We explore the effect of Atlantic meridional overturning circulation (AMOC) slowdown on global marine heatwaves (MHWs) under anthropogenic warming by maintaining AMOC strength in climate model simulations throughout the 21st century. The AMOC slowdown has an insignificant effect on global MHWs during the past four decades, except those over the North Atlantic warming hole (NAWH) where the weakened AMOC reduces the occurrence and duration of MHWs by about half by creating a cooler mean-state sea surface temperature. As the AMOC continues weakening in current century, its effect becomes significant on MHWs in the North Atlantic and Pacific Oceans. The weakened AMOC induces a bipolar-seesaw-like change in MHW frequencies, with more frequent MHWs in the Southern Hemisphere but less frequent MHWs in the North Hemisphere except over the NAWH. The reason for the exception is that the NAWH region would enter a near-permanent MHW state without an AMOC slowdown.

中文翻译：

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减弱的大西洋经向翻转环流在气候变暖中调节海洋热浪的作用

我们通过在整个 21 世纪的气候模型模拟中保持 AMOC 强度来探索大西洋经向翻转环流 (AMOC) 放缓对人为变暖下全球海洋热浪 (MHW) 的影响。在过去的 40 年中，AMOC 放缓对全球 MHW 的影响微不足道，但北大西洋变暖洞 (NAWH) 上的那些减弱的 AMOC 通过创建更冷的平均状态海面将 MHW 的发生和持续时间减少了大约一半温度。随着本世纪 AMOC 的持续减弱，其对北大西洋和太平洋的 MHW 的影响变得显着。减弱的 AMOC 引起 MHW 频率的双极跷跷板式变化，南半球的 MHW 频率更高，但北半球的 MHW 频率较低，除了 NAWH。