Dust Transport in Convectively Stratified Atmospheric Boundary Layer

对流分层大气边界层中的粉尘输送

• 批准号: 1500224
• 负责人: William Anderson
• 金额: $ 22.15万
• 依托单位: University of Texas at Dallas
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1500224&HistoricalAwards=false
• 关键词: Dust; Transport; Convectively; Stratified; Atmospheric

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.

严重的风蚀和沙尘暴是美国南部、中部和西南部的一个令人担忧的问题。持续的干旱条件增加了风沙输送的可能性，风具有输送和沉积沙子和泥土等物质的能力。大气近地表边界层数值模拟方面的进展使人们能够更好地将涉及风沙输送的大气和地面过程联系起来，以便更好地了解尘埃事件将如何发生以及何时发生。这项研究的结果将是朝着提供更好的信息，以便就水资源和土地利用作出决定迈出的一步。这项研究还将包括各种教育和推广活动，将研究与学生和公众联系起来。这一奖项将为一项关于中性和对流分层大气边界层流动特征的研究提供资金，该研究重点是南高平原西德克萨斯狭长地带稀疏植被和半干旱景观上的流动。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地点。该提案的建模方面将以与美国农业部合作提供的田间数据为基础。具体任务将包括：确定使用孤立障碍物在气流中锚定低动量和高动量区域的潜力，确定太阳加热在改变湍流结构中的作用，以及将悬浮尘埃和惯性沉积物的输送纳入LES代码。