Andrew Babin tries to collect vehicles for business trips. Along with the travel essentials, however, he also brings a roll of electrical tape, duct tape, lab tape, zip ties, and some bungee cords.
“That’s my MacGyver kit: You never know when you’ll need to fix something on the farm or fix a broken bag,” says Babin.
Babin’s trips are far out at sea, on month-long cruises where he works sampling waters off the Pacific coast and in the open ocean. In remote locations, basic repair supplies often come in handy, like when Bobin had to zip tie a key to a sampler to submerge in an icy Antarctic lake.
Babin is an oceanographer and marine biogeochemist who studies marine microbes and how they control the nitrogen cycle between the ocean and the atmosphere. This exchange helps maintain healthy ocean ecosystems and supports the ocean’s ability to store carbon.
By combining measurements he makes in the ocean with experiments in his MIT lab, Babin is working to understand the connection between microbes and ocean nitrogen, which in turn could help scientists identify ways to keep the ocean healthy and productive. His work has taken him to many coastal and open ocean areas around the world.
“You really become an oceanographer and an Earth scientist to see the world,” says Babin, who recently received the Cecil and Ida Green Career Development Professorship in MIT’s Department of Earth, Atmospheric, and Planetary Sciences. We embrace the diversity of places and cultures on this planet. “It’s special to see a small part of it.”
Strong cycle
The ocean has been a constant presence for Babin since she was a child. Her family hails from Monmouth County, New Jersey, where she and her twin sister grew up along the Jersey Shore. When they were teenagers, their parents would take the children on family vacations.
“I’ve always loved being on the water,” he says. My favorite parts of each of these cruises were the days at sea, when you were in the middle of an ocean basin with water all around you.
Babin was interested in science, especially chemistry, in school. After high school, he attended Columbia University, where it became a reality thanks to a visit to the school’s Department of Geosciences and Environmental Engineering.
“For me, the excitement of water and chemistry and the sound of music was always, ‘Oh wow, it doesn’t have to be one or the other,’” Babin says.
He chose to major in geotechnical and environmental engineering, with a focus on water resources and climate hazards. After graduating in 2008, Babin returned to his home state, where he attended Princeton University and pursued a doctorate in earth sciences, with a focus on chemical oceanography and environmental microbiology. His advisor, oceanographer Bess Ward, accepted Babin as a member of her research group and invited him on several-month cruises to various regions of the eastern tropical Pacific.
“I still remember that first trip,” Babin recalls. “It was a tornado.” Others had gone out to sea a thousand times, loading and tying up the boat, and I had no idea. And within a few hours I was conducting an experiment where the boat was rocking back and forth!”
Babin learned to deploy sampling canisters on the sea surface, then pull them out and analyze the seawater for signs of nitrogen—an essential nutrient for all life on Earth.
As is well known, plants and animals that depend on nitrogen for survival are unable to absorb it from the atmosphere. They need an intermediary in the form of microbes that “fix” nitrogen, converting it from gaseous nitrogen into more digestible forms. In the ocean, this nitrogen fixation is carried out by highly specialized microbial species that work to make nitrogen available to phytoplankton – microscopic, plant-like organisms that are the base of the marine food chain. Phytoplankton are also the main way the oceans absorb carbon dioxide from the atmosphere.
Microorganisms can also, under certain conditions, utilize these bioavailable forms of nitrogen for energy and return nitrogen to the atmosphere. These microbes can also release a byproduct, nitrous oxide, a potent greenhouse gas that can also catalyze the loss of ozone in the stratosphere.
Through his graduate work at sea and in the lab, Babin became fascinated with the nitrogen cycle and the role that nitrogen-fixing microbes play in supporting ocean ecosystems and the climate in general. Balancing nitrogen input and output sustains phytoplankton and preserves the ocean’s ability to absorb carbon dioxide.
“Some of the really pressing questions in ocean biogeochemistry have to do with the nitrogen cycle,” Babin says. Understanding the ways this one element cycles through the ocean and how it is critical to ecosystem health and the planet’s climate has been truly powerful.
In the laboratory and out at sea
After completing his doctorate in 2014, Babin joined MIT as a postdoctoral fellow in the Department of Civil and Environmental Engineering.
“My first feeling when I came here was, wow, this is really a playground for nerds,” Babin says. “I embraced being part of a culture where we’re trying to better understand the world while also doing the things we really want to do.”
In 2017, he accepted a faculty position in the Department of Earth, Atmospheric, and Planetary Sciences at MIT. He decorated his lab space in his favorite bright orange color on the top floor of a green building.
His group uses 3D printers to build microfluidic devices that replicate ocean conditions and study microbial metabolism and its impact on ocean chemistry. In this context, Babin has led research expeditions to the Galapagos Islands and parts of the eastern Pacific Ocean, where he has collected and analyzed air and water samples for signs of nitrogen transformations and microbial activity. His new measuring station in the Galapagos Islands is able to infer nitrous oxide emissions over a wide area of the eastern tropical ocean. His group has also traveled to southern Cuba, where scientists have studied microbial interactions on coral reefs.
Babin recently traveled to Antarctica, where he set up camp near frozen lakes and piped in samples of pristine ice water to analyze for genetic remains of ancient microbes. The preserved bacterial DNA could help scientists understand how microbes evolved and influenced Earth’s climate over billions of years.
“Microbes are the builders of the Earth,” Babin emphasizes. “They have been around since life evolved more than 3 billion years ago. We need to think about how they shape the natural world and how they will respond to the Anthropocene, when apes take over our planet.”
Collective action
Babin is now charting new directions for research. In addition to his work at sea and in the lab, he is also involved in engineering, with a new project to design denitrification capsules. While nitrogen is an essential nutrient for maintaining marine ecosystems, too much nitrogen, such as from fertilizers discharged into lakes and rivers, can cause toxic algae blooms. Babin is trying to design environmentally friendly capsules that will remove excess man-made nitrogen from local waterways.
He also began the process of designing a new sensor to measure low oxygen concentrations in the ocean. As the planet warms, the oceans are losing oxygen, creating “dead zones” where fish cannot survive. While others, including Babbin, have attempted to map these oxygen minimum zones, or OMZs, they have done so sporadically, dropping sensors into the ocean at limited ranges, depths, and times. The drumstick sensors could potentially provide a more complete map of the OMZ because they would be deployed on long-range, deep-diving, and naturally self-propelled vehicles: sharks.
We want to measure oxygen. Sharks need oxygen. If you look where sharks don’t go, you might find where there’s no oxygen, says Babin, who is working with marine biologists on ways to tag sharks with oxygen sensors. Some of these big marine fish move up and down in the water column regularly, so you can plot the depth to which they dive and infer something about their behavior. And my suggestion is that you could also infer something about the chemistry of the oceans.
When thinking about what stimulates new ideas and research directions, Babin values collaboration with others, within his group and across MIT.
“My best ideas come from this joint event,” Babin says. “Primarily because we each have different upbringings and look at things from different perspectives.”
He has brought that collaborative spirit to his new role as mission director of the MIT Climate Project. Along with Jesse Kroll, a professor of civil and environmental engineering and chemical engineering, Babin leads one of the project’s six missions: restoring the atmosphere, protecting the land, and protecting the oceans. Babin and Kroll are planning a series of workshops across the university that they hope will create new connections and generate new ideas, particularly on methods for evaluating the effectiveness of different climate mitigation strategies and better assessing the impacts of climate on society.
“One of the areas we want to promote is thinking about climate science and climate interventions as two sides of the same coin,” Babin says. “There are a lot of initiatives that are trying to catalyze that. But we want to make it the best practice. Because we really have the opportunity to do that. Time is of the essence.”
