Based on a global ocean-ice coupled numerical model,we study the impact of different spatio-temporal resolutions of atmospheric forcing fields on the numerical simulation of AMOC (Atlantic meridio-nal overturning circulation)and SST (sea surface temperature).Sensitivity experiments show that spatio-temporal resolution of atmospheric forcing field can significantly influence both SST and AMOC.Com-pared with control run (6 hourly),coarser spatio-temporal forcing field lead to weaker AMOC and warmer SST.AMOC index in monthly forcing field experiment decreased by 6.7 Sv (34% lower)with respect to experiment with 6 hourly forcing field.In 6 hourly forcing field runs,AMOC index of coarser spatial reso-lution decreased by 1.4Sv than that of finer spatial resolution.Analysis of upper ocean current and sea sur-face heat flux indicate that coarser spatio-temporal forcing field can result in weakening of sea surface winds,which is the major cause of weaker AMOC and warmer SST.%基于全球海洋-海冰耦合数值模式,研究了不同时间和空间分辨率的海表驱动场对大西洋经向翻转环流(Atlantic Meridional Overturning Circulation,AMOC)和海表面温度(Sea Surface Temperature,SST)模拟的影响。敏感性数值实验结果表明,海表驱动场时间和空间分辨率的不同不仅会影响 SST 的模拟,而且会显著影响 AMOC强度的模拟。相比高时间分辨率的海表驱动场,时间和空间分辨率的降低会造成 AMOC 模拟强度的减弱和 SST的升高。月平均驱动场驱动的 AMOC 比6 h 分辨率驱动场驱动的控制实验减少6.7 Sv,降低了34%；同为6 h 分辨率,粗空间分辨率大气驱动场模拟的 AMOC 比高空间分辨率实验减少1.4 Sv,降低了7%。对海洋上层流场和海表热通量进一步分析表明,低时间和空间分辨率的海表风场的减弱是导致 AMOC 减弱和 SST 升高的主要原因。
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