Convective Interaction Between the Atmospheric Boundary Layer and the Surface

大气边界层与地表之间的对流相互作用

• 批准号: 9411467
• 负责人: Roland Stull
• 金额: $ 29.32万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-04-01 至 1998-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9411467&HistoricalAwards=false
• 关键词: Convective; Interaction; Between; Atmospheric; Boundary

Abstract ATM-941167 Stull The objective of this research is to explain atmospheric exchange processes near the surface. Because the boundary layer has finite thickness, processes at the bottom, in the interior, and the top of the boundary layer interact to modulate the next exchange. We will develop theories, gather new field data, and utilize existing data to study exchange processes at these three levels. To investigate processes at the bottom, we will examine the role of convective thermals in causing substantial surface transport during calm wind conditions. A relevant application is to the equatorial western Pacific, where heat and moisture fluxes contribute significantly to the global energy budget, but which are not well explained by traditional drag laws. Thermals also create a poorly-understood layer between the surface- layer and the mixed layer, which we will study with a variety of airborne platforms and wind profilers. Over heterogeneous topography, the boundary-layer top is not level. This causes complex scalings in the boundary layer, and plays a major role in convective cloud formation. We will investigate the levelness of the mixed-layer top with field data and with theory.

摘要本研究的目的是解释地表附近的大气交换过程。由于边界层的厚度有限，底层、内部和顶部的过程相互作用来调制下一个交换。我们将发展理论，收集新的现场数据，并利用现有数据来研究这三个层面的交换过程。为了研究底部的过程，我们将研究在无风条件下对流热气流在引起大量地面运输中的作用。一个相关的应用是赤道西太平洋，那里的热量和水分通量对全球能量收支贡献很大，但传统的阻力定律不能很好地解释这一点。热气流还在表层和混合层之间形成了一个鲜为人知的层，我们将用各种机载平台和风廓线仪来研究这个层。在非均质地形上，边界层顶部不是水平的。这在边界层中引起了复杂的缩放，并在对流云的形成中起着重要作用。我们将结合现场数据和理论研究混合层顶部的平整度。