Présentations Colloques

Oral Presentation
Session 8.11: Hydrogeodesy: new surface tools to characterize and monitor active and managed groundwater systems
Scanlon Bridget R.
Application of a New GRACE Product for Assessing Long-term Trends in Water Storage in Aquifers Globally
There is increasing interest in application of the Gravity Recovery and Climate Experiment (GRACE) satellite data to assess changes in groundwater storage in aquifers globally. Here we describe a new GRACE Mascons (mass concentration) product to evaluate trends in total water storage (TWS) and groundwater storage (GWS) in combination with other land surface model output for Jan 2003 through Dec 2014 in aquifers globally. The new mascons product was developed by the Univ. of Texas Center for Space Research (CSR-M) with an equal area grid (120 km spacing between grid cells). The CSR-M product applies constraints related to the distribution of land and ocean and eliminates north-south stripes. GRACE processing for CSR-M relies entirely on GRACE data and does not use other models, such as land surface models, to constrain the data. This product represents a significant advance over traditional GRACE spherical harmonic products by increasing user friendly applications with no post processing requirements. We will provide examples of the application of the CSR-M processing to aquifers in different regions globally. Examples of aquifers include the High Plains and Central Valley aquifers in the U.S. subjected to drought and intensive irrigation. Depletion and recovery in aquifer storage in the Murray Darling Basin related to drought and floods will also be described. Irrigation impacts on groundwater storage in north-west India and the North China Plain will be shown. GRACE data processing is continually improving and becoming more user friendly for hydrogeologists to apply to different regions.
United States