乌鲁木齐市近43年风速气候特征分析

利用乌鲁木齐市1961-2003年逐日平均风速资料,分析了乌鲁木齐市近43年风速的基本气候特征、变化趋势和年际、年代际变化等。其主要结果是:乌鲁木齐市年平均风速为2.47m.s-1。一年四季中夏季的平均风速最大为3.08m.s-1,冬季最小为1.52m.s-1,春季和秋季则分别为2.94m.s-1和2.31m.s-1。近43年乌鲁木齐市春季、夏季、秋季、以及年风速呈下降趋势,而冬季呈上升趋势。Morlet小波分析表明乌鲁木齐市风速变化具有准6、8年的年际尺度和准13、21年的年代际尺度周期变化,其中准13年周期振荡最为强烈。乌鲁木齐市风速变化是不同尺度周期振荡综合作用的结果。

Variation characteristics of wind velocity in Urumqi in recent 43 years

Using the day-to-day average wind velocity in Urumqi from 1961 to 2003,the basic climate characteristics,the annual and decadal periodic change of wind velocity in Urumqi in recent 43 years were analyzed.The main results were as follows:(1) The annual average wind velocity in Urumqi was 2.47m·s-1.The average wind velocity in summer was 3.08m·s-1,which was the biggest in four seasons in a year,while the average wind velocity in winter was 1.52m·s-1,which was the smallest in whole year.The average wind velocity in spring and autumn was 2.94m·s-1 and 2.31m·s-1 respectively.(2) The wind velocity in spring,summer,autumn,and a year all decreased in recent 43 years,but the wind velocity in winter increased.(3) The Morlet wavelet analysis manifested that there were inter-annual periodic variations of quasi-6 and 8 years,and inter-decadal periodic variations of quasi-13 and 21 years in Urumqi in recent 43 years.The oscillation of quasi-13 years period was the strongest.The wind velocity variation in Urumqi was the composite result of multi-scale periodic fluctuations.