新疆主要城县1993—2013年极大风速时空变化特征分析

Temporal and Spatial Variation of Maximum Wind Speed in Xinjiang:of Main Cities and Counties During 1993 to 2013

大风在地表裸露的沙尘源地及其附近形成沙尘暴灾害,使土壤风蚀、沙化,增加沙尘频次和恶化空气质量,破坏生态环境,危害农业生产。因此,深入研究生态环境相对脆弱的新疆地区的极大风速风向特征,对于防灾减灾,治理活化沙丘及实现本区的可持续发展具有十分重要的意义。以新疆地区71个站点的最新资料为基础,探究新疆地区1993—2013年极大风速的时间演变现象和空间分布特征,给出新疆地区年、月极大风速出现日数的分布及风速方向特征。研究得出:1993—2013年间乌恰县风速大于17 m/s的日数最多,和田市最少;总共16天。极大风速日数最高值出现在1999年,全疆总大风日为257天;最低值在2013年,全疆总大风日为69天。春夏季大风日数大于秋冬季。新疆主要城县极大风速方向有明显差异,天山以东主要为东南、东北方向;天山以北主要为西北、东北方向;天山以南主要为东北、西北方向;天山以西主要为东南、西北方向。

Sandstorms are formed around the surface of exposed dust sources by wind, which make soil drifting and desertification, increase the frequency of dust storms and deteriorate air quality, damage the ecological environment and agricultural production. Therefore, it is quite important to study the characteristics of maximum wind speed and wind direction in Xinjiang, whose ecological environment is relatively fragile, and the study is of great significance to the disaster prevention and reduction, the management of activated dune and sustainable development. Based on the latest data of 71 sites in Xinjiang, we explored the temporal evolution and spatial distribution of maximum wind speed from 1993 to 2013, and analyzed the distribution of annual and monthly maximum wind speed and the characteristics of wind direction. The results showed that Ulugqat county had the most maximum wind speed(>17 m/s) days from 1993 to 2013, and the number of days in Khotan was the minimum of 16 days. The highest value of maximum wind speed days appeared in 1999,totally 257 days in Xinjiang;the lowest was in 2013 of 69 days. Spring and summer wind days were greater than that of autumn and winter. There were obvious differences in the direction of the maximum wind speed inmajor cities and counties of Xinjiang. The maximum wind speed in the east of Tianshan Mountain was mainly southeast and northeast direction, that in the north of Tianshan was mainly northwest and northeast direction,that in the south of Tianshan was mainly northwest and northeast direction, and that in the west of Tianshan was southeast and northwest direction.