Low carbon districts: Mitigating the urban heat island with green roof infrastructure

- As cities expand preserving biodiversity becomes essential.
- A re-densified, compact inner-city location is always more favourable than a suburb.
- Green roofs contribute to the mitigation of the urban heat island effect.
- Other ways include urban farming, roof-top gardening and green walls.
- The natural cooling effect of greenery uses the process of evapotranspiration.

New urban design concepts should guide the inclusion and re-introduction of greenery and biodiversity in the urban built environment. Preserving biodiversity in the face of urbanization, habitat fragmentation, environmental degradation and climate change is probably one of the greatest challenges of our time. The integration of trees, shrubs and flora into green spaces and gardens in the city is particularly important in helping to keep the urban built environment cool, because buildings and pavements increase heat absorption and reflection (what is called the urban heat island effect). Tomorrow's urban precincts will have to offer new forms of green spaces, both for recreation and also to mitigate the warmer urban climate. In addition, future urban precincts will have to generate at least half of their power themselves. Integrated urban development with a focus on energy, water, greenery and the urban microclimate will have to assume a lead role and urban designers will engage with policy makers in order to drastically reduce our cities' consumption of energy and resources. This paper introduces the holistic concept of green urbanism as a framework for environmentally conscious urban development. Then one of Australia's largest urban renewal projects: the Barangaroo waterfront development at East Darling Harbour in Sydney. At Barangaroo, all roofscapes will be green roofs, contributing to the mitigation of the urban heat island effect and collecting rainwater; this inner-city precinct is setting new standards for Australian urban renewal, including solutions for environmental, energy and roofscape issues.