Radiative Transfer Through Inhomogeneous Clouds: Stochastic Modeling Using Cloud Structure Observations

Evans/摘要 这项研究的目的是增加云结构如何影响辐射特性的理解，并改善计算方法的辐射传输的非均匀云参数化遥感。 这项研究将集中在使用随机辐射传输，其中集合平均辐射特性计算直接从概率分布，描述云的不均匀性。 随机建模是合适的，因为关于云结构的信息本质上是统计的。 来自飞机上的毫米波雷达和云探测器的数据将用于表征液态水云的空间结构，包括云内的变化，在随机传输概率分布方面。 将进行辐射传输建模，以了解云不均匀性的哪些方面对平均辐射效应最重要，以及如何用几个简单的参数最好地表达这些方面。 模拟的辐射和通量将与飞机和地面辐射计进行比较。 将寻求一种利用这些非均匀云参数快速计算随机辐射传输的近似方法，用于云辐射参数化。 还将进行确定性辐射传输建模，以调查上升流辐射统计数据与用于云遥感的基本不均匀性之间的关系。

Evans/Abstract The objective of this research is to increase the understanding of how cloud structure affects radiative properties and to improve methods of computing radiative transfer in inhomogeneous clouds for parameterizations an remote sensing. This research will focus on using stochastic radiative transfer, in which ensemble mean radiative properties are computed directly from probability distributions that describe cloud inhomogeneity. Stochastic modeling is appropriate because information about cloud structure is inherently statistical. Data from millimeterwave radars and cloud probes on aircraft will be used to characterize spatial structure in liquid water clouds, including within cloud variability, in terms of the stochastic transfer probability distributions. Radiative transfer modeling will be done to learn what aspects of cloud inhomogeneity are most important for the mean radiative effects and how these may be best expressed with a few simple parameters. The modeled radiances and fluxes will be compared with aircraft and ground based radiometers. An approximate method of using these inhomogeneous cloud parameters for rapidly computing stochastic radiative transfer for use in cloud radiation parameterizations will be sought. Deterministic radiative transfer modeling will also be done to investigate relationships between the statistics of upwelling radiances and the underlying inhomogeneity for use in remote sensing of clouds.