http://www.reuters.com/article/latestCrisis/idUSSYD485609

Australia needs to adopt a national policy to combat rising sea levels, which may see people forced to abandon coastal homes and banned from building beachside homes, said a parliamentary climate change committee.

The committee's report said that A$150 billion ($137 billion) worth of property was at risk from rising sea levels and more frequent storms.

Australia is an island continent with 80 percent of its 21 million people living on the coast. Authorities are split on adopting a policy of retreat or defence against rising seas.

The country's current coastal management policy is fragmented and authorities need to adopt a national policy to coordinate new coastal building codes, and relocation and evacuation plans, said "Managing Our Coastal Zone in a Changing Climate" report.

Australia must examine the legal liability and insurance cover associated with property loss and damage due to climate change, improved early warning systems for extreme seas, and work to prevent the spread of tropical diseases such as dengue fever.

"The key message that emerged from the inquiry is the need for national leadership in managing Australia's coastal zone in the context of climate change," Jennie George, a government MP and committee chair, said in launching the report on Tuesday.

"This is an issue of national significance."

The report said thousands of kilometres of coast around Australia was at risk from rising sea levels and extreme weather events caused by climate change.

An estimated 711,000 homes were within 3 km (2 miles) of the coast and less than 6 metres (yards) above sea level.

Tropical Queensland state was the most at risk, with almost 250,000 buildings vulnerable. Next was the most populous state New South Wales (NSW) with more than 200,000. Coastal flooding and erosion already costs NSW around A$200 million a year.

The report called for a national policy which could see government authorities prohibit occupation of land or future building development on property due to sea hazards.

It called for building codes, including cyclone building codes, be revised to increase resilience to climate change.

The Intergovernmental Panel on Climate Change estimates that a global rise in sea level of some 80 cm (31.5 inches) is possible by 2100.

But the report warned a mean sea level rise was not the major threat to coastal property, but more frequent storms and sea surges on top of higher sea levels posed the greatest risk.

"The gradual rise of sea level will continue to be almost imperceptible," it said. "Elevated sea levels will lead to an increase in the potential impact of extreme sea level events caused by storm surges and heavy rainfall." ($1=1.092 Australian Dollar)