This is a true story a collegue once had happen to him,
He landed the skiplane up on a glacier on a particularly clear day, got the punters out on the snow and was explaining that they were standing on about a 100m layer of snow, while under that was about 900m thick of ice. After the speil one particularly vigilant American Lady comes up to him and says:
"Goddamn its a nice day up here. Tell me, does you ever get bad weather up here?"
To which he replied, straight faced as ever, "Well as I was saying we are standing on a 100m layer of snow, which has a 900m layer of compacted ice beneath it, so it would be safe to say that at times the weather can be a tad inclement"