T213L31全球中期数值天气预报系统2m温度预报误差源分析

T213L31全球中期数值天气预报系统的2m温度预报存在系统性偏低的问题，对业务预报影响很大，针对这一问题就产生原因对模式系统进行分析定位。经过一系列分析，通过对模式地形高度与观测站地形高度的比较，以及通过采用欧洲中心与国家气象中心的陆面过程初值得到的2m温度的比较，认为2m温度的误差是由于模式地形高度与实际地形高度存在较大差异以及2m温度预报对陆面过程所需的初值如土壤湿度等的敏感而实际采用特定值代替初始场的不科学性造成的。

Analysis of Error Sources of 2m Temperature Prediction in Global Medium-range NWF System T213L31,NMC

The global medium-range NWF system, T213L31, in National Meteorological Center, CMA, is found to exist the problem of systematic low about 2m temperature. In order to solve this problem, the sources of error of the model system are analyzed. Though a series of analysis, such as comparison of the topography height between model and observatory, and the analysis of two kinds of initial value from EC and CMA operational model land surface model, and so on, it shows that the error of 2m temperature is due to the difference of topography height between model and observatory, and incorrect initial soil moisture which is substituted by specifical value.