Penguins in Antarctica. The US  study suggests sea levels could rise 1.5 metres by 2100, posing an even greater threat to cities from New York to Shanghai. Photograph: Alejandro Vejar/Chilean Navy/EPA

Sea levels could rise 50cm more this century than had been expected, according to a report published on Wednesday which found that Antarctic ice will (...)

Dr Anders Levermann told a side event at the UN climate talks in Bonn that the Earth has entered a new era of irreversible climate change: “West Antarctica has tipped and there isn’t anything we can do about it.” Photograph: Reuters/Australian Antarctic Division

World leaders need to ensure that global warming is kept low enough to avoid “pulling the plug” on vast ice shelves in Antarctica, thereby causing (...)