Rising sea levels represent threat to Australian property

A new website called Coastal Risk Australia has launched, which combines Google Maps data and projected median sea levels from Intergovernmental Panel on Climate Change (IPCC), to inform users of the risks to property from climate change. It predicts that by 2100, many Australian houses and famous landmarks could be underwater with every state and territory apart from the ACT potentially affected if sea levels rose by 5m. A beta version of another website, Climate Valuation Project, also launched last week, which aims to help people make property investment decisions, offering a flood probability service, estimating potential insurance premium increases from coastal inundation risks and calculating resultant percentage movements in property values.

For the first time, Australians can see on a map how rising sea levels will affect their house just by typing their address into a website. And they’ll soon be able to get an estimate of how much climate change will affect their property prices and insurance premiums, too.

Launched on Friday, the website Coastal Risk Australia takes Google Maps and combines it with detailed tide and elevation data, as well as future sea level rise projections, allowing users to see whether their house or suburb will be inundated.

Coinciding with that is the launch of a beta version of Climate Valuation, a website that gives users an estimate of how much climate change will impact their property value and insurance premiums over the life of their mortgage.

Coastal Risk Australia uses median sea level rises projected for 2100 by the Intergovernmental Panel on Climate Change under low, medium and high greenhouse gas emissions scenarios.

On the high emissions scenario – which is the path the world is currently on – the IPCC says sea levels will likely rise by a median of 0.74m by 2100. But a rise of almost 1m is within the “likely” range of levels that could be reached by 2100.

In every state and territory except the ACT, the website shows that houses and famous landmarks will be underwater by 2100. Beaches like Manly, Byron and Coogee in New South Wales would lose significant amounts of sand, as will Bell’s Beach in Victoria and Noosa in Queensland.

Many coastal suburbs and cities are shown to be subject to severe inundation, including Cairns, Ballina and Hindmarsh Island.

James Hansen, a former Nasa scientist who is considered the father of modern climate change awareness, recently produced research suggesting that sea levels could rise “several metres over a timescale of 50 to 150 years”.

The website also lets users see how any sea-level rise will affect an area. If sea levels rose 5m, then large parts of most coastal cities would be inundated, according to the website’s calculations.

A visualisation of Sydney’s eastern suburbs in 2100, under the five-metre sea level rise scenario. Photograph: Coastal Risk Australia

“We don’t want to create hysteria but we don’t want people burying their heads in the sand ether,” said Nathan Eaton, one of the creators of the website from the company NGIS Australia.

The tool was adapted from work NGIS did when it created a similar tool for the Pacific Island nations of Tonga, Samoa, Vanuatu and Papua New Guinea, in collaboration with the Australian Department of Environment and the Collaborative Research Centre for Spatial Information.

Climate Valuation, also launched on Friday, will, for a fee, tell users the probability of a property being flooded by rising sea levels; the projected increases in insurance premium from coastal inundation risk; and the projected percentage reduction in value of the property at the end of a mortgage.

It is being launched for use by researchers initially and will soon be available as part of a Kickstarter campaign, which the developers say will raise money to include more climate change-associated risks like bushfires and river flooding. People who pledge to contribute will get early access to it.

The developers say the site uses risk engines that are already used to assess billions of dollars of critical infrastructure in Australia and the new site will give the general public access to that data for the first time.

“We’re hoping this helps people make informed decisions about their safety and on what is often the most significant investment they will ever make – their home,” said Karl Mallon, head of the Climate Valuation Project.