Mitigating urban heat islands to save cooling energy use, improve urban comfort and air quality, reduce heat-related mortality, and counter global warming

提案摘要 在夏季，凉爽的屋顶和凉爽的墙壁反射了大部分入射的阳光，减少了通过屋顶和墙壁的热传导。同样，战略性地放置树木，遮阳窗户和建筑物的墙壁减少了直接的热量获得。夏季热量增加的减少减少了建筑物的空调负荷，提高了舒适度，节省了高峰用电需求，并节省了资金。在冬季，凉爽的屋顶和遮荫的树木可能会增加建筑物的热负荷，然而，热能损失相当小（树木实际上可以通过保护建筑物免受冷风的影响来节省热能费用）。 随着城市的扩张，加拿大许多城市的夏季气温一直在稳步上升。此外，大多数新建筑物都装有空调;因此，当地的公用事业公司在夏季的高峰负荷很大。凉爽的城市表面与植被一起可以使城市降温几度，进一步减少冷却能源需求，改善环境空气质量，并降低夏季热应激相关的死亡率。 增加城市表面的太阳反射率，增加了短波辐射反射回太空。这种“负辐射强迫”的过程对抗全球变暖。据IPCC估计，每平方米地表的太阳反射率增加0.01，地球仪的降温效果相当于减少7公斤的二氧化碳排放量。将50%的城市地区的反射率增加0.10，使世界冷却相当于130 Gton的CO2（约为世界上所有汽车50年的排放量）。 该计划的目标是进行基础和应用研究，解决适合加拿大寒冷气候，建筑物和社区的能源效率和空气质量。我们将： 进行详细分析，以确定凉爽地表和植被对建筑物和社区能源使用以及城市空气质量的影响; 为几个加拿大城市建立详细的土地使用数据库（获得高分辨率正射影像并进行统计分析，以确定城市结构的特点）; 制定安装凉爽屋顶、凉爽路面和植被的指导方针; 开发适合加拿大气候的特定气候和区域的凉爽屋顶和凉爽铺路材料; 研究热岛效应和缓解技术对环境空气质量、市民舒适度以及夏季热应激死亡率和发病率的影响; （b）在城市温室气体增加与全球变暖之间建立特定区域的相关性; 协助地方、州和联邦政府制定区域能源法规、标准和实施指南; 举办讲习班和会议，向从业人员和决策者传播信息; 寻找和培训在建筑和社区设计、材料开发、气候和空气质量建模以及规范和标准开发方面有很强背景的HQP。

Summary of Proposal During the summer, cool roofs and cool walls reflect most of the incoming sunshine and reduce heat conduction through roofs and walls. Similarly, strategically placed trees, shading windows and walls of a building reduce the direct heat gain. The reduction in summer heat gains reduces the air-conditioning load of a building, improves comfort, saves peak demand electricity, and save money. During the winter, cool roofs and shade trees may add to the heating load of a building, however, the heating energy penalties are fairly small (trees can actually save heating energy bills by shielding a building from cold wind). Summertime temperatures in many Canadian cities have been steadily increasing with expansion of the city. Also, most new buildings are equipped with air-conditioners; as a result the local utility companies are experiencing significant summertime peak load. Cool urban surfaces together with vegetation can potentially cool down the city by a few degrees, further reducing cooling energy demand, improve ambient air-quality, and reduce summertime heat stress related mortality. Increasing the solar reflectance of urban surfaces, increases reflection of short-wave radiation back to space. This process of "negative radiative forcing" counters global warming. IPCC estimates that increasing the solar reflectance of a m2 of surface by 0.01 cools down the globe equivalent to reducing CO2 emissions by 7 kg. Increasing the reflectance of 50% urban areas by 0.10, cools down the world equivalent to 130 Gtonne of CO2 (~ 50 years of emissions from all cars in the world). The objective of this program is to perform basic and applied research addressing energy efficiency and air quality appropriate to Canadian cold climates, buildings and communities. We will: Perform detailed analysis to characterize effects of cool surfaces and vegetation on building and community energy use and urban air quality; Develop detailed land-use databases for several Canadian cities (obtain high-resolution orthophotos and perform statistical analysis to characterize urban fabrics); Develop guidelines for installing cool roofs, cool pavements, vegetation; Develop climate- and regional-specific cool roofing and cool paving materials appropriate for Canadian climate ; Conduct research on the impact of heat islands and mitigation technologies on ambient air quality, citizen comfort, and summertime heat-stress mortality and morbidity; Develop regional-specific correlation between increasing urban albedo and global warming; Assist local, states, and federal governments to develop regional energy codes, standards, implementation guidelines; Organize workshops and conference to disseminate information to practitioners and policy makers; and Seek and train HQP with strong background in buildings and community design, material development, climate and air quality modeling, and codes and standards development.