Drijfhout Sybren
Royal Netherlands Meteorological Institute, PO Box 201, 3730AE De Bilt, Netherlands.
University of Southampton, National Oceanography Centre Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK.
Sci Rep. 2015 Oct 6;5:14877. doi: 10.1038/srep14877.
A collapse of the Atlantic Meridional Overturning Circulation (AMOC) leads to global cooling through fast feedbacks that selectively amplify the response in the Northern Hemisphere (NH). How such cooling competes with global warming has long been a topic for speculation, but was never addressed using a climate model. Here it is shown that global cooling due to a collapsing AMOC obliterates global warming for a period of 15-20 years. Thereafter, the global mean temperature trend is reversed and becomes similar to a simulation without an AMOC collapse. The resulting surface warming hiatus lasts for 40-50 years. Global warming and AMOC-induced NH cooling are governed by similar feedbacks, giving rise to a global net radiative imbalance of similar sign, although the former is associated with surface warming, the latter with cooling. Their footprints in outgoing longwave and absorbed shortwave radiation are very distinct, making attribution possible.
大西洋经向翻转环流（AMOC）的崩溃通过快速反馈导致全球变冷，这些反馈会选择性地放大北半球（NH）的响应。这种变冷如何与全球变暖相抗衡长期以来一直是一个猜测的话题，但从未使用气候模型进行过探讨。本文表明，AMOC崩溃导致的全球变冷在15至20年的时间里抵消了全球变暖。此后，全球平均温度趋势逆转，变得类似于没有AMOC崩溃的模拟结果。由此产生的表面变暖停滞期持续40至50年。全球变暖和AMOC引起的北半球变冷受相似反馈的支配，尽管前者与表面变暖相关，后者与变冷相关，但却产生了具有相似符号的全球净辐射不平衡。它们在向外长波辐射和吸收短波辐射中的特征非常明显，使得归因成为可能。
