CSO is a citizen science campaign to measure snow.

Make your backcountry travels count! We need your help measuring snow depths in mountain places too vast for researchers to monitor.

Your observations help us predict snow conditions and improve safety for mountain travelers.

Upcoming events

January 17, 2022
  • Weekend Warrior Data Drive

    January 17 - March 20, 2022
    Mountain Hub or Snow Pilot (United States/Canada)

    This winter we’re launching a new contest format with the Weekend Warrior Data Drive contest — a new winner announced every week during January 17 – March 20, 2022. What’s in the prize pot? Awesome backpacks from Backcountry Access!

    Rules for participation: Snow depth observations should be measured at least 100 m (> 300 ft) apart and in undisturbed snow in an non-urban area, and submitted in Mountain Hub or Snow Pilot. Further details on how to measure snow here.

    Every Monday during this time period, we’ll review snow depth observations submitted the previous week (Mon-Sun) and pick the individual who submitted most observations during that week as the winner.

    Note: An individual can only be a winner once during this contest. Contest will run for 9 weeks total. 

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Observations to date

Our database is growing and improving, thanks to you


Join us and help improve snow science!