基于小波变换的楚雄市近50年降水序列多时间尺度研究

以滇中高原核心城市楚雄市为研究对象,分30个代表性气象站点1950—2009年降水时间序列,通过Morlet小波变换等方法对其进行多时间尺度研究,探讨其演变趋势和变化规律。结果表明楚雄市降水序列均呈较明显的增加趋势,对于各种时间尺度的降水序列均表现出一致的降水变化规律,传统干旱区干湿季节差异性缩小;年降水相关性最好,最大6、24 h降水量相关性非常高,短历时(即最大1、6、24 h)降水与中长时间尺度(即月、年)降水相关性最差,短历时降水对中长时间尺度降水的影响较小,区域使用的数据资料序列小于由气象资料数据序列的长度限制,说明周期性的可靠度不高,还需要进一步根据更长的序列资料进行验证。

Multi- time Scale Research on Precipitation Sequence in Chuxiong City in Recent 50 Years with Wavelet Transform

In the core city of Chuxiong City, Yunnan plateau for the study, from 1950 to 2009 time series of precipitation points 30 representative meteorological stations, and other methods by Morlet wavelet transform its multi- time scale study to explore the evolution of trends and changes in the law. The results showed that： Chuxiong City, precipitation sequence showed obvious increasing trend for precipitation sequence of various time scales have shown consistent rainfall variation, traditional wet and dry seasons arid zone differences narrowed; annual precipitation in the best correlation, the maximum 6h, 24 h precipitation correlation is very high, short duration（ ie,the maximum 1h, 6h, 24h） precipitation and the long time scale（ ie, month, year） precipitation relevance worst effects of short duration rainfall for a long time- scale precipitation small sequence regions using data from meteorological data is less than the data sequence length limit, indicating periodic reliability is not high, need to be further validated in accordance with a longer sequence data.