Evaluating the Urban Heat Island Mitigation Potential in the foothills of Uttarakhand, India through Green Roofing Systems

Globalization has accelerated the rate of urbanisation at the cost of environmental degradation and making cities vulnerable to the impacts of climate change. Increased urbanization has contributed to the Urban Heat Island Effect and it is important for the sustainable urban development to mitigate UHI, especially among the nations of growing economies i.e. India. Additionally the commercial, industrial, transportation and building sectors emit a large quantity of global house gases in the environment adding to UHI in the urban areas. Of all these sectors, the building is one of the largest contributors mainly due to carbon emissions, reduced natural landscapes and long wave solar radiation reflecting back from hard roof surfaces. Therefore mitigating UHI caused by the building sector is imperative with green roofs having been identified as one of the best practices.

In northern India the Himalayan belt is experiencing tremendous urban growth for various reasons from religious destinations to natural forest cover for tourism . Both land use and land cover of the Himalayan foothills are changing rapidly from being green (vegetation) to grey (concrete roofs) and thus increasing the Urban heat island intensity. This meta study examines the Urban Heat Island phenomenon in Dehradun based on LANDSAT data of the last decade. The study identifies hot spots and evaluates the potential of installing a green roofing system on existing roofs.. The results of this study may be recognised as best practices to be carried forward for other similar regions in the Himalayas.