Seasonal and Interannual Fluctuations of Glacier Mass Balance and Climate Response Processes on the Tibetan Plateau Based on GRACE/GRACE-FO

Abstract

Glacier mass changes in high mountainous areas are in an unbalanced status due to global climate warming. In this study, we use the Gravity Recovery and Climate Experiment as well as its Follow-on mission (GRACE/GRACE-FO) data to constrain the spatiotemporal variations of glacier mass in the high mountain of Tibetan Plateau (TP) during 2002 and 2020. The total glacier mass balance shows a descending trend over the TP and its surroundings with an overall melting rate of ~21 Gt/yr in the past two-decades. The significant glacier mass loss of spatial pattern is mainly concentrated in the periphery of the TP, such as the Himalayas, Hindu Kush and Tianshan, while the Kunlun Mountains demonstrates an increasing trend of glacier mass balance. The annual variation of glaciers in 22 sub-regions shows significant spatial differences in the amplitudes and phases, which is the direct feedback of regional climate change. In addition, based on the wavelet spectrum analysis, we find that the abnormal glacier mass changes correlate well with the interannual oscillations of precipitation and temperature. This corresponds to the extreme climate events, such as 2010-2012 La Niña event and 2015-2016 El Niño event. All these results validate the climate process in response to the interannual variation of glaciers on the TP, thus is of great significance to the study of systematic balance of regional water cycle.