摘要
利用常规观测资料、NCEP再分析资料及卫星TBB资料,对2013年4月19-20日山东极端暴雪过程的环流背景、物理量诊断、地形作用及其中尺度特征等进行了综合分析。结果表明:此次暴雪天气是以500 h Pa高空槽、700 h Pa西南低空急流及切变线、以及850 h Pa以下低层东北风作为环流背景的回流性质降雪;暴雪期间,相对湿度≥90%的高湿区明显下传,南方的暖湿空气沿着低层冷垫爬升,到达一定高度以后,水汽凝结产生降雪,强降雪落区并不位于强上升运动的中心位置,而是位于最大中心值的偏北一侧,在28°N-40°N之间高空有一明显的能量锋区,且随纬度的增高而向高空倾斜;近地面层有明显的辐合流场,TBB分布反映出暴雪期间有中小尺度系统配合,TBB最大值在-45^-40℃之间;此次极端暴雪过程中地形对温度的急剧下降起了重要的作用。
Based on conventional surface data,reanalysis data from NCEP and TBB data,the comprehensive analysis of snowstorm occurred in Shandong province from 19 to 20 April 2013 was done. The results showas following. It is the main synoptic background to generate the snowstorm that 500 h Pa upper trough,700 h Pa southwest lowlevel jet and the shear line and 850 h Pa low-level northeaster made the backflowsnow. During the snowshorm,snowstorm area physical quantity in the space above the vertical section shows: A relative humidity of 90% or more under high humidity area downloaded and warm moist air along the southern low-level cold climbed,and after reach a certain height,the water vapor condenses snow,and snowstorm fell the center of the area was not located in the strong upward movement,but located in the north side of the center value biggest,between 28°N ~ 40°N has a high energy frontal zone,and along with the increase of latitude leaning to high altitude. Near the ground layer is an obvious convergence field,and distribution of TBB reaction during the snow-storm had meso-microscale system coordination,TBB maximum in between- 45 ^- 40 ℃. Terrain in the extreme blizzard events over a rapid decline in the temperature played a very important role.
出处
《高原气象》
CSCD
北大核心
2015年第4期1131-1138,共8页
Plateau Meteorology
基金
国家自然科学基金项目(41475038)
中国气象局预报员专项(CMAYBY2014-039)
山东省气象局重点课题(2013sdqxz02)
潍坊市气象局科研项目(2014wfkt01)
