Large Changes in Sea Ice Triggered by Small Changes in Atlantic Water Temperature
Large Changes in Sea Ice Triggered by Small Changes in Atlantic Water Temperature
复制标题
大西洋水温的微小变化引发海冰的巨大变化
DOI：
10.1175/jcli-d-17-0802.1
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发表时间：
2018
影响因子：
4.9
通讯作者：
Spall, Michael A.
中科院分区：
文献类型：
--
作者：
Jensen, Mari F.;Nisancioglu, Kerim H.;Spall, Michael A.
使用具有理想地形的麻省理工学院大气环流模型的涡流解析配置，研究了海冰对穿过格陵兰岛-苏格兰海岭流入的大西洋水的温度的敏感性。在最后一个冰河时期，格陵兰岛的气候极其不稳定，海冰被认为覆盖了北欧海域。这一时期的气候急剧变化，被视为格陵兰岛的大规模突然变暖事件，被称为丹斯加德-厄施格（DO）事件，被认为是由北欧海域海冰快速消退引起的。在这里，我们表明，鉴于大西洋流入足够冷，并且格陵兰-苏格兰海岭的热量传输相应较低，北欧海域可能存在完整的海冰覆盖和类似北极的分层。海冰一旦形成，持续的海冰形成和融化会有效地使表层海洋变得清新，并使更深的层变得更加含盐。这在北欧海域造成了强烈的盐度分层，类似于今天的北冰洋，有一个寒冷的新鲜表层保护上覆的海冰免受下面温暖的大西洋海水的影响。北欧海域海冰对大西洋水温存在非线性响应，在流入温度发生微小变化的情况下，模拟海冰发生较大突变。这表明溶解氧事件更有可能发生在流入北欧海域的大西洋暖水减少期间。
The sensitivity of sea ice to the temperature of inflowing Atlantic water across the Greenland–Scotland Ridge is investigated using an eddy-resolving configuration of the Massachusetts Institute of Technology General Circulation Model with idealized topography. During the last glacial period, when climate on Greenland is known to have been extremely unstable, sea ice is thought to have covered the Nordic seas. The dramatic excursions in climate during this period, seen as large abrupt warming events on Greenland and known as Dansgaard–Oeschger (DO) events, are proposed to have been caused by a rapid retreat of Nordic seas sea ice. Here, we show that a full sea ice cover and Arctic-like stratification can exist in the Nordic seas given a sufficiently cold Atlantic inflow and corresponding low transport of heat across the Greenland–Scotland Ridge. Once sea ice is established, continued sea ice formation and melt efficiently freshens the surface ocean and makes the deeper layers more saline. This creates a strong salinity stratification in the Nordic seas, similar to today’s Arctic Ocean, with a cold fresh surface layer protecting the overlying sea ice from the warm Atlantic water below. There is a nonlinear response in Nordic seas sea ice to Atlantic water temperature with simulated large abrupt changes in sea ice given small changes in inflowing temperature. This suggests that the DO events were more likely to have occurred during periods of reduced warm Atlantic water inflow to the Nordic seas.
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影响因子：
5.2
作者：
S. Tietsche;D. Notz;J. Jungclaus;J. Marotzke
通讯作者：
S. Tietsche;D. Notz;J. Jungclaus;J. Marotzke
涡流和表面强迫在边缘海热传输和翻转环流中的作用
影响因子：
4.9
作者：
M. Spall
通讯作者：
M. Spall
S-T 坐标中的北冰洋水质量变换
影响因子：
3.5
作者：
P. Pemberton;J. Nilsson;M. Hieronymus;H. E. M. Meier
通讯作者：
H. E. M. Meier
影响因子：
12.1
作者：
Broecker, WS
通讯作者：
Broecker, WS
影响因子：
3.2
作者：
Losch, Martin;Menemenlis, Dimitris;Hill, Chris
通讯作者：
Hill, Chris