DIY methane chamber designs inspire research groups across the country

Research Assistant Zoë Dietrich’s low-cost chambers are making carbon flux sampling more accessible

jillian greene stands in the water with her chamber based on zoe dietrich's designs

Jillian Greene deploys her methane monitoring chamber based on designs by Zoë Dietrich.

photo courtesy of Jillian Greene

The MacGyver session at the annual American Geophysical Union (AGU) conference is full to the brim with scientists showing off blinking circuit boards and 3D-printed mechanisms. Research Assistant, Zoë Dietrich, stands in front of her poster and a plexiglass cube sprouting wires. As she speaks, a whizzing sound emanates from the box as it lifts itself up on one side, holding itself open long enough to flush the interior with air from the room. A laptop screen reads out numbers from the sensors in the box, detailing changes in the concentrations of carbon dioxide and methane within.

Dietrich constructed this device herself. It’s a low-cost, autonomous, solar-powered chamber designed to float on water and measure the flow of carbon into and out of the water. Dietrich has spent the past 1.5 years testing and troubleshooting various prototypes, and has already begun deploying models at research sites in Brazil and Alaska. Now she’s sharing her work with the broader scientific community in hopes of encouraging others to build their own versions.

dietrich presents to a crowd at AGU standing in front of a poster of her work

Dietrich presents her poster at AGU in San Francisco, CA.

photo courtesy of Zoë Dietrich

“One of the goals of the chamber project is to make the construction very accessible so that scientists like me, without formal engineering training or background, can build the chambers pretty easily,” says Dietrich.

This was good news for Grand Valley University masters student, Jillian Greene, and her professor Dr. Sean Woznicki, who encountered Dietrich and her chambers at AGU. Though neither of them had experience with mechanical or electrical engineering, they knew immediately a device like Dietrich’s could be invaluable to their research.

Greene’s project involves sampling carbon emissions at drowned river mouth estuaries connected to Lake Michigan. She and Woznicki will then correlate that data with other ecological characteristics gleaned from satellite imagery. There are over one hundred of these freshwater estuary-like features around the region, and Greene and Woznicki are hoping to paint a complete picture of their cumulative role in carbon cycling. 

“Originally, I was going to manually sample and quantify with a gas chromatograph,” Greene says. That’s a time-consuming process that limits the amount of data one team can collect. With the chambers, however, Greene can collect emissions data every 30 seconds—greatly expanding the amount of data she’ll be able to incorporate into her models.

“This is going to make our model a lot more robust and hopefully applicable to other drowned river mouth estuaries in the region,” says Greene.

Greene and her research team have already created and deployed 6 chambers. Since AGU, she has been in contact with Dietrich, troubleshooting issues as they arise and learning an entirely new set of skills as she goes.

“[the team] has learned how to solder, how to interpret the circuit diagrams, problem solve, and adjust for our kind of unique systems that we’re looking at,” says Woznicki. “It’s really been exciting to use Zoë’s design as a learning experience for masters and undergrad students.”

Jillian's floating chamber moored to several stakes in a lake in michigan

Greene’s chamber floating at one of her test sites.

photo by Jillian Greene

Dietrich has had other groups at Colgate University and the University of California, Berkeley reach out to her as well, and she is planning to publish a paper this fall that will include detailed instructions for anyone else  to construct their own chambers. She’s already shared preliminary drafts of the step-by-step instructions, including photos, diagrams, and tips, as well as programming and data-processing code and a specific materials list with the other research groups. In turn, they have provided her with helpful revisions and ideas for new modifications. Dietrich is excited about the prospect of the designs being implemented by more people. More chambers means more data, which benefits the entire scientific community.

“Our sampling of carbon right now is limited by expensive instruments and where people can go and who has access to these resources,” says Dietrich. “But the goal of this project is to be low cost and more accessible to a broader set of researchers. The chambers are  autonomous, and so are accessible to places and times that aren’t otherwise being sampled right now. And taking that a step further, we need to make them accessible to be built by anyone.”