The invention relates to the field of
satellite gravity detection and application, in particular to a method for inverting
groundwater reserves by combining GNSS, GRACE and InSAR technologies, which comprises the following steps: acquiring GNSS
vertical displacement data, GRACE equivalent water height data and InSAR vertical deformation rate data; the GNSS
vertical displacement data, the GRACE equivalent water height data and the InSAR vertical deformation rate data are associated to the total water reserve change, and a joint inversion equation set is constructed; the uncertainty of GNSS, InSAR and GRACE observation trends is quantified, weight coefficients corresponding to GNSS
vertical displacement data, GRACE equivalent water height data and InSAR vertical deformation rate data are determined, and
observation data vectors are constructed; laplacian roughness constraint is introduced, a joint inversion equation set is solved through step-by-step iterative calculation according to a weighted least square method by observing data vectors, and high-resolution
groundwater reserve changes are determined. By combining GNSS, GRACE and InSAR technologies, the limitation of a traditional single technology is overcome,
advantage complementation of multi-
source data is realized, and the accuracy of underground water reserve inversion is remarkably improved.