The recent spate of vertical, high-density development in cities such as Melbourne could be making them far more susceptible to the potential hazards created by global climate change.

According to Professor Brendan Gleeson, Director of the Melbourne Sustainable Society Institute, the impacts of global warming are already being felt in some of Australia’s major cities, serving as a harbinger of change in other parts of the country.

“Looking at the bigger picture in terms of the cities, Perth has already arguably been quite heavily impacted by climate change, registering what appears to be a permanent decline in its annual rainfall and loss in its catchment capacity,” said Gleeson. “For all of the major cities, one of the biggest issues is going to be heat stress and the increase in the number of extreme heat days in any given summer.”

Gleeson said the rising density of Australia’s urban centres as a result of ongoing population gains will have a highly adverse effect upon their ability to withstand this rise in heat stress – particularly given the poor quality of more recent developments.

“Where we are particularly vulnerable is in the highest density parts of our cities,” he said. “Already we can see patterns like ambulance call outs in heat stress events, with the inner city and higher density areas of place like Melbourne being amongst the worst affected.”

According to Gleeson, this susceptibility to heat stress is further worsened by the comparatively poor quality of Australia’s late wave of dense high-rise construction.

This is particularly the case in Melbourne, which according to according to research by Leanne Hodyll is on track to become one of the world’s densest urban centres.

“There’s enough on the record to show that there’s been some really inferior construction going on – there’s a already a national discussion going on about the dangers of the cheap and highly flammable cladding that’s been used for example in recent towers,” said Gleeson.

“We’ve had some really inferior forms of development over the last decade or so, producing risky and dangerous environments for the people the residing in them. From what I understand the fire brigade won’t even attend some of them – they are so flammable, so dangerous, and so poorly designed.”

Gleeson noted that in Melbourne the latest spate of high quality, low density development is not due to decisions by the municipal authorities but instead to those of the state government, which exercises planning rights over its capital city.

“Melbourne City Council has had a very difficult situation in that the approval authority for most of that high density development has been the state government – it’s been taken out of the council’s hands,” he said. “That’s quite unusual – it not the case for Sydney or many other CBD councils in Australia.”

While the current trajectory of development in downtown Melbourne may leave it struggling to deal with the ill effects of climate change in future, Gleeson nonetheless lauds the efforts of the municipal government to mitigate the damage caused by poor planning policy.

“I think given the circumstances, Melbourne City Council has been an exemplar in attempting to respond and deal with the challenges of climate change,” he said. “In some ways they’ve been left to clean up the mess, and I think in that context acting really well.”

“They’ve also been doing some really excellent and internationally recognised work in the adaptation space, appointing a resilience officer, setting some of the most ambitious decarbonisation targets for any city in the world, rolling out the urban tree coverage strategy, emphasising those areas of urban development that they can control, and recognising just how powerful that intervention can be in making cities and urban fabrics safer in the context of a warmer and wilder climate.

“But they’ve effectively had the control levers for more problematic forms of development removed from their hands quite a long time ago.”

While Melbourne City Council may have found itself compelled by circumstance to pursue these praiseworthy measures, Gleeson remains hopeful that government at higher levels has become heedful of the potential perils of urban densification.

“There needs to be a major think about what happens from now – about further development and prospects for further influx of population – for example in the Fisherman’s Bend redevelopment area, where the ambition was for a major influx of population,” he said. “I think we need to have pause to think about a) whether that’s appropriate given the circumstances we face and b) the form of redevelopment that should be there.

“The state to its credit has now finally introduced a process to review and rethink what’s happening in Fisherman’s Bend with those issues in mind.”