Balanced Cloud Radiative Effects Across a Range of Dynamical Conditions Over the Tropical West Pacific
Balanced Cloud Radiative Effects Across a Range of Dynamical Conditions Over the Tropical West Pacific
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DOI：
10.1029/2018gl080046
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发表时间：
2018-10
影响因子：
5.2
通讯作者：
C. Wall;D. Hartmann
中科院分区：
文献类型：
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作者：
C. Wall;D. Hartmann
利用云和大尺度垂直运动之间的瞬时关系，研究了环流对热带西太平洋上空观测到的云辐射效应的近抵消的影响。深对流云的覆盖率随着上升运动的加强而增加，但厚、中、薄砧云的比例几乎保持不变。因此，当在比单个风暴更大的尺度上平均时，大气顶部的净辐射对大尺度气流的敏感性很弱。因此，云辐射效应的平衡在大范围的大尺度环流中保持不变。研究了社区大气模式版本5再现观测到的云-环流关系的能力。模拟的对流云大大高估了深云和光学厚云的比例，低估了顶卷云的比例。这些结果表明，对于一些最先进的气候模式来说，模拟深对流云的关键属性仍然具有挑战性。
Instantaneous relationships between clouds and large‐scale vertical motion are used to study the impact of circulation on the near cancellation of cloud radiative effects that is observed over the tropical west Pacific Ocean. The coverage of deep‐convective clouds increases with stronger upward motion, but the proportion of thick, medium, and thin anvil cloud remains nearly constant. Thus, when averaging over scales larger than individual storms, the top‐of‐atmosphere net radiation is only weakly sensitive to the large‐scale flow. The balance in cloud radiative effects is therefore maintained across a wide range of large‐scale circulations. The ability of the Community Atmosphere Model Version 5 to reproduce the observed cloud‐circulation relationships is investigated. The simulated convective clouds substantially overestimate the proportion of deep and optically thick cloud and underestimate the proportion of anvil cirrus. These results demonstrate that simulating key properties of deep‐convective clouds remains challenging for some state‐of‐the‐art climate models.