As far as “gas holes” in the ice, I have been quite observant about ice the last ten years or so, trying to prep the ice for hockey with friends. It is a constant struggle with ice dynamics in a warming world!
Wind appears to be the main culprit with a water column that is still above 39 degrees below the ice in the early season. The ice cracks from flexing due to wind, and the pulsating surface of the ice due to wind pumps water up and down the crack until you get a larger opening. Gas bubbles and warmer waters lift to the backside of the ice, and are pumped towards the hole. Where the gas and warmer waters flow, you get a cool looking river-like pattern where it melts channels.
This process stops, at least in my pond, once the water below the ice chills enough, and the ice is thick enough to resist the wind. But if we get a thaw and warm water is inserted beneath the ice, the process starts again.
Earlier this winter we had about 3” of ice, mostly bare. The wind came up and created holes all over it. I could watch as wind gusts came and went which resulted in water pumping up and down those holes to spread across the ice. Needless to say that ice was about as dangerous as it gets.
