Comparison of Groundwater Storage Changes From GRACE Satellites With Monitoring and Modeling of Major U.S. Aquifers

作者：Ashraf Rateb, Bridget R. Scanlon, Donald R. Pool, Alexander Y. Sun, Zizhan Zhang, Jianli Chen, Brian R. Clark, Claudia C. Faunt, Connor J. Haugh, Mary C. Hill, Christopher M. Hobza, Virginia L. McGuire, M. D. Reitz, Hannes Müller Schmied, Edwin H. Sutanudjaja, Sean Swenson, D. N. Wiese, Youlong Xia, W. Zell · 发表于：Water Resources Research · 年份：2020 · DOI：10.1029/2020wr027556 · 被引用次数：177 · 研究领域：Geophysics and Gravity Measurements、GNSS positioning and interference、Groundwater and Isotope Geochemistry

Abstract GRACE satellite data are widely used to estimate groundwater storage (GWS) changes in aquifers globally; however, comparisons with GW monitoring and modeling data are limited. Here we compared GWS changes from GRACE over 15 yr (2002–2017) in 14 major U.S. aquifers with groundwater‐level (GWL) monitoring data in ~23,000 wells and with regional and global hydrologic and land surface models. Results show declining GWS trends from GRACE data in the six southwestern and south‐central U.S. aquifers, totaling −90 km 3 over 15 yr, related to long‐term (5–15 yr) droughts, and exceeding Lake Mead volume by ~2.5×. GWS trends in most remaining aquifers were stable or slightly rising. GRACE‐derived GWS changes agree with GWL monitoring data in most aquifers (correlation coefficients, R = 0.52–0.95), showing that GRACE satellites capture groundwater (GW) dynamics. Regional GW models (eight models) generally show similar or greater GWS trends than those from GRACE. Large discrepancies in the Mississippi Embayment aquifer, with modeled GWS decline approximately four times that of GRACE, may reflect uncertainties in model storage parameters, stream capture, pumpage, and/or recharge rates. Global hydrologic models (2003–2014), which include GW pumping, generally overestimate GRACE GWS depletion (total: approximately −172 to −186 km 3 ) in heavily exploited aquifers in southwestern and south‐central U.S. by ~2.4× (GRACE: −74 km 3 ), underscoring needed modeling improvements relative to...