Anne Poukka, age 9, of Duluth, Minn., for her question:

HOW DO THEY MEASURE SNOWFALL?

One way is to take a ruler and poke it down to measure the thickness of the snow on the ground. Maybe the latest snowfall was two inches or three inches deep or even deeper. However, the weathermen need to know a lot more about the amount of winter snows that fall over a vast region. Come spring, all that melting snow will run away to feed the crops in the fields.

As we know, a snowfall piles up along walls and fencesand spreads itself thinner over flat, open spaces. So the weathermen take sample measurements from far and wide. Then they melt their samples and measure the amount of actual water. If a new layer of fluffy light snow is six inches deep, its measurement equals about one inch of rainfall. Layers of heavy old winter snows equal more inches of rain. Or we can use a ruler to measure the thickness of the actual snow. However, we must compare the deep snow drifts with the thin patches.