Davies, Mary Ann. 2002. Windshields for Precipitation Gauges and Improved Measurement Techniques for Snowfall. 0225 2325. Missoula, MT: U.S. Department of Agriculture, Forest Service, National Technology and Development Program. 6 p.
Describes the results of several studies that have shown that most windshields used with precipitation gauges are not very effective. The standard by which windshields are measured is the double fence intercomparison reference gauge. That windshield consists of two fences. The inner fence is 4 meters in diameter. The outer fence is 12 meters in diameter. Other windshields that are discussed include the Nipher shield, the Alter shield, and the Wyoming shield. The gauge that seems to be the most popular for measuring snowfall in Canada and the United States is the Geonor precipitation gauge. Glycol solution is in a bucket that is suspended by wires. As snow falls and melts in the glycol solution, the mass increases. The wires stretch and begin to vibrate, producing an electromagnetic field that is picked up by the bucket’s sensor. The strength of the electromagnetic field depends on the mass in the bucket, allowing the contents to be measured accurately. Keywords: deposition, instruments, meteorology, precipitation, snow describes the results of several studies that have shown that most windshields used with precipitation gauges are not very effective. The standard by which windshields are measured is the double fence intercomparison reference gauge. That windshield consists of two fences. The inner fence is 4 meters in diameter. The outer fence is 12 meters in diameter. Other windshields that are discussed include the Nipher shield, the Alter shield, and the Wyoming shield. The gauge that seems to be the most popular for measuring snowfall in Canada and the United States is the Geonor precipitation gauge. Glycol solution is in a bucket that is suspended by wires. As snow falls and melts in the glycol solution, the mass increases. The wires stretch and begin to vibrate, producing an electromagnetic field that is picked up by the bucket’s sensor. The strength of the electromagnetic field depends on the mass in the bucket, allowing the contents to be measured accurately.
Keywords: deposition, instruments, meterology, precipitation, snow
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