一次冷锋过程的云微物理特征分析以及飞机积冰预报检验

Cloud Microphysical Characteristic Analysis of a Cold Front Process and Aircraft Icing Forecast

利用NCEP GDAS/FNL资料分析了2013年2月19日黄淮至江南区域的一次冷锋过程的天气形势,结合MODIS卫星资料诊断云微物理特征,发现冷锋后的江淮大部至黄淮南部包括河南南部环流场配置和温度湿度条件好,云层较厚实且云内温度较低,云中含有足够的液态水,有利于生成积冰。接着采用IC指数法和Willam算法预报积冰概率和强度,用相近时次收到的航空器报告进行检验,发现Willam算法使用的MODIS卫星资料分辨率远高于IC指数法的常规气象资料数据,预报准确率也高于IC指数法。实际工作中同时使用两种方法,能给飞机积冰的预警服务提供可靠的判断依据。

Based on the NCEP GDAS/FNL data and MODIS satellite data,the synoptic situation and cloud microphysical characteristics of a cold front process from the Huanghuai region to Jiangnan region on 19 February 2013 are diagnosed.The circulation field and thick clouds,low temperature and enough liquid water were conducive to aircraft icing in most areas from Jianghuai to the southern Huanghuai region,including the southern Henan Province.The IC index method and Willam algorithm are used to forecast the probability and intensity of aircraft icing.Through the verification based on the nearest time aircraft reports,it is found that the resolution of MODIS satellite data by the Willam algorithm is much higher than that of NCEP GDAS/FNL data by the IC index method,and the prediction accuracy is higher also than that by the IC index method.Using two methods simultaneously in practical work is helpful to reliable early warning service for aircraft icing.