摘要
利用2000—2012年11月—次年3月北疆51个测站逐日降水量资料和NCEP/NCAR逐日4次1°×1°再分析资料,分析了该时段内北疆11次典型暴雪天气的水汽特征。结果表明,北疆暴雪可分为北疆西部及北疆沿天山型、北疆北部及东部型和北疆西部及西天山型;水汽源地主要分布在地中海附近、红海或波斯湾两个海域附近;水汽输送有西方、西南和西北3条路径,以西南路径最多、西北路径较少。水汽输送最高层接近300hPa,最强水汽输送层位于650～750hPa之间,暴雪出现前北疆600～1 000hPa高度之间存在一定的水汽辐合。北疆地区中低层水汽输送、辐合强度、范围及持续时间与暴雪强度具有较好的正相关关系,暴雪出现前最强水汽输送、水汽辐合以及高空、低空急流的最低阈值为北疆暴雪的定量、定点预报提供了参考依据。
Using the daily precipitation at 51 weather stations in the Northern Xinjiang from November to March during 2000—2012 and daily water vapor of NCEP/NCAR 6 h 1°×1° reanalysis data,the water vapor characteristics of 11 typical heavy snowstorm cases were studied.The result shows that the 11 cases are classified into 3 types： West of Northern Xinjiang and along Tianshan edge,north and east of Northern Xinjiang,west of Northern Xinjiang and west Tianshan.There are two main water vapor sources： Near the Mediterranean Sea,the Red Sea or near the Persian Gulf.There are two water vapor transport routes which are west,southwest and northwest,respectively.Water vapor from southwest route is more,that from northwest route is less.The top of water vapor is close to 300 hPa.The strongest water vapor transport level is between 650~750 hPa.Before the every occurrence of 11 heavy snowstorm processes,there are water vapor convergence between 600~1 000 hPa in Northern Xinjiang.There are positive correlations between the snowstorm intensity and water vapor convergence between 600~1 000 hPa,as well as the convergence strength,rang and duration time in Northern Xinjiang.Hence,some lowest values of the strongest water vapor transport,water vapor convergence and the upper and lower level jet streams are resented also and gave useful references for accurate heavy snowstorm forecasting.
出处
《高原气象》
CSCD
北大核心
2013年第4期1115-1125,共11页
Plateau Meteorology
基金
科技部公益性行业科研专项(GYHY201106007)
关键词
暴雪
水汽特征
北疆
Heavy snowstorm
Water vapor characteristic
Northern Xinjiang
