An Empirical Formula to Compute Snow Cover Fraction in GCMs
There exists great uncertainty in parameterizing snow cover fraction in most general circulation models (GCMs) using various empirical formulae, which has great influence on the performance of GCMs.This work reviews the commonly used relationships between region-averaged snow depth (or snow water equivalent) and snow cover extent (or fraction) and suggests a new empirical formula to compute snow cover fraction, which only depends on the domain-averaged snow depth, for GCMs with different horizontal resolution. The new empirical formula is deduced based on the 10-yr (1978-1987) 0.5°× 0.5° weekly snow depth data of the scanning multichannel microwave radiometer (SMMR) driven from the Nimbus-7Satellite. Its validation to estimate snow cover for various GCM resolutions was tested using the climatology of NOAA satellite-observed snow cover.
作 者： 吴统文 吴国雄 作者单位： 吴统文(State Key Laboratory of Numerical Modeling for Atmospherics Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029;Laboratory for Climate Study, National Climate Center, Beijing 100081)吴国雄(State Key Laboratory of Numerical Modeling for Atmospherics Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029)
刊 名： 大气科学进展(英文版) ISTIC SCI 英文刊名： ADVANCES IN ATMOSPHERIC SCIENCES 年，卷(期)： 2004 21(4) 分类号： 关键词： snow cover fraction parameterization satellite derived snow depth GCM