I was honoured to deliver a keynote at the European Forum on Urban Forests. More than 80 international delegates gathered for this week-long meeting, hosted in Europe’s Green Capital, Ljubljana, Slovenia, to discuss the future of urban forests, particularly in the face of climate change.
Increasing heat waves was a major theme of the forum and with good reason. Heat causes more annual deaths than any other weather related event. Global data consistently shows an association between increased daily temperatures and increased deaths, illness, and hospitalizations[1]. In most cities studied, the risk of death increases by between 1% and 3% for every 1°C increase in high temperature. This 1°C impact is important to remember when considering that urban forests provide cooling between 1- 7 °C, with the greatest differences taking effect when a city is at its hottest.
With the understanding that trees can act as ‘first responders’ in a heat wave, and even reduce the pressure on hospitals and health services, our discussions centred on the need to reframe urban forests in city planning from aesthetic and recreational amenities to vital urban life support. In response to this need, the Food and Agriculture Organization of the United Nations launched the Trees for the Cities Dgroup. This workspace allows us to promote global and regional alliances for urban governance and raise awareness of the health benefits of urban forests. We’ve recently been focused on the ground breaking report Planting Healthy Air that quantifies health benefits of trees for 245 cities globally and shows how an investment of $4 USD in tree planting per person could improve the health of millions of people.
My talk emphasized how the champions of urban forests are really frontline health workers, so I was thrilled when, the following day, urban foresters donned white medical coats – to claim the place of urban forests in our health care system. Image: Boštjan Hren
But where should this $4 per person be invested? A conversation about urban heat and climate change is not complete without considering who is most at risk, most disadvantaged and most reliant on public infrastructure. Our own work in Canada, examining decades of research on the health benefits of urban forests, shows that tree cover is not evenly shared. Sparse landscapes often reveal the pockets of urban poverty. Inner-city residents, living on low-incomes, may face increased health risks from heat exposure in addition to other social and health challenges related to poverty. The association between green space and reduced mortality is found to be strongest in the most socioeconomically deprived urban areas. Opportunities for health gains are greatest when tree planting is focused in disadvantaged and underserved neighbourhoods, in conjunction with robust social housing policies to ensure greener neighbourhoods remain affordable neighbourhoods.
There is no doubt that there is a sense of angst over the future of cities. Futuristic films habitually depict dystopian tree-less dust bowls in our future. While these images may reflect a collective concern, they also reflect a lack of vision. There is great potential to move away from grey/brown cities to prolific green cities but it requires collective vision, and political will. It also requires a cultural shift to value urban forests beyond their aesthetic appeal. Finally, on a practical level, it requires the close collaboration of public health and urban planning – to find a shared language for advocating to decision makers.
It was a great privilege to join the 2016 delegation in Ljubljana, and I look forward to continued hard work with others in this arena. Thank you to Dr. Urša Vilhar and Dr. Andrej Verlič for your warm welcome in such a beautiful city. And thank you to Aryne Sheppard and Faisal Moola at the David Suzuki Foundation for supporting this work.
[1] Vutcovici, Goldberg & Valois, 2013.