基于1960-2012年云南省25个气象站点观测的气象数据,用Penman-Monteith公式计算参考作物蒸发蒸腾量ET0,通过Mann-kendall检验法进行突变检验和趋势检验。结果表明滇中、滇东北、滇东南、滇西南及滇西北各分区多年平均ET0介于872.5~1 240.0mm,突变时间依次分别为1982年、1968年和2008年、1971年、2005年、1965年和2001年。5个区多年平均ET0按从大到小排列的顺序是滇中〉滇西南〉滇东北〉滇东南〉滇西北。时间尺度上,年均ET0以没有显著变化为主,ET0显著增大的站点数量比显著减小的站点数量多;春季蒸发蒸腾量较大,决定了全年蒸发蒸腾量的分布特征。空间尺度上,ET0呈增加趋势的站点主要位于滇西南和滇西北地区,少部分位于滇中地区的东部和滇东北地区;呈减小趋势的站点主要位于滇中地区,少部分位于滇东北和滇西南地区。
Based on the meteorological data of 25 stations in Yunan Province from 1960 to 2012, reference crop evapotranspiration (ETo) was estimated with the FAO Penman-Monteith formula and the variations of ETo were analyzed by Mann--Kendall test. The results showed that the average ETo in Yunnan Province ranged from 872. 5 millimeters to 1 240 millimeters. In central Yunnan, Northeastern Yunnan, Southeastern Yunnan, Southwestern Yunnan and Northwestern Yunnan, the abrupt change of ETo respec- tively occurred in 1982, 1968 and 2008, 1971, 2005, and 1965 and 2001. In addition, the ETo in spring contributed most of a year. There was no significant temporal change and stations where ETo significantly increased outnumbered stations where ETo significant- ly decreased. Most of the stations where ETo increased were located in the Southwestern Yunnan and Northwestern Yunnan, and the rest were located in Northeastern Yunnan and the east of central Yunnan. Most of the stations where ETo decreased were located in central Yunnan, and the rest were location in Northeastern Yunnan and Southwestern Yunnan.