5 Questions With a Scientist and Student Researching Carbon Storage
Climate science was not on Grace Brown’s mind when she decided to attend Barnard. Brown, who grew up in Westfield, New Jersey, had always gravitated toward outdoor conservation activities. When she came to Barnard, she was considering majoring in political science. But her environmental studies courses and Barnard’s access to cutting-edge science at the Columbia Climate School drew Brown into a new area of exploration.
Last spring, Brown, who is now a senior and an environmental studies major, was looking for a project for her senior thesis. She asked for suggestions from environmental sciences professor Martin Stute, a leader in the area of hydrology and groundwater studies. As an adjunct senior research scientist at the Climate School’s Lamont-Doherty Earth Observatory, Stute has also been advancing a pivotal climate science research and development area: carbon capture and storage.
Stute needed help with an ongoing, high-profile project in Oman. Brown would only need to go as far as Palisades, New York, and Columbia’s Lamont-Doherty Earth Observatory to be part of groundbreaking science. Once an elusive goal, carbon dioxide removal — using science to remove CO2 from the air and then stow it safely away — is now considered an important, emerging technology, critical for helping reduce greenhouse gas emissions and, in this way, is helping to solve the greater climate change crisis.
In the Q&A below, Stute and Brown talk about the Oman project and the promise of carbon capture.
What’s involved with carbon capture and sequestration?
MS: In order to limit the effects of climate change, we need to not only cut back on our greenhouse gas emissions (mostly CO2 and methane) but also take some of these gases that we have put into the atmosphere back out. Carbon (in the form of CO2 and methane) can be captured at the source — for example, at a powerplant — or directly from the air and then stored in plants, industrial materials, or in subsurface pores and cavities. I am working on one of the safest ways to store CO2 in the subsurface using a process called ‘carbon mineralization,’ in which CO2 is dissolved in water, pumped into reactive rocks such as basalts, where the CO2 is then converted to solid carbonate minerals (similar to limestone). I was part of an international team that demonstrated this process in a field application in Iceland.
What’s happening in Oman?
MS: This project is part of a large international research program that explores the geochemistry and microbiology of an ancient uplifted seafloor in the desert of Oman. Besides being used to study basic biogeochemical processes, this formation could also store vast quantities of CO2, similar to the basalts in Iceland. A key question of the study is how fast water circulates in this formation. Our study — funded by the US National Science Foundation in collaboration with California State University, Sacramento, and the Oman Drilling Project — uses substances naturally occurring in groundwater at very low concentrations (so-called ‘tracers’ such as radiocarbon, tritium, and noble gases) to determine how long the water has been underground and how fast it moves. This information is crucial for determining chemical reaction rates and how this formation could be used for CO2 storage.
How far are we from realizing the goal of removing carbon dioxide from the air and storing it away safely?
MS: The capture and storage of large CO2 sources are well understood and economically feasible. Free-air capture is still expensive; large-scale demonstrations must be developed and deployed. However, many commercial carbon capture and storage plants are now operating worldwide. In fact, a startup company called 44.01, which received last year’s Earthshot Prize, has begun experimental CO2 injections in Oman. All this is not to say that carbon capture and storage is the silver bullet that will solve our greenhouse gas problem. It is just one approach that needs to be taken if we want to limit the worst effects of climate change. We still need to move to renewable energy sources as quickly as possible and transition to a sustainable economy.
What surprised you most about the Oman project and your work in support of it?
GB: I was surprised by the amount of technical, hands-on work I’ve gotten in methods development and instrumentation. Last summer, we spent a lot of time in the lab modifying our different analytical instruments to enable us to develop techniques specific to measuring samples and collecting data for the project. While this kind of method development is a large part of the research process, I was surprised to get this kind of behind-the-scenes look at the more technical aspects of scientific instrumentation. Something else that surprised me, I hadn’t realized how students can get involved with and contribute directly to groundbreaking projects. I’ve found that through the senior thesis and other opportunities available to us, students are really able to make an impact and contribute to extremely relevant research. It’s been very exciting and rewarding.
Does being so involved with emerging research make you more hopeful about the future in light of what we know about the threat of climate change?GB: Being involved with emerging research definitely makes me more hopeful about the future. I think a major factor contributing to pessimism about climate change is the feeling that there’s nothing we can do about it, so I feel much more optimistic when I can take action. Spending time at places like the Lamont-Doherty Earth Observatory, I can’t help but feel hopeful when surrounded by so many scientists at the top of their field working very hard to understand the Earth and its changing climate better.