沙漠与绿洲气象
沙漠與綠洲氣象
사막여록주기상
DESERT AND OASIS METEOROLOGY
2015年
2期
24-30
,共7页
短时强降水阈值%强降水事件%强降水雨强
短時彊降水閾值%彊降水事件%彊降水雨彊
단시강강수역치%강강수사건%강강수우강
threshold value of short time heavy rainfall%short time heavy rainfall events%rain intensity of heavy rainfall
基于1991—2013年呼伦贝尔市汛期(6—8月)16站逐小时降水资料,分别定义各站点小时降水量的短时强降水阈值,同时利用经验正交函数(EOF)分析方法揭示呼伦贝尔市短时强降水(强降水)变化特征。分析结果表明:强降水阈值、强降水事件以及强降水雨强均呈现自西向东部偏南方向递增的空间分布,最强中心位于东南部阿荣旗,其形成与地形关系密切。强降水占汛期总降水量百分比低于1/5,而且发生频率最低的地区出现84.2 mm/h的强降水事件。强降水事件具有明显年代际变化,21世纪10年代以来,强降水事件发生频率增加趋势明显,空间分布表现为自东北向西南方向传播。7月下旬是强降水事件频发的时段,而且有明显日变化特征,主峰出现在17时。EOF分析结果显示强降水事件在空间上表现出全市具有同步性以及南部和北部地区反相位的特征。
基于1991—2013年呼倫貝爾市汛期(6—8月)16站逐小時降水資料,分彆定義各站點小時降水量的短時彊降水閾值,同時利用經驗正交函數(EOF)分析方法揭示呼倫貝爾市短時彊降水(彊降水)變化特徵。分析結果錶明:彊降水閾值、彊降水事件以及彊降水雨彊均呈現自西嚮東部偏南方嚮遞增的空間分佈,最彊中心位于東南部阿榮旂,其形成與地形關繫密切。彊降水佔汛期總降水量百分比低于1/5,而且髮生頻率最低的地區齣現84.2 mm/h的彊降水事件。彊降水事件具有明顯年代際變化,21世紀10年代以來,彊降水事件髮生頻率增加趨勢明顯,空間分佈錶現為自東北嚮西南方嚮傳播。7月下旬是彊降水事件頻髮的時段,而且有明顯日變化特徵,主峰齣現在17時。EOF分析結果顯示彊降水事件在空間上錶現齣全市具有同步性以及南部和北部地區反相位的特徵。
기우1991—2013년호륜패이시신기(6—8월)16참축소시강수자료,분별정의각참점소시강수량적단시강강수역치,동시이용경험정교함수(EOF)분석방법게시호륜패이시단시강강수(강강수)변화특정。분석결과표명:강강수역치、강강수사건이급강강수우강균정현자서향동부편남방향체증적공간분포,최강중심위우동남부아영기,기형성여지형관계밀절。강강수점신기총강수량백분비저우1/5,이차발생빈솔최저적지구출현84.2 mm/h적강강수사건。강강수사건구유명현년대제변화,21세기10년대이래,강강수사건발생빈솔증가추세명현,공간분포표현위자동북향서남방향전파。7월하순시강강수사건빈발적시단,이차유명현일변화특정,주봉출현재17시。EOF분석결과현시강강수사건재공간상표현출전시구유동보성이급남부화북부지구반상위적특정。
Base on the hourly precipitation data collected from 16 stations during the rainy reason (from June to August)over Hulun Buir city from 1991 to 2013, a threshold value was defined for each stations by the method of threshold value and characteristics of short time heavy rainfall (STHR) were analyzed by Empirical Orthogonal Function (EOF) analysis methods . The results show: The spatial distribution characteristic of the threshold value, events and rain intensity of STHR decrease from west to southeast, the strong center area is in Arongqi of the southeast of Hulun Buir and the spatial distribution characteristic of STHR is the closest relationship with the terrain. The total precipitation of STHR is lower 1/5 than the total precipitation of the rainy season. There appears maximum hourly rainfall of 84.2 mm/h over the inactive areas of STHR events. STHR events experience obviously inter-decadal variation, It founds that the frequencies of STHR obviously increase and move from northeast to southwest after 2010s. STHR events frequently occur in late July and have diurnal variations. the most active diurnal peak is 17:00. The EOF analysis results indicate that STHR events consistent over the whole Hulun Buir and has opposite phases in the south and the north areas.