阿克苏流域可能蒸发量的计算

Calculation of Potential Evaporation at Akesu River Basin

利用阿克苏流域内的9个气象站的日风速、最高温度、最低温度等气象要素资料,通过彭曼-蒙特斯公式计算出气象单站的可能蒸发量,再通过采用梯度距离平方反比法(GIDS)作为差值公式计算出阿克苏流域内的每个网格点的可能蒸发量。结果表明:阿克苏流域年平均可能蒸发量约为848.3亿m3,且分布不均匀,最大值达到1 600mm,最小值约为600mm。在阿克苏流域,海拔高差变化和温、湿度是影响可能蒸发量大小的主要因素;可能蒸发量的总体变化趋势随着海拔高度的降低而逐渐增大,随着平均温度的增大而逐渐增大;阿克苏流域的可能蒸发量只是实际蒸发量的区间上限。

Based on the daily observation of meteorological elements including wind speed, maximum tempera ture as well as minimum temperature from 9 weather station at Akesu basin, the potential evaporation at each grids of the whole basin are calculated through using GIDS （Gradient Inverse Distance Spuared） as Penman-Monteith equation. It is concluded that, the annually averaged potential evaporation of Akesu basin is approximately 84.83 billion cubic meters, the distribution of which is uneven, with its maximum 1 600 mm and minimum around 600 mm. The dominant factors for potential evaporation are the variation of sea level elevation, temperature and humidity. Meanwhile, the general changing tendency of the potential evaporation increased gradually with the decreasing of sea level elevation and the increasing of mean temperature, and the potential evaporation of Akesu basin is just the interval upper limit of the actual evaporation.