- NASA scientists on mission IceBridge stumbled upon strange circular patterns in Arctic ice
- The features defy explanation and the researchers claim to have never seen anything like it before
- After a lot of debate, a few explanations were proposed, but with only images in hand, nothing conclusive has been declared
- The circles were found off the coast of Northern Canada in the Arctic Tundra
NASA scientists, during a routine flight over the Arctic, captured images of strange circular formations in the ice and nobody knows what has caused them. This year's Operation IceBridge – NASA's yearly flight over the poles – stumbled upon these strange formations in the ice near Canada's Mackenzie River Delta.
The images were shot by IceBridge mission scientist John Sonntag, reports NASA's Earth Observatory. The main mission for that flight was to observe sea ice in a region that was not very well covered until about 2013, and the discovery of the circles was purely by accident. "We saw these sorta-circular features only for a few minutes today," Sonntag wrote from the field. "I don't recall seeing this sort of thing elsewhere."
Scientists are yet to find out what has caused these strange formations, however, the images have reportedly sparked speculations. Researchers have made it clear that it is not easy to accurately describe the phenomena based on photographs and satellite images alone, "so the following ideas are speculation."
Some features in the ice can be quite easily explained, notes the NASA report. The ice is young, compared to its surroundings and has grown within what was a long, linear area of open water at one point of time. "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.'"
There might be a general left to right motion of new ice as seen by finger rafting, which happens when two floes of thin ice collide and as a result, blocks of ice slide above and below each other, making it look like two hands with interlocking fingers, says Perovich.
"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," said IceBridge project scientist Nathan Kurtz. "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."
Scientists believe that the holes, which as of now seem to be the most difficult to explain, could have been carved out intentionally. Seals are often known to gnaw out holes in thin ice and use them to breathe. Ring seals and Harp seals are known to do this, notes the report. That could also explain the other circular features.
"The encircling features may be due to waves of water washing out over the snow and ice when the seals surface," said Walt Meier, a scientist at the National Snow and Ice Data Center. "Or it could be a sort of drainage feature that results from when the hole is made in the ice."
Another possibility pointed out by Chris Polashenski, a sea ice scientist at the Cold Regions Research and Engineering Laboratory is that the holes could have been caused by convection. "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."
These mysterious circles show how planet Earth never fails to surprise and spur intrigue in even the most seasoned scientists.