中国天山山区潜在蒸发量的时空变化

Temporal and Spatial Changes of Potential Evaporation in Tianshan Mountains from 1960 to 2006

利用24个气象站1960-2006年的逐日气象资料,应用FAO Penman-Monteith模型,分析了天山山区潜在蒸发量的变化趋势,并在ArcGIS环境下通过IDW插值法分析了潜在蒸发量变化的空间分异,此外运用多元回归分析法对影响潜在蒸发量变化的主导因素进行了探讨。结果表明:年潜在蒸发量自60年代以来呈波状减小趋势,1986年之后减小趋势更加明显,2000年以后呈增加趋势。年潜在蒸发量的年际变化倾向率为-2.48mm/a,表明潜在蒸发量总体上呈减小趋势;从季节来看,秋季的潜在蒸发量呈增加趋势,其它季节呈减小趋势,其中春季的减小幅度最大;风速是影响潜在蒸发量变化的主导因素,影响秋季潜在蒸发量变化的主导因素是气温。

Based on the daily data of 24 meteorological stations from 1960 to 2006 and combined with the Penman-Monteith model, the changing trend of potential evaporation in the Tianshan Mountains was analyzed in this study. By the method of IDW under ArcGIS the spatial distribution of potential evaporation was drawn in order to research regional difference. And the multivariate regression method was used to discuss the dominant factor influencing potential evaporation. The results indicated that since the 1960s the annual potential evaporation has presented an undulated decreasing trend, and the decreasing trend was more evident since 1986. It began to increase since 2000. There was a decreasing trend in general because the changing rate of annual potential evaporation varied at -2.48 mm/a. The potential evaporation increased in autumn, however, decreased in other seasons especially in spring. The wind speed was a dominant factor influencing potential evaporation, while temperature was the key factor in autumn.