古尔班通古特沙漠边界层气象要素廓线观测分析

Analysis on Boundary Layer Meteorological Elements Profile in the Gurbantunggut Desert

利用2011年10月15—24日在古尔班通古特沙漠腹地系留气艇边界层试验的探测资料,分析了沙漠腹地近地层风、温、湿等气象要素廓线垂直分布特征及其变化情况,结论如下：（1）20时—08时存在逆温,08时逆温最强,逆温强度为2.85℃/100 m,逆温层高度为700 m,之后逆温逐渐消失;夜晚近地层湿度明显大于上层大气,在100 m高度差内,湿度先快速减小再缓慢增大,与白天相反,20时近地面出现逆湿,1 100 m高度湿度发生明显切变;逆温层以上风速随高度变化呈多峰态,逆温层范围内风速增大趋势明显,900-1 100 m之间存在200 m厚的恒风区,1 100 m以上风速再次增大,白天的风速小于夜间。（2）风速波动范围大约为2-8 m/s,近地面100 m范围内风速随高度快速增大,风向由东南风向南风转变,600-900 m之间风速变化减缓,风向由从南风逐渐向东风转变,以东南风为主,风速与风向同步改变。（3）600 m以下随温度升高湿度快速减小,600-1 100 m之间又持续增大,1 100-1 500 m之间呈波动变化的趋势,1500 m增大明显。（4）风切变指数夜晚大于白天,最大值在23时（20.88）,最小值在中午14时（0.97）,平均风切变指数为9.61。混合层厚度平均为125.88 m。

By Use of the detecting test datas of tethered balloon boundary layer at Gurbantunggut Desert hinterland in the autumn during 15 th to 24 th October,2011,This study Analyzed the vertical distribution characteristics of desert surface layer wind, temperature, humidity and other meteorological element profile and its changes. Conclusions were as follows：（1）Temperature inversion existed during 20：00—08：00. The top of the inversion layer is located at 700 m. The inversion rate was largest at 08：00, which was 2.85 ℃/100 m. The humidity of lower atmosphere is significantly higher than that of upper atmosphere. Humidity inversion occurred at 20：00. There was an obvious shear of the humidity at the height of 1100 m. Wind speed appeared to be rising with the height within the inversion layer, while it showed multiple peaks out of the inversion layer.（2）Wind speed ranged between 2-8 m/s. The change of wind speed within 100 m near the ground was very obvious, while it is not obvious at 600-900 m. The speed value was approximately constant at900 -1 100 m.（3）The wind shear index at night was larger than that in the day, with the largest value of 20.88 at 23：00 and the lowest value of 0.97 at 14：00. The average valve of wind shear index is 9.61 and the average value of mixing layer thickness is 125.88 m.