Decadal global temperature variability increases strongly with climate sensitivity
Decadal global temperature variability increases strongly with climate sensitivity
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十年间全球温度变化随着气候敏感性的增加而急剧增加
DOI：
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发表时间：
2019
影响因子：
30.7
通讯作者：
M. Williamson
中科院分区：
文献类型：
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作者：
F. Nijsse;P. Cox;C. Huntingford;M. Williamson
与气候相关的风险不仅取决于温室气体的变暖趋势，而且取决于趋势的可变性。然而，对气候变化影响的评估往往侧重于全球变暖的最终水平1，只是偶尔关注全球变暖的速度，很少关注趋势的变化。在这里，我们表明，对温室气体排放更敏感的模型（即更高的平衡气候敏感性（ECS））在几年到几十年的时间尺度上也具有更高的温度变率。与直觉相反的是，高敏感性气候以及快速十年变暖的可能性更高，也比低敏感性气候更有可能有历史“间断”时期。冷却或中断几十年的历史时期，这一直是相对罕见的，是两倍以上的可能性在一个高ECS的世界（ECS = 4.5 K）相比，低ECS的世界（ECS = 1.5 K）。由于ECS还影响未来情景下的背景变暖率与未减轻的人为强迫，超暖十年的可能性-超过十倍的平均全球变暖的20世纪-是更敏感的ECS。温度的预测往往集中在最大变暖水平，与变率较少考虑。研究模式的年代际变率表明，那些具有较高平衡气候敏感性的模式也有更高的机会出现超级变暖和间断期。
Climate-related risks are dependent not only on the warming trend from GHGs, but also on the variability about the trend. However, assessment of the impacts of climate change tends to focus on the ultimate level of global warming1, only occasionally on the rate of global warming, and rarely on variability about the trend. Here we show that models that are more sensitive to GHGs emissions (that is, higher equilibrium climate sensitivity (ECS)) also have higher temperature variability on timescales of several years to several decades2. Counter-intuitively, high-sensitivity climates, as well as having a higher chance of rapid decadal warming, are also more likely to have had historical ‘hiatus’ periods than lower-sensitivity climates. Cooling or hiatus decades over the historical period, which have been relatively uncommon, are more than twice as likely in a high-ECS world (ECS = 4.5 K) compared with a low-ECS world (ECS = 1.5 K). As ECS also affects the background warming rate under future scenarios with unmitigated anthropogenic forcing, the probability of a hyper-warming decade—over ten times the mean rate of global warming for the twentieth century—is even more sensitive to ECS.Projections of temperature often focus on maximum warming levels, with variability less often considered. Investigating decadal variability in models shows those with higher equilibrium climate sensitivity also have a higher chance of super warming, and hiatus periods.