[ Objective] To discuss regional response of reference evapotranspiration ( ETo ) to global climate change and its influencing factors. [Method] Penman-Monteith equation was adopted to calculate ET0 in Australia from 1998 to 2007. Spatiotemporal change characteristics were analyzed by using GIS spatial analysis tools and relationships between ETo and main climate factors were also analyzed. [ Resultsl The results showed that multi-year average ET0 increased from the east and south part to the northwest part and inland, and its distribution was consistent with climate zones. Multi-year average ETo of the whole region was 1 750 mm, obtaining minimum and maximum values in 2000 and 2002 respectively. Regional ETo decreased in the order of summer, spring, autumn and winter; January and December got the highest monthly ET0, while June got the lowest value 79.55 mm. ETo positively correlated with mean temperature and solar radiation, R2 for each were 0.83 and 0.94, while the relationship between ETo and average relative humidity was negative, and precipitation had no significant relationship with ET0. [ Conclusion] This research could provide important reference for crop water requirement study and making irrigation method for Australia.
蒸散量是水资源相互转化过程中非常重要但又难以定量确定的要素之一。SEBS(Surface Energy Balance System)模型是通过遥感数据计算区域蒸散量的重要模型,该模型可以在较少地面信息的情况下获得蒸散量的区域分布信息,同时具有较高的精度。采用SEBS模型,利用NOAA/AVHRR数据对我国重要的商品粮基地三江平原区域蒸散发量进行了研究,并通过实测数据对估算结果进行了验证。结果表明:从时间分布来看,三江平原蒸散量总体上表现为从4月开始逐渐上升,7月达到最高值,8月后不断下降。在此基础上,探讨了三江平原蒸散量时间分布的原因。同时,结合研究区的土地利用类型,对三江平原区域蒸散量空间分布进行了分析,各种土地利用类型生长季平均蒸散量从大到小可以排列为:林地>水域>湿地>水田>旱田>草地>居工地。