1981—2022年福建省降雨集中度和集中期时空变化特征分析

Temporal and spatial variation characteristics of rainfall concentration degree and concentration period in Fujian Province from 1981 to 2022

为研究福建省降雨集中度和集中期时空分布特征和变化规律,利用福建省内25个气象站点1981—2022年的逐日降雨量资料,根据降雨集中度和集中期模型,采用克里金插值法和Mann-Kendall非参数检验法和小波分析等方法研究福建省降雨集中度和集中期的时空分布规律。结果表明:福建省降雨集中度空间分布呈现由西北向东南递减特征,降雨集中期空间分布由东北向西南递减,集中期较早,长期趋势上看集中度表现为上升趋势,集中期表现为下降趋势,集中度和集中期在20世纪90年代末发生突变,集中度和集中期都存在26年左右的显著周期,在1995—2010年存在10年左右的相同周期。1981—2022年福建省降雨集中度缓慢增加,集中期提前,预计未来福建省降雨有趋于集中的态势,应重点防范夏季降雨造成的洪涝灾害。

In order to study the spatiotemporal distribution characteristics and change rules of rainfall concentration degree and concentration period in Fujian Province,the daily rainfall data from 25 meteorological stations in Fujian Province from 1981 to 2022 were used to study the spatiotemporal distribution rules of rainfall concentration degree and concentration period in Fujian Province by using Kriging interpolation method,Mann-Kendall nonparametric test method,and wavelet analysis methods based on rainfall concentration degree and concentration period models.The results show that the spatial distribution of rainfall concentration in Fujian Province presents a downward trend from northwest to southeast,and the spatial distribution of rainfall concentration periods decreases from northeast to southwest.The concentration period is earlier.In the long-term trend,the concentration degree shows an upward trend,while the concentration period shows a downward trend.The concentration degree and concentration period undergo a sudden change in the late 1990s,and there is a significant cycle of about 26 years for both the concentration degree and concentration period,In 1995—2010,there was a similar cycle of about 10 years.From 1981 to 2022,the rainfall concentration in Fujian Province increased slowly and the concentration period was advanced.It is expected that the rainfall in Fujian Province will tend to be concentrated in the future.Therefore,it is necessary to focus on preventing floods caused by summer rainfall.