Ground-Based Microwave Study of LWP Spatial Anisotropy in Winter Clouds

The role of horizontal anisotropy of the cloud field in the radiation transfer is under investigation of Atmospheric Radiation Measurement (ARM) science team since the beginning of the program. It was recognized within last few years that the inhomogeneity of clouds could lead to large errors in heat fluxes calculations. It was calculated and experimentally proved (Gorchakova, Golitsyn et al. 2001) that the effect of horizontal inhomogeneity of winter clouds may led to many percent in estimation of radiative fluxes. Three-dimensional (3D) numerical models (Gu and Liou 2001) demonstrates very interesting effect that clouds with maximum overlapping produce less heating than those with random overlapping. Nevertheless, the experimental works that can provide numerical characteristics of that anisotropy are still rare.