为检验暴雨天气过程对地表参数扰动的敏感性,应用WRF2.2,给定其中的NOAH陆面模式参数(地表反照率、地表粗糙度、最小叶孔阻抗、土壤最大容积水含量)一系列初始扰动,模拟了2007年7月7~9日的南京暴雨过程。试验结果表明,此次暴雨天气过程对陆面参数的扰动比较敏感,尤其是对土壤最大容积含水量以及地表反照率扰动的影响更为明显。陆面参数的扰动首先改变感热、潜热、动量等通量,更主要的是通过陆气相互作用,改变大气底层水汽输送的环流形势,从而对暴雨强度和范围产生重要影响。
To test the sensitivity of the heavy rainfall simulation to the disturbance of land surface parameters, WRFV2.2 simulations for heavy rainfall events occurring during 7~9 July of 2007 were conducted by prescribing the disturbances of surface albedo, roughness length, the minimum stomatal resistance and the maximum volumetric soil water. The results indicate that this weather process is sensitive to the disturbances, especially to the disturbance of the maximum volumetric soil water and surface albedo. These dis- turbances firstly induce the change in the surfaces fluxes (e. g. , sensible and latent heat fluxes, and momentum flux), and more importantly, through the change in the low-level circulations for the transportation of water vapor due to land-atmosphere interactions, they can greatly influence the intensity and area of the heavy rainfall.