Stable isotope ratios (δ18O and δD) in Antarctic snow and ice are basic proxy indices of climate in ice core studies. The relation between the ratios has important indicative significance for moisture sources. In general, the fractionation characteristics of the two isotopes vary with different meteorological and topographical conditions. This paper presents the spatial and temporal distribution of meteoric water line (MWL) slopes along a traverse from the Zhongshan Station (ZSS) to Dome A in East Antarctica. It is found that the slopes decrease with the increasing distance inland from the coast and the lowest slope occurred at Dome A, where the long-range transported moisture dominates and clear sky snowing have an influence. The slopes in different layers of the snowpack showed a decreasing trend with depth and this is attributed to the fractionation during the interstitial sublimation and re-condensation processes of the water vapor. Frost flower development on the interior plateau surface can greatly alter the depth evolution of the MWL slope. The coastal snow pits also go through the post-depositional smoothing effect, but their influences are not so significant as the inland regions.

中文翻译：

---

东南极雪中稳定同位素分馏的时空变化

稳定同位素比率 (δ18南极冰雪中的 O 和 δD) 是冰芯研究中气候的基本代理指标。比率之间的关系对于水分来源具有重要的指示意义。一般来说，这两种同位素的分馏特征随着气象和地形条件的不同而不同。本文介绍了南极东部中山站 (ZSS) 至 Dome A 导线沿线的大气水线 (MWL) 斜坡的时空分布。研究发现，随着内陆离海岸距离的增加，坡度减小，坡度最低出现在圆顶A，远距离输送的水分占主导地位，晴空降雪有影响。积雪不同层的坡度随深度呈递减趋势，这归因于水汽在间隙升华和再冷凝过程中的分馏。高原内部地表的霜花发育可以极大地改变MWL斜坡的深度演化。沿海雪坑也经历沉积后平滑效应，但其影响不如内陆地区显着。