摘要
对流性天气的气候背景分析是临近预报的基础,是做好北京2008年奥运气象服务必不可少的准备工作。对北京地区暖季(5—9月)发生雷暴、冰雹、暴雨和大风4种对流天气当日08时高空探测资料(2002—2005年)的压、温、湿、风等气象参数进行气候统计和分析,并与气候平均值进行比较,以揭示发生对流天气的环境条件及规律,为预报业务提供参考。结果表明:4种对流天气日所在各月高空要素均表现出比较典型的特征;500 hPa急流和对流产生有一定的对应关系:急流存在时,容易产生对流性天气,且雷暴、大风、暴雨甚至冰雹同时发生的概率增大;对流性天气过程与风向垂直切变有很好的对应关系,强雷暴、冰雹、暴雨和大风4种对流日500 hPa以下出现顺转平均发生率为84.2%。风向较强的逆转常常发生混合性对流天气,且逆转高度越高、对流越强。整层顺转容易发生多站暴雨,但雷暴发生较少。
Climate background analysis of convective weather was the foundation of nowcasting, which was the necessary to Olympics weather service in 2008. Thus, air pressure, temperature, humidity and wind speed from up- perair sounding intraday 0800 （BST） data （2002-2005） under convective weather of warm season （May to September） including thunderstorm, hail, rainstorm and high wind were analyzed, and they were compared with climate average values, in order to reveal the environmental conditions and rules caused the convection and to serve for forecast operation. The results indicated that relative monthly upperair elements of convective weather were of typical characteristics. There was a corresponding relationship between 500 hPa jet and convection. Convective weather occurred easily while jet existed, and the joint probabilities of thunderstorm, high wind, rainstorm and hail increased. There was a better corresponding relationship between convective and vertical shear of wind direction. The average probability of wind direction that veered clockwise under 500 hPa in convective weather was 84.2 %. Mixed convective weathers often occurred when wind directions veered counterclockwise. The higher the counter- clockwise rotation height was, the stronger the convection was. Rainstorm occurred easily in many stations if the entire wind directions veered clockwise, but the thunderstorms occurred uneasily.
出处
《气象与环境学报》
2007年第5期1-7,共7页
Journal of Meteorology and Environment
基金
"十五"国家科技攻关计划课题"奥运气象保障技术研究"(2002BA904B05)
2002年北京市重大科技计划项目"奥运会气象保障科学技术试验与研究"(H020620190091)
"十五"国家科技攻关计划课题奥运科技专项"北京奥运会国际天气预报示范计划关键技术研究"(2003BA904B08)共同资助
关键词
对流性天气
气候背景
冰雹
暴雨
大风
Convective weather
Climate background
Hail
Rainstorm
High wind
