Noble Gases and Helium Isotopes During Ocean2ice: Processes and Variability of Ocean Heat Transport Toward Ice Shelves in the Amundsen Sea

冰架质量平衡受净表面增生（降水减去消融和表面融化项）、沿冰架空腔底部的崩解和基底融化所控制，这些空腔与变暖的海洋接触。估算基底融化速率是这一平衡中最具挑战性的一项，因为它很难直接观测，而且对海洋温度和其他海洋-大气过程（如海冰循环）的变化也很敏感。该项目将加入Ocean2ice计划，该计划由英国领导，旨在整合最先进的仪器，化学分析和建模，以改善南极环流模式中冰架平衡过程的动态表示。在阿蒙森海，浅水暖环极深水（CDW）和浅层冰川融水是冰架质量平衡的两个重要诊断和预报项。通过测量这些水质量的分布，使用一套独特的惰性气体示踪剂？3He、4He、Ne、Ar、Kr和Xe -以及它们随时间的变化，将估算南极西部一些大型冰架（如松岛冰川）的基本融化速率。格陵兰岛和南极西部冰盖加起来可能使平均（全球）海面高度增加10米以上。冰川动员速率可能增加多快具有相当大的社会重要性。

Ice shelf mass balance is controlled by net surface accretion (precipitation minus ablation and surface melt terms), calving and basal melt along the underside of the ice shelf cavity, which is in contact with a warming ocean. Estimating the rate of basal melt is the most challenging term in this balance because it is difficult to directly observe, but is also sensitive to changes in ocean temperature and other ocean-atmospheric processes such as the sea ice cycle.This project will join the Ocean2ice program, a UK led effort to integrate state of the art instrumentation, chemical analysis and modeling with the goal of improving the dynamical representation of ice shelf mas balance processes in Antarctic circulation models. In the Amundsen Sea, the shoaling warm Circumpolar Deep Water (CDW) and surficial glacial meltwater are two important diagnostic and prognostic terms in the ice shelf mass balance. By measuring the distribution of these water masses, using a suite of their distinct inert gas tracers ? 3He, 4He, Ne, Ar, Kr and Xe - together with their change over time, estimates of basal melt rates of some of the large West Antarctic ice shelves (e.g. Pine Island Glacier) are to be made. Greenland and the West Antarctic Ice Sheets together represent potentially more than a 10 m of increase in mean (global) sea surface height. How fast glacial mobilization rates may increase is of considerable societal importance.