贺兰山东麓暴雨环流统计预报模型  

Statistical forecast model for rainstorm circulation in eastern foot of Helan Mountain

作　　者：纪晓玲[1,2] 桑建人[1] 杨侃 穆建华 陈晓娟 张楠楠 

机构地区：[1]宁夏气象防灾减灾重点实验室银川750002 [2]宁夏气象台银川750002

出　　处：《干旱区资源与环境》2009年第8期104-109,共6页Journal of Arid Land Resources and Environment

基　　金：宁夏科技厅科技攻关项目(05GG-20503);宁夏自然科学基金(NZ07125)项目共同资助

摘　　要：利用同期NCAR/NCEP逐日全球再分析资料,以贺兰山东麓40次暴雨天气过程为研究对象,分析得到4种主要环流背景:两脊一槽、两槽一脊、一脊一槽、一槽一脊。其中,两脊一槽环流形势下发生暴雨的可能性最大,两槽一脊、一脊一槽环流形势下发生暴雨的可能性基本相当,一槽一脊较少。并对同一环流背景不同天气过程环流形势进行了合成分析,分析了贺兰山东麓暴雨环流统计模型。同时分析发现:贺兰山东麓暴雨天气70年代发生次数最多,60年代、80年代、90年代、2000年至2006年相对较少;主要发生在每年的春末到秋初,集中出现在7月、8月,其中,7月20日到8月10日为发生高频期,这与宁夏全区大降水主要出现在7月下旬到8月上旬这一发生规律是一致的。灵武到平罗一带为暴雨多发点,平罗发生频次最高,石嘴山市的石炭井发生频次最低。贺兰山大地形对其东麓强降水的发生有明显的增幅作用。By using the daily NCAR/NCEP global re - analysis data in the same time, aiming at 40 rainstorms occurred in the eastern foot of Helan Mountain, 4 types of main circulation background were obtained after analysis ： two - ridge and one - trough, twn - trough and one - ridge, bne - ridge and one - trough, and ＇one ,trough and one ridge： Among them, the possibility of the rainstorm occurrence was the biggest under the circulation situation of two - ridge and one - trough, nearly the same under the circulation situation of two - trough and one - ridge＇and ＇one -ridge and one -trough, and was relatively less under the situation of ＇one -trough and onei＇idge ： Furthermore, the statistical model of rainstorm circulation in the eastern foot of Helan Mountain was analyzed based on the synthesis analysis of circulation situations of different weather processes under the same circulation background. The analysis results showed： rainstorms occurred most frequently in the 1970s in the eastern foot of Helan Mountain, relatively less in the 1960s, 1980s, 1990s, and during 2000 -2006. They mainly occurred during the late spring to early fall in each year, concentrated in July and August, and in particular, July 20^th to August 10^th was a period with high frequency of rainstorms, it was in accordance with the rule that heavy precipitation mainly occured during the last ten - day of July to the first ten - day of August in Ningxia whole region. Lingwu to Pingluo was the area where rainstorm occurred most, Pingluo had the highest frequency while Shitanjin of Shizuishan city had the lowest frequency of rainstorms. The large - scale terrain of Helan Mountain had obvious increase effect upon the occurrence of heavy precipitation in the eastern foot of it.

关 键 词：暴雨 环流 统计模型 地形作用 时空分布 贺兰山东麓 

分 类 号：P426.62[天文地球—大气科学及气象学]