利用邕江洪峰水位、年最高水位资料及邕江流域气象测站逐月降雨量资料,对邕江洪水的特征进行分析表明,洪水多数发生在华南后汛期7～9月,并与流域夏季降雨量密切相关。利用NCEP/NCAR再分析资料以及NOAA卫星观测的OLR资料,分析邕江洪水形成的天气气候条件,研究结果表明:热带气旋影响是邕江发生洪水的主要原因。当西太平洋副热带高压位置偏北,邕江流域易受热带辐合带(ITCZ)影响,对流活跃,热带气旋活动频繁,此时邕江易发生洪水;地形对邕江洪水的形成有较重要的作用;邕江洪水易发生在赤道东太平洋海温为负距平的条件下。分析了邕江洪水气候成因。
The analysis of the characteristics of flood in the Yongjiang River shows that the floods almost occur in July-September,the later rainy season in the southern China,and its variations correlate closely to the summer precipitation in the Yongjiang River drainage area by using the data sets of the flood peak and the annual highest water levels of the river,and the monthly precipitation over every observatory in the river drainage area.In this work,we analyse the climatic conditions causing flood in the Yongjiang River based on the NCEP/NCAR reanalysis data and the Outgoing Longwave Radiation(OLR) data.The results are as follows:(1) The flood in the Yongjiang River is mainly caused by Tropical Cyclones.When the West Pacific Subtropical Anticyclone is more northward than usual,ITCZ(intertropical convergence zone) can more easily affect the Yongjiang River drainage area,associating with the frequency of Tropical Cyclones and the activity of convection.(2) Landform makes an important contribution to the flood of the Yongjiang River.(3) The flood occurs easily in negative sea surface temperature anomalies(SSTA) over the eastern equatorical Pacific.We also analyse the variation of the synoptic systems cuasing the flood,and changes of the annual highest water levels in the condition of climate warming to futher realize the climatic reasons causing the flood.
[1] 吴兴国,杨望月,黄治逢,等.郁江南宁段致洪气象特征分析[J].广西气象,1999,20(4):7～10.
[2] 孙力,安刚,丁立.中国东北地区夏季旱涝的分析研究[J].地理科学,2002,22(3):311～316.
[3] 俞日新,陈顺天,班英华,等.广西水旱灾害及减灾对策[M].南宁:广西人民出版社,1997.67～131.
[4] 李维京,赵振国,李想,等.中国北方干旱的气候特征及其成因的初步研究[J].干旱气象,2003,21(4):1～5.
[5] 解明恩,程建刚.云南气象灾害特征及成因分析[J].地理科学,2004,24(6):721～726.
[6] 冯利华.江淮流域大洪水的发生规律探讨[J].地理科学,2000,20(5):427～430.
[7] 李崇银.气候动力学[M].北京:气象出版社,2005.133～326.
[8] 蒋尚城,张卫东.OLR揭示的北太平洋副热带高压的气候学特征[J].地理研究,1994,3(2):27～33.
[9] 丁一汇.高等天气学[M].北京:气象出版社,2005.492～538.
[10] 刘南威,杨士弘,刘洪杰,等.自然地理学[M].北京:科学出版社,2005.241～263.
[11] 罗潋葱,秦伯强,朱广伟.太湖流域上游降水特征分析[J].地理科学,2004,24(4):472～476.
[12] 王绍武,赵宗慈,龚道溢,等.现代气候学概论[M].北京:气象出版社,2005.149～158.
[13] 冯利华.长江巨洪前期物理因子配置[J].地理科学,2002,22(4):504～506.
[14] 唐晓春,刘会平,潘安定,等.广东沿海地区近50年登陆台风灾害特征分析[J].地理科学,2003,23(2):182～187.
[15] 李加林,王艳红,张忍顺,等.海平面上升的灾害效应研究——以江苏沿海低地为例[J].地理科学,2006,26(1):87～93.
[16] 陈宁生,张飞.2003年中国西南山区典型灾害性暴雨泥石流运动堆积特征[J].地理科学,2006,26(6):701～705.
[17] 谢远云,李长安,王秋良,等.江汉平原近3 000年来古洪水事件的沉积记录[J].地理科学,2007,27(1):81～84.
[18] 徐海量,叶茂,宋郁东.塔里木河源流区气候变化和年径流量关系初探[J].地理科学,2007,27(2):219～224.
[19] 朱西德,王振宇,李林,等.树木年轮指示的柴达木东北缘近千年夏季气温变化[J].地理科学,2007,27(2):256～260.
[20] 赵景波,蔡晓薇,王长燕.西安高陵渭河近120年来的洪水演变[J].地理科学,2007,27(2):225～230.
[21] 刘晓清,赵景波,于学峰.清代泾河中游地区洪涝灾害研究[J].地理科学,2007,27(3):445～448.
[22] 郭志梅,缪启龙,李雄.中国北方地区近50年来气温变化特征的研究[J].地理科学,2005,25(4):448～454.
[23] 王绍武,蔡静宁,朱锦红,等.近千年全球平均气温变化的诊断与模拟研究[A].见:黄荣辉.我国旱涝重大气候灾害及其形成机理研究[C].北京:气象出版社.2003.459～466.
