Dust Transport in Convectively Stratified Atmospheric Boundary Layer

严重的风蚀和沙尘暴是美国中南部和西南部地区的一个问题。长期的干旱条件增加了风成运输的可能性，风有能力运输和沉积沙土等物质。大气近地表边界层数值模拟的进展，使我们能够更好地把涉及风成输送的大气过程和地面过程联系起来，以便更好地了解沙尘事件发生的方式和时间。这项研究的结果将是朝着提供更好的资料以作出有关水资源和土地利用的决定迈出的一步。这项研究还将包括各种教育和推广活动，以将研究与学生和公众联系起来。该奖项将为中性和对流分层大气边界层流动特征的研究提供资金，特别关注德克萨斯州西部南部高平原狭长地带植被稀疏、半干旱地区的流动。该地区以严重的风蚀和沙尘暴而闻名，最小的地形起伏使该地区成为使用大涡模拟（LES）模型进行基础研究的理想场所。该提案的建模方面将以与美国农业部合作使用的实地数据为基础。具体的任务将包括：确定利用孤立障碍在流动中锚定低动量和高动量区域的潜力，确定太阳能加热在改变湍流结构中的作用，并将悬浮尘埃和惯性沉积物的运输纳入LES代码。

Severe wind erosion and dust storms are a concern in the south central and southwestern parts of the United States. Prolonged drought conditions enhance the potential for Aeolian transport, where wind has the ability to transport and deposit materials such as sand and dirt. Advances in numerical modeling of the near-surface boundary layer of the atmosphere have made it possible to better connect the atmospheric and surface processes involved in Aeolian transport, in order to better understand how and when dust events will occur. The results of this study will be a step towards providing better information on which to make decisions regarding water resources and land use. The study will also include a variety of educational and outreach activities to connect the research to students and the public.This award will provide funding for a study on the characteristics of neutrally and convectively stratified atmospheric boundary layer flows with a particular focus on flow over sparsely vegetated, semi-arid landscapes on the west Texas panhandle region of the Southern High Plains. The location of interest is known for severe wind erosion and dust storms, and the minimal topographic relief makes the region ideal for fundamental research studies with large-eddy simulation (LES) models. Modeling aspects of the proposal will be grounded by the use of field data courtesy of a collaboration with the US Department of Agriculture. Specific tasks will include: determining the potential to anchor low- and high-momentum regions in the flow using isolated obstacles, determining the role of solar heating in modifying the turbulence structure, and incorporating transport of suspended dust and inertial sediment into the LES code.