Submitted to: Geological Society of America Meeting
Publication Type: Abstract Only
Publication Acceptance Date: March 25, 1996
Publication Date: N/A
Technical Abstract: The Little Washita River Watershed (LWRW) is the largest (230 sq. mi.) of the USDA-Agricultural Research Service's watersheds and one of the world's best instrumented watersheds. Established in the 1930s, it was used to demonstrate the effectiveness of soil erosion control, soil and water conservation structures, and floodwater retarding reservoirs. A government initiative on global change led to a major reinstrumentation effort on the LWRW beginning in the late 1980's. This involved upgrading a network of 42 meteorological stations on a 5 km x 5 km grid to provide automated monitoring of air temperature, relative humidity, incoming solar radiation and soil temperature at four depths. Soil moisture is also monitored at selected sites. Four "nested" stream gages monitor stream flow. The LWRW is strategically located to other large-scale projects including GCIP-GEWEX, DOE's CART/ARM, the OK Mesonet System, and within the coverage of four operational weather surveillance radars (WSR-88D). In 1992 and 1994, cooperative, multi-agency experiments were conducted to collect remotely- sensed data for hydrologic investigations. Remotely-sensed data from hand- held instruments, airborne sensors on NASA aircraft and space shuttle, Endeavour, were collected. Future instrumentation includes infrared thermometer transducer for measuring surface/canopy temperature, net radiometers and pyrgeometers, automated soil moisture sensors, and weighing lysimeters. An extensive groundwater well network is also planned. Instrumentation will provide data for investigation of scaling and spatial/temporal variability of water and energy fluxes, percolation, interflow, as well as for watershed parameterization, and hydrologic modelling at the mesoscale.