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.