主办单位:中国气象局沈阳大气环境研究所
国际刊号:ISSN 1673-503X
国内刊号:CN 21-1531/P

气象与环境学报 ›› 2013, Vol. 29 ›› Issue (3): 58-62.doi:

• 论文 • 上一篇    下一篇

1953—2010年浙西南山区降水与旱涝变化特征

吴昊旻1,2 杨羡敏1,2 姜燕敏2   

  1. 1.南京大学大气科学学院,江苏 南京 210093;2.丽水市气象局,浙江 丽水 323000
  • 出版日期:2013-06-29 发布日期:2013-06-29

Characters of precipitation, droughts and floods from 1953 to 2010 in southwest mountain area of Zhejiang province

WU Hao-min1,2 YANG Xian-min1,2 JIANG Yan-min 2   

  1. 1. College of Atmospheric Science, Nanjing University, Nanjing 210093, China; 2. Lishui Meteorological Service, Lishui 323000, China
  • Online:2013-06-29 Published:2013-06-29

摘要: 根据1953—2010年浙西南山区逐月降水资料,在对不同时间尺度降水进行气候分析的基础上,利用降水距平百分率研究年、季和月尺度上旱涝分布特征,并通过Morlet连续小波变化探讨旱涝演变趋势。结果表明:近58 a来,浙西南山区降水量和雨日均呈下降趋势,且雨日减少幅度较明显,约每10 a减少3.39 d。其中降水量以8月增多最显著,5月下降最明显;雨日则以5月和12月的减少最为突出。用Morlet小波分析得出旱涝存在不同尺度的周期分量,并且各周期强度有所不同,其中以4—8 a周期和16—20 a周期最为强烈,2010年后浙西南山区旱涝将向偏涝方向发展。年际尺度上,浙西南山区旱涝主要表现为轻旱和轻涝;季和月尺度上,以8—12月旱涝发生最为频繁,其中干旱概率多于洪涝,但洪涝强度大于干旱。

关键词: 气候学, 降水, 旱涝变化, Morlet小波分析

Abstract: Based on the monthly precipitation data from 1953 to 2010 in the southwest mountain area of Zhejiang province, the precipitation characteristics were analyzed on the different time scales. The annual, seasonal and monthly drought and flood distributions and its evolution trend were studied using methods of a precipitation anomaly percentage and a Morlet wavelet transform. The results show that the rainfall and rain day are in the decreasing trends in the southwest mountain area of Zhejiang province over the past 58 years, especially for rain day, and its decreasing rate is 3.39 days per decade. Rainfall increases in August and decreases in May significantly, while rain day decreases in May and December significantly. The drought and flood has different cycles on different scales according to a Morlet wavelet transform method, and the intensity of each cycle differs. Among all cycles, features of two cycles i.e. a 4-8 years cycle and a 16-20 years cycle are significant. It is estimated that the trend of drought and flood will develop to flood after 2010 in the southwest mountain area of Zhejiang province. It is light drought and light flood on inter-annual scale in the study area. Drought and flood mainly appears from August to December on seasonal and monthly scales. The probability of drought is higher than that of flood, while the intensity of flood is greater than that of drought.

Key words: Climatology, Precipitation, Drought and flood change, Morlet wavelet analysis