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The Total Water Storage Anomaly (TWSA) comprises all the water components on the Earth's continental areas and is the only variable that allows for comprehensively closing the terrestrial water budget, balancing precipitation, evapotranspiration, and runoff. Also, the TWSA is served as an important indicator of global climate change (Kusche et al., 2016).Since 2002, the Gravity Recovery and Climate Experiment (GRACE) satellites have measured the global total water storage anomalies with an unprecedented accuracy (Wahr et al., 2004). However, no effective measures could be used to monitor the global TWSA prior to the GRACE era (i.e., before 2002) and during the gap period (i.e., 2017-2018) of the GRACE and GRACE Follow-On (GRACE-FO) missions. Before the launch of GRACE, TWSA would have to be computed by aggregating storage changes simulated by hydrological models (Nie et al., 2019), possibly combined with in-situ gauge measurements of surface water levels or groundwater head (Seneviratne et al., 2004;Van Dijk et al., 2016;Chen et al., 2019). However, hydrological models rely on possibly biased forcing data, miss important process representations (e.g.,

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The Global Positioning System (GPS) records monsoonal precipitable water vapor (PWV) and vertical crustal displacement (VCD) due to hydrological loading, and can thus be applied jointly to diagnose meteorological and hydrological droughts. We have analyzed the PWV and VCD observations during 2007.0–2015.0 at 26 continuous GPS stations located in Yunnan province, China. We also obtained equivalent water height (EWH) derived from the Gravity Recovery And Climate Experiment (GRACE) and precipitation at these stations with the same period. Then, we quantified the annual variations of PWV, precipitation, EWH and VCD and provided empirical relationships between them. We found that GPS-derived PWV and VCD (positive means downward movement) are in phase with precipitation and GRACE-derived EWH, respectively. The annual signals of VCD and PWV show linearly correlated amplitudes and a two-month phase lag. Furthermore, the results indicate that PWV and VCD anomalies can also be used to explore drought, such as the heavy drought during winter/spring 2010. Our analysis results verify the capability of GPS to monitor monsoon variations and drought in Yunnan and show that a more comprehensive understanding of the characteristics of regional monsoon and drought can be achieved by integrating GPS-derived PWV and VCD with precipitation and GRACE-derived EWH.