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Arctic sea ice dips to record winter low

Arctic sea ice temperatures have dipped to a record winter low, pointing to an overheating world, scientists say.

The frigid top of the Earth just set yet another record for low levels of sea ice in what scientists say is a signal of an overheating world.

The extent of floating ice in the Arctic hit a new low for winter: 14.42 million square kilometres.

That's about 97,000 square kilometres - an area about the size of Maine - below 2015's record.

Last year had a shade more than 2015, but nearly a tied record.

This puts the Arctic in a "deep hole" as the crucial spring and summer melt season starts and more regions will likely be ice-free, said Mark Serreze, director of the National Snow and Ice Data Centre in Colorado, which released the findings Wednesday.

"It's a key part of the Earth's climate system and we're losing it," he said.

"We're losing the ice in all seasons now."

At the other end of the world, Antarctica, where sea ice reaches its lowest point of the year in March, also hit a record low mark.

Antarctic sea ice varies widely unlike Arctic sea ice, which has steadily decreased.

The ice data centre measures how wide sea ice extends based on satellite imagery.

It's harder to measure the thickness and overall volume, but data from the University of Washington show that as of late last month ice volume levels were down 42 per cent from 1979, said polar science centre chief Axel Schweiger .

Several scientists called the sea ice loss disturbing.

"It's evidence that the climate at the top of the world continues to change faster than anywhere else on Earth with impacts to us that are still frankly unknown," Pennsylvania State University meteorology professor and retired admiral David W. Titley said.

Scientists blame a combination of natural random weather and man-made global warming from the burning of coal, oil and gas.

The winter of 2016-2017 was unusually toasty and the Arctic saw three "extreme heat waves," Serreze said.

Texas Tech climate scientist Katharine Hayhoe said the Arctic is the canary in the climate's coal mine.

"What happens in the Arctic doesn't stay in the Arctic," Ms Hayhoe said.

"This entire planet is interconnected."