Observed sustained decrease in surface mass balance in inland East Antarctica in 2005-2020

Field observations for this study were conducted along the Chinese National Antarctica Research Expedition (CHINARE) inland Antarctic travers route, which stretches 1248 km from coastal Zhongshan Station (ZS, 69.37oS, 76.37oE) in the Indian Ocean sector to Dome A (80.37oS, 77.35oE), the summit of the East Antarctica Ice Sheet. This transect is situated approximately at longitude 77°E. Since 2005, surface snow accumulation rates have been measured by placing bamboo stakes every 2 km along the transect. We collected interannual surface accumulation rate data for the period 2005-2020. The relative changes in snow surface height were determined through repeated measurements of the height between the top of the bamboo stakes and the snow surface. From CHINARE-21 in 2004 to CHINARE-36 in 2020, approximately 600 SMB stakes were measured annually along the traverse, and this approach yielded a dataset of the surface snow accumulation rates spanning 15 years.