Australian cities could be wiped out by rising sea levels, says National Geographic FIVE major cities will be wiped out and Australia will be inundated by an inland sea the size of Ireland, maps showing the devastating effect of global warming have revealed. No longer a nation girt by sea, we could well be a nation consumed by sea. The interactive maps - released by National Geographic - demonstrate the catastrophic effect Earth's ice could cause if it melted and flowed into the oceans and seas. The maps predict that the nation's coastal fringe - home to four out of five Australians - will be hit by rising sea levels. Sydney, Melbourne, Adelaide, Darwin and Perth would all be devastated by the catastrophic seas rises. And we are not alone. Sea levels could rise by nearly 70 metres, devouring cities - such as New York - and even countries while drastically altering continents. The maps reveal South Australia's Lake Eyre would become a massive inland sea, with rising sea water wiping out the lower reaches of the Murray River and surrounds. The changes are predicted to happen over thousands of years unless steps are taken to combat rising temperatures from climate change. "There are more than five million cubic miles of ice on Earth, and some scientists say it would take more than 5000 years to melt it all," National Geographic's website says. In the US, New York City would sink beneath the waves along with much of the heavily populated east coast. In Europe, London and Venice would be a distant memories, while the rising seas would dramatically increase the size of the Black and Caspian Seas. Bangladesh and its 160 million inhabitants would be wiped off the face of the world and 600 million Chinese would be forced to relocate.