2010年1月阿勒泰地区特大暴雪过程的云图分析

Nephogram charactevistics in the process of snowstorm occurred in Altay Xijiang in January 2010

利用2010年1月6-8日常规观测资料和静止气象卫星FY-2C红外云图资料,分析了6-8日阿勒泰地区特大暴雪过程的环流特征和云图特征。结果表明:500hPa阻塞高压是产生暴雪天气的主导系统,西伯利亚冷涡是影响系统,短波槽、高低空西南急流、700hPa辐合线、850hPa暖切变的相互耦合,为暴雪天气提供了水汽和动力条件;阿勒泰东北高西南底的地势,对降雪具有增幅作用;在阿勒泰地区爆发性发展的中尺度冷云团(TBB≤-60℃)和境外生成的中尺度冷云团(TBB≤-60℃)先后影响下,阿勒泰地区出现暴雪,暴雪出现在中尺度冷云团外围TBB等值线梯度最大区域。

This research analyzed circulation and cloud chart features of the snowstorm in Ahay region by using of conventional observation information and data of the geostationary meteorological satellite FY -2C from 6th to 8th of January in 2010. The resuhs showed that 500hPa＇bloeking high presure was the dominant system for the formation of the snowstorm, Siberian cold vortex was the effect system of the snowstorm; The mutual coupling of short wave trough, lowhigh southwest jet stream, 700hPa＇convergence line and 850hPa＇warm shear provided water vapor and dynamic conditions for the formation of snowstorm. Topographic feature which was low in the southwest and high in the northeast in Ahay region would increase the snowfall. Under the successive influence of the mesoscale cold air mass（TBB≤ -60℃） which was explosively developing and the mesoscale cold air mass （ TBB ≤ - 60℃） generated from outside China, the snowstorm occurred in Ahay region, which appeared in TBB isoline gradient＇s maximum area of the periphery of the mesoseale cold air mass.