State-Dependence of the Equilibrium Climate Sensitivity in a Clear-Sky GCM
State-Dependence of the Equilibrium Climate Sensitivity in a Clear-Sky GCM
复制标题
晴空 GCM 中平衡气候敏感性的状态依赖性
DOI：
10.1029/2023gl104413
复制
发表时间：
2023
影响因子：
5.2
通讯作者：
Henry M
中科院分区：
文献类型：
--
作者：
Henry M
在各种气候模式中，从理想化的单柱模式到完全综合的气候模式，气候敏感性在310 K左右达到峰值。在这里，我们使用晴空三维大气模型增加CO2，辐射方案保持高CO2和温度水平的准确性。与此相反，我们的模式的平衡气候敏感性（ECS）平台约310 K。我们表明，这是由于大气环流放缓导致亚热带地区湿润，从而在二氧化碳值非常高的情况下增加了ECS。当相对湿度一定时，ECS峰与单柱模型结果一致。这项工作并不排除云或其他复杂过程对综合气候模式中的ECS产生影响。尽管这里的二氧化碳变化很极端，但这项研究强调了大气环流和相对湿度变化在气候敏感性定量评估中的重要性。
The climate sensitivity peaks around 310 K in a wide variety of climate models, ranging from idealized single column models to fully comprehensive climate models. Here, we increase CO2using a clear‐sky three‐dimensional atmospheric model with a radiation scheme which maintains accuracy for high CO2and temperature levels. In contrast, the Equilibrium Climate Sensitivity (ECS) of our model plateaus around 310 K. We show that this is due to the moistening of the subtropical regions caused by a slowdown in atmospheric circulation, which increases the ECS at very high CO2values. When relative humidity is fixed, the ECS peak is consistent with single column model results. This work does not rule out that clouds or other complex processes impact the ECS in comprehensive climate models. Though the changes in CO2here are extreme, this study underlines the importance of changes in atmospheric circulation and relative humidity in quantitative assessments of climate sensitivity.