Understanding urban thermal anisotropy

了解城市热各向异性

• 批准号: 194105-2011
• 负责人: Voogt, James
• 金额: $ 1.6万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=546051
• 关键词: Understanding; urban; thermal; anisotropy

Cities, home to over half the world's population, create important modifications to the surface and atmosphere. These changes result in distinct urban climates that affect local weather, the demand for energy, the livability of cities and the export of pollutants and greenhouse gases to larger scale climates. Surface temperatures are a key component of urban climate because they represent a solution to the surface energy budget - the inputs and outputs of heat at the surface. Thus, accurate measurement and modeling of urban surface temperatures is critical for understanding processes and applications of urban climate. Thermal remote sensing provides an attractive means of observing surface temperatures over the complex urban surface. Unfortunately such observations are characterized by strong "anisotropy", a directional variation in the observed signal that occurs due to the three dimensional (3-d) urban surface structure and associated 3-d surface temperature variations. Anisotropy infers important biases and a failure to capture the full 3-d pattern of urban surface temperature, thereby limiting the applicability of such data to the study of urban climates. This proposal is concerned with understanding urban thermal anisotropy, the development of techniques that can address the limitations imposed by anisotropy and the application of those techniques to urban climate issues. The results of this research will provide improved methods for measuring and modeling surface temperatures in urban areas and in their application to urban environmental problems.

城市是世界以上人口一半以上的所在地，为地表和气氛创造了重要的修改。这些变化导致不同的城市气候影响当地的天气，对能源的需求，城市的宜居性以及污染物和温室气体的出口到更大的气候。表面温度是城市气候的关键组成部分，因为它们代表了表面能预算的解决方案 - 表面热量的输入和输出。因此，对城市表面温度的准确测量和建模对于理解城市气候的过程和应用至关重要。热遥感提供了一种在复杂的城市表面上观察表面温度的吸引人方法。不幸的是，此类观察结果的特征是强烈的“各向异性”，这是由于三维（3-D）城市表面结构和相关的3-D表面温度变化而发生的观察到信号的方向变化。各向异性会渗透重要的偏见，并且无法捕获城市表面温度的完整3-D模式，从而限制了此类数据对城市气候研究的适用性。该提案涉及了解城市热各向异性，即可以解决各向异性限制的技术的发展以及这些技术在城市气候问题上的应用。这项研究的结果将提供改进的方法，用于测量和建模城市地区的表面温度以及将其应用于城市环境问题。