Here’s a primer on the NRCS’s SNOTEL network from Mage Hultstrand writing for the Valley Courier’s Colorado Water 2012 series. Here’s an excerpt:
The Natural Resources Conservation Service (NRCS) installs, operates, and maintains an extensive, automated system to collect snowpack and related climatic data in the Western United States called SNOTEL (for SNOwpack TELemetry.)
The system evolved from NRCS’s Congressional mandate in the mid-1930’s “to measure snowpack in the mountains of the West and forecast the water supply.” The programs began with manual measurements of snow courses; since 1980, SNOTEL has reliably and efficiently collected the data needed to produce water supply forecasts and support resource management activities.
Climate studies, air and water quality investigations, and resource management concerns are all served by the modern SNOTEL network. It may also be the best way to track changing climate over time. The high-elevation locations and broad network of the sites provide data analysis opportunities to researchers, water managers, and emergency managers for natural disasters such as floods.
SNOTEL uses meteor burst communications technology to collect and communicate data in near-real-time. Radio signals are reflected at a steep angle off the ever present band of ionized meteorites existing from about 50 to 75 miles above the earth. Satellites are not involved as the NRCS operates and controls the entire communication system.
More Colorado Water 2012 coverage here.