(ARIZONA'S WEATHER AUTHORITY) -- Rain gauges aren't new, but they're getting better every day. History dates rudimentary rain collectors to 400 BCE in Greece and India. And in the 1400s, rain collectors were used regularly in Korea in an effort to coordinate the best time to plant.
Rain gauges aren't very complicated, or at least they don't have to be. An easy trick to know how much rain has fallen at your house is to use a tuna can (or any jar or can with the same size opening at the top and bottom). After it rains, stick a ruler in there, and you have a pretty good idea of how much rain fell.
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As one side fills up, gravity tips the bucket and the rainfall is measured. Then the other side starts filling up. That technology hasn't changed much over the years. Here is a photo of an old-time, early-1900s tipping bucket rain gauge from my collection; it's made mainly of copper.
And then there's the Big Daddy of them all, the standard copper weather gauge the National Weather Bureau, now Weather Service, used for more than a century. In fact, in many locations, this type of rain collector, with its 8-inch opening, is still in use, but you have to measure by hand.
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See all the fins around the opening? That's supposed to help counter the effects of wind on rain but guess what? Inside of all of that, there's a tipping bucket mechanism counting our rainfall 24/7.
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