1961—2015年辽宁地区参考作物腾发量变化特征

Variation characteristics of reference crop evapotranspiration in Liaoning province from 1961 to 2015

利用1961—2015年辽宁地区50个气象站点的逐日气象观测数据,采用Penman-Monteith公式计算辽宁地区参考作物腾发量,利用数理统计、R/S分析法和M-K检验分析辽宁地区参考作物腾发量的变化趋势及突变特征。结果表明:近55 a辽宁地区参考作物腾发量全年平均和四季均呈下降趋势,20世纪60—70年代参考作物蒸发量下降幅度较大,辽宁地区参考作物蒸发量总体上呈由东至西逐渐增加的空间变化特征。影响辽宁地区参考作物腾发量的主要气象要素为平均风速和日照时数,气象要素和参考作物腾发量均存在赫斯特现象,未来的气候变化趋势与过去的气候变化趋势一致,未来风速和日照时数的减小将影响参考作物腾发量持续降低。

Using the daily meteorological data from50meteorological stations in Liaoning province from1961to2015,the amount of reference crop evapotranspiration(ET0)was calculated using the Penman Monteith formulation,and its variation trend and mutation characteristics were analyzed statistically using MK(Mann Kendall)test and R/S(Re scaled Range)methods.The results show that in the recent55years,the average value of the amount of ET0in the whole year and each season presents a downward trend,with a maximum declining rate appearing during the1960s to1970s,and from east to west,it gradually increases.The average values of wind speed and sunshine hours are the main meteorological factors to influence the amount of ET0.There is a Hurst phenomenon in ET0and meteorological factors.It suggests that the variation trend in the future will be similar to the past one,i.e.,the decreasing in wind speed and sunshine hours will result in the continuously declining in ET0in the future.