基于功率谱的扎龙湿地降水周期分析

Analysis of precipitation cycles in zhalong wetland based on power spectral

降水等时间序列往往存在周期性波动的特征,其周期的识别和提取通常采用谱分析方法从频域角度进行分析。基于谱分析中的功率谱原理对扎龙湿地1951~2008年的降水时间序列进行分析。结果表明,该地区存在3年左右的降水周期;研究也表明功率谱对于短周期的识别比较稳定和准确,最大时滞主观选择的不同会造成不同长周期的识别和提取,产生虚假的周期。

The cycle of time serial such as precipitation is always identified and extracted in the frequency domain through the method of spectral analysis because of periodic fluctuation. Based on the principle of power spectral, this paper analyzed the time serial of precipitation in zhalong wetland from 1951 to 2008. The results showed that there were precipitation cycles of about 3 years in the area;The study also showed power spectral analysis was stable and accurate if the period was short, but if the cycle was long it had different identification and extraction because of the subjective choice of maximum time-delay so that the false period occurred.