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生活在城市地区，城市通过两条主要途径对大气层进行了重要的改变：城市形态（即，表面特性的变化）和城市功能（即，排放热量和质量的人类活动）。这两条路径通过大气边界层中动量、能量和质量的湍流交换发生，并携带着城市形式和功能的“独特指纹”。对于越来越精细的气候和数值天气预报（NWP）模型，这是一个持续的挑战，以反映这些不同的城市在世界各地的“独特的指纹”，但在某种程度上，是概括和计算处理。由于对多标量输运的不完全理解，在城市近地层中不同的人为源标量是否服从相似关系仍不清楚。这也是将城市陆气交换推广为多标量的关键障碍之一。 特别是，将城市功能对地表-大气交换的影响纳入气候和NWP模式几乎完全缺失。因此，总体目标是提高对多标量输运的基本理解，并为地表-大气交换的物理现实的、可推广的估计提供信息，特别是对于探索较少的标量。该项目将导致下一代城市气候建模工具所需的发现，这些工具可以用于开发更精确的（即，城市或社区特定的）缓解和适应气候变化的措施。为了实现项目的总体目标，该项目的方法是由一个关键的比较，在城市冠层与植被，这已被广泛研究的流量和运输的动机。这种方法将产生新的见解，两者之间的理论和模型的可移植性，为城市特定的地表-大气交换模型的发展提供信息的基础上，现有的植被对应。为了推进多标量运输和偏离相似性的基本理解，负责标量相异性的机制将分别在微观和局部尺度的城市形式和功能的异质性进行研究。在微观和局部尺度的多标量运输的理解将系统地研究，首先推导出一个“城市轮廓生成”模块，概括城市的形式和功能（目标1）。然后，将测试关于多标量传输及其相似性的假设，以促进基本理解（目标2）。新的理解将有助于改善城市地表-大气交换建模和解释观测依赖标量相似理论（目标3）。该奖项反映了NSF的法定使命，并已被认为是值得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的支持。

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

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

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