山东沿海偏北大风的天气学模型和物理量特征  

Synoptic model and physical quantity features of the north gale wind over Shandong coast

作　　者：杨晓霞[1] 盛春岩[2] 沈建国[3] 肖明静[2] 华雯丽[4] 

机构地区：[1]山东省气象台,山东济南250031 [2]山东省气象科学研究所,山东济南250031 [3]山东省气象局,山东济南250031 [4]成都信息工程学院大气科学系,四川成都610072

出　　处：《海洋预报》2014年第3期45-55,共11页Marine Forecasts

基　　金：公益性行业(气象)科研专项(GYHY201106006);山东省气象局重点课题(2009sdqxz01)

摘　　要：应用观测资料和MICAPS3气象资料显示系统,分析研究了近十年山东沿海7级以上偏北大风的特征。对两年内36次区域性大风个例,以地面影响系统为主,把偏北大风分为四种类型:冷锋型、温带气旋型、回流冷空气型和北上热带气旋型,建立了偏北大风的天气学模型。分月份、分类型统计分析了偏北大风期间地面气压梯度、锋后冷高压强度、锋前低压强度、高低压之间的气压差、850 hPa锋区强度、850hPa偏北风风速、850hPa24h变温,给出了阈值和平均值;分析研究了各类型9级以上偏北大风气象要素的临界值。对各种类型偏北大风的物理量空间结构和形成机理进行了研究,结果表明:冷锋偏北大风在中低层为较强的下沉运动,低层辐散,有高空动量下传,偏北大风主要是快速南下的冷空气、下沉运动造成的辐散风和高空动量下传的共同作用;气旋型偏北大风在高空为正涡度、低层辐合、整层为上升运动,北大风主要取决于快速旋转的气旋性环流和向气旋中心的辐合运动;回流型偏北大风的中高空为上升,近地面层为下沉,偏北大风主要是低层快速南下的冷空气的水平运动。Based on observational data and MICAPS3 system software, the climatic characters of north gale higher than Level 7 over Shandong coast in the last decade were analyzed. For 36 gale cases, the weather systems on ground were divided into four types： cold front, temperate cyclone, refulgence cold air and toward north moving tropical cyclone. The synoptic models of north gale on Shandong coast were established. The meteorological elements, such as the pressure gradient, cold high intensity behind cold front, low pressure intensity of cold front foreside and the difference value between high and low pressure center on ground, the intensity of front, north wind speeds and temperature change in 24h on 850hPa, were analyzed and researched. Threshold values and average values for aforementioned physical quantity and critical values of these physical quantities parameter of north gale wind higher than Level 9 in each model is studied. The physical quantity space structure characteristic and forming mechanism of north gale wind of every model were also examined. The results show that： with stronger downward movement at middle-low level and divergence at low level in cold front model, which deducing momentum on high level transmission toward low level, the north gale winds were caused main- ly by the action of cold air high-speed moving toward south, divergence wind and momentum on high level downward conveying. In the cyclone model, with positive vorticity at high level, convergence at low level and rise movement all level, the north gale wind rested with the speed rotating cyclone circulation and convergence movement toward cyclone center. In the refulgence cold air model, with rise movement at middle-high level and downward movement at near ground level, the north gale wind was caused mainly by the cold air horizontal fast moving toward south.

关 键 词：山东沿海偏北大风 气候特征 天气学模型 物理量指标 物理量空间结构 形成机理 

分 类 号：P732[天文地球—海洋科学]