Standpipe storage precipitation gauge
From AMS Glossary
standpipe storage precipitation gauge
A precipitation gauge comprising a tall pipe 30.5 cm (12 in.) in diameter designed especially to measure the water content of snow in remote mountainous areas for unattended operation; part of a SNOTEL site.
The bottom contains a known amount of an oil–antifreeze mixture. The oil prevents evaporation and the antifreeze melts the snow. A pressure transducer converts the oil–antifreeze–water mixture into a calibrated water depth. Daily changes in depth provide seasonal and annual accumulations.