深圳市近57年来降水时空演变特征分析

Tempo-spatial changes of precipitation of Shenzhen in last 57 years

分析区域降水的时空演变特征,对了解区域水文水资源未来情势变化、制定科学的水资源利用和防汛抗旱决策具有重要意义。基于1960—2016年共57年深圳市水文测站降水量系列资料,采用经验正交函数分解分析了深圳市年降水量的空间分布特征,并借助Mann-Kendall,Spearman非参数检验、累积距平和小波分析等多种方法,从趋势变化、突变特征和周期波动等方面研究年降水量时程演变特征,初步分析了变化成因。研究结果表明:57年来深圳市年降水量空间上具有较明显的两种分布型态,时程上不存在显著的趋势变化,但在局部时段上呈现出以1991年或2004年前后为突变点、先降后升的阶段性变化;深圳市年降水量普遍存在17~20年、5~7年的显著准周期,未来深圳区域年降水量在2016年之后将会维持一段时间的偏丰状态。

It is of great significance to understand the change rules of the precipitation for predicting the regional water resources situation changes in the future and formulating the decisions of water resources utilization and flood control. Based on the precipitation observation data obtained from 1960 to 2016 in Shenzhen, the comprehensive analysis of the tempo-spatial variation characteristics of the precipitation over the area, such as the spatial variation, the long-term trends, the break point and orthogonal function decomposition （EOF）, the periodic oscillations, etc, is carried out by using the empirical the cumulative anomaly curves, the Mann-Kendall and the Spearman nonparametric testing and the Morlet continuous wavelet analysis. The research resuhs show that the annual p^cipitation in Shenzhen has two distinct spatial distribution patterns in the past 57 years, and there is no significant change trend in the time history of the precipitation, but in the local period, the precipitation shows a sudden change in 1991 or 2004, and showing a gradual change after falling first and then rising. The analysis results also show that the annual precipitation in Shenzhen generally has a significant quasi period of 17-20 years and 5-7 years. In the future, the annual precipitation in Shenzhen will remain at a high level for some time after 2016.