Well, when the current is off, i could imagine a freeze over to happen quite fast if the temperatures are low enough. But once the current starts picking up again, the ice needs to be thick enough to not get sucked away.
I would love to know some real numbers on those variables.
How cold must it be for how long to freeze a sustainable sea ice surface? How does an active current influence these numbers?
All I know is, don't go looking for those temperatures today. For most of the last 48 hours the temperature in Alert has been above freezing, hitting a high of 4.7 degrees the morning of the 28th. Everything outside right now is melting, there's water dripping from the roof of the lab. The forecast says we're going to see continued high temperatures through most of the week.
Admittedly my experience is limited, but I've never seen weather like this so late in the season. 5 degrees is warmer than most days in the middle of summer, and we're only two weeks away from the final sunset of the year...
I'm up here until the first week of January, I'll be watching this thread closely in the meantime. Judging by the large area of open water visible off the coast here, I have serious doubts about the ability of the ice bridge to form this winter. The floes are simply too sparse and thin.