Each year for the past 10 years NASA has conducted airborne missions over both of Earth’s polar regions to map land and sea ice. On April 14, as part of this year’s mission, scientist John Sonntag noticed something he’d never seen before. There were random circles poking through the ice exposing the ocean water below.
So, as they flew about 50 miles northwest of Canada’s Mackenzie River Delta, Sonntag snapped a picture of the strange circles from the window of the plane.
Then he wrote, “We saw these sorta-circular features only for a few minutes today. I don’t recall seeing this sort of thing elsewhere.”
Here’s more from WattsUpWithThat.com:
The features are more of a curiosity than anything else. The main purpose of the flight that day was to make observations of sea ice in an area that lacked coverage by the mission prior to 2013. Still, the image sparked a fair amount of intrigue, so we set out to see what we could learn. That’s not always easy based on a photograph or satellite image alone, so the following ideas are speculation.
Some aspects of the image are easy to explain. The sea ice here is clearly young ice growing within what was once a long, linear area of open water, or lead. “The ice is likely thin, soft, and mushy and somewhat pliable,” said Don Perovich, a sea ice geophysicist at Dartmouth College. “This can be seen in the wave-like features in front of the middle ‘amoeba.’”
Nathan Kurtz, a project scientist on the mission also added:
“It’s definitely an area of thin ice, as you can see finger rafting near the holes and the color is gray enough to indicate little snow cover. I’m not sure what kind of dynamics could lead to the semi-circle shaped features surrounding the holes. I have never seen anything like that before.”
This is usually the place where conspiracy theorist and paranormal enthusiasts float out all sorts of theories that can never be proven or disproven. Fortunately Walt Meier, a scientist at the National Snow and Ice Data Center, stepped in with a more earth bound possibility.
He suggests that the holes are breathing holes created by seals. Apparently, seals will gnaw through areas of thin ice to create breathing holes where they can surface and breathe.
“The encircling features may be due to waves of water washing out over the snow and ice when the seals surface,” Meier said. “Or it could be a sort of drainage feature that results from when the hole is made in the ice.”
An alternative theory is that these holes are convection holes.
“This is in pretty shallow water generally, so there is every chance this is just ‘warm springs’ or seeps of ground water flowing from the mountains inland that make their presence known in this particular area,” said Chris Shuman, a University of Maryland at Baltimore County glaciologist based at NASA’s Goddard Space Flight Center.
“The other possibility is that warmer water from Beaufort currents or out of the Mackenzie River is finding its way to the surface due to interacting with the bathymetry, just the way some polynyas form.”
Polynyas are stretches of open water that are surrounded by ice.
Both of these theories certainly seem plausible, though, it seems like the breathing hole explanation might be the most plausible one.