气象2012，Vol.38Issue(7)：769-778,10.
我国冬季冻雨和冰粒天气的形成机制及预报着眼点
Formation Mechanism and Forecast on Freezing Rain and Ice Pellet in Winter of China
摘要
Abstract
Based on upperair sounding and surface observations in winter of 20012010, the formation physical process of freezing rain and ice pellet at different regions are investigated. It is found that： （1） Except northern China region, the formation mechanism of freezing rain in China is mostly due to a warm rain process. In northern China region, freezing rain with melting process only accounts for 39%, but the higher latitudes, the higher ratio of melting process freezing rain. Warm layer aloft is an important charac teristic of freezing rain weather. And its main functions are water vapor supply and frontal system maintai ning, thus help to produce precipitation. Negative temperatures at low levels and surface could be the up most factor for freezing rain. （2） Melting process is the main formation mechanism of ice pellet in China. Generally, cloud top of ice pellet is higher than that of freezing rain. Warm layer＇s thickness and intensity of ice pellet are weaker than those of freezing rain. That is because weaker warm layer only partly makes ice crystal and snow aloft melt, thus ensure their refreezing within low levels. Wind speed at 700 hPa of ice pellet is commonly smaller than that of freezing rain, which, on the one hand, reflects the lower require ment of water vapor supply for ice pellet, and weaker warm layer aloft on the other hand. Cloud top,warm layer thickness and intensity, lowlevel dew point depression, wind speed at 700 hPa and surface temperature are good factors to discriminate freezing rain from ice pellet, but in different regions, the ef fectiveness of these factors is different. The main difference of freezing rain and ice pellet in Southwest China is the surface temperature, and other factors play a secondary role due to unobvious difference of them.关键词
冻雨/冰粒/探空资料/物理过程Key words
freezing rain/ice pellet/sounding data/physical process分类
天文与地球科学引用本文复制引用
漆梁波..我国冬季冻雨和冰粒天气的形成机制及预报着眼点[J].气象,2012,38(7):769-778,10.基金项目
2012年中国气象局城市气象防灾减灾专项“上海大城市积涝风险等级预报服务系统”资助 （）
