>>1273749Well heat travels upwards so it doesn't melt a hole straight down. But some of the radiating heat does melt the snow/ice below into a shallow puddle of water, which can be enough to stifle your fire.
So the best way to do it is build your fire ontop of a base of other firewood, then you're good to go.
And no, the puddle only goes to half an inch deep at most so you don't need to worry about cracking the ice and falling through
