基于云模型的四川省潜在蒸散量时空分布研究

Analysis on Characteristics of Temporal-spatial Potential Evapotranspiration Distribution in Sichuan Based on Cloud Mode

为了研究四川省潜在蒸散量(ET0)的时空分布特性,利用FAO-56 Penman-Monteith方法计算四川省4个分区45个站点1960—2010年51 a潜在蒸散量(ET0),首次采用云模型描述ET0的时空分布特性。结果表明:51 a来四川省ET0先减小,2000年后有增加的趋势;4个分区ET0在时间上分布都不均匀,四川盆地、盆周山地和川西南山地的不均匀性较川西北高原稳定。ET0的空间分布较时间分布更不均匀,不均匀性更加不稳定。川西南山地区的多年平均ET0最大,川西北高原次之,四川盆地和盆周山地较小。ET0空间分布的不均匀性在这51 a先增强,2000年后有所减弱。1991—2010年ET0空间分布不均匀性的稳定性较前30 a减弱,但2000年后稳定性有增强的趋势。

The FAO -56 Penman-Monteith method was used to calculate the potential evapotranspiration （ ET0 ） from 1960 to 2010 in 45 stations in Sichuan. Then the cloud model was firstly applied to analyze the temporal-spatial variation characteristics of ETo. Results showed that from 1960 to 2010, ETo has firstly decreased then increased after 2000. The temporal distribution ofET0 is dispersive in the four areas. The dispersion in Siehuan basin, mountainous areas around basin and southwestern mountain area is more stable than that in northwest plateau. The spatial distribution of ETo is more dispersive and unstable than the temporal distribution. The mean annual ETo in southwestern mountain area is highest, followed by northwest plateau, Sichuan basin and mountainous areas around basin. The spatial dispersion ofETo has firstly enhanced,then weakened after 2000. The spatial dispersion ofETo from 1991 to 2010 is less stable than that from 1960 to 1990,but the stability has been enhanced after 2000.