Yi Bingqi
School of Atmospheric Sciences and Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, 510275, China.
Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China.
Sci Rep. 2022 Jun 22;12(1):10539. doi: 10.1038/s41598-022-14608-w.
The representation of ice cloud optical properties in climate models has long been a difficult problem. Very different ice cloud optical property parameterization schemes developed based on very different assumptions of ice particle shape habits, particle size distributions, and surface roughness conditions, are used in various models. It is not clear as to how simulated climate variables are affected by the ice cloud optical property parameterizations. A total of five ice cloud optical property parameterization schemes, including three based on the ice habit mixtures suitable for general ice clouds, mid-latitude synoptic ice clouds, and tropical deep convective ice clouds, and the other two based on single ice habits (smooth hexagonal column and severely roughened column aggregate), are developed under a same framework and are implemented in the National Center for Atmospheric Research Community Atmospheric Model version 5. A series of atmosphere-only climate simulations are carried out for each of the five cases with different ice parameterizations. The differences in the simulated top of the atmosphere shortwave and longwave cloud radiative effects (CREs) are evaluated, and the global averaged net CRE differences among different cases range from - 1.93 to 1.03 Wm. The corresponding changes in simulated surface temperature are found to be most prominent on continental regions which amount to several degrees in Kelvin. Our results indicate the importance of choosing a reasonable ice cloud optical property parameterization in climate simulations.
在气候模型中表示冰云光学特性一直是个难题。基于对冰粒子形状习性、粒径分布和表面粗糙度条件的截然不同的假设，开发了非常不同的冰云光学特性参数化方案，并在各种模型中使用。目前尚不清楚模拟的气候变量如何受到冰云光学特性参数化的影响。在同一框架下，总共开发了五种冰云光学特性参数化方案，其中三种基于适用于一般冰云、中纬度天气冰云和热带深对流冰云的冰习性混合，另外两种基于单一冰习性（光滑六棱柱和严重粗糙的柱状聚集体），并在国家大气研究中心社区大气模型第5版中实现。针对五种不同冰参数化的情况，分别进行了一系列仅大气的气候模拟。评估了模拟的大气顶短波和长波云辐射效应（CREs）的差异，不同情况之间的全球平均净CRE差异范围为-1.93至1.03 W/m²。发现在大陆地区，模拟表面温度的相应变化最为显著，可达几开尔文。我们的结果表明在气候模拟中选择合理的冰云光学特性参数化的重要性。
