Impacts of green roofs on storm water management and urban climate

几个世纪以来，绿色屋顶一直被用来隔热建筑物和美丽的城市环境。欧洲国家，尤其是德国，已经在现代建筑中采用了绿色屋顶，这有助于提高人们对其许多潜在好处的认识。绿色屋顶已被证明：通过减轻城市下水道系统的负担，有效地减少和过滤雨水；提供隔热和降低屋顶表面温度，从而减少建筑能量负荷和相关的碳排放；通过减少导致屋顶损坏的温度波动，延长屋顶的使用寿命。鉴于绿色建筑可以缓解暴雨径流的负面影响，并减少供暖和制冷需求，在加拿大使用绿色屋顶可能会被证明是非常有益的，因为我们的气候极端。然而，北美城市环境中绿色屋顶的实施仍然没有得到充分利用，部分原因是缺乏适合气候的绿色屋顶设计指南。在这个项目中，将在加拿大的三个城市研究绿色屋顶的使用，形成全国经历的具有代表性的天气条件样本。这包括寒冷的冬季和干燥的夏季(卡尔加里，阿肯色州)，中间的冬季和潮湿的夏季(伦敦，安大略省)，温和的冬季和高降水事件(哈利法克斯，南卡罗来纳州)。在每个地点，将使用不同的植被类型、屋顶坡度和生长介质深度，并将测量重要参数，以评估这些变量对绿化屋顶性能的影响。该项目将支持六名暑期学生、六名研究生和一名博士后建造绿色屋顶，收集必要的数据，描述加拿大环境中的绿色屋顶性能，并开发一个数值模型来优化绿色屋顶设计。这项研究将提供有价值的工具，以采取更环保的方法来设计绿色屋顶，并量化加拿大使用绿色屋顶的好处。因此，这项研究将导致加拿大更多地使用绿色屋顶，从而产生许多经济、环境和健康效益，并改善加拿大的城市环境。

Green roofs have been used for centuries to insulate buildings and beautifyurban environments. European countries, especiallyGermany, have adopted green roofs for use in modern buildings, helping raise awareness of their manypotential benefits. Green roofs have been shown to: effectivelyreduce and filter stormwater therebydecreasing the burden on urban sewer systems; providing insulation and lowering roof surface temperature leading to a decrease in building energyload and associated carbon emissions; and extending the life of a roof bydecreasing the temperature fluctuations which cause roof damage. Given that green buildings can mitigate against the negative impacts of storm water runoff and reduce the heating and cooling demands, use of green roofs in Canada might prove extremelybeneficial due to our climate extremes. However, the implementation of green roofs in North American urban environments remains underused, in part due to a lack of climate appropriate green roof design guidelines. Inthis project, the use of green roofs will be studied in three cities in Canada, forming a representative sampleof weather conditions experienced across the country. This includes cold winters and drysummers (Calgary, AB), intermediate winters and humid summers (London, ON), and mild winters and high precipitation events (Halifax, NS). At each site, different vegetation types, roof slopes, and growth medium depth will be used and important parameters will be measured to assess the impact of these variables on green roof performance. The project will support six summer students, six graduate students, and one postdoctoral fellow to construct the green roofs, collect the necessarydata, characterize green roof performance in Canadian environments, and develop a numerical model to optimize green roof design. This studywill provide valuable tools to take a morerigorous approach to green roof design and quantifythe benefits of green roof use in Canada. As a result, this studywill lead to an increased use of green roofs in Canada, resulting in manyeconomic, environmental, and health benefits and the improvement of Canadian urban environments.