Kusahara Kazuya, Hasumi Hiroyasu, Williams Guy D
Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8568, Japan.
Nat Commun. 2011 Jan 18;2:159. doi: 10.1038/ncomms1156.
Antarctic Bottom Water (AABW) is a critical component of the global climate system, occupying the abyssal layer of the World Ocean and driving the lower limb of the global meridional overturning circulation. Around East Antarctica, the dense shelf water (DSW) precursor to AABW is predominantly formed by enhanced sea ice formation in coastal polynyas. The dominant source region of AABW supply to the Australian-Antarctic Basin is the Adélie and George V Land coast, in particular, polynyas formed in the western lee of the Mertz Glacier Tongue (MGT) and the grounded iceberg B9b over the Adélie and the Mertz Depressions, respectively. The calving of the MGT, which occurred on 12-13 February 2010, dramatically changed the environment for producing DSW. Here, we assess its impact using a state-of-the-art ice-ocean model. The model shows that oceanic circulation and sea ice production in the region changes immediately after the calving event, and that the DSW export is reduced by up to 23%.
南极底层水（AABW）是全球气候系统的关键组成部分，占据世界海洋的深海层并驱动全球经向翻转环流的下层。在东南极洲周围，AABW的致密陆架水（DSW）前身主要由沿海冰间湖海冰形成增强而产生。向澳大利亚-南极海盆供应AABW的主要源区是阿德利地和乔治五世地海岸，特别是分别在默茨冰川舌（MGT）西侧以及阿德利地和默茨凹陷上方的搁浅冰山B9b形成的冰间湖。2010年2月12日至13日发生的MGT崩解，极大地改变了DSW的生成环境。在此，我们使用先进的海冰-海洋模型评估其影响。该模型显示，该区域的海洋环流和海冰生成在崩解事件后立即发生变化，并且DSW输出减少了高达23%。
