SURFACE WATER COMMITTEE DRAFT SESSIONS FOR FALL 2004 1. Advances in Small Catchment Hydrology Measurement Methods Investigation of the variety of mechanisms through which small catchments transmit water and chemical fluxes has required field scientists to develop a host of prototype instruments, often by combining existing technology in innovative ways. Typically, the goals of the researcher are to develop equipment to make a measurement for which no instrument is commercially available, to modify such equipment for reliable use under field conditions or to decrease per sensor cost to increase the spatial coverage of measurement. This session focuses on the successes and failures of the measurement approaches employed by the hydrologic field research community. Conveners David Chandler, Dept. of Plants, Soils and Biometeorology, 4820 Old Main Hill, Logan, UT 84322-4820. 435-797-7326 James McNamara, Dept. of Geosciences, 1910 University Dr., Boise, ID 83725. 208-426-1354 2. Groundwater - Surface Water Interaction: Linking Disciplines The role played by groundwater - surface water interaction has been increasingly recognized as important to our understanding of physical and biogeochemical processes in the hyporheic zone, aquatic ecology, and conjunctive groundwater - surface water use. This session invites abstracts that deal with multi-disciplinary approaches to resolving field characterization and the implications of groundwater - surface water interaction, including mathematical description. Index terms: groundwater, surface water, interaction, hyporheic Conveners: Kerry T.B. MacQuarrie, Ph.D., P.Eng. Canada Research Chair in Groundwater-Surface Water Interactions Associate Professor, Department of Civil Engineering University of New Brunswick P.O. Box 4400, Fredericton New Brunswick, E3B 5A3 email: ktm@unb.ca phone: (506) 453-4521 fax: (506) 453-3568 Cathy Ryan, Ph.D., P.Geol, P.Eng Associate Professor, Department of Geology and Geophysics University of Calgary Calgary, Alberta, T2N 1N4 email: cryan@ucalgary.ca phone: (403)220-2793 fax: (403) 284-0074 1 3. Integrated Modeling for Hydrologic Decision Making and Policy Analysis Water resources managers worldwide are being faced with increasing and competing demands on a limited and more uncertain resource as populations grow, and climate varies. Proper hydrologic decision-making and policy analysis requires that all available knowledge about the physical and behavioral (social) aspects of the water resources system be brought to bear. The tightly coupled nature of the physical (hydrologic/ecological) and behavioral/economic systems, the physical constraints on availability and movement of water, and the complexities of the institutional and legal system overlays, suggest that integrated basin-scale modeling is necessary to provide decision makers with realistic assessments of the first and higher order implications of possible decisions and actions. Further, integrated models have the potential to provide assessments of uncertainty and risk. This session invites presentations on all aspects of integrated catchment management involving the use of models, the social and technical challenges involved, and lessons learned. Convenors: Hoshin Gupta (SAHRA/HWR, The University of Arizona) George Leavesley (USGS) Everett Springer (LANL) David Brookshire (UNM) David Goodrich (USDA-ARS) Vince Tidwell (SNL) 4. Hydrology and Water Resources in the Western U.S. Many of the fastest growing cities in the western U.S. are located in arid or semi-arid environments and depend on surface water originating from mountainous regions sometimes located hundreds of kilometers away. Accurate short (days to weeks), seasonal (weeks to months), and long (months to years) term forecasts of water supply from these mountainous areas is critical for water resource planning, design, and operations. This session will cover a broad range of topics related to improving water supply forecasts in the western U.S. including operational streamflow forecasting, land surface modeling and process, climate change, and the development and evaluation of spatial and temporal distribution of important hydrologic variables (e.g., precipitation, snow water equivalent, soil moisture, evaporation, transpiration, etc.). This will be advertised as a posters-only session. Conveners: Douglas P. Boyle, Department of Hydrologic Sciences, Desert Research Institute, University and Community College System of Nevada, 2215 Raggio Parkway, Reno, NV 89512-1095, dboyle@dri.edu Steven L. Markstrom, U.S. Geological Survey, Box 25046, MS 412, DFC, Denver CO 80225, markstro@usgs.gov Thomas Pagano, National Water and Climate Center, Natural Resources Conservation Services, U.S. Department of Agriculture, 101 SW Main Suite 1600, Portland, OR 97204, tpagano@wcc.nrcs.usda.gov 2 5. Observations and Modeling of Land Surface Hydrological Processes Sponsor: Hydrology CoSponsor: Atmospheric Sciences Biogeosciences Cryosphere Convener: Venkat Lakshmi University of South Carolina 701 Sumter Street, Department of Geological Sciences Columbia, SC29208USA 803 777 3552 venkat-lakshmi@sc.edu Anthony Cahill Texas A & M 3136 TAMU Department of Civil Engineering College Station, TX77843-3136USA 979-862-3858 tcahill@civilmail.tamu.edu Description: Numerous studies have resulted in observations from field experiments to study the dynamics of land surface behavior; numerical modeling of the evolution of land surface response to solar heating and precipitation; the comparison of simulations to observed quantities from field experiments; and the use of satellite remote sensing data to both drive and validate hydrological models. It is widely believed that the combination of field observations and satellite data with hydrological models through data assimilation or other procedures will produce improved estimates of hydrologic fluxes and energy budgets, soil moisture, runoff, streamflow, surface temperature, and latent, sensible ground heat, and net radiation fluxes. Abstracts on the above topics are encouraged. 6. Stream and wetlands chemical variability in time and space: measuring and modeling diel, event and seasonal scale processes Tom Torgersen, UConn George Hornberger (likely) UVirginia Joint with Biogeosciences (B), Hydrology (H) Numerous recent studies have defined hourly changes in stream chemistry due to complex biogeochemical processes in the water and the streambed. Photosynthetic O2 and CO2 variations alter pH and cause desorption of metals, photo-reduction causes metal variations, large temperature changes drive metal desorption. In wetlands, often viewed as chemical filters, diel stratification causes nutrient limitation in the surface and anoxia at depths of 1m. This is drives the exchange of metals and CO2 between the water and the sediment. On the slightly longer timescale (event and seasonal) changes in stream chemistry reflect varying sources of water (groundwater, subsurface stormflow, overland flow runoff) yield complex c-Q diagrams whose clockwise or couterclockwise rotation appears to be controlled by reaction time vs. 'soil' residence time. Such complexities are also reflected in seasonal c-Q observations. This strong temporal and spacial variation in water chemistry and flow source is critical in the interpretation of surface water flow and 3 water quality and in the net resultant downstream chemical export. This critical interaction of biogeochemistry and transport directly impacts the design, implementation and operation of surface water observatories (e.g CUAHSI). 1860, 1871, 1890, 1894, 1615, 1045, 1040, 1655, 7. Incorporating Observational Uncertainties into the Evaluation of Hydrological Models Conveners: Jim Freer Dept. of Environmental Sciences (Room A532) Lancaster University, Bailrigg Lancaster, LANCS, LA1 4YQ, UK Tel +44 (0)1524 593563 Fax +44 (0)1524 593985 Direct Computer FAX +44 (0)1524 525171 Jake Peters Contributions are invited that explore novel ways in which we directly incorporate data (e.g., site parameterization) uncertainties (both temporal and spatial) in the evaluation of hydrological models. Issues that we'd like explore in this session include but are not limited to: (a) the propagation of uncertainties in input data through hydrologic models to output forecasting uncertainties; (b) techniques for assessing the data uncertainties in comparison with model simulated output, especially those techniques that explore the use of diverse data sets some of which may be used to characterize processes over a range of effective spatial scales; (c) the formulation of 'objective functions' that reflect data uncertainties and that account for the form of the errors, where such error structures may have non-stationary properties; (d) methods that combine the above techniques and uncertainties in initial boundary conditions to more explicitly understand model structure errors; and (e) techniques for incorporating extreme events, which typically have large measurement uncertainties, in model evaluation without the introduction of large bias. Both oral and poster contributions addressing one or more of the above-mentioned issues are solicited. 4