Antarctic Bottom Water Warming in the Brazil Basin: 1990s Through 2020, From WOCE to Deep Argo
Antarctic Bottom Water Warming in the Brazil Basin: 1990s Through 2020, From WOCE to Deep Argo
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DOI：
10.1029/2020gl089191
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发表时间：
2020-09-28
影响因子：
5.2
通讯作者：
Steffen, Elizabeth L.
中科院分区：
文献类型：
--
作者：
Johnson, Gregory C.;Cadot, Chanelle;Steffen, Elizabeth L.
通过将新 Deep Argo 区域试点阵列的 2019-2020 年数据与 1989-1995 年整个盆地全深度纬向和经向水文剖面数据进行比较，对从南极洲向北穿过巴西盆地扩散的底层水域（4,500 至 5,900 dbar）变暖趋势 2.1 (+/- 0.4) m 摄氏度 yr(-1) 进行了量化。世界海洋环流实验（WOCE）。此外，浮子温度比相同底层水域的长期气候学温度高出约 0.046 摄氏度。盆地内的北大西洋下游深水没有显示出可检测到的变暖现象，但北大西洋上部深水在两次分析中都显示出变暖的证据。海底变暖加剧导致海底和深水之间的垂直密度分层每十年减少约 1%。这种变化与地表变暖的影响形成鲜明对比，地表变暖往往会增加垂直密度分层。
A warming trend of 2.1 (+/- 0.4) m degrees C yr(-1)in bottom waters (4,500 to 5,900 dbar) spreading north from Antarctica through the Brazil Basin is quantified by comparing 2019-2020 data from a new Deep Argo regional pilot array to 1989-1995 data from full-depth zonal and meridional hydrographic sections occupied across the basin before and during the World Ocean Circulation Experiment (WOCE). Additionally, float temperatures are about 0.046 degrees C warmer than those from a long-term climatology in those same bottom waters. Lower North Atlantic Deep Water in the basin shows no detectable warming, but Upper North Atlantic Deep Water exhibits evidence of warming in both analyses. The bottom-intensified warming results in a reduction in vertical density stratification between the bottom and deep waters of about 1% per decade. This change is in contrast with the effects of surface-intensified warming, which tends to increase vertical density stratification.