乐陵市蒸发量变化特征分析

ANALYSIS ON CHARACTERISTICS OF EVAPORATION CHANGES IN LELING

利用乐陵市气象局1961～2010年小型蒸发皿资料,对蒸发量的年、季、月变化趋势、变化特征和突变等气候变化作了较全面分析。结果表明:50年来各季、月蒸发量呈现不同程度的减少趋势,年蒸发量以-18.9 mm/a的倾向率减少,减少趋势主要表现在夏季、春季,其中5、6月份蒸发量减少趋势最明显。年蒸发量在20世纪60、70年代为相对偏多期,80年代以后为相对偏少期。采用累积距平曲线对年总蒸发量进行突变检验表明,年蒸发量在1983年发生一次突变。

According to the evaporation statistics released by Leling meteorological bureau in 1961 -2010 ,a com- prehensive analysis was made about the evaporation variation trend, change characteristics and its mutation. The result showed that each month＇s and each season＇s evaporation presented different degree of the decreasinging trend. The annual evaporation reduced at a trend rate of 18.9/a mainly in summer and spring, especially in May and June. It was comparatively more in the 1960s and 1970s and few after the 1980s. Using the accumulated curve surface, the year＇s total evaporation was inspected and it showed there was a mutation in 1983.