US faces security threat from climate change - John Kerry

Global warming threatens US security by leaving important military hubs vulnerable to rising seas and possibly fomenting anti-American sentiment, US Senator John Kerry said.

There is "scarcely an instrument of US foreign policy" that was not vulnerable to climate change, which scientists say will raise sea levels by melting glaciers and ice sheets on Greenland and Antarctica, Mr Kerry, a Democrat, said at a Council on Foreign Relations meeting.

US military hubs that could be harmed by rising seas include the island Diego Garcia in the Indian Ocean, a centre for military operations across the Middle East, and Norfolk, Virginia, home to the US Atlantic Fleet.

Mr Kerry said the piers at Norfolk may have to be completely rebuilt if seas rise significantly since they are cemented to the sea floor. The problem was surmountable, but could be "expensive, complicated and perhaps (would even have an impact on) readiness," he said.

The senator's comments came as the US Congress mulls a climate bill that aims to cut emissions of greenhouse gases such as carbon dioxide and methane. The legislation would cut emissions by less than many developing countries want.

Many poor countries want industrialized countries to take deep action on reducing emissions because they enjoyed nearly two centuries of freely doing so during the rise to modernisation.

Mr Kerry, the chairman of the Senate Foreign Relations Committee, said it was "not hard to see" that US inaction on climate change could crystallise anti-American resentment. That was most likely in poor countries across South Asia and Africa that are most vulnerable to climate change's expected floods, heat waves, and droughts, that are also the nations least able to do anything about climate change.