1961—2010年蒸发皿蒸发量气候变化特征及影响因素研究——以蒙阴县为例

Climate Change Characteristics and Influence Factors of Pan Evaporation from 1961 to 2010:Taking Mengyin County for Example

以蒙阴气象站1961—2010年逐日气象观测数据为基础,采用相关分析和小波分析方法对蒙阴近50年来蒸发皿蒸发量及其主要影响因子(日照、气温、气温日较差、相对湿度和风速等)进行了相关性及趋势性分析。结果表明:近50年来,蒙阴年平均蒸发皿蒸发量呈显著下降趋势,通过99%的置信度检验,蒸发皿蒸发量的下降主要表现在夏、春、秋3季,夏季最为明显,20世纪80年代初期蒸发皿蒸发量发生了由多到少的突变;蒸发皿蒸发量变化具有21.1年时间尺度的周期性变化;蒸发皿蒸发量减少的主要原因是日照时数、气温日较差和风速的显著减少以及水汽压的增加所致。

Based on the daily meteorological data of Mengyin Meteorological Station from 1961 to 2010 ,correlation analysis and wavelet analysis method were used to analyze the change trend of pan evaporation in Mengyin during recent 50 years, as well as the correlation with its impact factors （sunlight, temperature, daily range of temperature, relative humidity and wind speed）.The results showed that in the recent 50 years ,the average annual pan evaporation showed a significant downward trend in Mengyin,which reached 99% level of confidence test;the average annual pan evaporation decreased mainly in summer, spring and autumn, the trend was the most obvious in summer, which reached 99% level of confidence test. In the early period of 1980s, pan evaporation changed suddenly from more to less.The change period of pan evaporation was 21.1a.The main reason for the decrease of pan evaporation were the significant decrease of sunshine hours, daily range of temperature and wind speed, and also the increase of water vapor pressure.