云三维结构对加热率廓线及通量影响的模拟

大气加热率强度与结构是驱动全球大气环流的关键因素,实际加热率分布与云三维结构密切相关。作者使用三维蒙特卡洛辐射传输模式,模拟计算了云分辨模式所得3个典型三维云场的加热率廓线及通量;定义了两个参数来同时描述加热率廓线的垂直分布和强度,通过与独立像素近似算法对比,定量统计分析了高分辨率下云三维结构对辐射的影响。结果表明,在高分辨率条件下云三维结构对加热率廓线和通量影响十分显著,且不同结构云场所体现的影响各具特点,提出需要考察现有大气模式中云三维结构对当前所用加热率计算方案的订正方向。

A Simulation of Effects of Cloud 3D Structures on Heating Rate Profiles and Fluxes

The strength and structure of broadband heating rate directly drives the global atmospheric circulations and is largely determined by cloud three dimensional (3D) structures. Heating rate profiles and fluxes of three cloud fields resolved by Cloud Resolving Models (CRM) are simulated by a broadband 3D Monte Carlo radiative transfer model, which gives a quantitative and statistical estimate about the effects of cloud 3D structures on radiation in high resolution by comparing with Independent Pixel/Column Approximation (IPA/ICA). Two parameters are defined to describe the vertical distribution and strength simultaneously. The results show that the impacts of cloud 3D structures on radiation are very significant under high resolution conditions and different kinds of cloud fields have various characteristics. A direction of the revising on current heating rate calculation scheme in existing atmospheric models due to cloud 3D structures is raised.