基于Morlet小波分析的云贵高原区春季降水特征研究

An Analysis of Spring Precipitation in Guizhou Province Based on Morlet Wavelet Method

春季是农业生产的重要季节,春季降水直接影响着农业生产。以处于云贵高原区的贵州省为例,利用1961-2013年19个气象站点逐日降水资料,在Matlab、Suffer等软件支持下,采用线性倾向估计法、morlet小波分析,研究贵州春季降水变化趋势、降水振荡和周期变化规律。结果表明:(1)整体上,研究区近53 a春季降水呈下降趋势,20世纪80年代中期以前,降水偏多,80年代中期以后,降水偏少;遵义地区春季降水减少最显著,凯里地区降水减少最缓慢。(2)整个研究区春季平均降水量为297 mm,毕节地区平均春季降水量最少,只有约190 mm,铜仁地区平均春季降水量最多,达到403 mm。(3)整个研究区和典型研究区春季降水都存在着明显的周期变化规律,长周期强于短周期,各区域代表站春季降水量较活跃的主要有25、32、28~32 a振荡周期。

Spring is an important season for agricultural production. This paper takes Guizhou Province in the Yunnan-Guizhou Plateau as an example. In this paper,daily precipitation in 19 weather stations in Guizhou Province from 1961 to 2013 were studied by using software such as MATLAB,and suffer,and Morlet wavelet analysis with linear trend method,research on Guizhou spring oscillations and cycles of precipitation change trend and precipitation changes. According to the research results,the precipitation in the study area has,on the whole,been decreasing in the past 53 years. Before the mid-1980 s,precipitation was more than that in the mid-1980 s. However,the precipitation was less than that in the mid-1980 s. The precipitation in Zunyi decreased significantly in spring and the precipitation in Carey was the slowest. The average spring rainfall in the entire study area was 297 mm,with the average spring rainfall in Bijie being the least,only about190 mm. The average spring rainfall in Tongren Area reached the maximum of 403 mm. There are obvious periodic variations of spring precipitation in the whole research area and the typical research area. The long period is stronger than the short period,and the spring precipitation in each area is mainly active in 25 a,32 a and 28 - 32 a.