HR: 0800h
AN: H31A-0125    [Abstracts]
TI: Comparison of Terrestrial Water Storage Variations from GRACE With In-Situ Soil Moisture and Groundwater Level Measurements in Semiarid Irrigated Systems: Case Study High Plains Aquifer, USA
AU: * Strassberg, G
EM: gil.strassberg@beg.utexas.edu
AF: Bureau of Economic Geology, Jackson School of Geosciences, University of Texas at Austin, Univ. of Texas at Austin J.J. Pickle Research Campus, Bldg. 130 10100 Burnet Rd., Austin, TX 78758-4445, United States
AU: Scanlon, B R
EM: bridget.scanlon@beg.utexas.edu
AF: Bureau of Economic Geology, Jackson School of Geosciences, University of Texas at Austin, Univ. of Texas at Austin J.J. Pickle Research Campus, Bldg. 130 10100 Burnet Rd., Austin, TX 78758-4445, United States
AU: Chambers, D
EM: chambers@csr.utexas.edu
AF: Center for Space Research, University of Texas at Austin, 3925 W. Braker Lane #200, Austin, TX 78759-5321, United States
AB: Depletion of groundwater storage in semiarid regions as a result of intensive irrigation is a critical water resource issue. Many of these systems are poorly monitored, such as the North China Plain and western India. The objective of this study was to evaluate the ability of the Gravity Recovery and Climate Experiment (GRACE) to quantify changes in groundwater storage using detailed monitoring records available for the High Plains aquifer (450,000 km² area). This study presents a comparison of terrestrial water storage changes derived from GRACE gravity measurements between 2003 and 2006 with in-situ soil moisture and groundwater level measurements covering the High Plains aquifer. Soil moisture measurements from 80 shallow (~1 m depth) mesonet stations from Texas, Oklahoma, and Nebraska, were combined with data from deeper (up to 7 m) monitoring sites to estimate temporal and spatial variations in soil moisture over the High Plains. Anomalies in soil moisture were compared with soil moisture changes simulated by the Noah Land surface model. Groundwater storage variations over the aquifer were estimated by assimilating groundwater level measurements from multiple state and federal agencies. Good correspondence between soil moisture storage from the ground based networks and the Noah land surface model increased confidence in the soil moisture storage variations. Terrestrial water storage (TWS) changes from GRACE compared favorably with TWS (approximated as changes in soil moisture + groundwater storage) from the monitoring networks. Results from this study demonstrate the potential for the GRACE satellites to monitor water storage variations in semiarid irrigated systems, where mining of groundwater resources is a critical issue.
DE: 1218 Mass balance (0762, 1223, 1631, 1836, 1843, 3010, 3322, 4532)
DE: 1640 Remote sensing (1855)
DE: 1895 Instruments and techniques: monitoring
SC: Hydrology [H]
MN: 2007 Fall Meeting