Antarctica heading for climate crisis if carbon emissions aren't cut

Scientists say Antarctic ice sheet has physical tipping points, beyond which ice loss can accelerate out of control.

While U.S. Secretary of State Antony Blinken draws attention to climate change in the Arctic at meetings with other national officials this week in Iceland, an even greater threat looms on the other side of the planet.

New research shows it is Antarctica that may force a reckoning between the choices countries make today about greenhouse gas emissions and the future survival of their coastlines and coastal cities, from New York to Shanghai.

That reckoning may come much sooner than people realize.

The Arctic is losing ice as global temperatures rise, and that is