Sea surface temperature (SST) observations in the North Atlantic since 1870 reveal a region of enhanced warming off the northeastern coast of North America, and a region of cooling to the south of Greenland. It has been hypothesized that these adjacent SST trends are a result of long‐term changes in the buoyancy‐driven ocean circulation—a slowdown of the Atlantic Meridional Overturning Circulation. The impacts of these historical SST trends on the atmosphere are estimated using idealized atmospheric general circulation model experiments in which the global atmosphere is exposed to modern climatological forcing minus the aforementioned regional SST trends. The local response includes a negative North Atlantic Oscillation tendency and southward shift of the wind forcing for the subtropical gyre. Due to planetary wave propagation, the regional SST trends also induce a northward shift of the intertropical convergence zone over the Indian Ocean. Implications for climate feedbacks and projections are discussed.

中文翻译：

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1870–2019年，大气对北大西洋海温趋势的响应

自1870年以来在北大西洋进行的海表温度（SST）观测显示，北美洲东北海岸附近变暖的区域增加了，格陵兰南部的降温区域增加了。据推测，这些邻近的海温变化趋势是浮力驱动的海洋环流长期变化的结果，这是大西洋子午线俯仰环流速度减慢的结果。使用理想的大气一般环流模型实验估算了这些历史SST趋势对大气的影响，在该实验中，全球大气暴露于现代气候强迫下而没有上述区域SST趋势。局部响应包括北大西洋涛动的负面趋势和亚热带回旋的强迫向南移动。由于行星波的传播，区域海温趋势也促使印度洋上热带辐合带向北移动。讨论了对气候反馈和预测的影响。