PLEA Network

8 February 2016, The Conversation, In a heatwave, the leafy suburbs are even more advantaged. Summer brings out the heliophobe in many of us. It’s manageable if you live in a house that stays cool when shut up tight. It helps if you’re physically capable of crossing to the shadier side of a hot street. It’s even better if you can work from home or use public transport stops that enjoy the cover of buildings or trees. We have reason to think a lot about shade these days, especially as the heatwaves roll in. At such times, shade is our friend. On top of the existing urban heat island effect, the incidence of extreme heat events is rising. These events are also lasting longer and getting hotter. Coverage for all is a wonderful ideal, and the federal government has announced plans to set “urban canopy” targets. But, in the meantime, some communities and areas need trees more urgently than others. Shade is not only a matter of public health; it is a social equity issue. In a warming city like Melbourne, some of the most socially vulnerable people are in areas that are most exposed to extreme heat. Our pilot research in Melbourne suggests that integrated social and ecological data sets should be used to develop programs that reduce socioecological vulnerability. Shade can be a life-saver More than twice as many people perished in Melbourne during the 2009 heatwave leading up to Black Saturday than died in the devastating fires on that day. Extreme heat is a slow-motion disaster. The tendency to respond to heat as an emergency rather than planning for an ongoing chronic stress can have deadly consequences, as Annie Bolitho and Fiona Miller argue in a forthcoming paper. Extreme heat events are increasing in duration and intensity, and some parts of cities are more vulnerable than others. AAP/Bureau of MeteorologySocial and geographic isolation, age, disability and existing health conditions all play a role in vulnerability to heat. Vulnerability to urban heat also has a geography: vulnerability is compounded by where people live and whether trees live there with them. Urban authorities are using vegetation to help fight extreme heat in susceptible areas. In large sprawling cities like Melbourne, local councils are working to increase canopy cover in their jurisdictions. Urban forests can mitigate the urban heat island effect and significantly lower surface and ambient air temperatures. Read More here