广东蒸发皿蒸发量的季节变化特征及其影响因素的灰色关联分析

Variations of Seasonal Pan Evaporation and Gray Relation Analysis on Its Influencing Factors in Guangdong

为了研究广东省的气候变化规律及其成因,利用1961—2003年广东省86个气象站点的观测数据,采用Mann-Kendal非参数检验方法、EOF经验正交分解方法和灰色关联分析方法,对广东省近43 a来蒸发皿蒸发量及其主要影响因子(日照时数、风速、降水量、饱和差、气温日较差、气温等)进行了相关性及趋势性分析。结果表明:43 a来广东省的季蒸发皿蒸发量的下降主要表现在春季、前汛期和后汛期,其减少趋势通过或接近通过99%置信水平的统计检验,而秋季的变化不明显;四季蒸发皿蒸发量的下降主要表现在粤东沿海、珠三角和粤西南等沿海地区,不同季节气候变异中心的位置不同;日照时数下降以及风速、气温日较差的减小可能是近年来广东四季蒸发皿蒸发量下降的主要原因。

In order to explore the law of climate change and its causes in Guangdong Province, based on the observations at 86 stations of Guangdong from 1961 to 2003, Mann-Kendall trend test, EOF analysis and Gray relation analysis were applied to determine the trend of seasonal pan evaporation and its corre- lations with the meteorological influencing factors （e. g. sunshine duration, wind speed, precipitation, saturation deficit, daily range of temperature, air temperature, etc. ）. Results show that the seasonal pan evaporation had significant decreasing trends in spring, the first rain season and the latter rain season in the last 43 years, with statistical significance passing the 99% confidence level, but the trend was not significant in autumn. Spatially, the anomalous centers of seasonal pan evaporation were mainly located in the Pearl River Delta, the south-west of Guangdong and the eastern coastal region of Guangdong, and the anomalous centers were different in different seasons. The decrease of seasonal pan evaporation was mostly resulted from reduction of sunshine duration, wind speed and daily range of temperature in Guangdong.