The MICADAS touch — carbon dating for climate solutions

While a single piece of technology isn’t going to solve the climate crisis, there’s a new instrument at Yale that is expected to help dozens of scientists assess the benefits of natural climate solutions to alleviate catastrophic global warming.

In 2023, Yale will become one of the few research universities in the United States to operate a miniaturized, accelerator mass spectrometer (AMS) designed specifically to work with the radioactive isotope ¹⁴C. The cutting-edge tech — called a Mini Carbon Dating System, or MICADAS — will open new research pathways for Yale scientists conducting emerging research on climate solutions, such as mimicking natural carbon capture and more accurately understanding the role of carbon in different ecosystems.

The new instrument will also be available for applications in archaeology, museum curation, materials science, biomedicine, and forensics.

The Yale Center for Natural Carbon Capture, a key element of Yale’s Planetary Solutions Project, purchased MICADAS. The instrument will be housed at the Yale Analytical and Stable Isotope Center (YASIC), a campus core facility directed by the Office of the Provost and located on Science Hill.

“The MICADAS will help advance fundamental understanding of important ecosystem processes and aid researchers, both at Yale and beyond, in evaluating the efficacy of natural climate solutions by quantifying carbon uptake in projects that seek to use ecosystems to capture carbon,” said Liza Comita, professor of tropical forest ecology at the Yale School of the Environment and co-director of the Yale Center for Natural Carbon Capture.

Carbon capture is likely to be a key element of global efforts to stem climate change. Earth already has several natural processes for absorbing and storing carbon, such as photosynthesis, which enables plants to take in carbon dioxide and store carbon in biomass; and mineral weathering, which locks carbon in rocks. Ongoing Yale research — with help from MICADAS — seeks to mimic these processes.

The new tech also contributes to Yale’s ongoing commitment to invest in cutting-edge core facilities that support science and engineering research across disciplines.

Brad Erkkila, facility manager for YASIC, and Peter Raymond, faculty director of YASIC, professor of ecosystem ecology at the Yale School of the Environment, and a guiding force in encouraging Yale to purchase the new technology, spoke with Yale News about how MICADAS works and how it will enable Yale scientists to advance climate change research across a variety of disciplines.

Perhaps we should start by talking about how this technology relates to climate change research.

Peter Raymond: Many scientists now argue that carbon dioxide removal will be needed to avoid catastrophic warming. One component of carbon dioxide removal is natural climate solutions [NCS] projects, which try to facilitate carbon capture within an ecosystem or attempt to improve methane emissions. The management and investment communities are moving forward with billions of dollars in NCS projects, but we still have a great deal of work to do in terms of understanding how much carbon dioxide these projects can remove. In the coming years there will be a myriad of demonstration projects trying to do this work through monitoring and verification.

That’s where ¹⁴C comes in, correct?

Brad Erkkila: Yes. Isotopes of carbon are a powerful tool used to quantify ecosystem carbon budgets and dynamics. There are two isotopes of carbon — ¹³C, a stable isotope that makes up about 1% of all carbon in ecosystems, and ¹⁴C, a radioactive isotope with a half-life of about 5,700 years that is present at a concentration of about one in every 10¹² carbon atoms in active carbon reservoirs such as plants.

Both isotopes have been used to understand the Earth’s carbon budget for decades. The use of ¹³C, however, is much more prevalent, with hundreds of laboratories in the U.S. equipped with stable isotope mass spectrometers. Currently, there are only a handful of U.S. labs that can run ¹⁴C, featuring technology that is prohibitively expensive to use, compared to working with ¹³C.

How does the MICADAS instrument alter that dynamic?

Raymond: The technology for working with ¹⁴C has changed dramatically. A miniaturized ¹⁴C AMS was developed in Switzerland that greatly decreases the person-power needed to run it, while also decreasing its consumable use and allowing for the direct injection of CO₂, without the need to convert it to graphite — which was time consuming and expensive. These improvements have revolutionized ¹⁴C capabilities and will lead to a nationwide increase in capacity of ¹⁴C research over the next decade.

We argue that these capabilities and capacity need to immediately be fostered in the community of scientists pivoting to NCS research. We propose to make Yale’s MICADAS available to NCS projects, while offering training and community building for a new group of scientists hoping to understand the efficacy and veracity of using ecosystems to capture carbon.

Can you speculate on the impact a larger community of scientists working with ¹⁴C might have on the climate crisis?

Raymond: Despite a general consensus that NCS is a necessary component of effective climate mitigation and the fact that NCS projects are already being deployed — unlike technological solutions to carbon drawdown — the implementation of NCS is lagging. There are political, economic, social, and scientific barriers. A bigger scientific working group will not solve political and social challenges directly but overcoming some of the scientific barriers to understanding carbon dioxide removal will facilitate stronger political and societal action.

Can you give an example?

Raymond: Improved agricultural management for soil carbon sequestration is a good example. It is seen as a critical NCS pathway in the U.S. and elsewhere. However, monitoring and verifying that soil carbon is accumulating is difficult because the rate of change is slow and is superimposed on a large and variable background stock of carbon.

¹⁴C can be used here and in other ecosystems such as “blue carbon” ecosystems [carbon stored in coastal and marine systems] to help constrain carbon uptake rates and measure the impact of ecosystem management on carbon uptake.

What does the instrument look like? When will Yale researchers begin using MICADAS?

Erkkila: It’s impressive. The main machine is 10-and-a-half feet by eight-and-a-half feet, with a main magnet that weighs 1,400 kilograms [3,086 pounds]. There were 13 crates of material brought in for the installation, which was completed on December 12.

We’re testing the instrument now by analyzing samples and soon we’ll make training available for the Yale community. We expect there will be a wide range of interest from researchers at the Yale School of the Environment, in chemistry, Earth and planetary sciences, anthropology, and other parts of campus.