近50年华南地区极端强降水频次的时空变化特征  

SPATIO-TEMPORAL VARIATION CHARACTERISTICS OF EXTREMELY HEAVY PRECIPITATION FREQUENCY OVER SOUTH CHINA IN THE LAST 50 YEARS

作　　者：陆虹[1] 陈思蓉[1] 郭媛[2] 何慧[1] 徐圣璇[1] 

机构地区：[1]广西壮族自治区气候中心,广西南宁530022 [2]南京信息工程大学,江苏南京210044

出　　处：《热带气象学报》2012年第2期219-227,共9页Journal of Tropical Meteorology

基　　金：热带海洋气象科学研究基金项目"华南极端强降水变化及其对全球气候变化的响应"(200804);中国气象局气候变化专项"气候变暖背景下华南区域极端强降水研究"(CCSF-09-03);中国气象局气候变化专项"华南区域气候变化评估报告编制"(CCSF-09-11)共同资助

摘　　要：利用华南地区110个台站1961—2008年逐日降水资料,采用百分位法定义各站极端强降水事件的阈值,运用线性回归、M-K突变检验、正交函数分解(EOF)、旋转经验正交函数分解(REOF)等方法,对华南地区年极端强降水频次的时空变化特征进行分析。结果表明:在空间分布上,年极端强降水频次在华南中部较大、广东沿海和广西西部内陆较小;华南极端强降水频次有3个主要的空间异常模态,一致性异常特征是华南极端强降水频次分布的最主要空间模态,而东、西反向和南、北反向变化模态也是比较重要的异常模态。在时间分布上,华南的极端强降水事件主要发生在夏半年,夏半年极端强降水频次占全年总频次的83.7%;1960年代和1980年代极端强降水频次较少,从1980年代中后期起,极端强降水频次有由少变多的趋势。华南区域各站极端强降水频次气候倾向率不一致,除中部呈减少趋势外,其余大部呈上升趋势,华南区域各站极端强降水频次的平均序列也呈上升趋势,但上升趋势不显著。华南极端强降水频次从区域变化特征上可分为6个主要区域,分别具有不同的年际变化趋势,其中有3个区域的代表站先后发生了显著增多的突变现象。This paper comprehensively studies the spatio-temporal characteristics of the frequency of extremely heavy precipitation events over South China by using daily precipitation data of 110 stations during 1961—2008 and extremely heavy precipitation thresholds determined for different stations by REOF,trend coefficients,linear trend,M-K test and variance analysis.The results are shown as follows.The frequency distribution of extremely heavy precipitation is high in the middle of South China and low in the Guangdong coast and western Guangxi.There are three spatial distribution types of extremely heavy precipitation in South China.The consistent anomaly distribution is the main type.Reversed distribution between east and west,and between south and north is also an important type.Extremely heavy precipitation events in South China mainly occurred in the summer half year.Their frequency in summer half year accounts for 83.7% of the total frequency.In the 1960s and 1980s,extremely heavy precipitation events were less frequent while having an increasing trend from the late 1980s.Their climatological tendency rates decrease in the central and rise in the other areas of South China,and the mean series also shows an upward but insignificant trend on average at all of the stations.South China＇s frequency of extremely heavy precipitation events can be divided into six major areas;each of them shows a different inter-annual trend and representive stations in three of them experience abrupt changes by showing remarkable increases in terms of M-K tests.

关 键 词：华南 年极端强降水频次 时空变化特征 突变 

分 类 号：P407.7[天文地球—大气科学及气象学]