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塔克拉玛干沙漠腹地塔中地区的风动力环境   总被引:1,自引:0,他引:1  
输沙势是衡量一个地区风沙活动强弱的重要参数。为了更好地了解塔克拉玛干沙漠腹地塔中地区的沙粒运移状况,为沙尘暴预防与治理提供科学依据,通过地表土壤湿度修订出每个月的临界起沙风速以替代以往的一个经验值,进而以塔中气象站所提供的2006—2012年风速和风向数据为基础,研究了塔中地区的输沙势分布特征。结果表明:(1)起沙风风向主要分布在ENE,NE及E这3个方向上。(2)输沙势主要集中在春夏季。春季年平均合成输沙势分别为71.3VU,合成方向为31°;夏季年平均合成输沙势为59.7VU,合成方向为70.7°;冬季最小,合成输沙势仅为1VU。(3)春、夏、秋、冬方向变率指数都相对较大,说明塔中地区的风况较为单一。(4)春、夏、秋、冬4个季节的输沙势主要集中在ENE,NE及E这3个方向上。  相似文献   
2.
To improve the level of meteorological service for the Oilfield region in the Taklimakan Desert,the Urumqi Institute of Desert Meteorology of the China Meteorological Administration(CMA) conducted a detection experiment by means of wind profiling radar(WPR) in Tazhong Oilfield region of Xinjiang,China in July 2010.By using the wind profiler data obtained during the rainfall process on 27 July,this paper analyzed the wind field features and some related scientific issues of this weather event.The results indicated that:(1) wind profiler data had high temporal resolution and vertical spatial resolution,and could be used to analyze detailed vertical structures of rainfall processes and the characteristics of meso-scale systems.Before and after the rain event on 27 July,the wind field showed multi-layer vertical structures,having an obvious meso-scale wind shear line and three airflows from different directions,speeding up the motion of updraft convergence in the lower atmosphere.Besides,the wind directions before and after the rainfall changed inversely with increasing height.Before the rain,the winds blew clockwise,but after the onset of the rain,the wind directions became counterclockwise mainly;(2) the temperature advection derived from wind profiler data can reproduce the characteristics of low-level thermodynamic evolution in the process of rainfall,which is capable to reflect the variation trend of hydrostatic stability in the atmosphere.In the early stage of the precipitation on 27 July,the lower atmosphere was mainly affected by warm advection which had accumulated unstable energy for the rainfall event and was beneficial for the occurrence of updraft motion and precipitation;(3) the "large-value zone" of the radar reflectivity factor Z was virtually consistent with the onset and end of the rainfall,the height for the formation of rain cloud particles,and precipitation intensity.The reflectivity factor Z during this event varied approximately in the range of 18-38 dBZ and the rain droplets formed mainly at the layer of 3,800-4,500 m.  相似文献   
3.
南疆沙漠腹地地温变化特征   总被引:1,自引:0,他引:1  
利用塔中气象站三年的气象数据,分析了塔中地温的变化特征。结果显示:塔中0~40cm地温年变化规律显著,温度自1月开始迅速上升,在7月达到最高值,达30℃以上,其后又持续下降,冬季最低;80cm以下地温变化平缓,最高、最低温度出现月份逐渐后延,年振幅渐小;在典型晴天、阴天、沙尘天气时,表层地温都是日出前后最低,日出后迅速上升,至午后16时左右达最大值,其后迅速下降,于日落时降至一低值,并在夜间继续缓慢下降;四季0~80cm各层地温夏季﹥秋季﹥春季﹥冬季;天气对地温的影响主要体现在地表温度和浅层地温,至40cm及以下各层几乎无影响,日变化与典型晴天规律相同;阴天和浮尘对地温的影响较小,扬沙和沙尘暴天气对地温影响较大,其影响随深度增加而渐小;各层地温的平均日变化曲线近于正弦曲线,随深度增加地温特征线趋于平缓,极值出现时间逐渐后延。塔中地温的年际、日内变化的逐层性,与沙漠表面风成沙的物理属性有关。  相似文献   
4.
研究极端干旱区植物叶片生长特征对筛选防风固沙植物有重要意义。在塔克拉玛干沙漠腹地塔中植物园柽柳专类园区,选择8种不同柽柳,研究了生长季内叶片生长规律。结果显示:1)柽柳属不同种的单叶表面积增长模型较为类似,总体差异不大,但其增长的规律性极强,以y=ax2+bx-c二项式增长模型为主;2)方差分析发现,不同柽柳种间单叶面积差异极显著(F>F0.01);单叶鲜重和干重的差异亦明显;3)柽柳单叶表面积与其干重存在正相关关系,以y=axb的乘幂关系为主。说明塔中沙漠植物园不同柽柳叶面积增长特征有所不同,防护林和固沙树种选择过程中可优先考虑叶面积增长迅速,生物量积累快的柽柳-长穗柽柳和刚毛柽柳。  相似文献   
5.
A two-year field observation of saltation activity was carried out at Tazhong area,the hinterland area of the Taklimakan Desert with highly frequent dust storms.From 1 September 2008 to 31 August 2010,a piezoelectric saltation sensor(Sensit) was used to continuously collect the data on saltation activity at a level sand surface.Analysis on the data suggests that saltation activity can occur at any time of the year when conditions are favorable;however,the necessary conditions are rarely satisfied in most time.In the daytime of spring or summer,saltation activity can persist even over a continuous one-hour-or-so period.It is found that,from 1 September 2008 to 31 August 2010,saltation activity accounts for more than 3% of the total yearly time,and it tends to peak in spring and summer months with strong winds.During winter months when winds are weak,however,it is often at a minimum.It seems that precipitation does not appear to be significant in reducing saltation activity in arid regions like Tazhong.  相似文献   
6.
塔中奥陶系油气藏为礁滩型和层间岩溶储集体控制的碳酸盐岩缝洞型准层状凝析气藏,整体富气局部含油,储层非均质性强,相态特征复杂,气油比变化大。通过对塔中I号气田气油比变化特征,划分出基本稳定型、上升型、波动型和先升后降型4种气油比变化类型。分析了不同变化特征的主控因素,储集空间类型、驱动方式、相态变化及钻井轨迹是影响气油比变化的重要原因。根据这些影响因素,结合生产需要,提出了根据气油比变化在该气田的应用方法,如出水预警机制、钻井轨迹优化、提高采收率对策等。  相似文献   
7.
利用2014年7月至8月塔中地区沙尘与扬沙天气下风沙流运动的实测数据,对0~85 mm高度内风沙流运动进行了研究。结果表明:(1)0~85 mm高度层,输沙率(Q)随风速(v)增大呈幂函数规律增加,R2≥0.975 7,且输沙率主要集中在0~35 mm高度内。(2)总输沙率和撞击颗粒数的最佳拟合函数为线性函数,R2≥0.878 2,相关性较好;塔中地区1 min最小临界起沙风速为4.0 m·s-1。(3)跃移运动集中在10:00—20:00,总输沙率最大值出现在12:00—16:00,17:00以后输沙率明显下降。  相似文献   
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