In the latest edition of “What If” by xkcd, Randall Munroe answers a reader whose seven-year-old son wondered how many snowflakes it would take to cover the Earth in six feet of snow. The answer, predictably, gets a bit complicated for a number of factors, including the fact that the snow on the bottom of a pile compresses as more weight is added, making it difficult to know when to measure the stack.
Believe it or not, the National Weather Service has written special guidelines for how often to clear away snow, so everyone can measure it the same way. They use a special snow-measuring board, which is probably just a regular piece of wood, but I like to imagine that they treat it like a precision instrument and store it in a special locked case until it’s needed.
image via xkcd