NASA mission scientist John Sonntag was flying over the Beaufort Sea on April 14 as part of Operation IceBridge when he noticed three strange circles in the ice and snapped a quick pic.
“It was a bit unusual,” said Sonntag, speaking to News/North from Greenland. “I couldn’t recall ever seeing features like that in sea ice, so I wanted to snap a picture of it. Interest in it took off, which was a bit surprising but it's kind of nice.”
The features were spotted close to 80 kilometres northwest of the Mackenzie River Delta.
The first person to really look into the photo was an education outreach worker at NASA’s Goddard Space Flight Centre in Maryland, who asked around and posted the findings to NASA’s Earth Observatory website.
“Once it went up on the Earth Observatory site, it apparently took off,” said Sonntag.
According to the Earth Observatory article, the ice around it appears to be young and pliable. But what caused these circle-like formations isn’t totally clear.
“At the time, the first thing I thought was that it might have had something to do with marine mammals,” said Sonntag. “You know, breathing holes for perhaps seals or whales or something along those lines. A problem with that theory is that those holes were quite a bit bigger than the typical seal breathing hope that we see elsewhere.”
He said it is tough to estimate scale from the P-3 research plane he was in, but he pegs them at several metres wide each.
As the ice was young, soft and travelling about one kilometre per hour, however, these breathing holes could have stretched out into the size he observed, said Sonntag.
Another possible explanation is that as the ice froze it rejected the brine. Salt water does not want to freeze, so it could have been displaced into the water column and then – as saltwater is more dense than regular water – it would sink, displacing warmer sea water that would then come to the top.
“A colleague of mine, more of a sea ice expert than I am, said that he had seen something similar off the coast of Antarctica back in 2009,” said Sonntag. “The photos were indeed pretty similar, but he thought it was caused by that thermodynamic effect.”
Operation IceBridge has been flying over the Arctic, mapping ice on land and sea, for 10 years.
“I can look at the window and almost any given day and see a few things that I can't explain or that don't look immediately familiar to me. They’re sort of minor mysteries, you might call them.”
Sonntag said it’s always nice when the pictures he takes raise enough interest that people start crowd-sourcing solutions.