USA TODAY International Edition
‘Mysterious’ hole appears in sea ice near Antarctica
A huge, mysterious hole has been spotted in sea ice near Antarctica, researchers reported this week.
The hole, which was detected about a month ago, is roughly 30,000 square miles, or the size of the state of Maine. It’s the largest hole spotted in the Weddell Sea since the 1970s, scientists say.
“In the depths of winter, for more than a month, we’ve had this area of open water,” Kent Moore, professor of physics at the University of Toronto-Mississauga, told National Geographic.
The months of June, July and August are winter in the Southern Hemisphere.
This is the second year in a row that scientists have seen such a massive hole in Antarctica’s sea ice, though this one is bigger than the one from last year.
The phenomenon is called a “polynya,” which is an area of persistent open water where one would expect to find solid sea ice, according to the National Snow and Ice Data Center.
The hole was detected using a robotic float that’s capable of operating underneath sea ice.
Satellite images further confirmed its appearance.
Moore worked with members of the Southern Ocean Carbon and Climate Observations and Modeling project to investigate polynyas and their climate impacts.
“It’s just remarkable that this polynya went away for 40 years and then came back,” Moore said.
Without the insulating effect of sea ice cover, a polynya allows the atmosphere and ocean to exchange heat, momentum and moisture, leading to significant impacts on the climate.