Digging Deep with Benjamin Linzmeier
“I miss snow.”
Benjamin Linzmeier, a postdoctoral researcher with the Ubben Program for Climate and Carbon Science at the Institute for Sustainability and Energy at Northwestern (ISEN) in Evanston, Illinois, hurried to his laboratory down a window-lined hallway on a warm and rainy January afternoon.
On the surface, his comment appears reminiscent of his childhood in Wisconsin. However, the words from the geoscientist—who studies extinct organisms and their relationship to climate—run much deeper.
Since joining Northwestern in the fall of 2017, Linzmeier has been documenting changes in the carbon cycle around one time of major environmental disruptions of the distant past, caused by massive volcanic eruptions and asteroid impacts, and how those changes and events shaped life on Earth. “I use chemistry to understand the biology and ecology of extinct organisms and how that relates to climate,” he explained. His hope is that his work will provide unique insights for how the environment might be affected by the current changes taking place in the carbon cycle that are tied to climate change.
Linzmeier’s research extends across a time period spanning nearly 1 million years, from the days of the dinosaurs some 65 million years ago to the world that existed just after the prehistoric creatures vanished. Records from that monumental era can still be found today in the ‘rock record’ of places like Seymour Island in Antarctica, the source of the bivalve shells and other marine fossil samples he evaluates to pinpoint the environmental conditions of the time.
By measuring the ratio of different masses of the atoms of calcium in the shells, which vary in response to ocean acidification, he can evaluate what their environmental conditions were at specific points in their lifetime. “I’m measuring calcium isotopes from right before the dinosaurs went extinct and then across that event,” he explained. As for the source of his fossils, “This is a pretty special place, because it’s a high-latitude area and we know with modern climate change that high-latitude areas are currently changing faster than lower latitude areas in terms of their average annual temperature, and they are more vulnerable to extinction.”
Judging from the prehistoric-sized 4-foot-tall bone casually leaning against the wall in Linzmeier’s office, he would have been happy to work directly with dinosaurs to make sense of their world and the dramatic environmental changes they faced. However, he welcomes the opportunity to tap into the expertise of his faculty mentors in the Department of Earth and Planetary Sciences at Northwestern: Department Chair Matthew Hurtgen, Director of the Environmental Sciences Program Andrew Jacobson, and former Department Chair Brad Sageman. In addition, Linzmeier leverages state-of-the-art technology—frequently working with lab manager Meagan Ankney to use the thermal ionization mass spectrometer (TIMS) to examine the chemical composition of powder created from shells.
“I think one of the potential things that comes out of the data that I’ve produced here is thinking about the causes of mass extinction—that major state change at the end of the Cretaceous Period. There are carbon changes happening early, a couple hundred thousand years before the [Chicxulub asteroid] impact happened, and then again just before the impact happened too,” he said.
Breaking the Mold
Linzmeier is not afraid to push boundaries. He grew up 5 miles outside of a town with a population of just 350 people, and was the first in his family to attend college. He admits the road to academia was not easy, but he is proud to be in a position to bring new information to the world on such a critical scale. His advice for others who wish to follow in his path from a similar background? “I think that there’s a whole lot of the world that you get to know more about if you pursue academia. It opens up doors. And it’s often difficult to push the door open initially but there are plenty of opportunities on the other side.”
Focus on the Future
On a personal level, Linzmeier is enthusiastic about the future. He is eager to bring his knowledge to students and to earn a professorship in the near future. Working across disciplines at Northwestern has both inspired him and encouraged him to press on with his research to find new links and understandings. “I think I’m still enthralled by studying things in deep time because there are opportunities to be the first person to see something, to come up with an idea to explain some type of data,” he remarked.
As for our planet, he sees a future that is different than what we know today. “The thing that I worry about thinking about climate change is modern civilization’s resilience to it. I don’t do work on that particular question, but my intuition is that we are more confident in our resilience than we should be,” he said, noting that historically, the Earth’s health seems to have played a significant role in its ability to respond to atmospheric events. “Thinking about mitigating carbon emissions is not about saving the planet. It’s about preserving humans and our cultures.”