Model spread in tropical low cloud feedback tied to overturning circulation response to warming.
Model spread in tropical low cloud feedback tied to overturning circulation response to warming.
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DOI：
10.1038/s41467-022-34787-4
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发表时间：
2022-11-19
影响因子：
16.6
通讯作者：
Neelin, J. David
中科院分区：
文献类型：
--
作者：
Schiro, Kathleen A.;Su, Hui;Ahmed, Fiaz;Dai, Ni;Singer, Clare E.;Gentine, Pierre;Elsaesser, Gregory S.;Jiang, Jonathan H.;Choi, Yong-Sang;Neelin, J. David
在参与耦合模型比对项目第 6 阶段 (CMIP6) 的模型中，我们在此表明热带低云反馈的幅度与热带深对流及其对热带大气翻转环流的影响密切相关，这对气候敏感性估计的不确定性有很大影响。首先，热带上升面积的减少和强降水频率的增加导致云量大幅减少和对流层上层干燥，从而增加了长波冷却并减少了沉降减弱，有利于低云量减少（辐射-沉降路径）。其次，增加的长波冷却会降低对流层稳定性，这也会减少沉降减弱和低云量（稳定性-沉降路径）。总之，更大的高云减少和对流层上层干燥（负长波反馈）通过促进低云量的更大减少（正短波反馈）而导致 CMIP6 模型中更积极的云反馈。两条路径的不同强度对气候敏感性的模型间传播有很大贡献。热带低云反馈的幅度极大地增加了气候敏感性估计的不确定性，与热带深对流及其对热带大气翻转环流的影响密切相关。
Among models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6), here we show that the magnitude of the tropical low cloud feedback, which contributes considerably to uncertainty in estimates of climate sensitivity, is intimately linked to tropical deep convection and its effects on the tropical atmospheric overturning circulation. First, a reduction in tropical ascent area and an increased frequency of heavy precipitation result in high cloud reduction and upper-tropospheric drying, which increases longwave cooling and reduces subsidence weakening, favoring low cloud reduction (Radiation-Subsidence Pathway). Second, increased longwave cooling decreases tropospheric stability, which also reduces subsidence weakening and low cloudiness (Stability-Subsidence Pathway). In summary, greater high cloud reduction and upper-tropospheric drying (negative longwave feedback) lead to a more positive cloud feedback among CMIP6 models by contributing to a greater reduction in low cloudiness (positive shortwave feedback). Varying strengths of the two pathways contribute considerably to the intermodel spread in climate sensitivity. The magnitude of the tropical low cloud feedback, which contributes considerably to uncertainty in estimates of climate sensitivity, is closely linked to tropical deep convection and its effects on the tropical atmospheric overturning circulation.
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DOI：
10.1073/pnas.1418682112
发表时间：
2015-03-24
影响因子：
11.1
作者：
Lau, William K. M.;Kim, Kyu-Myong
通讯作者：
Kim, Kyu-Myong
影响因子：
5.2
作者：
Byrne, Michael P.;Schneider, Tapio
通讯作者：
Schneider, Tapio
影响因子：
8.4
作者：
Bony, S.;Semie, A.;Emanuel, K. A.
通讯作者：
Emanuel, K. A.
影响因子：
5.2
作者：
Bernstein, Diana N.;Neelin, J. David
通讯作者：
Neelin, J. David
DOI：
10.1073/pnas.1601472113
发表时间：
2016-08-09
影响因子：
11.1
作者：
Bony, Sandrine;Stevens, Bjorn;Medeiros, Brian
通讯作者：
Medeiros, Brian