新疆北部暖区强降雪中尺度环境与落区分析  

Analysis of Warm Zone Mesoscale Environmental and Heavy Snowfall Drop Zone in Northern Xinjiang

作　　者：庄晓翠[1] 崔彩霞[2] 李博渊 张林梅[1] 

机构地区：[1]新疆阿勒泰地区气象局,阿勒泰836500 [2]新疆气象局,乌鲁木齐830002 [3]新疆青河县气象局,青河836200

出　　处：《高原气象》2016年第1期129-142,共14页Plateau Meteorology

基　　金：科技部公益性行业(气象)科研专项(GYHY201106007);国家科技支撑计划(2012BAC23B01);中国沙漠气象科学研究基金(Sqj2013008)

摘　　要：利用常规气象观测资料、ECMWF、T639(1°×1°)再分析资料和FY-2C卫星云图资料,对2003—2013年11月至次年3月新疆北部出现26次12 h暖区强降雪天气过程的中尺度环境场特征和降雪落区进行了分析。结果表明:强降雪产生在极涡型和短波低槽型两种环流形势下,强降雪区位于低槽前部,低空急流出口区前侧辐合区和高空急流入口区右侧辐散区以及700 hPa和850 hPa辐合线和暖切变线东部、北部及干线东南部,地面辐合线附近减压升温的重叠区域内。强降雪区上空,对流层整层为>80%高湿区;500 hPa以下具有不稳定层结、风垂直切变大、斜压性强;700hPa辐合线和850 hPa暖切变线及干线、地面干线及辐合线易触发不稳定能量的释放,从而为暴雪的产生提供水汽、热力和动力条件。暖区强降雪主要发生在中尺度冷云团开始缓慢减弱东移的前部及云顶亮温TBB梯度最大区域的前部。通过上述分析总结出暖区强降雪落区三维空间配置模型。By used the conventional meteorological data,FY-2C satellite data,ECMWF data and reanalysis data of T639（1° ×1°）,the meso-scale environmental characteristics and snowfall area were analyzed of 26 warmzone 12 hours of heavy snowfall weather processes from 2003 to 2013（November to next March） in northern Xinjiang.The results showed that heavy snowfall produce in two kinds of atmospheric circulation,polar vortex type and short wave trough type,heavy snowfall area were located the front of the low trough,the front of exit area of low level jet;convergence zone and entrance area of high altitude jet,divergence area on it right;the northeast of convergence line of 700 hPa and 850 hPa warm shear line,the southeast of dry line;overlap area of the relief and heating-up near the ground convergence line.Over the heavy snowfall area,the whole troposphere be 80%humidity;Below 500 hPa with unstable stratification,strong vertical wind shear,strong baroclinicity;700 hPa convergence line and 850 hPa warm shear line and dry line,ground dry line and convergence line are easy to make the unstable energy release,thus providing conditions of water vapor,thermodynamic and dynamic for the production of Heavy Snow.Warm-zone snowfall mainly occurs when it began to moving eastward the front of meso-scale cold cloud cluster and the front of the biggest area of TBB genting bright temperature gradient.Finally,the three-dimensional space model is summarized for warm-zone heavy snowfall.

关 键 词：新疆北部 暖区强降雪 中尺度环境场分析 预报着眼点 

分 类 号：P458.11[天文地球—大气科学及气象学]