CAREER: Multi-Scalar Transport and Similarity in the Urban Boundary Layer

职业：城市边界层的多标量交通和相似性

• 批准号: 2143664
• 负责人: Qi Li
• 金额: $ 54.94万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2143664&HistoricalAwards=false
• 关键词: CAREER; Multi; Scalar; Transport; Similarity

More than half of the global population live in urban areas, which nontrivially modify the atmosphere through two broad pathways: urban form (i.e., changes in surface properties) and urban function (i.e., anthropogenic activities emitting heat and mass). These two pathways occur via turbulent exchanges of momentum, energy and mass in the atmospheric boundary layer and carry ‘distinct fingerprints’ of a city’s form and function. For increasingly fine-scale climate and numerical weather prediction (NWP) models, it is a persistent challenge to reflect these ‘distinct fingerprints’ of different cities across the world, yet in a manner that is generalizable and computationally tractable. Due to incomplete understanding of multi-scalar transport, whether different scalars of anthropogenic origins obey similarity relations in the urban surface layer remains unclear. This is also one of the key stumbling blocks to generalize urban land-atmosphere exchanges for multiple scalars. In particular, incorporating the effect of urban function on surface-atmosphere exchanges into climate and NWP models is almost completely missing. Therefore, the overarching goal is to improve basic understanding of multi-scalar transport and inform physically realistic, generalizable estimates of the surface-atmosphere exchanges, especially for less explored scalars. The project will lead to findings necessary for the next-generation urban climate modeling tools, which can be implemented to develop more precise (i.e., city or neighborhood-specific) mitigation and adaptation measures with changing climates. To achieve the overall project goal, the approach of this project is motivated by a critical comparison between flow and transport in the urban canopy versus vegetated one, which has been extensively studied. Such an approach will generate new insight into the transferability of theories and models between the two, informing development of urban-specific models for surface-atmosphere exchanges based on the existing ones for vegetation counterpart. To advance basic understanding of multi-scalar transport and departure from similarity, the mechanisms responsible for scalar dissimilarity will be separately investigated at the micro- and local scale of heterogeneities in urban form and function. Understanding of multi-scalar transport at both the micro- and local scales will be systematically studied by first deriving a ‘city profile generation’ module to generalize urban form and function (Aim 1). Then, hypotheses regarding multi-scalar transport and their similarity will be tested to advance basic understanding (Aim 2). The new understanding will help improve urban surface-atmosphere exchange modeling and interpretation of observations that rely on scalar similarity theory (Aim 3).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

全球一半以上的人口居住在城市地区，城市通过两大途径显着改变大气：城市形态（即地表特性的变化）和城市功能（即散发热量和质量的人类活动）。这两条路径是通过大气边界层中动量、能量和质量的湍流交换而发生的，并带有城市形式和功能的“独特指纹”。对于规模日益精细的气候和数值天气预报 (NWP) 模型来说，以可推广且易于计算处理的方式反映世界各地不同城市的这些“独特指纹”是一个持续的挑战。由于对多标量传输的认识不完全，人类起源的不同标量在城市表层是否遵循相似关系仍不清楚。这也是推广多标量城市陆地-大气交换的关键障碍之一。 特别是，将城市功能对地表大气交换的影响纳入气候和数值天气预报模型几乎完全缺失。因此，首要目标是提高对多标量传输的基本理解，并为表面大气交换提供物理上真实的、可概括的估计，特别是对于较少探索的标量。该项目将得出下一代城市气候建模工具所需的发现，这些工具可以用于制定更精确的（即针对城市或社区的）气候变化缓解和适应措施。为了实现项目的总体目标，该项目的方法是通过对城市树冠与植被树冠中的流动和运输进行严格比较来推动的，这一点已经得到了广泛的研究。这种方法将对两者之间的理论和模型的可移植性产生新的见解，为基于现有植被模型的城市特定模型的表面大气交换模型的开发提供信息。为了增进对多标量交通的基本理解并摆脱相似性，将在城市形态和功能异质性的微观和局部尺度上分别研究造成标量差异的机制。首先推导“城市概况生成”模块来概括城市形态和功能（目标 1），系统地研究微观和局部尺度上的多尺度交通的理解。然后，将测试有关多标量传输及其相似性的假设，以增进基本理解（目标 2）。新的理解将有助于改进依赖于标量相似理论（目标 3）的城市地表-大气交换建模和观测解释。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Using Machine Learning to Predict Urban Canopy Flows for Land Surface Modeling

• DOI: 10.1029/2022gl102313
• 发表时间: 2022-12
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Yanle Lu;Xueqing Zhou;Heng Xiao;Qi Li

Long-distance atmospheric transport of microplastic fibres influenced by their shapes

• DOI: 10.1038/s41561-023-01264-6
• 发表时间: 2023-09
• 期刊: Nature Geoscience
• 影响因子: 18.3
• 作者: Shuolin Xiao;Yuanfeng Cui;J. Brahney;Natalie M. Mahowald;Qi Li

Understanding the Influence of Urban Form on the Spatial Pattern of Precipitation

了解城市形态对降水空间格局的影响

• DOI: 10.1029/2023ef003846
• 发表时间: 2024
• 期刊: Earth's Future
• 作者: Lu, Yanle;Yu, Zhou;Albertson, John D.;Chen, Haonan;Hu, Leiqiu;Pendergrass, Angeline;Chen, Xiaodong;Li, Qi
• 通讯作者: Li, Qi

Effects of Urban Surface Roughness on Potential Sources of Microplastics in the Atmospheric Boundary Layer

• DOI: 10.1007/s10546-022-00763-0
• 发表时间: 2022-12
• 期刊: Boundary-Layer Meteorology
• 影响因子: 4.3
• 作者: Yuanfeng Cui;Shuolin Xiao;M. Giometto;Qi Li