The Sea Ice Thickness in the Atlantic Sector of the Southern Ocean

海冰覆盖了世界海洋的大部分地区。由于它覆盖了数百万平方公里，它显著地调节了海洋和大气之间的水、热量和动量的表面通量。因此，它对两个半球的区域气候和极地自然环境有着深远的影响。由于其反射阳光的能力或对极地海洋淡水收支的影响，它还在全球气候系统中发挥着重要作用。因此，研究海冰的变化已成为地球系统科学的一个重要领域。随着北极海冰的迅速减少，南极海冰覆盖也引起了越来越多的科学兴趣。与海冰的范围和浓度相反，海冰的厚度通常不能从太空测量到足够的精度。此外，潜艇声纳对南极冰层厚度的测量是不可用的。监测南大洋海冰厚度长期变化的唯一方法是系泊向上的声纳（ULSs）。自1990年以来，阿尔弗雷德·韦格纳研究所（AWI）在南大洋的大西洋部分维护着13个uls阵列。这个项目的重点是分析uls数据在海冰厚度变化和可能的长期趋势方面。计划寻找由ULS测量得到的海冰厚度与其他海洋和大气特性（如南方环模）之间可能的相关性，以确定海冰厚度变化的强迫机制。该项目的另一个目标是建立一个统一的ULS草稿测量数据集，该数据集可用于验证卫星衍生的冰厚估计和海冰模型。

Sea-ice covers large regions of the World Ocean. As it blankets millions of square kilometers, it significantly regulates the surface fluxes of water, heat and momentum between the ocean and the atmosphere. Thus, it has a profound influence on the regional climate and the polar physical environment in both hemispheres. It also plays a major role in the global climate system, due to its ability of reflecting sunlight or its influence on the freshwater budget of the polar oceans. Examining the changes of sea-ice has thus become an important field in Earth System Science. With the rapid decline of Arctic sea-ice, also the Antarctic sea-ice cover has attracted more scientific interest. Contrary to the sea-ice extent and concentration, the thickness of sea-ice is not routinely measured from space with sufficient accuracy. Moreover, submarine sonar measurements of ice thickness are not available for the Antarctic. The only way of monitoring the long-term variations of the sea-ice thickness in the Southern Ocean are moored upward looking sonars (ULSs). Since 1990 the Alfred Wegener Institute (AWI) maintains an array of 13 ULSs in the Atlantic sector of the Southern Ocean. This project is focussed on the analysis of ULS-data in terms of sea-ice thickness variations and possible long-term trends. It is planned to find possible correlations between the sea-ice thickness derived from ULS measurements and other oceanic and atmospheric properties (e.g. the Southern Annular Mode) to identify the forcing mechanisms of sea-ice thickness changes. Another goal of this project is to set up a consistent dataset of ULS draft measurements which can be used to validate satellite-derived ice thickness estimates and sea-ice models.