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Highlights Archive
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Highlights Archive


GRANTEE:Citizen Scientists are "Cuckoo for CoCoRaHS"!

Published March 2012


CoCoRaHS (the Community Collaborative Rain, Hail and Snow network) is a nationwide "citizen science" project, supported by an Environmental Literacy Grant (ELG) award, that engages thousands of people (currently over 15,000 active volunteers) of all ages in measuring and investigating precipitation. Participants use low-cost, high-capacity rain gauges along with rulers and foil-wrapped Styrofoam "hail pads" to accurately measure rain, hail and snow.

Map of CoCoRaHS volunteer-collected precipitation data for January 23, 2012. Source:

The measurement and communication of precipitation information are lowest common denominators for connecting the public to atmospheric and hydrologic processes and impacts. Precipitation affects the lives and activities of nearly everyone. Precipitation is episodic and sometimes destructive. Its characteristics change with the seasons. It may be the most noticeable, variable and impactful element of our climate.

Volunteer networks, such as with National Weather Service's Cooperative Observer Program, have a long history in NOAA. Volunteered data are used extensively within the agency. What is unique about CoCoRaHS is the use of Internet technologies along with social networking and great ties with local National Weather Service Offices and State Climate Offices to effectively connect people from across the entire country with environmental science, weather prediction, the climate system and the scientific community.

CoCoRaHS has twice received ELG awards from the NOAA Office of Education. The current award is helping CoCoRaHS enhance the "volunteer experience" by improving access to and visualization of the data collected by volunteers. This allows the volunteers to be data analysts, not just collectors. New mapping capabilities are being added to view both recent and historic national, regional or local precipitation. Through collaborations with Oregon State University, volunteers will soon be able to view their recent precipitation data in context with 100-year geospatial time series of precipitation data. Graphing capabilities have been added and more features are planned. A very exciting new addition for 2012 is the measurement of "reference evapotranspiration" to improve the visualization and understanding of the water cycle in action.

Thousands of new volunteers will be recruited and trained during the next two years with emphasis on reaching younger audiences (the most common age range for current volunteers is 45-80 years old). Facebook and Twitter have already become effective recruiting tools. Animations are being developed and disseminated via YouTube to introduce CoCoRaHS to broader audiences. Live and archived webinars are becoming a mainstay for volunteer training. An educational series of monthly webinars called CoCoRaHS WxTalk provides opportunities for CoCoRaHS participants to learn special topics directly from top atmospheric scientists and educators.

CoCoRaHS welcomes anyone with an interest in learning about precipitation. Please sign up today at: (

More information on this exciting project, including how to join, is available from their web site.


Mark Anderson of Univ. of Nebraska, a CoCoRaHS volunteer, explains how to use a rain guage. Credit:Henry Reges/CoCoRaHS

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