新疆北部持续性暴雪过程成因分析  

Cause Analysis of Persistent Heavy Snow Processes in the Northern Xinjiang

作　　者：杨莲梅[1,2] 刘雯[1,2] 

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,乌鲁木齐830002 [2]中亚大气科学研究中心,乌鲁木齐830002

出　　处：《高原气象》2016年第2期507-519,共13页Plateau Meteorology

基　　金：新疆维吾尔自治区自然科学基金(2014211A052)

摘　　要：利用1964-2010年新疆天山及其以北地区(新疆北部)45个气象观测站逐日降水资料和NCEP/NCAR逐日2.5°×2.5°经纬网格客观分析资料,提出了新疆北部持续性暴雪过程客观定义,根据定义1964 2010年共出现36次持续性暴雪过程,按暴雪落区可分为四类暴雪型:北疆型25次、北疆西部北部型9次、北疆沿天山型1次、北疆西部型1次。重点分析了北疆型和北疆西部北部型暴雪过程的大尺度环流背景、关键环流系统配置和水汽输送异常特征。结果表明:(1)北疆型暴雪环流分为经向I型、II型和纬向型,经向I型又可分为极涡偶极与中高纬3波配置型和极涡偶极与中高纬2波配置型;经向II型可分为极涡偶极型与中高纬2波配置和极涡单极型与中高纬2波配置;纬向型则表现为高纬极锋锋区波动和中低纬副热带锋区波动汇合于新疆地区引发暴雪。(2)北疆西部北部型暴雪环流分经向型和纬向型,经向型有极涡偶极与中高纬3波配置、极涡单极与中高纬3波配置,纬向型环流表现为乌拉尔山槽和里咸海槽汇合于新疆地区引发暴雪;(3)上述环流型新疆上空均存在300 hPa极锋急流、500 hPa强西风锋区和700 hPa低空西风急流配置,暴雪区处于极锋急流入口右侧辐散区和低空急流出口右侧辐合区的高低空配置。(4)造成新疆持续性暴雪的水汽源地有高纬北大西洋、巴伦支海,中纬地中海、里咸海,低纬红海,环流配置不同水汽输送路径有所差异,但主要以中低纬水汽输送为主。Based on daily precipitation data of 45 meteorological observation stations in Tianshan Mountions and its north to Xinjiang（northern Xinjiang）during 1964-2010 and NCEP/NCAR 2. 5° × 2. 5° daily reanalysis data,the persistent heavy snow process in northern Xinjiang is defined. There were 36 processes from 1964 to 2010,and they can be classified into 4 patterns based on the location of the snowstorm,25 times in northern Xinjiang,9 times in north and west of northern Xinjiang,1 time along the Tianshan Mountains,1 time in west of northern Xinjiang. The large scale circulation backgrounds,key circulation system configuration and water vapor transport anomalies of processes in northern Xinjiang and in north and west of northern Xinjiang have been analyzed. The results show：（1）Circulation of heavy snow processes in northern Xinjiang can be classified into 3patterns：the meridional pattern Ⅰ,the meridional pattern Ⅱ and the zonal pattern. The meridional pattern Ⅰ can be classified into 2 patterns：Two polar vortex centers in the Northern Hemisphere with two and three waves in middle high latitudes respectively. The meridional pattern Ⅱ can be classified into 2 patterns：one and two polar vortex centers in the Northern Hemisphere with two waves in middle high latitudes respectively. The zonal pattern：Snowstorms were caused by meeting with wave from frontal zone high latitudes and subtropical front in middle-low latitudes over Xinjiang.（2）Circulation of snow processes in north and west of northern Xinjiang can be classified into 3 patterns：one and two polar vortex centers in the Northern Hemisphere with three waves in middle high latitudes,and the zonal pattern manifested as the West Siberia trough and trough between the Caspian Sea and the Aral Sea jointed together over Xinjiang and caused the snowstorm.（3）These circulation patterns have the same configuration：polar front jet on 300 h Pa,strong westerly frontal zone on 500 h Pa,low- level westerly jet on 700 h Pa,heavy snow area locate

关 键 词：新疆北部持续性暴雪 中期-延伸期 大尺度环流背景 影响系统 水汽输送 

分 类 号：P448[天文地球—大气科学及气象学]