More than 700,000 coastal homes are at risk from wild storms and rising sea levels caused by climate change, the federal government says.
It will map most major Australian cities to work out which homes are most at risk.
Sydney, Melbourne, Adelaide, Perth, Brisbane and the Gold Coast would be mapped in a $2 million digital model, Climate Change Minister Penny Wong said as she announced the funding in Fremantle.
"Already, more than 700,000 residences across Australia are estimated to be at threat from the effects of climate change, including storm surges and extreme weather events," she said.
"Acting on climate change is all about doing the responsible thing for the economy and for the future."
The new digital elevation model will build on the government's knowledge of which areas are most exposed to inundation. There is already a model in place, although it has a lower digital resolution.
The new version will be put together by scientists and commercial mapping companies.
Groups involved include the CSIRO, Geosciences Australia, the Cooperative Research Centre for Spatial Information, and the Australia and New Zealand Land Information Council.
Ms Wong also announced $310,000 for a web-based tool to allow planners and policy-makers to incorporate rising sea levels into planning codes.
There's also $479,000 to develop a tool to forecast how climate change affects wave patterns.
"Taking action on climate change will be very hard, but we have already had too many years of neglect and delay," Ms Wong said.
"Further delay is economically irresponsible."