Abstract:

The traverse route from Zhongshan Station to Dome A on the Antarctic ice sheet is an ideal area to study the water-stable isotopic composition of surface snow. Analyzing spatial distribution and impact factors of water-stable isotopes along this section is of significance in reflecting the material source and climate change in the East Antarctic ice sheet. This paper discusses the synthetic effect of different environmental factors based on linear regression and correlation analyses. The results indicated that geographical factors and temperature have a significant correlation with δ18O and δD, and both indexes show a tendency to decrease as elevations rise: the most important geographical factor. We also discovered that the δ-T slope varies in offshore and inland areas by comparing these with other sections. These variations are caused by changes in moisture source conditions and the action of the kinetic fractionation effect in a low-temperature, supersaturated environment. The spatial distribution of excess deuterium differs between the coastal and inland areas, leading to speculation that moisture source conditions, as well as temperature, are key factors.

Key words: the traverse route from Zhongshan Station to Dome A, surface snow, stable isotope, impact factors, spatial distribution