12月28日（周三）学术报告通知
报告题目：GRACE Detection of Water Storage Changes in the Three Gorges Reservoir and comparison with in situ measurements.
报告专家：王先伟 中山大学副教授
报告时间：12月28日（周三）中午1点30分
报告场所：遥感学院附三2楼多功能报告厅
Abstract
Water impoundment in the Three Gorges Reservoir (TGR) of China caused a large mass redistribution from the oceans to a concentrated land area in a short time period. We show that this mass shift is captured by the Gravity Recovery And Climate Experiment (GRACE) unconstrained global solutions at a 400-km spatial resolution after removing correlated errors. The WaterGAP Global Hydrology Model (WGHM) is selected to isolate the TGR contribution from regional water storage changes. For the first time, this study compares the GRACE (minus WGHM)-estimated TGR volume changes with in situ measurements from April 2002 to May 2010 at a monthly time-scale. During the 8-year study period, GRACE-WGHM estimated TGR volume changes show an increasing trend consistent with the TGR in situ measurements, and lead to similar estimates of impounded water volume. GRACE-WGHM estimated total volume increase agrees to within 14% (3.2 km3) of the in situ measurements. This indicates that GRACE can retrieve the true amplitudes of large surface water storage changes in a concentrated area that is much smaller than the spatial resolution of its global harmonic solutions. The GRACE-WGHM estimated TGR monthly volume changes explain 76% (r2 =0.76) of in situ measurement monthly variability and have an uncertainty of 4.62 km3. Our results also indicate reservoir leakage and groundwater recharge due to TGR filling and contamination from neighboring lakes are non-negligible in the GRACE total water storage changes. Moreover, GRACE observations could provide a relatively accurate estimate of global water volume withheld by newly constructed large reservoirs and their impacts on global sea level rise since 2002.
In the beginning of the presentation, he will give a short introduction to his recent other studies.
报告专家介绍：
http://gp.sysu.edu.cn/gpsite/teacher/snews.asp?typeid=0901&userSN=126
