西北区域数值预报业务试验系统基本要素预报效果检验

Evaluation on Forecast Effect of Basic Meteorological Elements of Northwest Mesoscale Numerical Prediction System

利用全国地面及高空站点观测资料,对西北区域数值预报业务试验系统(northwest mesoscale numerical prediction system,NW-MNPS)2015年5月1日至2016年4月31日的预报结果进行检验分析,评估NW-MNPS模式对西北区域地面、高空要素及降水的预报效果。结果表明:NW-MNPS模式对西北区域气象要素预报整体效果较好,误差均在合理范围内。其中,对地面2 m温度预报白天偏低,夜晚偏高,昼夜差偏小;对2 m比湿预报白天偏高,夜晚偏低,昼夜差偏大;对10 m风速预报整体偏大。该模式对高空温度预报偏低,比湿预报偏高,风速预报低层偏大、高层偏小;对24 h降水预报,小雨、中雨的预报普遍偏多,而对大雨及以上量级的预报普遍偏少,尤其是大暴雨的预报。

Based on the meteorological observation data from surface and aerological stations in China,the results of basic meteorological elements forecasted by Northwest Mesoscale Numerical Prediction System(NW-MNPS)from 1 May 2015 to 30 April 2016 were tested,and the forecast effect of NW-MNPS to temperature,specific humidity on surface and upper level and precipitation in Northwest China was evaluated.The results indicated that the forecast effect of NW-MNPS to basic meteorological elements in Northwest China were better as a whole,the errors were in reasonable range.The forecasted temperature at 2 meters above the ground was lower in the daytime and higher at night compared with the observed,the temperature difference between day and night was smaller than the observation.On the contrary,the forecasted specific humidity at 2 meters above the ground was higher than the observed in the daytime and lower at night,the difference between day and night was bigger.However,the forecasted wind speed at 10 meters above the ground was higher than the observed overall.For the elements in upper levels,the forecasted temperature was lower than the observed,and the forecasted specific humidity was higher than the observed,while the forecasted wind speed was higher in low levels and lower in high levels than the observed.For 24 hours precipitation,the forecasted light and moderate rainfall were more than the observed,while the forecasted heavy rainfall and above grades were less than the observed,especially for the forecasted heavy rainstorm.