Analysis of glacier changes in the Nyainqentanglha Mountain based on the combination of satellite gravity and optical remote sensing

The GRACE and GRACE-FO gravity satellite data were used to retrieve the glacier quality changes in the Nyainqentanglha Mountains from August 2002 to April 2020, and combined with remote sensing technology to estimate the glacier area and reserves changes in the western Nyainqentanglha. The main conclusions are as follows:①The glaciers in the Nyainqentanglha Mountains showed an overall retreat trend during the study period, and there was an accelerated melting trend after 2013. ②The correlation between temperature changes and glacier melting curves can be found by comparing with summer temperature changes and precipitation anomalies better, the precipitation continued to decrease during the study period, indicating that the increase in temperature and the decrease in precipitation are the main reasons for the continuous decrease in the mass of glaciers in the Nyainqentanglha. ③The glacier area of the West Nyainqentanglha Mountains decreased by 72.30 km2 from 2003 to 2017, with an average annual decrease rate of 5.16 km2/a. The glacier area retreats most obviously in the altitude range of 5600~5800 m. ④The coordinated application of satellite gravity and optical remote sensing technology can complement each other's advantages. It can not only estimate changes in glacier quality, but also detect changes in glacier area and elevation. At present, there are still some shortcomings in the joint application of the two technologies, which need to be further studied.