Researchers announced late on Tuesday that the five ice shelves along
The largest shelf is disintegrating and one of the smaller shelves, covering 19 square miles (55 square km), broke away entirely last month.
"Climate models indicate that the greatest changes, the most severe changes, will happen earliest in the highest northern latitudes," said Warwick Vincent, director of the Centre for Northern Studies at
"This will be the starting point for more substantial changes throughout the rest of the planet.... Our indicators are showing us exactly what the climate models predict," he told Reuters in an interview.
Global warming is forecast to generate more damaging weather extremes such as hurricanes, cyclones and floods.
Vincent, who has visited the ice shelves along
His team had estimated that the shelves would lose eight square miles this summer. The true figure was 83 square miles.
"What was extraordinary was just the vast quantity of open water ... you could see open water to the horizon in an area that is typically ice-covered throughout the season," he said.
The Markham Ice Shelf split away from
The Ward Hunt Ice Shelf, at 155 square miles the largest of the remaining four shelves, is disintegrating.
"Clearly the long-term viability of that ice shelf is now actually short-term," said Vincent.
The peak temperature the team recorded was 67.5 degrees Fahrenheit (19.7 degrees Celsius), far above the average of 46 degrees Fahrenheit.
Vincent said he had no doubt that global warming was caused in part by human activity.
"I think we're at a point where it is not stoppable but it can be slowed down. And if you think about the magnitude of effects on our society, then we really need to buy ourselves more time to get ready for some very substantial changes that are ahead," he said.
Scientists say the shelves, which contain unique microscopic ecosystems that have not yet been studied, will not be replaced because they took so long to form.
"More and more, we're realizing that it is microscopic life that really dominates the biodiversity of planet Earth ... we really need to understand what that biodiversity is," said Vincent.