DOGRAFS温度和风场的预报检验

Assessment for Forecast Effect of Temperature and Wind Field by DOGRAFS

利用新疆及周边地区2012 年11 月1 日-2013 年10 月31 日的地面2 m 温度和10 m风场的逐6 h 观测和预报资料,通过预报的均方根误差和平均误差的分析,对基于WRFv3.5 和WRFDAv3.4.1 的新疆快速更新循环数值预报同化系统（DOGRAFS）的预报效果进行检验评估.结果表明：DOGRAFS系统对地面2 m温度和10 m风速的预报具有较好的参考价值,二者的预报偏差均呈周期性变化,对2 m 温度预报整体呈“低温偏高,高温偏低”特点,采用12 UTC 初值场起报的预报结果对冬、春、夏季的高温预报冷偏差最小,采用06 UTC 初值场起报的预报结果对秋季的预报冷偏差最小,采用18 UTC 初值场起报的预报结果对冬、春、夏季的低温预报偏差最小,采用00 UTC 初值场起报的预报结果则对秋季的最低温预报偏差最小,各时次对18 UTC 的预报偏差均接近0 .偏差的空间分布上,大部分站点在不同季节、不同时次的偏差都在-2-2 益之间.对10 m风场的预报在秋季效果最好,冬季最差,预报平均误差整体从冬到秋逐季递减,夜间大于白天,四季中,采用18 UTC 初值场起报的预报效果最好.

Assessment of Xinjiang rapid update cycle forecast system（DOGRAFS）which is basedon the WRFv3.5 and WRFDAv3.4.1 is conducted, based on the predicting and observation datasetof 2 m temperature and 10m wind released every 6 hours in Xinjiang and surrouding areas fromNovember 1 of 2012 to October 31 of 2013 with the method of RMSE and ME. The results show asfollows. The forecast result of 2 m temperature and 10 m wind field is a good reference to theprediction operation. Both of the two methods have periodic change characteristics. It tends that forthe 2 m temperature, the forecast of low temperature is higher than the real temperature and that ofhigh temperature is lower, and the minimum error of forecast for high temperature appears inwinter, spring and summer when using the initial 12 UTC data, but in autumn the minimum error offorecast for the lowest temperature is based on 00 UTC initial data. The error of all prediction using18 UTC initial data is close to 0 ℃. For the deviation spatial distribution, most of the stations’biasis between -2-2 ℃in different seasons and initial times. The predicting ability for 10 m wind fieldis the best in autumn and worst in winter, the forecast error decreases from winter to autumn and isbigger at night than in daytime. For all seasons, the best predicting is based on the 18 UTC initialdata.