Understanding the impact of climatic variability on terrestrial water storage in the Qinghai-Tibet Plateau of China

Abstract

ABSTRACT Monitoring terrestrial water storage anomalies (TWSA) is essential for better understanding the influences of climatic variability on hydrological cycles. Here we use Gravity Recovery and Climate Experiment (GRACE)/GRACE Follow-on satellite data and meteorological observations to analyse the inter-annual trends of TWSA across the Qinghai-Tibet Plateau (QTP) during 2003–2020 and investigate the relationships between climatic variability and annual changes in TWSA. Results indicate that TWSA across the QTP generally decreased, at a rate of −0.5 ± 1.4 mm/year during 2003–2020, which mainly arises from the coupled effects of Potential evapotranspiration (PET) and precipitation. In terms of the effects of climatic variability, annual changes in TWSA show a negative correlation coefficient (r = −0.76) with PET, which is greater than that with precipitation (r = 0.67). The cross-wavelet transformation analysis revealed that the evolution of TWSA across the QTP is closely associated with the Atlantic Multidecadal Oscillation. Our conclusions can help decision makers to formulate appropriate policies for the assessment and management of water resources over the QTP.