HR: 10:20h
AN: H32A-01 INVITED    [Abstracts]
TI: On Streamflow and Water Balance Modeling at Regional and Aquifer Scales: Validation of Remotely Sensed Radar Precipitation Through Continuous Simulation
AU: * Vieux, B E
EM: bvieux@ou.edu
AF: University of Oklahoma, School of Civil Engineering and Environmental Science, Natural Hazards and Disaster Research, National Weather Center 120 David L. Boren Blvd., Suite 3600, Norman, OK 73072, United States
AU: Moreno, M A
EM: maria@ou.edu
AF: University of Oklahoma, School of Civil Engineering and Environmental Science, Natural Hazards and Disaster Research, National Weather Center 120 David L. Boren Blvd., Suite 3600, Norman, OK 73072, United States
AU: Looper, J P
EM: looperjp@ou.edu
AF: University of Oklahoma, School of Civil Engineering and Environmental Science, Natural Hazards and Disaster Research, National Weather Center 120 David L. Boren Blvd., Suite 3600, Norman, OK 73072, United States
AB: The hydrologic water balance, governing the amount of water that an aquifer receives, is important for estimating the amount of water that can be safely extracted without diminishing the water resources of a region. The change in storage of water in a stream-aquifer system for a specific time period is affected by precipitation, surface runoff, ground water recharge/discharge/pumping, evaporation, and transpiration. Sufficiently accurate and detailed precipitation measurements are needed over regional, river basin, and aquifer recharge areas. The accuracy and spatial sampling density of rainfall observation systems affect the accuracy of hydrologic predictions, and can be a major limitation to understanding the water fluxes across surface and subsurface boundaries. The study area includes the Arbuckle-Simpson aquifer located in South Central Oklahoma and underlies an approximate area of 1295 km2. The Arbuckle-Simpson aquifer provides water to streams and rivers as baseflow, including the 1200 km² Blue River. This study is motivated by research concerning recharge and the hydrologic water balance over the Arbuckle- Simpson aquifer region. The objective of this study is to identify components of the hydrologic water balance, especially streamflow and recharge. The influence of spatially and temporally variable precipitation on the surface runoff, and uncertainty associated with radar and gauge sensor systems is evaluated over a period of fourteen years at hourly timesteps within a distributed hydrologic modeling context. To accomplish this objective, a distributed hydrologic model of the surface drainage systems including the Blue River, and components of the Arbuckle-Simpson aquifer recharge area are simulated using spatially variable rainfall derived from three rainfall products: 1) Gauge only products derived from surrounding Mesonet gauges, 2) National Weather Service Stage III/MPE radar rainfall (ABRFC) with no adjustment or quality control, and 3) Mean Field Bias adjustment of the ABRFC product with Mesonet gauges and gap filling. Validation of these rainfall products using observed streamflow is assessed through continuous simulation of direct runoff. The uncertainty and accuracy of streamflow within a distributed modeling context is accomplished using Vflo setup at various resolutions including 200- and 500-m grids over an area of 1590 km², and 13240 km², respectively. Precipitation derived from rain gauge is consistent with radar estimation at annual timescales, however, significant differences in streamflow simulated with these products result.
DE: 1821 Floods
DE: 1847 Modeling
DE: 1853 Precipitation-radar
DE: 1860 Streamflow
DE: 1874 Ungaged basins
SC: Hydrology [H]
MN: 2007 Fall Meeting