采用点质量模型方法反演中国大陆及周边地区陆地水储量变化

研究了反演区域陆地水储量变化的点质量模型方法，采用Tikhonov正则化方法解决了反演过程中参数估计病态问题。利用GRACE（gravity recovery and climate experiment）时变重力场模型数据，用点质量模型方法反演了中国大陆及其周边地区陆地水储量变化，将点质量模型反演结果与球谐系数法反演结果、GLDAS（global land data assimilation）水文模型数据进行了验证分析，并选取了4个特征点计算了陆地水储量变化时间序列。实验结果表明，由于点质量模型方法将研究区域内不同网格质量变化对地球重力场的影响分离开来，所得区域陆地水储量变化局部信号更明显，并且点质量模型方法反演结果与GLDAS水文模型数据相关性更强。

Recovery Water Storage Variation in China and Its Adjacent Area by Method of Point-Mass Model

Method of point-mass model is investigated thoroughly. The ill-posed problem in parameter estimation is solved by Tikhonov regularization. Water storage variation in China and adjacent is recovered by method of point-mass model using GRACE time-variable gravity field data. The inversion result is verified by GLDAS hydrological model data and method of spheric harmonic coefficient. Meanwhile the water storage variation series of 4 characteristic points are calculated. The results show that because of the separated influence of different region mass anomaly on gravity field, the signal of water storage variation in local area which is recovered by method point-mass model is more powerful. By comparing the water storage variation series of 4 characteristic points, it is concluded that the correlation between the recovery results by method of point-mass model and GLDAS hydrological model data is stronger.