An Ice-Free North Pole This Year?

This summer could see the North Pole ice-free for the first time since the Pleistocene era, say scientists at the University of Colorado at Boulder.

Satellite data accumulated by CU's National Snow and Ice Data Center show that relatively young sea ice that is no more than about 60 inches deep and much more susceptible to melting away now comprises only 72 percent of the Arctic ice sheet. Using that estimate, scientists at the center see a 50 percent chance that ice at the highest point in the Arctic will melt by the summer's end.

Center research Andy Mahoney says the weather will determine whether the prediction turns out to be accurate.

"It will probably come down to how cloudy it is this summer," Mahoney told ABC News. "If there's clear skies and if atmospheric patterns resemble last year's, you're going to see a lot more melt."

The loss of Arctic sea ice would likely cause the planet's atmosphere to heat up even more because the ice pack bounces the sun's rays back into space. This reflective property, known as albedo, also prevents the rays from reaching the ocean, where heat is absorbed.

Therefore, a loss of sea ice results in warmer ocean waters, which in turn increases the melt of the ice even more.

"Losing the ice sheet means losing an important way of cooling down," Mahoney told ABC News. "As a result, global warming would accelerate as the ice retreats."