Arctic Summers Could Be Ice-Free by 2040

If you're looking to photograph a polar bear hopping sea ice floes on your next summer cruise, you better hurry because in 30 years, the Arctic Ocean could be free of ice.

Simulating the climate with computer models, researchers analyzed how global warming could affect sea-ice in the future.

The results, published in the Dec. 12 issue of Geophysical Research Letters, indicate that if greenhouse gases continue being released at their current rate, most of the Arctic basin will be ice-free in September by 2040.

• Click here to see an animation of the reduction of Arctic sea ice over several decades.

Additionally, winter ice, now about 12 feet thick, will become less than 3 feet thick.

One previous study predicted that the region will have no summer ice by 2060; another study forecasts that the Arctic will be icy up until 2105.

The rapid meltdown, result of a warming globe, will itself accelerate the heating of the oceans, according to the latest study.

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"As the ice retreats, the ocean transports more heat to the Arctic and the open water absorbs more sunlight, further accelerating the rate of warming and leading to the loss of more ice," said study lead author Marika Holland, a scientists from the National Center for Atmospheric Research. "This is a positive feedback loop with dramatic implications for the entire Arctic region."

Additionally, ocean circulations — affected by global warming — are driving warm ocean currents into the Arctic.

"We have already witnessed major losses in sea ice, but our research suggests that the decrease over the next few decades could be far more dramatic than anything that has happened so far," Holland said. "These changes are surprisingly rapid."

However, the future of the Arctic doesn't have to be so grim: When running simulations projecting lesser amounts of greenhouse gases, the researchers found that the summer sea ice melted at a much slower rate.

"Our research indicates that society can still minimize the impacts on Arctic ice," Holland said.

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