Mysterious, Maine-sized hole appears in Antarctica sea ice cover

"Sea ice and clouds blanket the Weddell Sea around Antarctica in this satellite image from Sept. 25, 2017. A SOCCOM float surfaced within the 60,000 km2 polynya (center) at the location marked in yellow." (Image from MODIS-Aqua via NASA Worldview; sea ice contours from AMSR2 ASI via University of Bremen; caption provided by SOCCOM)

WASHINGTON (Sinclair Broadcast Group) - For the last month, Antarctica's sea ice cover has been sporting a vast, mysterious hole, according to the Princeton University-based Southern Ocean Carbon and Climate Observations and Modeling program.

National Geographic reported Wednesday that the giant opening is as big as the state of Maine -- approximately 30,000 square miles at its biggest.

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SOCCOM says the newly discovered hole, called a polynya, is the largest seen in the Weddell Sea since the 1970s.

A smaller polynya formed in the region last year, according to National Geographic.

University of Toronto physics professor Kent Moore tells NatGeo that researchers are investigating what causes polynyas to form.