NSFPLR-NERC Thwaites-Amundsen Regional Survey and Network (TARSAN)

由于最近的气候变暖和海洋环流的相关变化，阿蒙森海海湾（ASE）的斯韦茨和邻近的冰川正在迅速失去质量。冰盖模型表明，在不久的将来，来自ASE的质量损失将进一步加速，导致南极西部冰盖（WAIS）的最终崩塌，在短短500年内将全球海平面提高2.5米。然而，这种模式预测仍然缺乏对在接地带及其附近的主要过程以及这些过程的大气和海洋驱动因素在空间和时间上的详细了解。拟议的项目旨在限制这些影响Thwaites和Dotson冰架的主要过程，以及由这些冰架支撑的接地冰块。具体目标是：1)在冰架上安装大气-冰-海洋多传感器远程自治站（AMIGOS），为期两年，提供亚日连续同步观测海洋、冰川和大气条件；2)测量靠近冰架锋面的大陆架上的海洋特性（使用海豹标记、滑翔机和船舶调查以及现有的系泊和CTD-cast数据），并进入冰架下腔（使用自主水下航行器auv），详细描述影响冰架底部的海洋运输和热通量；3)利用雷达、有源地震和重力测量方法，对两个冰架站点当前冰架和亚冰架空腔几何形状、冰流和温度特性进行约束，以更好地了解海洋和大气对冰盖变化的影响。

Thwaites and neighboring glaciers in the Amundsen Sea Embayment (ASE) are rapidly losing mass in response to recent climate warming and related changes in ocean circulation. Ice-sheet models suggest that the mass loss from the ASE will further accelerate in the near future, initiating an eventual collapse of the West Antarctic Ice Sheet (WAIS), raising the global sea level by up to 2.5 meters in as short as 500 years. Such model predictions, however, are still lacking spatially and temporally detailed understanding of the dominant processes at and near grounding zones and the atmospheric and oceanic drivers of these processes. The proposed project aims to constrain these dominant processes affecting the Thwaites and the Dotson Ice Shelves, as well as the grounded ice mass buttressed by these ice shelves. Specific objectives are: 1) to install atmosphere-ice-ocean multi-sensor remote autonomous stations (AMIGOS) on the ice shelves for two years to provide sub-daily continuous observations of concurrent oceanic, glaciologic, and atmospheric conditions; 2) measure ocean properties on the continental shelf adjacent to the ice-shelf fronts (using seal tagging, glider-based and ship-based surveys and existing moored and CTD-cast data) and into the sub-ice-shelf cavities (using Autonomous Underwater Vehicles AUVs) to detail ocean transports and heat fluxes affecting the ice-shelf base; and 3) constrain the current ice-shelf and sub-ice-shelf cavity geometry, ice flow, and firn properties for the two ice-shelf sites (using radar, active-source seismic and gravimetric methods) to better understand the impact of ocean and atmosphere on the ice-sheet change.