Why half a million Australian properties could be all-but uninsurable

New research by risk management group AON and Monash University shows 370,000 homes and 120,000 commercial properties across Australia face a 1 per cent annual risk of flooding, equating to 25 per cent risk over the life of a standard mortgage.

“I think [the finding] would make people think twice about buying in those locations,” said AON climate risk advisory lead Dr Tom Mortlock. “I mean, you wouldn’t go on a plane if there was a one-in-four chance of it falling from the sky, right?”

ADF personnel were called in to help flood-affected communities on the mid-north coast in 2021.Credit: Wolter Peeters

He said most home insurance policies excluded so-called “actions of the sea”, and didn’t cover erosion or flooding from storm tides or wave activity.

“If you knew that your home contents insurance would not cover actions of the sea, you know the risk burden is then on you for basically rolling the dice at a one-in-four chance of getting impacted by coastal floods or erosion,” Mortlock said.

In the paper Mortlock wrote with Dr Felicity McCormack, a senior research fellow for Securing Antarctica’s Environmental Future at Monash University, the pair says atmospheric and ocean warming are accelerating glacier and ice sheet melting.

“I mean, you wouldn’t go on a plane if there was a one-in-four chance of it falling from the sky, right?”

Dr Tom Mortlake

“Glaciers and ice sheets combined are likely to overtake every other driver of sea level rise over the coming decades and become the majority contributors to the 0.44 metres (medium emissions scenarios) to 0.77 metres (high emissions scenarios) of likely sea level rise by 2100.”

In the Australian context, this means increased storm surges, which will increasingly damage coastal infrastructure and properties.

“While there’s a lot of uncertainty, we know that the more carbon dioxide we pump into the atmosphere, the faster we will melt the ice sheets, and the more rapid and the higher magnitude the sea level rise,” McCormack said.

The report comes after months of record-breaking temperatures that alarmed scientists, and as UN Secretary-General Antonio Guterres prepares to host the 53rd Pacific Islands Forum in Tonga on Tuesday. The summit will focus heavily on the impacts the climate crisis is having on the Pacific region.

Speaking in Samoa ahead of the summit, Guterres called on the world community – particularly G20 countries including Australia – to take stronger action to cut global emissions.

“The climate crisis is the gravest threat facing this country and this region – and, quite possibly, the world,” he told reporters at Samoa House.

“The Pacific contributes 0.02 per cent of global emissions. Yet, you are on the frontlines of the climate crisis, dealing with extreme weather events from raging tropical cyclones to record ocean heatwaves.”

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