Summer surface temperature change of Greenland Ice Sheet from 2000 to 2020 and its effect on mass balance

Abstract

The monitoring of the Greenland Ice Sheet is of great significance to global and Arctic climate change. As the largest Ice Sheet in the Northern Hemisphere, the Greenland Ice Sheet is critical to the climate response and has always been the focus of global attention. Based on the MODIS temperature product data, this paper analyzes the interannual trend of the Greenland Ice Sheet summer surface temperature and surface melting range from 2000 to 2020. The effect of surface temperature on the mass balance of the Greenland Ice Sheet is analyzed with IMBIE data, and the effect of atmospheric circulation on the surface temperature of the Greenland Ice Sheet is discussed. The results show that the trend of summer surface temperature and melting range of the Greenland Ice Sheet is consistent, showing a positive upward trend from 2000 to 2012, reaching a peak in 2012, and then showing a downward trend of fluctuation. The northern part of the Greenland Ice Sheet had the highest rate of warming during the study period, more than twice as fast as any other region, the south-east and southwest had the highest temperatures but the lowest growth rates；And there was a strong correlation between the Greenland Ice Sheet's summer surface temperature, the extent of melting, and the mass balance, at the same time, an increase of 1 °C in the summer surface temperature of the Greenland Ice Sheet will lead to an increase of 74. 29 Gt·a-1 in mass loss. Finally, the NAO（North Atlantic Oscillation）and GBI（Greenland blocking index）indices are analyzed, the influence of GBI on the surface temperature of Greenland Ice Sheet in summer is stronger than that of NAO. Greenland Ice Sheet surface temperature is negatively correlated with NAO （r=-0. 64, P<0. 05）and positively correlated with GBI（r=0. 77, P<0. 05）.