【摘要】 利用西北脆弱带40个气象站点1961—2015年降水量数据资料,采用趋势线拟合、线性倾向估计、普通Kriging插值等数理分析方法,对西北脆弱带近54年的降水量季节变化特征进行了分析。结果表明:(1)随着全球变暖趋势越来越明显,西北脆弱带近54年间降水量总体呈减少趋势;(2)该区年均降水量空间变化大致是沿东南—西北方向呈现由多到少的过渡,年均降水量倾向率空间变化则大致沿东南—西北方向呈现由减少到增加的逐步过渡;(3)该区54年间四季降水距平变化趋势为春、夏、冬三季的降水量呈增加趋势,秋季降水量呈减少趋势,变化速率为夏季>冬季>春季>秋季。四季降水量的空间差异明显,大致都沿东南—西北方向呈现由多到少的逐步过渡趋势。更多还原

【Abstract】 Based on the data of 40 national meteorological stations in northwest vulnerable ecotone from 1961 to 2015,the characteristics of spatial-temporal variation of precipitation in the past 54 years were analyzed by using linear trend estimation,Mann Kendall mutation test,ordinary Kriging interpolation mathematical analysis methods.The results showed that:(1)the precipitation in the 54 years decreased in northwest vulnerable ecotone as a whole since the global warming trend was more and more obvious;(2)the spatial variation of annual precipitation reduced roughly from the southeast to northwest,and the tendency rate of annual precipitation reduced gradually at first then increased from the southeast to northwest;(3)the change trend of anomaly in this area from 1961 to 2015 showed that the precipitation increased in spring,summer and winter,however,it reduced roughly in autumn,and the change rate of precipitation followed the order:winter>spring>autumn>summer,the spatial distribution characteristics of precipitation in the four seasons were obvious,which reduced gradually from the southeast to northwest.更多还原