Research On The Recovery Method Of Water Storage Variations And Applications Using GRACE RL06 Temporal Gravity Filed

Satellite gravity measurement is of great significance to many disciplines such as geodesy,geophysics and global hydrology.In this paper,the GRACE(Gravity Recovery and Climate Experiment)RL06 temporal gravity filed released by CSR is used to study the recovery theory of surface mass variations and the process of temporal gravity filed data processing.To realize the recovery of surface mass variations and the application of satellite gravity monitoring using temporal gravity filed in three aspects: water storage variations,hydrological loading deformation and drought-flood monitoring.The above data and theories in this thesis are used to provide new ideas for satellite gravity monitoring of water storage variations and hydrological loading deformation,a new method for calculating the features of drought index for droughtflood monitoring and assessment,and scientific decision-making basis for water resources management and surface vertical displacement monitoring.The main research work of the thesis are as follows:(1)The recovery theory of surface mass variations using temporal gravity filed is introduced in detail.The theoretical methods of gravity field expression,recovery of surface mass variations using temporal gravity filed and error evaluation of temporal gravity filed model are summarized.The basic principle of recovery of land water reserves variations and deformation of surface hydrological loads using temporal gravity filed is studied.The study shows that the quality of GRACE RL06 data is better than that of RL05 in both the recovery results of water storage variations and the errors of the quantitative evaluation model.(2)The data processing flow of temporal gravity filed and the joint analysis method of multi-source data are systematically summarized.The process of temporal gravity filed data processing and the post-processing algorithm are analyzed.The joint analysis methods of temporal gravity filed,GPS data and hydrological model are discussed.The effects of unified reference frame(geocentric correction)and high frequency non-tidal effects of atmosphere and ocean(GAC correction)on the recovery of hydrological loading deformation using temporal gravity filed are analyzed.The research shows that the combined filtering can significantly improve the extraction accuracy of temporal gravity signals.GAC correction has different effects on different reference stations in terms of amplitude and phase in China.(3)Satellite gravity monitoring and analysis of water storage variations in Yunnan-Guizhou Plateau are realized by using GRACE temporal gravity filed and GLDAS(Global Land Data Assimilation System)hydrological model.The long-term trend and seasonal characteristics of land water storage variations and groundwater storage variations in Yunnan-Guizhou Plateau from 2003 to the end of 2010 were studied,and the drought events in the research time domain were detected and analyzed.The GRACE signal leakage error and C20 error are compared,and the time series characteristics of water storage variations in Yunnan-Guizhou Plateau are studied by correlation analysis,trend analysis and Lomb-Scargle time-frequency analysis.The global probability weighting and quartile numerical method are proposed to extract the changes of groundwater storage variations,and the differences between latitude cosine weighting and the above two water storage variations extraction algorithms are compared.The study shows that the GRACE temporal gravity filed can monitor and analyze the variations of regional water storage.The attenuation and leakage of temporal gravity filed signals can be effectively suppressed by using the scale factor method.The groundwater storage variations extracted by the three methods are basically the same,among which the quartile numerical method has the least amount of calculation.(4)The satellite gravity monitoring and analysis of vertical hydrological loading deformation in North China Plain are realized by using GRACE temporal gravity filed and GPS time series.The effects of geocentric correction and GAC correction on the vertical hydrological loading deformation time series of GRACE recovery in North China Plain from 2002 to 2016 are quantitatively evaluated.The time series characteristics and correlation between GRACE vertical hydrological loading deformation and GPS vertical displacement are studied,and the spatial-temporal features of vertical hydrological loading deformation in North China Plain are analyzed.The study shows that the monitoring and analysis of vertical hydrological loading deformation can be realized by GRACE temporal gravity filed.The influence of GAC correction on the time series of GRACE displacement in North China Plain is about ±8mm,while the influence of geocentric correction is relatively weak.There is a high correlation between GRACE and GPS displacement time series.(5)The GRACE_DSI06 drought index is calculated by using the temporal gravity filed to analyze the spatial-temporal features of drought and flood in China.The annual eigenvalue algorithm of drought index weighted by linear fitting residual and the grid eigenvalue algorithm weighted by plane fitting residual are proposed.The overall drought and flood pattern in China is comprehensively analyzed through the proposed drought index eigenvalue calculation method combined with GRACE_DSI06,PDSI,SPI and SPEI.The characteristics of drought and flood in Sichuan and Xinjiang provinces and the possible causes of the characteristics in the region are deeply analyzed.The research shows that the monitoring and analysis of the spatial-temporal features of drought and flood can be realized by GRACE_DSI06.The proposed method for calculating the eigenvalues of drought index can effectively monitor drought and flood events and their spatial distribution features in Sichuan and Xinjiang.There are 67 figures,16 tables,110 references in this thesis.