ABC Net 15 Dec 10;
Rising sea levels are likely to cause serious and regular flooding in Australian coastal cities by the end of the century, according to maps released by the Federal Government today.
The maps for low-lying areas in Melbourne, Sydney, Perth, Newcastle, the New South Wales' central coast and south-east Queensland show significant levels of inundation by the year 2100.
The maps show three different scenarios, with the lowest rise of 50 centimetres representing a situation which is likely to be unavoidable.
The medium level map shows a rise of 80cm and the highest level of 1.1 metres shows the flooding risk identified in the most recent climate change research.
The Government says the flooding shown in the maps is likely to occur at least once a year.
Climate Change Minister Greg Combet says the maps will help communities prepare for the effects of climate change.
"The Government recognises that coastal areas of Australia are a priority for adaptation action, with many communities vulnerable to impacts such as erosion and sea inundation," Mr Combet said.
"Developed in partnership with the Co-operative Research Centre for Spatial Information, these maps are an important product for the community to understand potential risks to infrastructure and properties and to prepare for the climate change impacts of sea level rises."
Mr Combet says the maps show rising sea levels may affect existing infrastructure.
"We need to face the challenge of starting to prepare for impacts to existing developments, where past decision-making did not address climate change impacts and where areas may be vulnerable to inundation as the sea level rises," he said.
"Early engagement with communities in these areas will be critical to the development of workable adaptation solutions for local areas, so they are able to avoid risk.
"Where this is not possible, this engagement will help ensure they are as prepared as possible to cope with climate change impacts as they arise."
Rising sea levels will swamp parts of Sydney
Tom Arup Sydney Morning Herald 16 Dec 10;
A number of Sydney suburbs will be inundated regularly because of climate change-driven sea-level rises, threatening homes and community infrastructure worth billion of dollars by the end of the century, new projections show.
In the first detailed attempt to study the impacts of sea-level rises on low-lying coastal areas and help local government planning, the government has released high-resolution maps that show the areas in Sydney and the central coast most under threat from sea-level rises.
Sydney suburbs facing significant danger of inundation, even with limited rises, include Caringbah, Kurnell, Cromer and Manly Vale. Significant parts of Newcastle and the central coast are also potentially in harm's way.
And the problems associated with rising sea levels are not limited to coastal areas. Flooding could occur along the Parramatta River, threatening homes and infrastructure around Homebush Bay, Newington and Silverwater.
Along the Cooks River, Arncliffe and Marrickville could suffer, with the threat of significant inundation at Sydney Airport, too The maps show projected inundation for sea-level rises of 0.5 metres, which is likely to be unavoidable, 0.8 metres and 1.1 metres by 2100.
The projections combine rising sea levels and king tidal events, which can occur many times a year. The maps do not factor in protective infrastructure such as sea walls or show local effects such as beach erosion.
Tim Flannery, who sits on the federal government's Coast and Climate Change Council, said he had been struck by the significant effects on inland suburbs from river flooding in all major Australian cities.
Professor Flannery said he hoped the maps would drive a national strategy to co-ordinate Australia's approach to sea-level rises, including universal planning laws.
Bruce Thom, the chairman of the Australian Coastal Society, said the next stage of projections would deal with localised studies, including the potential damage from flooding events on land and storm surges from the sea, which he said would show the real risks of rising sea levels.
The Climate Change Minister Greg Combet, who launched the maps in Newcastle yesterday, said in a statement the government recognised ''that coastal areas of Australia are a priority for adaptation action, with many communities vulnerable to impacts such as erosion and sea inundation''.
Last year the government released data revealing that an estimated 247,600 buildings valued at $63 billion could be damaged or lost due to sea-level rises.
In the same data, up to 62,400 homes in NSW - worth $18.7 billion - were estimated to be under threat from inundation, mainly in the local government areas of Lake Macquarie, Gosford Wyong, Wollongong, Shoalhaven and Rockdale.
The maps released yesterday also include projections for low-lying areas in other heavily populated centres, including Melbourne, Brisbane, the Gold Coast and Perth.
See the maps at www.ozcoasts.org.au
Tides to reach new highs in suburban Brisbane
Marissa Calligeros Sydney Morning Herald 17 Dec 10;
One in 100-year floods could instead become annual events among new predictions for how rising sea levels will affect Brisbane over the rest of this century.
Maps released this week show low-lying Brisbane suburbs, including Hemmant, Northgate, Strathpine, Bald Hills and Tingalpa, are most likely to be affected by sea level rises by the year 2100.
Suburbs along the Brisbane River, including Bulimba, New Farm and Woolloongabba, are also at risk of being flooded more frequently.
The maps calculated future water levels across all major capital cities with the use of laser technology, and were developed by the federal Department of Climate Change and the Co-operative Research Centre for Spatial Information.
The projections measured the impact of high tides resulting from seas rising various levels between 0.5 metres by 2100, which is considered unavoidable, and 1.1 metres.
The maps show low-lying suburbs alongside Brisbane's creeks and lakes are most at risk of being inundated by king tides, rather than oceanfront areas.
While the ocean is shown to encroach on some bayside suburbs, areas between Hemmant, Murarrie and Tingalpa are completely underwater.
Most of Brisbane Airport could also be regularly submerged by the end of the century, according to the maps.
Bruce Thom, the chairman of the Australian Coastal Society, said the impact of sea-level rises would be similar to the "Venice effect".
"You do not see one big flood, but a greater frequency of inundation due to high tides," he said.
"Seventy years ago St Mark's Square in Venice, Italy, would only be flooded just a few times a year. Now the square is flooded a couple of hundred times a year."
Research centre chief executive Peter Woodgate warned the maps were only showing the predicted tidal rise and did not take into account the impact of flooding rains and storms, which would occur much more regularly.
“One in 100 year [flooding] events would be occurring once a year,” Dr Woodgate said.
"... If you get flooding coinciding with a high tide, as we do, then the impact will be even worse."
Dr Woodgate said he hoped that within two years the centre would be able to predict flooding levels for every backyard in high-risk Brisbane suburbs.
"We will be able to go door-to-door and talk to residents about what the implications are and what needs to be done," he said.
"It may show that there are homes which are [unsustainable] but we cannot reach that conclusion until will do further detailed analysis.
"We need to think about the protective infrastructure we can put in place, for example, higher levy banks, better drainage systems and different building materials."
Lord Mayor Campbell Newman again warned new residents yesterday of the flooding risks in the city.
"My concern is that over the last 15 years we have had a very dry period and we are now seeing a return to the conditions that prevailed during the 60s and 70s," he told 4BC Radio.
"Since then we have had a lot of people [move to Brisbane] and they have chosen to live near this beautiful, idyllic little creek in suburbia. I'm afraid they don't know that it could turn into a raging torrent and it could actually threaten their property."
Cr Newman encouraged residents to make themselves aware of the flooding risk to their property and take out adequate flood insurance.
