The Challenge of Spatial Resolutions for GRACE-Based Estimates Volume Changes of Larger Man-Made Lake: The Case of China's Three Gorges Reservoir in the Yangtze River
The Challenge of Spatial Resolutions for GRACE-Based Estimates Volume Changes of Larger Man-Made Lake: The Case of China's Three Gorges Reservoir in the Yangtze River
复制标题
DOI：
10.3390/rs11010099
复制
发表时间：
2019-01
期刊：
影响因子：
--
通讯作者：
Linsong Wang;M. Kaban;Maik Thomas;Chao Chen;Xian Ma
中科院分区：
文献类型：
--
作者：
Linsong Wang;M. Kaban;Maik Thomas;Chao Chen;Xian Ma
三峡水库是世界上最大的水库，蓄水量巨大，对地球重力场的影响可能从亚季节到年际尺度。重力恢复和气候实验（GRACE）使命提供的卫星数据可能会探测到总水储存量（TWS）的显著变化。为了检测这些存储水的变化，其他因素的影响，首先从这些数据中删除，由于近地表质量变化的GRACE有限的代表。在这里，我们评估了目前流行的陆面模型（LSMs）的基础上，在现场测量，发现WaterGAP全球水文模型（WGHM）表现出较高的相关性比其他分析模型与现场降雨测量。然后，我们使用WGHM的输出，以消除气候引起的TWS的变化，如地表水存储，土壤，冠层，雪，和地下水存储。残差结果（GRACE减去WGHM）显示出强烈的趋势（3.85 ± 2 km 3/yr），明显高于基于现场水位测量的TGR分析和后推实验（2.29 ± 1 km 3/yr）。我们还估计了渗流响应TGR填充，其他人为水坝的贡献，并使用原位重力和GPS观测，以评估主要因素的GRACE为基础的高估TGR体积变化。我们发现，通过粗粒材料模拟的渗透率变化解释了基于GRACE的TGR体积变化估计与原位测量之间的大部分差异，但与原位重力观测的一致性要低得多。相比之下，13个相邻水库的渗漏贡献解释了GRACE和WGHM得出的TGR体积变化的约74%。我们的研究结果表明，GRACE的高估TGR质量变化主要来自周围的人工水库的贡献和低估TWS的变化WGHM模拟由于WGHM在地下水成分的大的不确定性。此外，该研究还表明，当GRACE数据与相关的补充观测相结合时，可以可靠地从水库或湖泊体积变化中得出。
The Three Gorges Reservoir (TGR) in China, with the largest dam in the world, stores a large volume of water and may influence the Earth’s gravity field on sub-seasonal to interannual timescales. Significant changes of the total water storage (TWS) might be detectable by satellite-based data provided by the Gravity Recovery and Climate Experiment (GRACE) mission. To detect these store water changes, effects of other factors are to be removed first from these data due to band-limited representation of near-surface mass changes from GRACE. Here, we evaluated three current popular land surface models (LSMs) basing on in situ measurements and found that the WaterGAP Global Hydrology Model (WGHM) demonstrates higher correlation than other analyzed models with the in-situ rainfall measurement. Then we used the WGHM outputs to remove climate-induced TWS changes, such as surface water storage, soil, canopy, snow, and groundwater storage. The residual results (GRACE minus WGHM) indicated a strong trend (3.85 ± 2 km3/yr) that is significantly higher than the TGR analysis and hindcast experiments (2.29 ± 1 km3/yr) based on in-situ water level measurements. We also estimated the seepage response to the TGR filling, contributions from other anthropogenic dams, and used in-situ gravity and GPS observations to evaluate dominant factors responsible for the GRACE-based overestimate of the TGR volume change. We found that the modeled seepage variability through coarse-grained materials explained most of the difference between the GRACE based estimate of TGR volume changes and in situ measurements, but the agreement with in-situ gravity observations is considerably lower. In contrast, the leakage contribution from 13 adjacent reservoirs explained ~74% of the TGR volume change derived from GRACE and WGHM. Our results demonstrate that GRACE-based overestimate TGR mass change mainly from the contribution of surrounding artificial reservoirs and underestimated TWS variations in WGHM simulations due to the large uncertainty of WGHM in groundwater component. In additional, this study also indicates that reservoir or lake volume changes can be reliably derived from GRACE data when they are used in combination with relevant complementary observations.