遵义西北部日照时数变化特征

Variation Characteristics of Sunshine Duration in the Northwest of Zunyi

选取遵义市西北部桐梓、习水和遵义3站过去56-61 a的日照时数,采用Mann-Kendall检验法和R/S法,对全年及四季日照时数的变化特征及趋势进行分析。结果表明,除习水秋季日照时数外,其余站点年和季节日照时数均呈减少趋势,其中夏季及全年减少趋势最显著,且遵义日照时数的下降趋势总体高于习水和桐梓。夏季及全年日照时数Hurst指数在0.7039～0.7998之间,预示研究区未来日照时数将持续减少。

Based on the monthly sunshine duration from three meteorological stations in Tongzi, Xishui and Zunyi of the northwestern Zunyi in the past 56-61 years, the temporal distributions and trend of sunshine duration were analyzed by using the Mann-Kendall test and Rescaled Range Analysis. The results showed that the annual and seasonal sunshine duration had a decreasing trend except for autumn sunshine duration in Xishui, and the decreasing trend of three stations in summer were most obvious,. And the decreasing rate of sunshine duration in Zunyi was more than that in Xishui and Tongzi. The Hurst index of annual and summer sunshine duration was 0.7039 to 0.7998, which indicates the sunshine duration will likely continue to decrease in the future in higher probability.