1957-2017年腾格里沙漠的风速时空特征

Spatial-temporal characteristics of wind speed in the Tengger Desert from 1957 to 2017

基于腾格里沙漠地区1957-2017年的气象观测资料,对风速的时间变化特征、突变时间、时空结构与空间分布特征展开分析.结果表明,腾格里沙漠地区60 a平均风速为2.64 m/s,总体呈显著下降趋势,下降速率约为0.07 m/(s·10 a);风速存在明显的年代际变化特征,其中20世纪70-80年代和21世纪00-10年代是风速的2个持续下降年代,20世纪90年代是风速的短暂上升年代,20世纪80年代是风速剧烈变化的年代,风速发生显著突变;风速季节分布呈春季大、夏秋冬小的特征;风速在空间呈东高西低,北高南低分布,下降速率在空间上呈东快西慢分布.通过经验正交函数分解与旋转经验正交函数分解将腾格里沙漠地区风速变量场划分成4个变化敏感区,分别为东南部风速增大区、东北部风速快速减小区、西南部风速平稳减小区和西北部大风减小区.

Based on the meteorological observations from 1957 to 2017,the temporal variations,sudden changes,spatial-temporal structure and spatial distribution of wind speed were analyzed in this study and the results showed that the 60 a mean wind speed in the Tengger Desert region was 2.64 m/s,with an overall significant decreasing trend and a decreasing rate about 0.07 m/(s·10 a).There were obvious interdecadal variations in wind speed,with the 1970s-1980s and the 2000s-2010s being the two intervals of continuous decrease in wind speed in the region,and the 1990s a period of brief increase.The wind speed briefly increased in the 1990s.The 1980s was a period of dramatic changes,with a significant abrupt change in wind speed.The seasonal distribution of wind speed was being"high in spring and low in summer,autumn,and winter";wind speed was spatially distributed as being"high in the east and north,low in the west and south".Specially,the decline rate was distributed as being"fast in the east and slow in the west".An empirical orthogonal function analysis and rotated empirical orthogonal function analysis divided the wind speed variable field in the Tengger Desert into four areas sensitive to changes in wind speed,i.e.the southeast wind speed increasing area,the northeast wind speed fast-decreasing area,the southwest wind speed steady-decreasing area and the northwest wind decreasing area.