A new study from the Scripps Institution of Oceanography reveals a troubling trend in the Arctic: as the planet warms and the ice caps melt, the Earth is losing its ability to reflect heat back into space. This natural amount of light reflected from planet’s surface, called albedo, is incredibly important. In the 70s, scientists discovered that a full 52 percent of the sun’s rays simply bounced off the surface of the Arctic, with only 48 percent absorbed. But by 2011, the situation had flipped, with only 48 percent of the light reflected back into space.
While that may not seem like a drastic shift, it adds up over time. Not only is the declining Arctic albedo causing the planet to warm at a higher rate, but scientists calculate that the extra solar energy absorbed into the atmosphere is equal to about a quarter of what’s been trapped by greenhouse gasses. That’s not insignificant, and as the ice caps melt, it’s only going to get worse. This phenomenon has inspired some to propose blasting reflective chemicals into the atmosphere to block the sun’s rays — a solution Al Gore called “insane, utterly mad, and delusional in the extreme” earlier this year.
Melting ice isn’t the only reason the Arctic is absorbing more heat than in the past — soot and other pollution are also settling on the remaining snow and ice and reducing its reflective abilities. The findings have been published in the Proceedings of the National Academy of Sciences of the United States of America.
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