1996 AGU Spring Meeting Special Session Descriptions

Updated Feb 9 1996

Special session descriptions are located below. AGU places special session descriptions on the Web as they are received. Please check often.

If submitting an abstract to a special session, in addition to sending one original and two copies of your abstract with payment, to AGU by 5:00 p.m., EST, February 29, 1996, or by e-mail by 12:00 midnight, February 29, you must send a copy of your abstract by February 22, to the convener(s). Sending a copy of your abstract solely to a convener does not constitute sending it to AGU.

ALL abstracts must include payment information. If you wish to submit a paper to a special session, give the code and title of the session in the abstract submittal information. Papers on other topics not listed here are encouraged.

Union

U01 Geophysical Research and the Smithsonian Institution: 1846-1996 (AGU History Committee) (Joint with A, P, SH) (revised/updated version)

This is a special session on geophysics and the Smithsonian Institution on the occasion of the Smithsonian's 150th anniversary. Historical papers and reviews of current Smithsonian-related geophysical research are solicited. Examples of this research include 19th-century weather and climate networks, solar research under Secretaries Langley and Abbot, international distribution of meteorite collections, and historical or contemporary work at the Smithsonian Astrophysical Observatory.

Convener: James R. Fleming, Science and Technology Studies, Colby College, Waterville, ME 04901, tel: 207-872-3548, fax: 207-872-3074, e-mail: jrflemin@colby.edu

U02 Earth System Dynamics From High Frequency to Global Change Timescales (Joint with A, G, O)

Components of the Earth system exchange momentum and mass on multiple timescales, and so important couplings exist for a variety of geophysical processes. For one such process, changes in atmospheric angular momentum due to winds and mass distribution are linked to those of Earth's rotation, with the oceans playing an additional role due to variations of currents, mass redistribution, and sea level changes. The agents that transfer angular momentum between the Earth's components include torques from tangential surface friction and pressure gradients across topographical features. Changes in the gravity field, which can be inferred from satellite perturbations, arise from redistribution of mass within Earth's components. Variations of momentum and mass occur over many timescales, from the highest frequency synoptic, through the intraseasonal and seasonal, to such climate-related signatures as the interannual El Nino/Southern Oscillation and the longer-term, which can involve redistribution of water mass among different reservoirs. This session is aimed at discussing recent results related to momentum and mass budgets and their exchanges, including implications for energetics. It will also highlight the use of modern data sets (e.g., pre-EOS sensors) that are enabling scientists to examine the interactions between components of the Earth system.

Conveners: David A. Salstein, AER, tel: 617-547-6207, fax: 617-661-6479, e-mail: salstein@aer.com; and Byron D. Tapley, University of Texas, tel: 512-471-5573, fax: 512-471-3570, e-mail: tapley@csr.utexas.edu

U03 Earth Gravity Field Modeling and its Applications to Ocean and Earth Sciences (Joint with G, O)

Present and future improvement in Earth's gravity field modeling is anticipated in light of the current space geodesy measurement technologies (satellite laser ranging, Doris, PRARE, GPS, and radar altimetry) and the ones being proposed (satellite gradiometry and other gravity-mapping mission concepts). This session focuses on reviewing a number of gravity missions being proposed, including Bridges, Champ, GPB, Grace, SCG, and Step, and the use of a number of current and future high-low GPS satellite-to-satellite tracking missions (e.g., GPS-Met, GPS-Wakeshield, and Orsted) for improvement of the Earth gravity field model. Papers for the current state in the determination of gravity field models are encouraged. Of particular interest are papers discussing the current research and anticipated improvement in global geoid modeling with applications to the accurate determination of absolute oceanic circulation and to important problems in geophysics, as well as commercial applications, such as petroleum exploration.

Conveners: Bruce Bills, NASA Goddard Space Flight Center, tel: 301-286-8555, fax: 301-286-1616, e-mail: bills@denali.gsfc.nasa.gov; and C.K. Shum, University of Texas/CSR, tel: 512-471-5573, fax: 512-471-3570, e-mail: shum@csr.utexas.edu

U04 Global Climate Change Update: IPCC and the State of the Art (Joint with A, O )

The second major IPCC scientific assessment of climate change will be released publicly in the spring of 1996. The release of the report affords an opportunity for the authors of the various sections of the report to present their respective findings, especially how the scientific results of this updated assessment differ from the final report of Working Group 1 (Climate Change. The Intergovernmental Panel on Climate Change Scientific Assessment) published by Cambridge University Press in 1990. The updated assessment of observed climate variations and change, radiative forcing of climate, sea level change, and other topics will be reviewed.

Convener, Dr. Richard S. Williams Jr., USGS Woods Hole, tel: 508-540-6490, e-mail: rwilliams@nobska.er.usgs.gov

U05 Natural Disaster Reduction: Geophysical, Social, and Policy Components (Joint with A, S, SA, SH, SM, V)

The escalating cost and spreading impact of natural disasters have attracted the concern of peoples and governments worldwide. Population growth, urbanization, technology, and globalizing economies and markets are creating new vulnerabilities to geophysical extremes. However, earthquakes, volcanic eruptions, hurricanes and other severe weather, floods, drought, and geomagnetic storms, need not result in persistent, lingering disruption. Natural disaster reduction therefore promises to be a major societal preoccupation of the 21st century. This session explores the complex, multifaceted dimensions of this formidable challenge, which will require sustained coordinated effort on the part of geophysicists, engineers, social scientists, ecologists, policy makers, and the private sector.

Convener: William Hooke, NOAA, tel: 301-713-0460 ext. 218, fax: 301-713-0666, e-mail: whooke@oar.noaa.gov

Atmospheric Sciences

A01 Historical Perspectives on Climate Change (co-sponsored by the AGU History Committee)

Historical papers on scientific and popular understanding of climatic change and the greenhouse effect are solicited to mark the centennial of Svante Arrhenius's work, "On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground" (1896). Papers on all historical aspects of climate change and on all eras are encouraged.

Conveners, James R. Fleming, Science and Technology Studies, Colby College, Waterville, ME 04901, tel: 207-872-3548, fax: 207-872-3074, e-mail: jrflemin@colby.edu; and William W. Kellogg, 445 College Avenue, Boulder, CO 80302, tel: 303-443-5086

A02 Tropospheric Chemistry

This session will include measurements, modeling studies, and laboratory investigations of tropospheric trace gases, particles, and chemical processes.

A03 Stratospheric Chemistry and Dynamics

Papers are solicited on measurements, modeling studies, and laboratory investigations pertaining to chemical, microphysical, and dynamical processes in the stratosphere. Papers on the chemistry and dynamics of polar ozone depletion will be included in this session.

A04 General Meteorology and Dynamics

Papers are solicited on all aspects of understanding atmospheric dynamics and their interactions with the climate system. Climate system components of interest include land surface, clouds, and the hydrological system.

A05 Aerosol /Cloud Interactions

The effects of aerosols on cloud microphysical and radiative properties are not fully understood, although estimates suggest significant effects on the hydrologic cycle and on climate. Clouds, in turn, act to modify and regulate aerosol abundance, chemical composition, and size. This session includes modeling and observational studies of the interactions between aerosol and both liquid- and ice-phase clouds.

A06 Results of the Gaseous Sulfur Intercomparison Experiment (GASIE) for SO2

An intercomparison experiment for the measurement of sulfur dioxide was performed in fall 1994. Seven leading investigators were challenged with varying levels of sulfur dioxide (nominally 0 to 500 pptv) with differing amounts of added interferents such as ozone, other sulfur gases, and humidity. A gas dilution apparatus was designed and built specifically for this experiment and will be described. The experiment and preliminary data evaluation (on coded data) were conducted under blind conditions to insure the integrity of the intercomparison. After the preliminary data evaluation, all the data were uncoded and reevaluated. This session will discuss all phases of the experiment from planning to final data evaluation. This work was funded by the NSF Division of Atmospheric Chemistry to assess the state of SO2 measurements after a preliminary NASA study indicated there may be problems with the reliability of some field SO2 measurements.

Conveners: George W. Luther III, College of Marine Studies, University of Delaware, Lewes, DE 19958, tel: 302-645-4208, fax: 302-645-4007, e-mail: luther@strauss.udel.edu; and Hilmar A. (Jody) Stecher III, College of Marine Studies, University of Delaware, Lewes, DE 19958, tel: 302-645-4310, fax: 302-645-4332, e-mail: jstecher@strauss.udel.edu

A07 SCAR-B Preliminary Results

The Smoke, Clouds, and Radiation-Brazil (SCAR-B) field experiment was conducted August 16-September 22, 1995, in central Brazil. The purpose of the experiment was to investigate the radiative effects of smoke aerosols from biomass burning on clouds and climate. The field experiment involved coordinated aircraft, surface, and satellite measurements of aerosols from grassland and forest fires in central and northwest Brazil in the dry season. Preliminary results will be presented on data collected from instruments on the NASA ER-2, the University of Washington C-131A, INPE Bandeirante, GOES, NOAA Polar Orbiters, Landsat, and the INPE/GSFC/University of Sao Paulo surface network. These presentations will also focus on the determination of aerosol column loadings, aerosol transport and life times, fluxes, effects of smoke and water vapor on cloud properties, atmospheric corrections, and fires and smoke properties.

Conveners: Yoram Kaufman, NASA Goddard Space Flight Center, Code 913, Greenbelt, MD 20771, tel: 301-286-8228, fax: 301-286-1738, e-mail: kaufman@climate.gsfc.nasa.gov; and David S. McDougal, Mail Stop 483, NASA Langley Research Center, Hampton, VA 23681, tel: 804-864-5832, fax: 804-864-5841, e-mail: d.s.mcdougal@larc.nasa.gov

A08 The Atmospheric Effects of Aircraft

Existing subsonic and proposed supersonic aircraft emit nitrogen oxides, water vapor, carbon dioxide, unburned hydrocarbons, sulfur, and soot into the atmosphere. These exhaust products may have chemical effects on ozone and/or radiative effects on climate. A series of sessions will be held which cover the areas of : (1) exhaust composition and processing in the plume or wake of the aircraft, (2) modeling of the potential global effects of aircraft, (3) atmospheric measurements which help in evaluation of the potential effects of aircraft, and (4) laboratory measurements which bear on the problem of the potential effects of aircraft.

Conveners: Richard Stolarski, Code 916, NASA Goddard Space Flight Center, Greenbelt, MD 20771, tel: 301-286-9111, fax: 301-286-1754, e-mail: stolarski@polska.gsfc.nasa.gov; and Randall Friedl, Code YSM, NASA Headquarters, Washington, DC 20546-0001, tel: 202-358-0776, fax: 202-358-2770, e-mail: rfriedl@mtpe.hq.nasa.gov

A09 Global Carbon Cycle's Role in Global Change

Human activities have significantly altered the atmospheric concentration of carbon dioxide resulting in potential changes in climate, plant growth, and ocean chemistry. Reduction in anthropogenic carbon dioxide emissions attributed to the burning of fossil fuels and changes in land use is being considered as a response option to concerns over global climate change. The behavior of the global carbon cycle will determine, in part, the effectiveness of this option. The focus of this session will be the response of the global carbon cycle inferred from past data and implied by proposed feedbacks between the Earth system and human activities.

Conveners: Haroon Kheshgi, Exxon Research and Engineering, Company Route 22, East Annandale, NJ 08801, tel: 908-730-2531, fax: 908-730-3301, e-mail: hskhesh@erenj.com; and Atul K. Jain, Department of Atmospheric Sciences, University of Illinois, 105 S. Gregory Street, Urbana, IL 61801, tel: 217-333-2128, fax: 217-244-4393, e-mail: jain@uiatma.atmos.uiuc.edu

A10 Factors Affecting Nonpolar Stratospheric Ozone

The bulk of the atmosphere's ozone resides in the tropical and midlatitude stratosphere between 20 and 50 km. Many factors influence ozone in this region of the atmosphere, and the interplay between them are often complex and not well understood. This session will highlight the chemical, dynamical, and radiative processes that regulate ozone in this region of the atmosphere. Of particular interest are analyses of midlatitude ozone loss occurring over the last 15 years.

Conveners: H.A. Michelsen, Atmospheric Research Project, 12 Oxford Street, Cambridge, MA 02138, tel: 617-495-9624, fax: 617-495-4902, e-mail: ham@io.harvard.edu; and A.E. Dessler, NASA Goddard Space Flight Center, Code 916, Greenbelt, MD 20771, tel: 301-286-7540, fax: 301-286-1754, e-mail: dessler@maia.gsfc.nasa.gov

A11 Antarctic and Sub-Antarctic Tropospheric Chemistry

Papers will be considered that involve both experimental and theoretical interpretations of data recorded at fixed sites or from ship/aircraft platforms. Although observations involving both gas phase measurements of sulfur, nitrogen, and carbon species and aerosol measurements will be seriously considered, of particular significance will be studies focused on aspects of sulfur chemistry.

Conveners: D.D. Davis, Earth and Atmospheric Sciences Department, Georgia Institute of Technology, Atlanta, GA 30332, tel: 404-894-3936, fax: 404-894-1993, e-mail: dd16@prism.gatech.edu; and F. Eisele, National Center for Atmospheric Research/ACD, 1850 Table Mesa Road, Boulder, CO 80303, tel: 303-497-1483, fax 303-497-1400, e-mail: eisele@ncar.ucar.edu

Geodesy

G01 Oceanographic and Geophysical Studies Using Satellite Altimetry (Joint with O)

By late 1996, GFO1 will join ERS1, ERS2, and TOPEX/PoSEIDON to allow an unprecedented opportunity for studies of oceanography, geophysics, and glaciology using data from four simultaneously operating high-precision radar altimetric satellites. This session focuses on descriptions of new missions (ERS2 and GFO1) and their data and solicits papers on ocean studies using the highly accurate TOPEX/PoSEIDON measurements. Presentations addressing efforts to achieve highly accurate altimetric measurement systems (orbit determination, calibration/validation, media, and geophysical corrections) are invited. Of particular interest are papers on oceanographic and geophysical studies using present and historic measurements, including Geosat ERM and the newly declassified GM data, and using simultaneous measurements from more than one satellite. Studies of ice sheet mass balances and topography mapping using radar altimetry are also encouraged.

Conveners: Jerome Benenviste, ESA/ESRIN, tel: 011-39-6-941-80-555, fax: 011-39-6-941-80-280, e-mail: Jerome.Benveniste@mail.esrin.esa.it; and John Ries, University of Texas, tel: 512-471-5573, fax: 512-471-3570, e-mail: ries@csr.utexas.edu

G02 Atmospheric Sciences From Spaceborne GPS (Joint with A)

This session will highlight recent results in atmospheric science in which data from spaceborne GPS receivers have played a prominent role. Atmospheric science disciplines will include, but will not be limited to, atmospheric limb sounding, studying of physical processes in the stratosphere and troposphere, and ionospheric tomography. Spaceborne GPS missions (e.g., GPS-Met, Wakeshield) need not be the only science instrument involved, or even the most important, but it should make a strong contribution. Papers involving results from data assimilation for the combination of radio occultation observations with conventional space and in situ measurements for improved numerical weather forecast and climate change research are encourged. Presentations on key or novel technologies for exploiting spaceborne GPS in the general atmospheric science area are also invited.

Conveners: Tom Yunck, Jet Propulsion Lab, tel: 818-354-3369, fax: 818-393-4965, e-mail: tpy@cobra.jpl.nasa.gov; and Michael Exner, UCAR, tel: 303-497-2601, fax: 303-497-2610, e-mail: exner@ncar.ucar.edu

G03 GPS Antenna Models

GPS is rapidly proving that the system can be used to make millimeter precision position determinations in a global scale with temporal resolutions of about one day. One of the limitations of GPS for making measurements with this accuracy on a regular basis is the poor model phase center variations of the omnidirection antennas used in GPS, and the effects of microwave reflectors near GPS antennas. Papers are sought for this session that discuss the determination and accuracy of GPS phase center models, effects of the local microwave environment of GPS antennas, and methods that can be used to mitigate these effects. Papers discussing results from short baseline mixed GPS antenna tests and those discussing the effects of phase center models on global GPS results (e.g., the apparent 10-parts-per-billion-scale error that is introduced when current phase center models are used in global GPS analyses) are of particular interest. Conveners: Thomas A. Herring, MIT, tel: 617-253-5941, fax: 617-253-1699, e-mail: tah@mtglas.mit.edu; and Gerald L.Mader, NOAA/National Geodetic Survey, tel: 301-713-2854, fax: 301-713-4475, e-mail: gerry@mozart.grdl.noaa.gov

G04 Time-Correlated Errors in Geodetic Time Series

This session will address long period correlated errors in the solutions for locations of geodetic sites due to monument motion, orbit error, troposphere and other systematic error sources. Papers are solicited from analysts of GPS, SLR, VLBI, geodimeters, and strainmeter data to discuss these effects and their implications for computing site velocities at the millimeter-per-year level. Papers discussing evidence for the stability of space geodetic monuments are also welcome.

Conveners: Michael M. Watkins, Jet Propulsion Lab, tel: 818-354-7514, fax: 818-393-4965, e-mail: mmw@cobra.jpl.nasa.gov; and Duncan Agnew (tentative), Scripps Institute of Oceanography, tel: 619-534-2590, fax: 619-534-5332, e-mail: dagnew@ucsd.edu

G05 Geodetic Measurements of Past and Present Climate Change

A wide variety of processes involving surface mass change and isostatic rebound, spanning the last glacial cycle to the present, may be studied by interpretation of satellite solutions to the Earth's gravity field, by astronomical observation, and by ground-based measurement with geodetic instruments. Geodetic measurements may be supported with borehole studies, magnetic and temperature measurements, sedimentation, and ocean models. We solicit papers on a broad range of geophysical methods and models employed to study the effects of climate change. These effects may be for paleo or present-day timescales, and are expected to include topics in glacial cycles, postglacial rebound, atmospheric forcing, polar motion, gravity, sea level, and properties of the lithosphere. The session is intended to include topics on the interpretation of satellite data and the improvements in the accuracy and quantity of satellite solutions for the Earth's gravity, sea surface height, tectonic motion, and altimetry. The effects of long-period tides on the interpretation of satellite laser ranging and radar tracking data, VLBI data, and the determination of other time-varying gravitational effects associated with orbital perturbations of satellites are invited for presentation at this session.

Conveners: Andrew Trupin, Vassar College, tel: 914-437-7340, e-mail: trupin@noether.vassar.edu; and Tonie VanDam, NOAA/CIRES, tel: 303-492-5670, e-mail: tonie@robeson.colorado.edu

Geomagnetism/Paleomagnetism

GP01 Antarctic Magnetic Anomalies

International interest in the Antarctic is great because of the central role of its tectonics and geology in Gondwana evolution and the fact that it is the most poorly understood region of the planet. Geologic studies of the Antarctic rely extensively on magnetic anomaly data because of the region's nearly ubiquitous ice cover. Consequently, numerous magnetic surveys have been carried out by the international community. Papers (oral and poster) are solicited that focus on the progress and problems in the acquisition, reduction, analysis, and interpretation of magnetic anomaly data for lithospheric studies of the Antarctic.

Conveners: Ralph R.B. von Frese, Department of Geological Sciences, The Ohio State University, Columbus, OH 43210, tel: 614-292-5635, fax: 614-292-7688, e-mail: vonfrese@osu.edu; and Ash C. Johnson, Geoscience Division, British Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, UK, tel: 44-1223-251579, fax: 44-1223-362616, e-mail: acj@pcmail.nerc-bas.ac.uk

GP02 Magnetic Signatures of Lake Watersheds

Magnetic mineralogy and magnetic granulometry of recent lake sediments and sediment sources in a lake catchment can provide signatures of environmental processes in lake watersheds. This session seeks papers on the use of environmental magnetic techniques alone or in conjunction with nonmagnetic observations (e.g., geochemical, biological) to unravel fundamental processes in lake watersheds.

Convener: K.P. Kodama, Department of Earth and Environmental Sciences, 31 Williams Drive, Lehigh University, Bethlehem, PA 18015-3188, tel: 610-758-3663, fax: 610-758-3677, e-mail: kpk0@lehigh.edu

GP03 Reliability of Sediments as Geomagnetic Field Recorders

Paleomagnetic and rock magnetic records obtained from sedimentary sequences have proven to be useful in providing stratigraphic correlation, proxies of climatic change, and histories of the variation in the morphology and intensity of the geomagnetic field. In each of these cases it is important to evaluate the fidelity of the sediments as magnetic recorders. Papers are solicited for this session which address the reliability of sediment paleomagnetism and rock magnetism, including polarity transition records, relative paleointensity variations, inclination error, compaction effects, rock magnetic indicators of changing redox conditions, and remanence lock-in processes.

Convener: B.M. Clement, Florida International University, Miami, FL 33199, tel: 305-348-3085, fax: 305-348-3877, e-mail: clementb@servms.fiu.edu

GP04 Tectonics of the Neoproterozoic/Paleozoic

The Neoproterozoic/Paleozoic transition marks a unique time in Earth history. This interval marked the rise of the metazoans, the demise of the supercontinent Rodinia, and the formation of Gondwana. Dramatic tectonic, geodynamic, and paleoclimatic changes also occur across this boundary and into the early Paleozoic. This session seeks contributions detailing the paleomagnetic, geologic, geochronologic, and geodynamic history of the Earth during this critical period.

Conveners: Joseph Meert, Indiana State University, Department of Geography and Geology, Terre Haute, IN 47809, tel: 812-237-2270, fax: 812-237-8029, e-mail: gemeert@scifac.indstate.edu; and Trond Torsvik, NGU, Leif Eriksonne vei 39, N-7040, Trondheim, Norway, tel: 47-73 90 40 11, fax: 47-73 90 44 94, e-mail: trond.torsvik@ngu.no

Hydrology

H01 Fluvial Geomorphology and Models of River Basin and Landscape Evolution

Interest in quantitative fluvial geomorphology has increased in the last 15 years. Much of that effort has gone into relating patterns and form to processes in the basin. Descriptive and predictive models have been suggested. This session seeks to provide a forum and focus for recent advances. Papers are requested in the areas of (1) basin and landscape evolution models, (2) scales and scaling, and (3) deterministic and stochastic representation of basin- and landscape-forming processes.

Conveners: Rafael Bras, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, tel: 617-253-2117, fax: 617-253-4546, e-mail: rlbras@mit.edu; and Peter K. Haff, Center for Hydrologic Science, Department of Geology, Duke University, Durham, NC 27708-0230, tel: 919-684-5902, fax: 919-684-5833, e-mail: haff@ibex.geo.duke.edu

H02 Impacts of High-Performance Computing on Practical Groundwater Problems

High-performance computing, ranging from high-speed microcomputers to massively parallel computers, is combined with communications networks to reduce computational limitations on challenging groundwater problems facing the nation. Papers will be solicited on the solution of real-world problems in groundwater that are computationally intensive. Topics acceptable for this session include the following: intensive grids, coupled models, inverse models, Monte Carlo simulations, optimization and management, availability of simulation codes, types of problems amenable to specific architectures and actual performance applications to identifiable field sites, visualization of large problems, educational issues relating to dissemination of these advances through the community, and examination of scientific, engineering, and business limits of applicability. At a recent AGU meeting, a variety of algorithmic issues in scientific computing relating to groundwater were presented and explored. This session will focus on "application computing" rather than scientific computing.

Conveners: Laura Toran, Oak Ridge National Laboratory, P.O. Box 2008, Mailstop 6352, Oak Ridge, TN 37831, tel: 423-574-7976, fax: 423-576-8143, e-mail: lto@ornl.gov; and David E. Dougherty, Department of Civil and Environmental Engineering, University of Vermont, 379 Votey Building, Burlington, VT 05405-0156, tel: 802-656-1920, fax: 802-656-8446, e-mail: David.Dougherty@uvm.edu

H03 Beyond Parameter Uncertainty: Comprehensive Evaluation of Prediction Uncertainty in Groundwater Flow and Transport Modeling

Modeling flow and transport in groundwater systems requires information about a variety of factors that are always subject to uncertainty. The natural way to approach this situation is to build a model that incorporates these uncertainties and propagates them to the final results. However, this is seldom done in practice; most models are built disregarding uncertainty altogether or, at best, considering the uncertainty of a single parameter (e.g., hydraulic conductivity is a single physical parameter, regardless of whether it is a lumped or distributed parameter in the model). But prediction uncertainty is also affected by other factors, such as uncertain boundary conditions (e.g., recharge and other input fluxes), uncertain characterization of the internal geometry of the system (e.g., location and extent of less permeable layers), and even uncertainty about the conceptual model of the system (e.g., chemical and biological reactions affecting transport of a particular solute, characteristics of a contaminant source, etc.). These disparate factors are usually considered via assumptions and simplifications at the model conceptualization stage, thus neglecting their uncertainty and precluding a comprehensive evaluation of prediction uncertainty. This special session will explore modeling approaches that take a holistic view of the uncertainty evaluation process, emphasizing the quantitative evaluation of all the possible sources of uncertainty and their impact on model predictions. Contributions that address this issue are invited. Papers that focus on methodological issues, application concerns, and case studies are appropriate.

Conveners: Hernan A. M. Quinodoz, Kansas Geological Survey, The University of Kansas, 1930 Constant Avenue, Lawrence, KS 66047-3726, tel: 913-864-3965, fax: 913-864-5317, e-mail: hernan@kgs.ukans.edu; and John M. Shafer, Director, Earth Sciences and Resources Institute, University of South Carolina, 901 Sumter St., Columbia, SC 29208, tel: 803-777-4421, fax: 803-777-6437, e-mail: jshafer@esri.esri.sc.edu

H04 Processes Which Influence Matrix Diffusion in Fractured Media

It is now well-recognized that the transport of contaminants through fractured geological media is significantly influenced by the process of diffusive transfer from the fractures to the unfractured material. In fact, this process has widespread importance in the geological sciences, from influencing the age dating of waters and rock to producing mineral alteration halos around fractures. When interpreting diffusive transport, the parameters, including porosity, which govern the transfer are often lumped together using an effective diffusion coefficient. This is undertaken with the knowledge that it may be possible to explicitly define microscale processes such as osmosis, pore-size exclusion, and surface diffusion in our interpretive models. We are equally as approximate in the interpretation of adsorption under conditions of diffusive transport. In this case, it is necessary to relate the surface adsorption on the fracture face to the adsorption processes internal to the medium, which can be significantly different. Thus the purpose of this special session is to bring together scientists who conduct experiments involving the processes of diffusion at the field scale with those who investigate microscale processes in the laboratory, using theory and experiment. Papers should focus on aspects of measurement, theory and significance at the macroscopic scale. Papers relating results and theory at several scales are particularly encouraged.

Conveners: K. Novakowski, National Water Research Institute, Environment Canada, 867 Lakeshore Rd., Burlington, ONT L7R 4A6 Canada, e-mail: Kent.Novakowski@CCIW.ca; and G. van der Kamp, National Hydrology Research Institute, Environment Canada, 11 Innovation Blvd., Saskatoon, SK S7N 3H5 Canada, e-mail: vanderkampg@nhrisv.nhrc.sk.doe.ca

H06 New Directions in the Study of Surface Runoff-Generation

The study of surface runoff generation processes is being revisited for several reasons. These include availability of new tools such as GIS-based modeling, renewed interest in practical applications such as nonpoint source pollution control, and increased awareness of the extent of spatial variability of the runoff generating processes themselves. Papers are invited that report experimental studies, tools, or conceptual developments in the study of runoff-generation. Appropriate topics include, but are not limited to, remote sensing, subsurface-surface interactions, variable-source-area hydrology, GIS, and distributed computer models.

Conveners: W.J. Gburek, USDA-ARS, Pasture Lab Building, University Park, PA 16802-3702, tel: 814-863-8763, fax: 814-863-0935, e-mail: jaz5@psu.edu; and J. A. Zollweg, USDA-ARS, Pasture Lab Building, University Park, PA 16802-3702, tel: 814-863-8763, e-mail: jaz5@psu.edu

H07 Fluvial Processes and River Mechanics This special session will focus on the general topic of fluvial processes, with an emphasis on river mechanics. Field, laboratory, and modeling (analytical or numerical) studies are solicited. Invited speakers will emphasize recent progress in understanding the adjustment of river morphology to a variety of controlling variables.

Conveners: Panos Diplas, Department of Civil Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, tel: 540-231-6069, fax: 540-231-7532, e-mail: pdiplas@vt.edu; and Jim Pizzuto, Department of Geology, University of Delaware, Newark, DE 19716, tel: 302-831-2710, fax: 302-831-4158, e-mail: pizzuto@brahms.udel.edu

H08 Hydrograph Separation Techniques in Catchment Hydrology

The event hydrograph constitutes the single best integrative measure of catchment hydrologic behavior. Hydrograph separation techniques, particularly those using chemical and isotopic tracers, have proved to be powerful tools for determining sources of solutes and partitioning hydrographs into flow path components. However, recent challenges to standard assumptions, such as constant isotopic compositions and conservative solute behavior of end members, have brought some established techniques under scrutiny. Chemical, isotopic, hydrometric, and graphical/numeric results sometimes lead to conflicting interpretations of catchment function. This session aims to critically evaluate the state of the art of hydrograph separation techniques.

Conveners: Jamie Shanley, USGS, P.O. Box 628, Montpelier, VT 05601, tel: 802-828-4466, fax: 802-828-4465, e-mail: jshanley@usgs.gov; and Jeff McDonnell, SUNY-ESF, 1 Forestry Dr., Syracuse, NY 13210, tel: 315-470-6565, fax: 315-470-6956, e-mail: jemcdonn@mailbox.syr.edu

H09 Education and Public Outreach in the Hydrologic Sciences

Hydrologists are increasingly required to explain (and to justify) their studies to a lay audience. Frequently, however, they don't have sufficient guidance or expertise to know how to best reach such an audience. Posters (paper, computer, and multi-media) are solicited to allow attendees to share experiences of what techniques are most effective. Appropriate for this session are design considerations for traditional publications (posters, brochures, and field trips), for new methods (interactive computer demonstrations, World Wide Web home pages, CD-ROMs), and for other public involvement techniques (for example, volunteers for field studies).

Conveners: Rick Hooper, USGS, 3039 Amwiler Road, Suite 130, Atlanta, GA 30360, tel: 770-903-9146, fax: 770-903-9199, e-mail: rphooper@usgs.gov; and Dave Genereux, Geology Department, Florida International University, Miami, FL 33199, tel: 305-348-3119, fax: 305-348-3877, e-mail: GENEREUX@servms.fiu.edu

H10 Environmental Geochemistry

Papers and posters are solicited on environmental geochemical techniques, including laboratory studies, field investigations, and modeling advances. A broad spectrum of topics is appropriate for this session, including redox processes in wetlands, flowpath determinations using combined geochemical and hydrometric techniques, biogeochemical cycling, mineral weathering, degradation of organics, and site remediation efforts.

Conveners: Jake Peters, USGS, 3039 Amwiler Road, Suite 130, Atlanta, GA 30360, tel: 770-903-9145, fax: 770-903-9199, e-mail: nepeters@usgs.gov; and Julie Sueker, USGS, Denver Federal Center, MS 413, Lakewood, CO 80225, tel: 303-940-0287, fax: 303-236-5034, e-mail: jksueker@usgs.gov

H11 Surgical Strikes: Low-Cost Applications of Isotopes for Solving Environmental Problems

Environmental isotopes are powerful tools for solving many hydrologic and geochemical problems. In particular, the integrating (in both space and time) nature of isotope signatures can overcome one of the perpetual problems that hinders Earth science investigations: insufficient data. However, isotopes are generally not a conventional tool for environmental studies. We solicit examples of low-cost, practical applications of small data sets. We especially welcome presentations showing how small sets of isotope data have produced major changes in conceptual framework and/or have dramatically affected the later development of hydrologic models. The session will include a panel discussion on the uses of isotopes in environmental studies.

Conveners: Kip Solomon, University of Utah, Department of Geology and Geophysics, 719 Browning Bldg., Salt Lake City, UT 84112-1183, tel: 801-581-7231, fax: 801-581-7065, e-mail: ksolomon@mail.mines.utah.edu; and Carol Kendall, USGS, 345 Middlefield Road, MS 434, Menlo Park, CA 94025, tel: 415-329-4576, fax: 415-329-4538, e-mail: ckendall@usgs.gov

H12 Use of Biology in Water Quality Investigations

Both hydrogeochemical and biological investigations in streams and rivers are often focused on similar water quality problems, yet these disciplines are often not integrated within the same study. Water quality judgments are often made using thresholds obtained from laboratory studies without regard to actual effects of contaminants or stresses in the field, and biological indicators are often applied without regard to actual environmental stresses that affect the indicators. The purpose of this special session is to bring together hydrogeochemists and biologists to share information on how their disciplines can be integrated in water quality investigations. Contributions are solicited on (1) combining physical, chemical, and biological factors to investigate water quality; (2) the effect of environmental stressors on aquatic biota in the field; and (3) the role of community structure in assessing water quality status or trends.

Conveners: Patrick J. Phillips, USGS, 425 Jordan Road, Troy, NY 12180, tel: 518-285-5667, fax: 518-285-5601, e-mail: pjphilli@usgs.gov; and Jeroen Gerritsen, Tetra Tech, 10045 Red Run Blvd., Owings Mills, MD 21117, tel: 410-356-8993, fax: 410-356-9005, e-mail: jgerrits@aip.org

H13 Environmental Isotope Applications in Hydrologic Studies of Agricultural Landscapes

Agricultural landscapes host a variety of hydrologic processes that are amenable to study with environmental isotopes. We invite presentations on the uses of isotopes as tracers of water and solutes and indicators of biogeochemical processes in agricultural settings. Topics might include: distinguishing matrix- and preferential-flow components of infiltration, determining residence times of soil water, hydrograph separation in agricultural watersheds, documenting the effects of tile drains on the hydrology of agricultural watersheds, nitrogen cycling in agricultural settings, and tracing dissolved constituents from fertilizers. Especially welcome are talks about how isotopes have been used to evaluate agricultural best-management practices and installations such as vegetated filter- and buffer strips.

Convener: Steve Komor, U.S. Geological Survey, 2280 Woodale Drive, Mounds View, MN 55112, tel: 612-783-3236, fax: 612-783-3236, e-mail: SCKOMOR@usgs.gov

H14 Environmental Cleanup Efforts: Are They Working? If Not, Why Not?

A high level of public interest in environmental protection has resulted in environmental regulations and resource management strategies to clean up our rivers, lakes, and groundwater resources. There have been many successes: scores of formerly polluted rivers and lakes have now been reopened to recreational use, and native plants and animals are returning to many wetlands and coastal areas; but many challenges remain. The purpose of this session is to present cases studies about cleanup successes and failures; discuss what resource management strategies have been effective or ineffective, and why; consider what scientific questions need to be addressed to improve future environmental monitoring, assessment, and remediation plans; and discuss how local community efforts have contributed to improvements in water quality. The session will include a panel discussion.

Conveners: Carol Kendall, USGS, 345 Middlefield Road, MS 434, Menlo Park, CA 94025, tel: 415-329-4576, fax: 415-329-4538, e-mail: ckendall@usgs.gov; and Virginia Carter, USGS, 12201 Sunrise Valley Dr., MS 430, Reston, VA 22092, tel: 703-648-5897, fax: 703-648-5484, e-mail: vpcarter@usgs.gov

H15 Hydrologic Budget Components During Extreme Precipitation Regimes Over the Midwestern United States (Joint with A)

This session addresses components of the water balance over the Great Plains during seasonal drought or flood regimes, particularly the 1988 drought and 1993 flood. The aim of the session is to clarify the roles of specific processes in the maintenance of these seasonal hydrologic anomalies. Some examples of these processes include large-scale circulation anomalies, regional circulations (such as the low-level jet), and feedbacks due to evapotranspiration. Papers on individual events are appropriate to the extent that they relate to the larger context of the seasonal droughts and floods. Both observational and modeling studies are solicited.

Conveners: Raymond W. Arritt, Department of Agronomy, Iowa State University, Ames, IA 50011, tel: 515-294-9870, fax: 515-294-3163, e-mail: rwarritt@iastate.edu; and Allen Bradley, University of Iowa, Institute of Hydraulic Research 404 Hydraulics Laboratory, Iowa City, IA 52242-1585, tel: 319-335-6117, fax: 319-335-5238, e-mail: abradley@iihr.uiowa.edu

H16 Remote Sensing of Precipitation-Posters (Joint with A)

This special session will cover a broad range of topics related to the remote sensing of precipitation. The session will consist entirely of poster presentations. Papers are solicited on the estimation, validation, and error analysis of precipitation measured by ground-based remote sensors, such as radar (e.g., NEXRAD WSR-88D), and satellite sensors (e.g., VIS, IR, SSM/I). The session will highlight research and applications involving remotely sensed precipitation. Presentations related to the GEWEX Continental Scale International Project (GCIP), the Tropical Rainfall Measuring Mission (TRMM), and the TOGA Coupled Ocean-Atmosphere Experiment (COARE) are particularly encouraged.

Conveners: Matthias Steiner, Department of Civil Engineering and Operations Research, Princeton University, Princeton, NJ 08544, tel: 609-258-4614, e-mail: msteiner@radap.princeton.edu; and Mark Morrissey, Oklahoma Climate Survey, Department of Geography, University of Oklahoma, Norman, OK 73019, tel: 405-325-2541; e-mail: mmorriss@uoknor.edu

H17 Ecohydrology at Large Scales (Joint with A)

This special session is being organized by the IGBP Core Project Biospheric Aspects of the Hydrologic Cycle Project (BAHC) and in recognition of the importance of coupled climate-hydrology-vegetation models for predicting ecosystem responses to environmental changes, e.g., elevated carbon dioxide levels. Papers are solicited on the following topics: global distribution of biome types and their mapping, potential and actual vegetation distributions, the use of remotely sensed data, dynamic vegetation/climate interaction, the role of soils and soil moisture, and the effects of terrestrial biosphere on the quantity and quality of river-borne fluxes.

Conveners: Christopher Field, Department of Plant Biology, Carnegie Institute of Washington, 290 Panama St., Stanford, CA 94305-1297, tel: 415-325-1521 ext. 213, fax: 415-325-6857, e-mail: chris@jasper.stanford.edu; and T. Schmugge, USDA Hydrology Lab, Beltsville, MD 20705-2350, tel: 301-505-8554, fax: 301-504-8931, e-mail: schmugge@hydrolab.arsusda.gov

H18 Downscaling and Disaggregation Issues (Joint with A)

This special session is being organized by the IGBP Core Project Biospheric Aspects of the Hydrologic Cycle Project (BAHC) and deals with problems of using large-scale information, e.g., GCM output, in regional-scale applications. Papers are solicited on the following topics: stochastic and dynamic downscaling, nesting of dynamic models at different spatial scales; downscaling algorithm calibration, intercomparison and evaluation; risk related downscaling; and analysis of the impacts of uncertainty in simulation models.

Conveners: Jeff Brook, Atmospheric Environment Service, ARQP, 4905 Dufferin St., Downsview, Ontario M3H5T4, Canada, tel: 416-739-4916, fax: 416-739-5708, e-mail: arqpjbk@dow.on.doe.ca; and Joseph Russo, ZedX, Inc. P.O. Box 404, Boalsburg, PA 16827-0404, tel: 814-466-2025, fax: 814-466-6691, e-mail: joe@meso.com

H19 Spatial Patterns of Vegetation and Soil Moisture, and Their Impact on Hydrologic Processes (Joint with A)

This symposium will focus on the spatial variability of vegetation and soil moisture and their impact on the hydrologic processes. Issues to be addressed include the following: the short-term interdependence of soil moisture, and vegetation on precipitation patterns and evaporation rate on soil moisture and vegetation; the effect of scaling on the level of impact; methods of measuring the spatial variation of precipitation; soil moisture, vegetation and evaporation; techniques for characterizing spatial variability; and relationships between model variables and observations.

Conveners: A. Hall, Office of Hydrology, NOAA/NWS (W/OHx3), 1325 East-West Highway, Silver Spring, MD 90210, tel: 301-713-1017, fax: 301-713-1051, e-mail: ahall@smtpgate.smcc.noaa.gov; and D. Chen, School of Engineering, University of Manchester, M13 9PL, UK, tel: 44-161-275-4354, fax: 44-161-275-4361, e-mail: daoyi@mw53.eng.man.ac.uk

H20 Observational and Modeling Studies of Soil Moisture Across a Range of Space and Timescales (Joint with A)

This session solicits presentations on novel and innovative approaches to better understand, model, measure, and analyze soil moisture fields. Observational, remote sensing, and modeling studies are welcome, as are papers addressing mesoscale and global climate model studies that illustrate the influence of soil moisture on surface and near-surface processes across a range of space and timescales. This session intends to provide a forum for experimental scientists and numerical modelers to present results and exchange ideas on mutual needs for future soil moisture studies.

Conveners: Shafiqul Islam, Cincinnati Earth System Science Program, University of Cincinnati, P.O. Box 210071, Cincinnati, OH 45221-0071, tel: 513-556-1026, fax: 513-556-2599, e-mail: Shafiqul.Islam@uc.edu; and Ted Engman, NASA/Goddard Space Flight Center, Hydrological Sciences Branch, Code 974, Greenbelt, MD 20705, tel: 301-286-5355, fax: 301-286-1758, e-mail: tengman@neptune.gsfc.nasa.gov

H21 Instrumentation and Data Analysis in Hydrometeorology (Joint with A)

A one-day special session will be held on instrumentation and data analysis in hydrometeorology. The morning section will consist of five invited lectures of 40 minutes each. The five lectures will cover (1) point instrumentation in the atmospheric boundary layer, (2) aircraft, (3) Infrared and microwave remote sensing, (4) lidar, and (5) radar. These introductory lectures will present fundamental principles of the instrument physics and what they measure; instrument range, resolution, accuracy, sensitivity, and implications for operation in practice; and type of data obtained and application of these data to develop information useful in hydrometeorology. In addition, the discussion could include future applications of the instruments in the field. The afternoon session will be a poster-only session, and presentations are solicited on measurement and interpretation of data in hydrometeorology, including instrument development and operation, analysis of data collected from remote sensing and other field devices, issues on data processing, the measurement and estimation of land surface heat fluxes, gas transfer, land surface temperature and soil moisture content, precipitation, and atmospheric boundary layer structure in the context of hydrologic and atmospheric studies.

Conveners: Marc B. Parlange, Hydrologic Science, University of California, Davis, CA 95616, tel: 916-752-4953, fax: 916-752-5262, e-mail: mbparlange@ucdavis.edu; and William Kustas, USDA-ARS Hydrology Lab., Beltsville, MD 20705, tel: 301-504-8498, e-mail: bkustas@hydrolab.arsusda.gov

H22 Large-Scale Field Experimentation and Remote Sensing: Results and Opportunities (Joint with A)

In the past decade a number of carefully planned campaigns involving ground-based measurements, in concert with remotely sensed observations from satellites and aircraft and various types of modeling activities, have gradually started to unravel several issues in land surface-atmosphere interactions and the related hydrology. These experiments have covered a wide spectrum of spatial and temporal scales, ranging from the micro- to the mesobeta and from the quasi-instantaneous to the monthly, respectively. Although much remains to be done, it is widely recognized that there has been considerable progress, which has already led to improved understanding of the underlying mechanisms and to improved parameterizations for climatic and hydrologic modeling purposes. The objective of this session is to take stock of recent results, with successes and failures, and to consider prospects for clarifying unresolved issues. This includes the use of state-of-the art models to improve the planning of intensive field campaigns by emphasizing the specific locations and time periods particularly relevant for the processes of interest. Papers on the potential benefits/dangers of implementing modeling studies in experimental design are also desired in this session.

Conveners: Wilfried Brutsaert, Department of Civil and Environmental Engineering, Hollister Hall, Cornell University, Ithaca, NY 14853, tel: 607-255-3676, fax: 607-255-9004, e-mail: whb@hydro1.cee.cornell.edu; and Roni Avissar, Department of Environmental Sciences, Cook College, Rutgers University, New Brunswick, NJ 08903, tel: 908-932-3482, fax: 908-932-8644, e-mail:avissar@gaia.rutgers.edu

Mineralogical Society of America

M01 Impact Mineralogy: A Tribute to Robert S. Dietz (revised title)

In recent years, there has been a focus of interest in the role of impacts as a crustal process. This session will explore the effects of impacts on the mineral assemblage of both the target rocks as well as the impactor. A broad spectrum of disciplines (from field geology through laboratory studies to theoretical physics) is required to describe and understand these mineralogical changes. It is hoped that a better appreciation of the role played by impacts on mineral genesis and alteration will result and that criteria for recognition of ancient and/or severely eroded impact sites can be developed.

Conveners: Patrick T. Taylor, Code 921, NASA/GSFC, Greenbelt, MD 20771, tel: 301-286-5412, fax: 301-286-1616, e-mail: ptaylor@ltpmail.gsfc.nasa.gov; Ronald W. Girdler, Department of Physics, University of Newcastle upon Tyne, Newcastle upon Tyne, NE1 7RU, UK, tel: 44-608-222-7299, fax: 44 191 222-7361, e-mail: R.W.Girdler@newcastle.ac.uk; Peter S. Fiske, Institute of Geophysics and Planetary Physics, Lawrence Livermore National Laboratory, Livermore, CA 94550, tel: 510-422-4912, fax: 510-423-0238, e-mail: fiske@sunlight.llnl.gov

Ocean Sciences

O01 Monitoring the Coastal Ocean

The coastal ocean, including marshes and estuaries, is of increasing human importance. The coastal ocean has great impact on human activity and is greatly impacted by human activity. This session focuses on monitoring of the coastal ocean for water level, circulation, pollutants, and general environmental health. Papers describing the use of in situ observing systems, remote sensing, and numerical models are solicited.

Convener: Steve Gill, Ocean and Lake Levels Division, NOAA/NOS, 1305 East-West Highway, Silver Spring, MD 20910; tel: 301-713-2890; fax: 301-713-4436, e-mail: gill@wlnet1.nos.noaa.gov

O02 Flow Through Wetland and Marine Vegetation

This session will focus on the hydrodynamics of wetland and marine vegetation, and their connection to system processes such as dispersion, sediment deposition, and larval recruitment. For example, topics of interest include (1) modeling and/or observations of the mean and turbulent flow fields within vegetation, (2) particle deposition and trapping within a plant canopy, and (3) turbulent diffusion and dispersion.

Convener: Heidi Nepf, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, tel: 617-253-8622, fax: 617-258-7009; e-mail: hmnepf@mit.edu

O03 Human Impacts on the Coastal Ocean

The majority of the world's population lives in the coastal zone. Human activity profoundly influences the coastal ocean in many ways, including pollution, destruction of habitat, and alteration of flow by manmade structures. Much of human enterprise depends upon the coastal ocean for transportation, recreation, and as a food source. Papers are solicited on all aspects of human impacts on the coastal ocean, including efforts to mitigate adverse impacts.

Convener: Mark E. Luther, University of South Florida, Department of Marine Science, 140 Seventh Avenue South, St. Petersburg, FL 33701, tel: 813-893-9528, fax: 813-893-9189, e-mail: luther@marine.usf.edu

O04 Ice Cores: Paleoclimates and Glaciology (Joint with A and H)

Ice core results from Greenland, Antarctica, and other locations around the world provide exceptional historical information on our dynamic climate system. Detailed analyses have documented variations in chemical, accumulation, and particulate records that assist in the definition of critical climate conditions. General circulation model results, constrained by these data, allow further examination of the factors controlling changes between and within paleoclimate phases. Papers are invited on other aspects of ice core research projects such as field work, remote sensing, and modeling.

Conveners: Christopher A. Shuman, Oceans and Ice Branch, NASA Goddard Space Flight Center, Mail Code 971, Greenbelt, MD 20771, tel: 301-286-8725, fax: 301-286-0240, e-mail: shuman@hardy.gsfc.nasa.gov; and James W.C. White, Institute for Arctic and Alpine Research and Department of Geological Sciences, University of Colorado, Campus Box 450, Boulder, CO 80309, tel: 303-492-5494, fax: 303-492-6388, e-mail: jwhite@spot.colorado.edu

O05 Late Pleistocene Chronology: Corals, Deep-Sea Sediments, and Inorganic Carbonates

Thermal ionization mass spectroscopy has in recent years improved 230Th/U and 234/238U radiometric dating of U-bearing carbonates with higher precision and smaller sample sizes. These new data have confirmed older data in large part but have ignited several hot controversies: (1) What is the age and duration of oxygen isotope stage 5e? (2) Were there significant high stands of sea level before 5e as it is known in the marine O18 record? (3) Is the orbitally tuned Milankovitch SPECMAP marine age scale accurate? In addition to successful use in reef-building corals (and not-so-successful work in molluscs), these dating techniques are now being applied to a wide variety of other carbonates: speleothems, groundwater calcite crusts, algal aragonite, deep-sea corals, and others. Papers which make some headway towards an absolute marine chronology are invited, as well as papers concerned with other relevant chronologies (e.g., continental).

Convener: Edward A. Boyle, Department of Earth, Atmosphere, and Planetary Sciences, Rm. E34-258, Cambridge MA 02139, tel: 617-253-3388, fax: 617-253-8630, e-mail: eaboyle@mit.edu

O06 LGM Pole-Equator Temperature Gradient (Joint with A)

Recent borehole studies have suggested that the Arctic temperatures during the LGM were much colder than previously thought, and subtropical SSTs have also been estimated as colder than previously estimated. How well do we know the pole-equator gradient during the LGM throughout the globe? Papers are invited on ice-core, terrestrial (pollen, macrofossils, tree rings, isotopes), and marine data as well as on climate modeling to address this question.

Convener: Dorothy Peteet, NASA/GISS, 2880 Broadway, New York, NY 10025, tel: 212-678-5587 and 914-365-8420, fax: 914-365-8154, e-mail: peteet@ldeo.columbia.edu

O07 Paleoceanography of the Atlantic Basin: ODP Results

Results from the Ocean Drilling Program continue to lead the way in elucidating the paleoenvironmental evolution of the Atlantic Ocean Basin and the role it plays in global ocean and climate systems. This session focuses on recent ODP results and syntheses that emphasize paleoceanography and paleoclimatology.

Conveners: William Showers, Department of MEAS, North Carolina State University, Raleigh, NC 27695-8208, tel: 919- 515-7143, fax: 919-515-7802, e-mail: W_Showers@ncsu.edu; and John Farrell, Joint Oceanographic Institutions, Inc., 1755 Massachusetts Ave., NW, Suite 800, Washington, DC 20036-2102, tel: 202-232-3900 ext. 211, fax: 202-232-8203; e-mail: jfarrell@brook.edu

O08 Paleoceanography and Paleoclimatology: Observation and Models (Joint with A)

Papers are invited on any topic in paleoceanography and paleoclimatology; this is an at-large session, with all-volunteered contributions covering all timescales, for abstracts that do not fit into one of the special theme sessions.

Conveners: J.F. McManus, Lamont Doherty Earth Observatory, Palisades, NY 10964, tel: 914-365-8571, fax: 914-365-2312, e-mail: jmc@lamont.ldeo.columbia.edu; and J. L. Cullen, Department of Geological Sciences, Salem State College, Salem, MA 01970, tel: 508-741-6282, fax: 508-741-6132, e-mail: cullen@dgl.ssc.mass.edu

O09 Hydrodynamic and Biodynamic Cycles in Estuarine Ecosystems

Recent data indicate that estuarine ecosystems are much more adaptable to change than previously thought. In some cases large shifts in communities at lower trophic levels have little effect on higher trophic levels. This session will explore recent developments in ecosystem dynamics in estuaries.

Conveners: Gary Kleppel, Nova Southeastern University Oceanographic Center, 8000 North Ocean Drive, Dania, FL, e-mail: kleppel@ocean.nova.edu; and Carm Tomas, Florida Marine Research Institute, 800 First Street South, St. Petersburg, FL 33701, tel: 813-896-8626

Planetology

P01 Galileo Jupiter Encounter (joint with A, SM)

The Galileo Probe entered the atmosphere of Jupiter on December 7, 1995. The Galileo Orbiter went into orbit about Jupiter on the same date, and will explore the jovian system for almost two years. This session is devoted to reporting results from this historic encounter with Jupiter. The session will include invited papers, and contributed papers as space permits.

Conveners: R. E. Young, NASA Ames Research Center, M/S 245-3, Moffett Field, CA 94035-1000, tel: (415)604-5521, fax: (415)604-6779, email: ryoung@humbabe.arc.nasa.gov; and T. V. Johnson, Jet Propulsion Laboratory, M/S 264-419, 4800 Oak Grove Dr, Pasadena, CA 91109, tel: (818)393-7957, fax: (818)393-4530, email: tjohnson@jpltvj.jpl.nasa.gov.

P02 Prospects for the Geophysical Exploration of Mars

With the large number of missions planned for Mars in the next decade, including both orbiting and landed instrument packages, there should be unprecedented opportunities to undertake geophysical investigations of the planet to elucidate its interior structure and processes. Papers are invited on geophysical measurements and observations that could be made or are planned in the next decade, as well as on new models and techniques that could help to interpret this new (as well as the old) data.

Conveners: Bruce Banerdt, Jet Propulsion Laboratory, Mail Stop 183-501, 4800 Oak Grove Drive, Pasadena, CA 91109, tel: 818-354-5413, fax: 818-393- 9226, e-mail: bruce.banerdt@jpl.nasa.gov; and Tilman Spohn, Institut fur Planetologie, Westfailia Wilhelms-Universitat, Wilhelms-Klemm-Strasse 10, D48149 Muenster, Germany, tel: 49-251-83-3566, fax: 49-251-83-9083, e-mail: spohn@uni-muenster.de

P03 Galilean Satellite Geology and Geophysics

This session focuses on geological and geophysical analyses of the Galilean satellites from Voyager, HST, and Earth-based observations. Specific contributions are solicited which highlight pre-Galileo encounter states of knowledge about processes and histories, and about predictions and tests that can be made with Galileo data. Studies of other outer planets' satellites that are relevant to the understanding of the Galilean satellites are also of interest, as are plans for satellite observations during the Galileo mission.

Conveners: James Head, Department of Geological Sciences, Brown University, Box 1846, Providence, RI 02912, tel: 401-863-2526, fax: 401-863-3978, e-mail: head@pggipl.geo.brown.edu; and Torrence Johnson, Jet Propulsion Laboratory, MS 183-501, 4800 Oak Grove Dr., Pasadena, CA 91109, tel: 818-393-7957, fax: 818-393-4530, e-mail: tjohnson@jpltvj.jpl.nasa.gov

Seismology

**LATE-BREAKING SESSION**

S01 Tsunamigenic earthquakes of February 1996: Biak and Peru

On 17 February 1996 at 05:59 GMT, a major earthquake occurred near Biak Island, Indonesia (0.5S, 136E). This earthquake has a Harvard "QUICK CMT" moment of 2.2 10**28 dyne-cm and the preliminary mechanism suggests a low-angle thrust event. The Biak earthquake has several interesting characteristics: it generated a tsunami which was recorded and did some damage in Japan (nearly 1 m). Also, it was followed within one day by a flurry of aftershocks featuring an unusual diversity of focal mechanisms: thrust, normal, and strike-slip (over a 60 km * 60 km area). The event occurred in a region with little seismic activity, and the thrusting nature of the event suggest a complicated tectonic interaction for this region.
On 21 February 1996 at 12:51 GMT, another tsunami-generating earthquake occurred, this one located off the coast of northern Peru (9.6S, 80.2W). Inspection of teleseismic, broad-band body waves indicates that this event had a complex rupture. Another unusual aspect of this earthquake is the discrepancy between the surface-wave and moment magnitudes (Ms 6.8, Mw 7.5), which normally agree better for shallow events. This discrepancy is similar to classic tsunamigenic events with a relatively slow rupture characteristic. This event produced local tsunamis of several meters, and Mid-Pacific heights reaching 50 cm, in excess of the waves expected from the seismic moment of the parent earthquake (approx. 2 10**27 dyne-cm).
We invite submissions to this late-breaking special session at the Spring AGU Meeting regarding all aspects of these earthquakes and their associated tsunamis.

Convener: Emile Okal, Northwestern University, Department of Geological Sciences, Evanston, IL 60208; emile@earth.nwu.edu.

ABSTRACTS: Deadline is March 13, 1996
(Extended for this late-breaking session only)

Submit abstracts in the standard AGU format directly to AGU:

American Geophysical Union
2000 Florida Avenue N.W.
Washington D. C. 20009

Only hard-copy abstracts will be accepted.
Include a note stating that the abstract is for the late-breaking seismology special session S01
If you have already submitted an abstract to this meeting (as a first author) on another topic, you may still submit a presentation to these sessions, but only one (first-author) presentation per person in the late-breaking session.

If you need additional information, Contact the convener or Chuck Ammon, Saint Louis University ammon@eas.slu.edu

SPA: Aeronomy

SA01 Space Tethers (Joint with SM)

This joint session is being organized to allow early dissemination of results from the TSS-1R and OEDIPUS-C tether missions. Space tether technology is now reaching a level of maturity where its use for a broad range of scientific applications appears feasible. Presentations on future applications using space tethers for magnetospheric, ionospheric, thermospheric, and mesospheric (MITM) science from expendable launch vehicles, shuttles, or the space station are also encouraged.

Conveners: B. Gilchrist, University of Michigan, e-mail: gilchrst@eecs.umich.edu; and W. Raitt, Utah State University, e-mail: raitt@demise.cass.usu.edu

SA02 Thermospheric and Mesospheric Studies Using Combined Radio and Optical Techniques

Results obtained from the combined usage of radio and optical measurements for the study of the structure and dynamics of the mesosphere and thermosphere are solicited. In addition, papers dealing with the computation of the atomic oxygen ion-neutral collision frequency from such observations and other techniques, as well as from theoretical calculations and laboratory measurements, are invited in order to assess this key parameter in ionosphere-thermosphere coupling studies. This session will be held in memory of Roger Burnside, who pioneered some of the early studies of the thermosphere using combined radar and optical measurements.

Convenors: Richard A. Behnke, National Science Foundation, 4201 Wilson Boulevard, Arlington, VA 22230, e-mail: rbehnke@nsf.gov; and Joseph E. Salah, MIT Haystack Observatory, Route 40, Westford, MA 01886, e-mail: jsalah@mit.edu

SA03 Polar Cap Science (Joint with SM) The coupling of energy from the Sun to the Earth is strongly affected by the processes that take place in the earth's polar cap regions poleward of the auroral zone. Processes that encompass a vast domain, from the middle atmosphere to the magnetosphere and solar wind, can be observed with ground-based instruments located in the polar cap. Much of our knowledge of these processes has been derived from ground-based optical, radio wave, and magnetic measurements from the relatively sparse locations at polar cap latitudes. Papers in this session describe and discuss measurements that point out the complexity and dynamic behavior of the polar cap region and the key role that this region plays in the coupling of energy from the Sun to the atmosphere.

Conveners: John Kelly, SRI International, Menlo Park, CA 94025, tel: 415-859-3749, e-mail: kelly@sri.com; and Theodore Rosenberg, University of Maryland, College Park, MD 20742, tel: 301-314-9363, e-mail: rosenberg@uap.umd.edu

SPA: Heliospheric Physics

SH01 First Results from SOHO (Solar and Heliospheric Observatory) With the successful launch of SOHO on December 2, 1995, we are beginning a new era of solar and heliospheric observations. Invited papers in this session will describe the first results and planned observations from the 12 instruments on SOHO covering three areas of the Sun/heliosphere system: (1) the solar interior as studied through the techniques of helioseismology, (2) the solar atmosphere and studies of the heating and acceleration of the solar wind, and (3) in situ measurements at the L1 Lagrangian point of the solar wind and energetic particles. Additional contributed papers are solicited from the SOHO investigations as well as from correlated observations and relevant theory.

Conveners: Arthur I. Poland, Code 682, NASA Goddard Space Flight Center, Greenbelt, MD 20771, tel: 301-286-7076, fax: 301-286-1617, e-mail: poland@pal.gsfc.nasa.gov; Vicente Domingo, Code 682, NASA Goddard Space Flight Center, Greenbelt, MD 20771, tel: 301-286-4203, fax: 301-286-1617, e-mail: vdomingo@esa.nascom.nasa.gov; Guenter Brueckner, Code 7660, Naval Research Laboratory, Washington DC 20375, tel: 202-767-3287, fax: 202-767-5636, e-mail: brueckner@susim.nrl.navy.mil; and Alan Gabriel, Institut d'Astrophysique Spatiale (IAS), Batiment 121, Universite Paris XI, 91405 Orsay Cedex, France, tel: 33-169-85-8500, fax: 33-169-85-8675, e-mail: gabriel@iaslab.ias.fr

SH02 Coronal Heating and Solar Wind Acceleration: First Observations From Spartan 201-3 and Other Recent Developments

The fundamental problems of coronal heating and solar wind acceleration are receiving renewed interest due to a combination of observational and theoretical advances. New observations include images and spectra from the white light and UV coronagraphs flown on the Spartan 201 missions and the suite of instruments on the SOHO spacecraft; soft X ray images from Yohkoh; data from improved ground-based coronagraphs and radio scattering telescopes; and in situ measurements of solar wind plasma from the Ulysses and WIND spacecraft. In addition, new and controversial theoretical schemes are being discussed, kinetic and hybrid approaches are challenging the traditional MHD view, the likelihood that the coronal structure is more filamentary than spherically symmetrical has been raised, and simulations of plasma turbulence under coronal conditions are becoming more realistic. In this session we solicit both observational and theoretical papers bearing on these fundamental questions.

Conveners: Leonard Strachan Jr., Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS/50, Cambridge, MA 02138, tel: 617-496-7569, fax: 617-495-7455, e-mail: lstrachan@cfa.harvard.edu; William A. Coles, ECE Department, University of California at San Diego, San Diego, CA 92093-0407, tel: 619-534-2703, Fax: 619-534-2486, e-mail: coles@ece.ucsd.edu; Joseph V. Hollweg, University of New Hampshire, Morse Hall, Durham, NH 03824, tel: 603-862-3869, fax: 603-862-1915, e-mail: joe.hollweg@unh.edu; and Hugh S. Hudson, Institute for Astronomy, University of Hawaii, c/o Y. Ogawara, ISAS, 3-1-1 Yoshinodai, Sagamihara, Kanagawa, Japan 229, tel: 81-427-69-4531, Fax: 81-427-69-4532, e-mail: hudson@isass6.solar.isas.ac.jp

SH03 Advanced Visualization of Scientific Results from Space Physics, Aeronomy, and Atmospheres. (Joint with A, SA, SM)

As scientists use exponentially increasing computer power to analyze the evolutionary dynamics of complex three-dimensional global systems, they must grapple with the challenge of presenting the huge volumes of output generated by data analysis and numerical modeling in a mode that can be quickly comprehended either by their peers or by the public. Video visualization offers great promise, and the purpose of this session is to offer high-quality projection display of state-of-the-art progess across a wide range of the scientific fields spanned by the SPA and A sections. An all-day session will highlight invited examples of video presentations from the fields of atmospheric, solar, aeronomy, ionospheric, magnetospheric, and heliospheric physics. Contributed video presentations are solicited for both the oral and poster-video sessions.

Conveners: Charles C. Goodrich, Advanced Visualization Laboratory, University of Maryland, College Park, MD 20742, tel: 301-405-1516, fax: 301-405-0642, e-mail: ccg@avl.umd.edu; Gerard Van Hoven, Department of Physics, University of California at Irvine, Irvine, CA 92717, tel: 714-824-5145, fax: 714-824-5903, e-mail: VanHoven@vmsa.oac.uci.edu; Anne R. Douglass, NASA Goddard Space Flight Center, Code 916, Greenbelt, MD 20771, tel: 301-286-2337, fax: 301-286-3460, e-mail: douglass@sgccp.gsfc.nasa.gov; and Robert W. Schunk, Center Atmospheric and Space Science, UMC 4405, Utah State University, Logan, UT 84322-4405, tel: 801-797-2978, fax: 801-797-2992, e-mail: Schunk@cc.usu.edu

SH04 Corotating Interaction Regions in Three Dimensions

This session will be a follow-up to the Ulysses workshop on heliospheric corotating interaction regions (CIRs) held in March at Elmau-Castle in Germany. As spacecraft observations from inside 1AU to beyond 60AU in and out of the ecliptic have revealed, a multitude of macro- and microphenomena are associated with CIRs: solar wind plasma and waves, magnetic field structure and turbulence, suprathermal and energetic particles, interstellar pick-up ions, etc. Correlated ground-based and spacecraft observations of the Sun have identified solar source regions for the complex interactions of high- and low-speed solar wind that produce the CIRs. Theory and computer simulations have steadily increased our understanding of CIR dynamics. Invited papers will summarize the results of the Elmau Workshop, and contributed papers are solicited on all aspects of the solar/heliospheric phenomenology of CIRs.

Conveners: Horst Kunow, Institut fuer Kernphysik, Universitaet Kiel, Otto-Hahn-Platz 1, D-24118, Kiel, Germany, tel: 49-431-880-2487, fax: 49-431-85-660, e-mail: Kunow@ifkki.kernphysik.uni-Kiel.de; George M. Simnett, School of Physics and Space Research, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK, tel: 44-1-21-414-6469, fax: 44-1-21-414-3722, e-mail: gms@star.sr.bham.ac.uk; Edward J. Smith, Jet Propulsion Laboratory, MS-169-506, 4800 Oak Grove Drive, Pasadena, CA 91109, tel: 818-354-2248, fax: 818-354-8895, e-mail: JPLSP::SMITH; and Lennard A. Fisk, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143, tel: 313-747-3660, fax: 313-746-4585, e-mail: lafisk@umich.edu

SPA: Magnetospheric Physics

SM01 Kinetic Connections: Kinetic Processes of Critical Importance for Large-Scale Phenomena

Magnetospheric physics faces a singular challenge: The system's global dynamics depends on processes occurring on spatial scales and timescales extending down to the particle gyro-scale. For the foreseeable future, hydrodynamic/fluid models will remain the standard tool for global modeling, but these models break down at boundaries and singular regions where the dynamics is largely determined. Moreover, the mathematics of fluid treatments can introduce structures which are not supported in fully kinetic treatments. A reliable, predictive global model must therefore incorporate the relevant kinetic effects for each region of the magnetosphere. This session welcomes contributed papers which address this issue using observations and /or theory in any of the following areas: (1) identifying kinetic processes of importance for global dynamics; (2) distinguishing which kinetic processes are most important and where; (3) discussing descriptions and/or parameterizations of kinetic processes that allow one to incorporate their effects into a large-scale model; and (4) discussing changes to large-scale models that may be used to accommodate the effects of kinetic processes.

Conveners: B. J. Anderson, Johns Hopkins University, Applied Physics Laboratory, Johns Hopkins Road, Laurel, MD 20723-6099, e-mail: anderson@ampvx2.jhuapl.edu; S.-I. Ohtani, e-mail: ohtani@ampvx2.jhuapl.edu; and J. LaBelle, Dartmouth College, Hanover, NH 03755, e-mail: jim.labelle@dartmouth.edu

SM02 Goertz, Nicholson, Smith, and Shan: The Continuation of Their Work

This year marks five years since Chris Goertz, Dwight Nicholson, Bob Smith, and Lin-Hua Shan died at the University of Iowa. This special session is being held to remember the achievements of those colleagues and to demonstrate that their ideas and contributions continue to inspire their fellow researchers. These four AGU members influenced a broad spectrum of research areas, including auroral arcs, substorms, the plasma sheet, kinetic Alfven waves, solar wind/magnetosphere coupling, the Jovian magnetosphere, Langmuir turbulence, ionospheric modification, planetary radio emission, double layers, and the rings of Saturn. Invited talks will be presented that highlight their contributions to space physics and survey some of the subsequent progress made on their research topics. Contributed papers are hereby solicited that will discuss extensions, tests, and applications of their ideas and their work.

Conveners: Joe Borovsky, Space and Atmospheric Sciences Group, Los Alamos National Laboratory, Los Alamos, NM 87545, tel: 505-667-8368, fax: 505-665-7395, e-mail: jborovsky@lanl.gov; and Iver Cairns, Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242, tel: 319-335-0498, fax: 319-335-1753; e-mail: ihc@space.physics.uiowa.edu

SM03 ULF Waves, Observations and Theory: A Tribute to Valeria Troitskaya

Valeria Troitskaya led the field in ULF waves studies for several decades, providing sophisticated analysis of what many contemporaries considered as uninteresting "wiggles" in the data from ground-based magnetometers. Her work has come into its own as we have directly probed the magnetospheric system. ULF waves carry information on the state of the solar wind, the plasma distribution in the magnetosphere, and the level of geomagnetic activity. Siscoe, in a recent assessment of our understanding of the magnetosphere, referred to the state of models of the ULF waves in the magnetosphere as one of the triumphs of the field. Troitskaya sowed the seeds for this progress. The tribute session will showcase the current state of the field.

Conveners: Margaret G. Kivelson, Institute for Geophysics and Planetary Physics, UCLA, Los Angeles, CA 90024, tel: 310-825-3435, fax: 310-206-8042, e-mail: mkivelson@igpp.ucla.edu; and David J. Southwood, Blackett Laboratory, Imperial College, London SW7 2BZ, UK, tel: 44-71-58832-6750, fax: 44-71-8238250, e-mail: d.southwood@ic.ac.uk

SM04 Community Studies of Recent Geomagnetic Storms

Solar-terrestrial interactions associated with geomagnetic storms provide a variety of mechanisms by which energy enters into, circulates through, and dissipates in the near-Earth environment and atmosphere. Geomagnetic storms can produce significant modifications to the near-Earth environment, and therefore a major goal of current research is to understand and ultimately to predict the occurrence of storms and their effects. Recent coordinated event studies have provided a unique opportunity to examine storm-associated phenomena and to quantify their effects. In addition, the nearly continuous monitoring of the upstream solar wind by the WIND satellite, together with multiple spacecraft monitoring within the magnetosphere and ionosphere, has allowed a comparison of storm effects that have occurred under various solar and geomagnetic conditions. Papers that address storm-time energetics, large-scale storm phenomena, and coupled solar-solar wind-magnetosphere-ionosphere-atmosphere interactions are appropriate for this session. Quantitative modeling, model-data comparisons, and visualization tools are especially encouraged.

Conveners: Delores Knipp, Department of Physics, Suite 2A6 Fairchild Hall, U.S. Air Force Academy, Colorado Springs, CO, tel: 719-472-2535, fax: 719-472-3182, e-mail: knipp@ncar.ucar.edu; Terry Onsager, National Oceanic and Atmospheric Administration, Space Environment Center, 325 Broadway, Boulder, CO, tel: 303-497-5713, fax: 303-497-3645, e-mail: tonsager@sel.noaa.gov; and Nancy Crooker, Center for Space Physics, Boston University, Boston, MA 02215, tel: 508-443-8559, e-mail: crooker@buasta.bu.edu

SM05 Initial Results From Coordinated Solar-Terrestrial Data Analysis Campaigns

The international solar-terrestrial science community is moving into a new era of solar-terrestrial research as opportunities for coordinated analysis of space and ground-based data are being identified following the launch of key spacecraft such as Geotail, WIND, Polar, SOHO, Cluster, and Interball. A tremendous international coordination effort has been going on to provide a rich source of correlative data from space and ground-based measurements. These efforts have directly led to the assembly of Key Parameter and high time resolution spacecraft and ground-based databases for the IACG campaigns, GEM campaigns, and many other ISTP campaigns such as the Magnetopause Skimming campaign. This special poster session is devoted to the presentation of some of the initial results from these exciting correlative data analysis campaigns. In addition, this session will support "interactive poster" papers allowing direct access to the campaign data.

Conveners: James L. Green, NASA/GSFC, Code 630, Greenbelt, MD 20771, tel: 301-286-7354, fax: 301-286-1771, e-mail: green@nssdca.gsfc.nasa.gov; Daniel N. Baker, CU/LASP, Campus Box 590, University of Colorado, Boulder, CO 80309, tel: 303-492-4509, fax: 303-492-6444, e-mail:baker@zodiac.colorado.edu; Nelson C. Maynard, Mission Research Corp., One Tara Blvd., Ste. 302, Nashua, NH 03062, tel: 603-891-0070 ext. 248, fax: 603-891-0088, e-mail: maynard@plh.af.mil; Michael J. Teague, NASA/GSFC, Code 630, Greenbelt, MD 20771, tel: 301-286-4232, fax: 301-286-1771, e-mail: teague@nssdca.gsfc.nasa.gov; Arne Pedersen, Space Science Department of ESA, ESTEC, 2200 AG, Noordwijk, The Netherlands, tel: 31-71-5653594, fax: 31-71-5654699, e-mail: apedersen@estec.esa.nl; Trevor Sanderson, Space Science Department of ESA, ESTEC, 2200 AG, Noordwijk, The Netherlands, tel: 31-71-565-3577, fax: 31-71-565-4697, e-mail: tsanders@estec.esa.nl; and Mauricio Peredo, Hughes STX Corporation, NASA GSFC, Codes 632 and 695, Greenbelt, MD 20771, tel: 301-286-1526 and 301-441-4327, fax: 301-286-1771 and 301-441-9486, e-mail: peredo@istp1.gsfc.nasa.gov

SM06 Strategic Plan for Space Physics

In recent years the resources, conditions, and requirements to conduct research in space physics have undergone large and unexpected changes that often have conflicted with past priorities. It is time for a major reappraisal of the discipline. This session will feature a broad discussion of strategic planning for the national space physics programs for the next decade. Topics will encompass the National Academy of Sciences report "A Science Strategy for Space Physics," the most critical questions to be addressed, new mission concepts and requirements, and the development of an integrated interagency and interdisciplinary research strategy for the next decade. The program will consist of invited and contributed papers, a panel discussion, and ample opportunity for questions from the floor.

Convener: G. L. Withbroe, NASA Office of Space Science, NASA Headquarters, Washington, DC 20546, tel: 202-358-0877, e-mail: gwithbroe@gm.ossa.hq.nasa.gov

Tectonophysics

T01 Fine-Scale Hydrogeology and Geochemistry of Seafloor Hydrothermal Systems

Numerous recent studies have included precisely navigated, interdisciplinary investigations of hydrogeological and geochemical processes in areas of the seafloor where thermally driven flows modify the physical and chemical state of oceanic crust and the overlying ocean. These areas include hydrothermal sites at and near spreading centers as well as sites far from the ridge crest. These detailed studies, with measurements and sampling on a scale of meters to tens of meters or a few hundred meters, are required in many cases to map the patterns of fluid, heat, and chemical transfer and provide a consistent image of these processes. These studies also have revealed remarkable variability in the scale of processes, complexity in interactions between various scales of flow, and temporaral changes in the intensity and direction of flows. This session is intended to draw from a diverse community of scientists to present results from recent field surveys, laboratory analyses, and numerical models of seafloor hydrothermal phenomena. A combination of geological, geophysical, and geochemical observations and inferences will be used to resolve questions related to fluxes, budgets, and material properties.

Conveners: Andrew T. Fisher, Earth Sciences Department, University of California, Santa Cruz, CA 95064, tel: 408-459-5598, e-mail: afisher@earthsci.ucsc.edu; and Geoff Wheat, West Coast National Undersea Research Center, University of Alaska Fairbanks, P. O. Box 475, Moss Landing, CA 95039, tel: 408-633-7033, e-mail: wheat@mbari.org

T02 Variations in Oceanic Crustal Structure (Joint with V)

The internal structure and composition of oceanic crust vary globally as a function of spreading rate, magma supply, and other tectonic variables. Increasing geological, petrological, and geophysical evidence suggests that a significant portion of the slowly-spreading oceanic crust may be composed of serpentinized mantle peridotite rocks ("Hess" crust), especially near tectonic boundaries of seafloor spreading segments. Such "Hess" crust differs fundamentally in lithology and composition from the traditional "Penrose Conference" view of oceanic crust as layered basalt/dike/gabbro rocks that are the primary structure of fast-spreading crust. The purpose of this special session is to bring together the latest observational and theoretical studies of oceanic crust especially on the following important issues: (1) The effects of key tectonic variables such as spreading rate, magma supply, and hotspot influence on the composition and morphology of oceanic crust; (2) the interactions between spreading-center magmatic, hydrothermal, and tectonic processes that control the structure and spatial variations of "Hess" and "Penrose"-type crust along ocean ridges and within ocean basins; and (3) the extent to which "Hess" crust occurs in various ocean basins.

Conveners: Jian Lin, Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, tel: 508-289-2576, fax: 508-457-2187, e-mail: jlin@whoi.edu; and Mathilde Cannat, CNRS/Universite Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, France, tel: 33-1-44275192; fax: 33-1-44273911, e-mail: mac@ccr.jussieu.fr

T03 Topography and Land Surface Processes

This oral and accompanying poster session will focus on how the use of topographic data improves understanding of the many fluvial, aeolian, tectonic and volcanic processes that contribute to the construction, evolution, modification, and destruction of land surfaces. Invited papers will review the major remote sensing techniques through which high resolution digital topography can be obtained and major tectonic, geomorphic, hydrologic and climatic problems to which such topography can be applied. Contributed papers on any of these issues are welcome in either oral or poster format.

Convenors: Earnest Paylor, Code YSG, NASA HQ, Washington, DC 20546; tel: 202-358-0851; fax: 202-358-2770; e-mail: epaylor@mtpe.hq.nasa.gov; and Herbert Frey, Code 921, Goddard Space Flight Center, Greenbelt, MD 20771; tel: 301-286-5450; fax: 301-286-1616; e-mail: frey@denali.gsfc.nasa.gov

American Geophysical Union