【作者】 时兴合； 李凤霞； 扎西才让； 郭安红； 达成荣； 唐红玉；

【Author】 Shi Xing-he 1,2 Li Feng-xia 3 Zha Xi-cairang 1 GuoAn-hong4 Da Cheng-rong 1 Tang Hong-yu1(1.The province meteorological station of Qinghai,Qinghai Xining 810001,China;2.Laboratory for Climate Study China Meteorological Administration,Beijing 100081,China;3.The province meteorological science Institute,Qinghai Xining 810001,China;4.Chinese Academy of meteorological Sciences,Bejing 100081,china)

【机构】 青海省气象台； 青海省气象科学研究所； 中国气象科学研究院；

【摘要】 利用1961～2004年海西东部和环青海湖地区地面气象观测资料和北半球500hPa高度场网格点资料,整理了地表积雪序列和雪灾年表,并对积雪的年代际变化特征和雪灾发生的机理及其成因进行了研究。结果表明,海西东部和环青海湖地区出现区域性雪灾的几率为15.9%(7/44),而出现局部雪灾的几率仅为9.1%(4/44)。海西东部和环青海湖40多年来冬季累计积雪量的缓慢增加易形成雪灾和低温冻害。造成该区域主要降水的影响系统是高原槽、蒙古槽和高原低涡,若后冬至春季北半球500hPa极涡中心偏向西(东)半球,青藏高原与中国东部沿海地区高度距平场形成“西低东高(西高东低)”的距平分布型时,海西东部和环青海湖地区容易出现多(少)雪年。更多还原

【Abstract】 by using grid data of 500hpa height field and the ground meteorological observation data around Qinghai Lake and over the eastern Haixi in 1961-2004,the snow disaster annual-table and ground snow sequence is collected,and the interannual variation characteristic and the appearing mechanism as well as the cause of snow disaster is studied.The result shows that the probability of appearing regional snow disaster around Qinghai Lake and over the eastern Haixe is 15.9%(7/44),while the probability of appearing local snow disaster is only 9.1%(4/44).The Qinghai Lake and over the eastern Haxi in winter in 40-year is slowly increasing of accumulated snow-cover amount is rapidly formed into snow-cover and chilling damage.The impact system of primary precipitation over this region which is caused by plateau trough,Mongolia trough and plateau low cyclone,i.e.,when the 500hpa polar vertex center of north hemisphere from winter to spring is leaning against west/east hemisphere,or the height anomaly of Qinghai-Tibet plateau and eastern coast region forms into anomaly distribution with “low in west but high in east(or high in east but low in east)”,there has more(only little) snow around Qinghai Lake and over the eastern Haixi.The variation trend of snow-cover amount in winter and spring in the future 10 years is correspond with the variation in 1990s,and which also keeps increasing.更多还原