Community Collaborative Rain, Hail & Snow Network (CoCoRaHS)


October 1st, 2012

CoCoRaHS, the Community Collaborative Rain, Hail and Snow Network, is a citizen science project based at Colorado State University (CSU), led by Principal Investigator Nolan Doesken and funded in part by the National Science Foundation (DRL-1010888). The project was created to enhance the research efforts of scientists and promote climate literacy among the public by engaging volunteers in precipitation-monitoring activities.

CoCoRaHS is a program where volunteers collect high-resolution precipitation data to aid STEM researchers and professionals with hydrologic monitoring and prediction. Besides providing high quality data, CoCoRaHS also promotes education and climate literacy to the community with the use of daily messages, newsletters, webinars, educational videos, and outreach events. CoCoRaHS started in 1997 at CSU in response to a devastating local flash flood, and has since grown to become a network of over 16,000 observers in 50 U.S. States and Manitoba, Canada. Each state network is managed by a coordinator which is a volunteer position usually held by an official at NOAA’s National Weather Service (NWS) or under the authority of the office of the state climatologist.

Program volunteers are equipped with a high capacity, 4-inch-diameter clear plastic rain gauge with a funnel and inner calibrated tube that accommodates rainfall measurements to the nearest 0.01 inch, meeting the NWS specifications for year-round precipitation measurements. When used for measuring snow, the funnel and inner tube are removed and snowfall is collected in the larger outer cylinder, allowing for a reading of the water content in the snow. This particular measurement is of great importance to scientists studying snow and ice, as well as local water managers who are in charge of forecasting future water supplies.

Volunteers enter their data each morning via the CoCoRaHS website, where the data are then immediately available for viewing (in the form of maps and data tables) or for download. During hail or heavy/unusual precipitation events, volunteers can submit real-time reports which are immediately directed to the appropriate local NWS forecast office to aid in issuing and verifying severe weather and flash flood warnings. All data are checked for errors and archived, and are publicly available for current or historic use.

CoCoRaHS is currently in a broad implementation phase to equip, train and grow their burgeoning network of citizen scientists to be neighborhood climate data analysts and is enhancing tools for data analysis and inquiry. This includes next generation programs and instruments to enter, store, manage, analyze, and visualize data and collecting additional evapo-transpiration data to improve scientists’ water cycle models. CoCoRaHS is expanding their network of citizen scientists with new training materials and communications strategies that integrate social networking and mobile devices, and engaging K-12 audiences with a standards-aligned education outreach component that has a national reach.

These enhancements will allow new collaborations between museums and science centers, outreach to underserved audiences, and recruitment of new volunteers for the CoCoRaHS network. Through a partnership with the National Association of Conservation Districts, the project will conduct educational outreach to all 3,140 counties in the United States. Anticipated results include increased numbers of people, particularly younger people, participating in precipitation-monitoring activities, and increased participant knowledge, skills, interest, and involvement in climate science and scientific inquiry. Participants are trained through a variety of on-line materials including slideshows, written instructions, YouTube videos, and recorded webinars, and by attending scheduled in-person training sessions hosted by local CoCoRaHS coordinators.

David Heil and Associates are the external evaluators for CoCoRaHS. Formative evaluation of the project is currently underway, and some of the data collected in 2012 will also be used for summative evaluation of outcomes and impacts. Because a major question for both the CoCoRaHS project and the field of Citizen Science in general is how to engage new audiences while retaining current participants in the collection of scientific data, much of the evaluation’s focus is to explore the needs and interests of prospective, as well as current, volunteers.

Findings from the Year 1 evaluation report indicate that promising recruitment and retention strategies include: maintaining an engaging and useful website; keeping the process for participation easy and informative; providing multiple opportunities for learning about climate and weather; clearly communicating the value of, and uses for, the data that volunteers provide; and focusing on audiences who are likely to be interested in weather and/or encouraging that interest in potential new audiences.