Do Southern Ocean Cloud Feedbacks Matter for 21st Century Warming?
Do Southern Ocean Cloud Feedbacks Matter for 21st Century Warming?
复制标题
DOI：
10.1002/2017gl076339
复制
发表时间：
2017-12-28
影响因子：
5.2
通讯作者：
Kay, J. E.
中科院分区：
文献类型：
--
作者：
Frey, W. R.;Maroon, E. A.;Kay, J. E.
在一个国家的最先进的气候模式的云相的改进产生了一个大的1.5K增加平衡气候敏感性（ECS，响应瞬间加倍CO2的表面变暖）通过extratrophic短波云反馈。在这里，我们表明，同样的模型改进只产生一个小的表面变暖增加在一个现实的世纪的排放情景。世纪变暖的小幅增加归因于热带外海洋的热量吸收。南大洋平均状态环流吸收热量，而北大西洋环流的减缓则作为减缓表面变暖的反馈。热带外海洋的持续热吸收意味着热带外云偏差可能不像其他地区的偏差那样对21世纪的变暖至关重要。云相和短波辐射的观测约束，产生一个大的ECS增加并不意味着在21世纪变暖的大变化。
Cloud phase improvements in a state-of-the-art climate model produce a large 1.5K increase in equilibrium climate sensitivity (ECS, the surface warming in response to instantaneously doubled CO2) via extratropical shortwave cloud feedbacks. Here we show that the same model improvements produce only a small surface warming increase in a realistic 21st century emissions scenario. The small 21st century warming increase is attributed to extratropical ocean heat uptake. Southern Ocean mean-state circulation takes up heat while a slowdown in North Atlantic circulation acts as a feedback to slow surface warming. Persistent heat uptake by extratropical oceans implies that extratropical cloud biases may not be as important to 21st century warming as biases in other regions. Observational constraints on cloud phase and shortwave radiation that produce a large ECS increase do not imply large changes in 21st century warming.