what the speaker did while he/she was a postodc in the program.) Both the reputations of the speakers and the topics should ensure that this will be a very well attended session.
Conveners: David Battisti, Department of Atmospheric Sciences, University of Washington, Box 351640
Seattle, WA  98195-1640 USA, Tel: +1-206-543-2019, Fax: +1-206-543-0308, E-mail: david@atmos.washington.edu Daniel P. Schrag, Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street Cambridge, MA  02138 USA, Tel: +1-617-495-7676, Fax: +1-617-496-4387, E-mail: schrag@eps.harvard.edu

H28 Hydrologic and Ecosystem Research and Applications in Long-Term Experimental Watersheds  (Joint With B)
This is a poster session designed to highlight the major research efforts and data sets that are available at experimental watersheds in the United States and overseas.  We solicit posters from a range of watersheds with long term monitoring including those from the Long Term Ecological Research network, USDA Agricultural Research Service watersheds, the U.S. Geological Survey Wetland Ecology Branch sites, and other U.S. and international sites.  Each poster should include information on the major research questions pursued and active research under way, an overview of the data sets that are available, as well as novel and current research findings and resulting applications.  The poster session will provide an opportunity for researchers to identify potential synergistic studies and intercomparisons, and familiarize the community with the research and data resources available.
Conveners: Danny Marks, Northwest Watershed Research Center, USDA Agricultural Research Service, 800 Park Blvd., Plaza IV, Suite 105, Boise, ID 83712 USA, Tel: +1-208-422-0700, E-mail: dmarks@nwrc.ars.pn.usbr.gov L. E. Band, Department of Geography, University of North Carolina, Chapel Hill, NC 27599 USA, Tel: +1-919-962-3921, E-mail: lband@email.unc.edu

H29 Coupled Hydrological and Terrestrial Ecosystem Processes (Joint With B)
Surface and near-surface hydrological and ecosystem processes are intimately coupled in watersheds.  An understanding of their interactions is necessary for improved assessment and modeling of water balance, carbon and nutrient cycling, canopy growth, and landscape change and succession.   Topics can include the development of distinct terrestrial ecosystem patterns as conditioned by soil water patterns and flowpaths in complex landscapes, the role of these patterns on water balance at the catchment scale, rates of carbon sequestration, and nutrient cycling along topo-edaphic gradients.  Topics on the sensitivity of these systems to changes in water balance due to shifts in climate or land cover change are also encouraged.  In addition, the session is intended to highlight studies investigating the links between terrestrial ecosystem and hydrological processes.  Abstracts are solicited that discuss measurement or modeling studies of ecosystem and hydrological interactions ranging from the plot to watershed scale.
Conveners:  D. Scott Mackay, Department of Forest Ecology and Management, University of Wisconsin, Madison, WI 53706 USA, Tel: +1-608-262-1669, E-mail: dsmackay@facstaff.wisc.edu Brent Newman, Earth and Environmental Sciences Division, Los Alamos National Laboratory, MS J495, Los Alamos, NM 87545 USA, Tel: +1-505-667-3021, E-mail: bnewman@lanl.gov Brad Wilcox, Inter-American Institute for Global Change Studies, A.Dos Astronauts 1758, 12227-010 Sáo José dos Campos, SP, Brazil, Tel: +55-12-345-6860, E-mail: bwilcox@dir.iai.int

H33 Dissolved Organic Matter in Surface Water and Groundwater:  Characterization, Production, Transport, and Fate (Joint With B)
Recent work suggests that hydrologic flow paths, microbial processes, soil mineralogy, and soil nutrient balance can all affect the concentration and flux of colloidal and dissolved organic matter (DOM) in surface water and groundwater.  In many cases physical, chemical, and biological processes are intimately linked, and their relationships may change over time.  Understanding this complex set of interactions is an ongoing challenge for biogeochemists.  Appropriate topics for this session would include physical and chemical control of DOM concentrations along flow paths; microbial production and consumption of DOM; measurement or prediction of DOM flux at local, regional, or biome scales; photodegradation of DOM; methods to characterize organic matter (fluorescence spectra, physical separations, and NMR); and links between cycling of DOM and dissolved organic nitrogen or other nutrients.  Papers are expected to include studies of DOM dynamics at different spatial scales, in a variety of terrestrial and aquatic environments.
Conveners: William H. McDowell, Department of Natural Resources, University of New Hampshire, 219 James Hall, Durham, NH 03824 USA, Tel: +1-603-862-2249, Fax: +1-603-862-4976, E-mail: bill.mcdowell@unh.edu Jacqueline A. Aitkenhead Peterson, Department of Natural Resources, University of New Hampshire, 215 James Bldg., Durham, NH 03824 USA, Tel: +1- 603-862-1020, Fax: +1-603-862-4976, E-mail: jaa@cisunix.unh.edu Elizabeth Boyer, College of Environmental Science and Forestry, State University of New York, 1 Forestry Dr., Syracuse, NY  13210 USA, Tel: +1-315-470-4818, E-mail:  boyer@syr.edu

OS06 Redox Processes in Oxygen Deficient Regions of the Ocean (Joint With A, B)
Recent research cruises to locations such as the Arabian Sea, the eastern tropical North Pacific, and the Cariaco Basin have heightened interest in redox processes occurring in oxygen-deficient regions of the ocean. In particular, these environments are sources of atmospheric greenhouse gases such as nitrous oxide, and their sedimentary records may contain valuable paleo-oceangraphic indicators. This session aims to provide a venue for a wide-ranging discussion of the biogeochemistry of these intriguing environments, their affect on global biogeochemical cycles, and the information that their sediments record.
Conveners: Frank Sansone, Oceanography Department, University of Hawaii, 1000 Pope Rd., Honolulu, HI  96822 USA, Tel: +1-808-956-8370, Fax: +1-808-956-7112, E-mail: sansone@soest.hawaii.edu Mary Scranton, Marine Sciences Research Center, State University of New York at Stony Brook, Stony Brook, NY 11794-5000 USA, Tel: +1-631-632-8735, E-mail: mscranton@notes.cc.sunysb.edu

OS07 Geosphere-Biosphere Coupling: Cold Seep Related Carbonate and Mound Formation and Ecology (Joint With B)
Carbonate mounds are prominent reef types during Earth history since Cambrian times. These mounds frequently form giant host rocks for hydrocarbon accumulation.   Recent discoveries of spectacular modern carbonate mounds along the United States, African, Asian, and European continental margin provide an outstanding opportunity to study the sedimentary processes of these buildups. Seepage of hydrocarbons may play a role, although a link with fluid expulsion from depth is still poorly understood. As present-day mound provinces occur at or near areas of increased exploration for hydrocarbons, there is an obvious need to better understand their occurrence, origin, and possible relationship to cold seepage or hydrocarbon leakage, as well as to establish their potential impact on seabed stability and relationship to external forcing mechanisms such as climatic change effects.
Conveners: W. C. Dullo, Geomar, Wischhofstrasse 1-3, D-24148 Kiel, Germany, Tel: +49-431-600-2215, Fax: +49-431-600-2925, E-mail: cdullo@geomar.de E. Suess, Geomar, Wischhofstrasse 1-3, D-24148 Kiel, Germany, Tel: +49-431-600-2215, Fax: +49-431-600-2925, E-mail: esuess@geomar.de P. Henriet, Renard Centre of Marine Geology, University of Ghent, Krijgslaan 281 S8, B-9000 Ghent, Belgium, Tel: +32-9-264-45-85, Fax: +32-9-264-49-67, E-mail: jeanpierre.henriet@rug.ac.be C. E. van Weering, Netherlands Institute for Sea Research, PO Box 59, Texel, Netherlands, Tel: +31-222-369395, Fax: +31-222-319674, E-mail: rhaas@nioz.nl William W. Sager, Department of Oceanography, Texas A&M University, College Station, TX 77843-3146 USA, Tel: +1-979-845-9828, Fax: +1-979-845-6331, E-mail: wsager@ocean.tamu.edu

OS22 Linking Climate Variability and Coastal Processes (Joint With B, H)
Climate variability, occurring across a range of time-scales, significantly impacts geologic, hydrologic, hydrodynamic, and biologic processes acting in the coastal zone. As climate varies in the future, changes in the intensity, frequency, and location of storms, distribution of rainfall, rate of sea level rise, and water temperature will drive changes in river discharge, nearshore sediment transport, shoreline erosion, and nutrient supply. This session seeks to explore such links between climate variability and coastal processes across a range of time-scales and disciplines as observed in the past and predicted for the future. Abstracts linking climatic and coastal processes are solicited from all relevant disciplines of the natural sciences. Abstracts exploring the societal impacts of changes in coastal processes driven by climate variability are also welcomed.
Conveners:  Laura J. Moore, Geology and Geophysics Department, Woods Hole Oceanographic Institution, MS 22, Woods Hole, MA 02543 USA, Tel: +1-508-289-3597, Fax: +1-508-457-2187, E-mail: lmoore@whoi.edu; Philip Mote, JISAO/SMA Climate Impacts Group, University of Washington, Box 354235, Seattle WA 98195 USA, Tel: +1-20