地下水模拟是区域地下水管理的重要工具，然而有效的模型需要大量地下水监测和水文地质信息支撑。地下水监测点多位于城市人口集中区而且分布不均，系统的地下水监测投资和维护成本大，而月尺度的GRACE卫星数据可免费下载，已经在跟踪区域地下水储量变化方面显示出巨大潜力。GRACE Follow-On卫星将比GRACE卫星的分辨率至少提高10倍。基于此，本项目拟采用重力梯度、缔合勒让德函数、参数自动估计、统计分析和数值模拟等方法，研究GRACE和GRACE Follow-On卫星数据同化的关键技术，探索卫星估算区域水文地质参数方法及其有效性、反演的区地下水储量信息代表性以及如何约束水文地质参数、甄别地下水补给和排泄条件等关键问题，最终发展融合卫星面数据的地下水模型，并进行案例研究。成果将提高区域地下水模型的仿真性，为有效管理区域地下水和缓解地下水利用与环境之间的矛盾提供技术支持。

Groundwater modeling is an important tool of regional groundwater resources management. However, effective models need massive groundwater observation data and hydrogeology parameters. Groundwater observation wells are often located on inhabited area, and distributed non-uniformly. Sysmatic groundwater monitoring network requires a lot of investment and maintance. But monthly GRACE satellite data is freely available and has showed great potential in tracking groundwater changes. GRACE Follow-On data will have at least ten times tempo-spatial resolution than GRACE data does. Based on the fundamental problems, the project will integrate a series of methods, such as the Gravity Gradient Method, the associated Legendre polynomials, parameter automatic estimation, statistical analysis and numerical simulation. The research will try to carry out studies on method of remote sensing data assimilation, including the method and its applicability of estimating regional hydrogeology parameters, the representativeness of regional groundwater storage anomalies, how to constrain the hydrologeology parameters, and further identify the recharge and discharges. Finnaly goundwater models will be developed with integrated point-based observation data and regional data obtained from GRACE and GRACE Follow-on satellites. The developed model will be applied to case studies. The results will greatly improve the accuracy of groundwater models, and will provide technical support of regional groundwater management and relieve the conflicts among groundwater and environment.