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A snow guage is a Meteorological instrument used to record the depth of snowfall at a specific location. The snow gauge consists of two parts, a Copper Catchment container and the funnel shaped gauge itself. The actual gauge is mounted on a pipe outdoors and is approximately 1.5 m (4 ft 11 in) high, while the container is 51.5 cm (201/4 in) long. When Snow has fallen the container is removed and replaced with a spare. The snow is then melted, while still in the container, and poured into a glass measuring graduate. While the depth of snow is normally measured in Centimetres , the measurement of melted snow (water equivalent) is in Millimetres . An estimate of the snow depth can be obtained by multiplying the water equivalent by ten. The snow gauge suffers from the same problem as that of the Rain Gauge when conditions are windy. If the wind is strong enough, then the snow may be blown across the wind gauge and the amount of snow fallen will be under-reported. However, due to the shape and size of the funnel this is a minor problem. If the wind is very strong and a blizzard occurs then extra snow may be blown into the gauge and the amount of snow fallen will be over-reported. In this case the observer must judge how much of the water is from snow blown into the container and how much is fallen snow. Another problem that occurs, is when both snow and Rain fall before the observer has time to change the gauge. In all of these cases the observer must judge how much of the water is snow and how much is rain. Remote reading gauges, such as used by weather stations, work similarly to rain gauges. They have a large catch area (such as a drum sawn in half, top to bottom) which collects snow until a given weight is collected. When this critical weight is reached, it tips and empties the snow catch. This dumping trips a switch, sending a signal. The collection then repeats. If the catch container has a heater in it, it measures the snow weight accurately. It is also possible to tip based on volume instead of weight, with apropriate fill sensing. Another snow sensor looks like a round bag on the ground. Snow lands on it and the weight is sent off. EXTERNAL LINKS
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