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本文使用六个不同的最新大气模式进行了协调数值集合实验,评估和量化了全球海表面温度(SST)对1982-2014年冬季早期北极变暖的影响.本研究设计了两组实验:在第一组(EXP1)中,将OISSTv2逐日变化的海冰密集度和SST数据作为下边界强迫场;在第二组(EXP2)中,将逐日变化的SST数据替换为逐日气候态.结果表明:(1)EXP1的多模式集合总体平均值显示0.4℃/10年的近地表(约850 hPa)升温趋势,为再分析数据结果中升温趋势的80％.(2)在这六个模式中,模拟的变暖趋势均很强,幅度为0.36-0.50℃/10年.(3)全球海表温度可以解释北极对流层中低层EXP1的大部分模拟的变暖趋势,占再分析数据结果的58％.(4)再分析数据结果中,北极上空的对流层上层变暖(约200 hPa)不是由强迫信号而可能是由自然气候变率引起的.本文还探索了影响北极初冬变暖的可能源区,并讨论了该研究的局限性.“,”Coordinated numerical ensemble experiments with six different state-of-the-art atmosphere models were used to evaluate and quantify the impact of global SST (from reanalysis data) on the early winter Arctic warming during 1982-2014.Two sets of experiments were designed: in the first set (EXP1),OISSTv2 daily sea-ice concentration and SST variations were used as the lower boundary forcing,while in the second set (EXP2) the SST data were replaced by the daily SST climatology.In the results,the multi-model ensemble mean of EXP1 showed a nearsurface (～850 hPa) warming trend of 0.4 ℃/10 yr,which was 80％ of the warming trend in the reanalysis.The simulated warming trend was robust across the six models,with a magnitude of 0.36-0.50 ℃/10 yr.The global SST could explain most of the simulated warming trend in EXP1 in the mid and low troposphere over the Arctic,and accounted for 58％ of the simulated near-surface warming.The results also suggest that the uppertropospheric warming (～200 hPa) over the Arctic in the reanalysis is likely not a forced signal;rather,it is caused by natural climate variability.The source regions that can potentially impact the early winter Arctic warming are explored and the limitations of the study are discussed.