摘要
为了解兰州市降水量的变化特征,利用兰州气象站1951—2015年月降水量序列数据,采取线性倾向估计法、滑动平均法、累积距平法、Mann-Kendall非参数检验法及Morlet小波分析等方法分析兰州市近65年来年降水量及各季降水量的变化特征。研究结果表明:近65年来兰州市年降水量总体呈波动式下降趋势,倾向率为-8.20 mm/10年。4季中除冬季降水量呈略微上升趋势外,其余3季降水量均与年降水量变化趋势相同,呈波动式下降趋势。年降水量于1979年发生由增多至减少的突变,各季降水量变化同样存在若干突变点。兰州市降水量变化存在多时间尺度效应,其中年降水量变化的第一、第二及第三主周期分别为46年、32年及14年。目前处于第一主周期降水偏丰阶段,且在未来5~7年内仍将处于偏丰状态。研究成果可为兰州市农业生产活动提供一定的科学依据。
In order to find out the variation characteristics of precipitation in Lanzhou, the variation characteristics of the annual and all the seasonal precipitations of Lanzhou since recent 65 years are analyzed herein with the linear tendency estimate method, moving average method, accumulative anomaly method, Mann-Kendall nonparametric test method and Morlet wavelet analysis method according to the monthly precipitation series data from 1951 to 2015 recorded by Lanzhou Meteorological Station. The study result shows that the annual precipitations of Lanzhou since recent 65 years are generally present fluctuated downtrends with the tendency rate of - 8.20 mm/10 a. Except a little rising trend of the precipitation from winter within the four seasons, the variation trends of the precipitations in the other three seasons are the same with that of the annual precipitations and show the fluctuated downtrends. A sudden change from increase to decrease of the annual precipitation occurs in 1979, while several sud- den change points exist in the variations of the precipitations in all the seasons. A multi-time scale effect is there in the variation of precipitation of Lanzhou, in which the first, second and third main cycles of the annual precipitation variations are 46, 32, and 14 years respectively. At present, it is in a more rich precipitation phase of the first main cycle, and the status of the more rich precipitation is to exist in the next 5 - 7 years yet. The study result can provide a certain scientific basis for the agricultural production activities in Lanzhou.
出处
《水利水电技术》
CSCD
北大核心
2017年第4期8-12,共5页
Water Resources and Hydropower Engineering
基金
庆阳市科技局青年科技基金项目(ZJ2014-08)
西峰区科技局科技合作基金项目(XK2016-20)
