Climate Corner: Trust me (you?); we collect the data

May 6, 2023

Jonathan Brier

My name is Jonathan Brier, I’m a resident of Marietta and an information scientist, but I started as a citizen scientist as a teenager. I didn’t know what I was doing would be called citizen science until years later. I still identify as a citizen scientist to this day, even though I earned a Master of Science degree in Information from the University of Michigan and spent 7.5 years pursuing a PhD in Information Studies at the University of Maryland. My reason for these studies was to help make citizen science more effective and reach more people. I’d like to introduce you to one of thousands I’ve explored.

What is citizen science, you might ask? Well, the Citizen Science Association (“”> uses the definition “Citizen science is the involvement of the public in scientific research — whether community-driven research or global investigations.” To me citizen science is an umbrella term encompassing many practices of the public engaging in science. Birders, aka people really into birdwatching (like my fiancee), often talk about the eBird citizen science project and tracking what they’ve seen and where. eBird applies sophisticated statistical checks for data quality and trust. The United Nations has identified citizen science as important to tackling the sustainable development goals and data needs ( There are growing data needs in many areas of science. Climate science is where I’m focusing today.

The project I would like to share with you is CoCoRaHS ( It is pronounced like hot chocolate ‘coco’ and ‘ra’s like the Egyptian deity, but plural. CoCoRaHS stands for Community Collaborative Rain, Hail and Snow Network and started at the Colorado Climate Center at Colorado State University in 1998. It now has thousands of people all over North America. Ohio joined in February 2009 and West Virginia in May 2009.

CoCoRaHS participants are important as they provide local coverage of precipitation for where they live. The minimum requirements are: (a) buy one of the 4″ standard rain gauges, (b) apply to join, and (c) attend or watch a training session.

There are a few types of measurements and other tools, but the 4″ rain gauge is the basic equipment to start and costs $48. The basics to participating are to check, record, and empty the rain gauge at the same time each day and to keep a written record of your data as backup. Enter your data on the website. Quality checks are performed once your record is in the central database and they may ask you to double check your written log if something doesn’t look right. Additional low-cost materials like a ruler, wood dowel, and square of plywood painted white are other tools used in monitoring depending on the precipitation.

What data matters? Reports of zero precipitation at the same time frame each day matters as much as accurate measurement of precipitation. Why? As the report of zero still is data to confirm nothing fell instead of no data, which is a gap.

View the latest data from CoCoRaHS participants by visiting and see a report near you. By adding your backyard, farm, or other data from a location you monitor means that weather forecast models have more reliable data to base their statistical estimates from and climate models can compare their prediction to actual data over time at specific locations. Manual weather records such as ship logs, which include weather data, are one way climate scientists are able to create models of past weather and understand how our climate changes over time.

CoCoRaHS data complements automated weather stations such as those found at airports, NOAA monitoring sites, personal weather station networks like Weather Underground’s Personal Weather Station Network (, and other monitoring sites. Better data means improved forecasts for weather forecasts and crops and maybe you know someone who already relies on this data. As a community we can collect the data, trust the data because we know how it is collected, and maybe better understand the science of climate science.

Does CoCoRaHS interest you? Visit and sign up visit


Jonathan Brier is a Marietta resident, information scientist, and an Eagle Scout. He is a member of the Citizen Science Association, Association of Computing Machinery, American Association for the Advancement of Science, OpenStreetMap US, Mid-Ohio Valley Climate Action, and a Wikipedia contributor. If you want to know more about citizen science or to reach him, visit or email: