摘要
利用2013年春季在巴丹吉林沙漠北缘拐子湖地区的沙尘暴加强观测资料,对比分析该地区典型流动沙面晴天、扬沙和沙尘暴三种天气背景下各气象要素的变化特征及差异,以便进一步了解沙尘天气过程中近地层风沙活动特征。结果表明:随风速增加沙尘天气强度逐步提升且沙尘天气来临前风速、风向均表现出明显的调整现象,风向调整时风速减弱,此后爆发过程中风速、风向相对稳定。随沙尘天气强度增加气温逐渐减小,同时地面气压不断升高。悬浮的沙尘颗粒削弱了到达地面的太阳辐射,进而导致研究区各层地温有减小趋势,但减小程度相对较弱,使沙尘天气下各层地温仍保持良好的梯度变化和正弦型日变化趋势。春季该研究区起沙风速为6.5 m/s,输沙通量垂直分布状况在20 cm左右具有明显的分段现象。地表100 cm内总输沙量的50%和90%分别集中在地表20 cm和56 cm高度以内。观测期间整个5月地表0耀100cm高度内的输沙通量为195.13 kg/m。
Based on the data of sandstorms in spring 2013 from flux observation stations at Guaizi lake region in the northern margin of the Badain Jaran desert, which was built by the Institute of Desert Meteorology of China Meteorological Administration, we analyzed the characteristics of blown-sand activites and meteorological elements of the near surface layer under different weather conditions （clear day, rising dust day and sandstorm day）. The results showed that the higher wind speed brought about stronger dust process. The wind speed and direction showed significant adjustment process before the dust weather, but it was relatively stable when it outbreaked. The ground temperature decreased with dust weather intensity increased. The floating dust resulted in that each layer of soil temperature showed a decrease tendency, but the degree of reduction was relatively weak. Moreover, the each layer of soil temperature under dust weather maintained good gradient changes and showed a diurnal variation trend of sine function curve. At the height of 2 m above surface, the instant sand-laden wind velocity for naturally mixed sands was about 6.5 m/s at one-minute interval. In the sand drift structure, the vertical sand flux was all in an increase trend with the increase of height below 20 cm from the ground. The vertical sand flux at all the height was exponent function decreased with the increase of height above 20 cm. The 50% and 90% of the total sand flux occurred mainly in the air layer below 20 cm and 56 cm from the ground, respectively. The sand flux within 0~100 cm height was 195.13 kg/m during the observation period.
出处
《沙漠与绿洲气象》
2015年第4期67-74,共8页
Desert and Oasis Meteorology
基金
国家自然科学基金(41175017
41175140)
中国沙漠气象科学研究基金(SQJ2012015)
公益性行业专项(GYHY201306066)联合资助
关键词
巴丹吉林沙漠
沙尘天气
气象要素
起沙风速
风沙流结构
Badain Jaran desert
sand-dust weather
meteorological elements
sand-laden wind velocity
structure of wind-blown sand flow
