Peter Brannen is an award-winning science journalist and contributing writer at The Atlantic. His work has also appeared in The New York Times, The Washington Post, Wired, Aeon, The Boston Globe, Slate and The Guardian among other publications. His book, The Story of CO2 is the Story of Everything, will be published August 26, 2025 by Ecco. His book, The Ends of the World, about the five major mass extinctions in Earth's history, was published in 2017 by Ecco. 

Peter was a 2023 visiting scholar at the Kluge Center at the Library of Congress, and is an affiliate at the Institute of Arctic and Alpine Research at the University of Colorado-Boulder. He was formerly a 2018 Scripps Fellow at CU-Boulder, a 2015 journalist-in-residence at the National Evolutionary Synthesis Center at Duke University, and a 2011 Ocean Science Journalism Fellow at the Woods Hole Oceanographic Institution in Woods Hole, MA. His essays have been featured in the Best American Science and Nature Writing series and in The Climate Book by Greta Thunberg.

Peter is particularly interested in geology, ocean science, deep time, the carbon cycle and the Boston Celtics.

Peter splits time between Cambridge, MA and Damariscotta, ME and is a placental mammal.