Michael McElroy, pioneering atmospheric scientist, dies at 86

Michael B. McElroy, the Gilbert Butler Professor of Environmental Studies in the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and chair of the Harvard-China Project on Energy, Economy, and Environment, died on Jan. 8 at the age of 86.

McElroy was a towering intellectual whose pioneering research shaped how we understand the atmospheric chemistry of more than half the planets in our solar system, including Earth. His groundbreaking work on human-induced stratospheric ozone depletion and climate change shaped the direction of international environmental agreements, notably the Montreal Protocol, and played a vital role in protecting our planet from harmful ultraviolet radiation. Later in his career, McElroy expanded his focus to energy science and decarbonization in the U.S. and countries such as China and India, where his work has influenced energy and climate policy.

At Harvard, McElroy was a driving force behind the University’s commitment to environmental and climate science. At a time when other universities were shuttering geology and Earth science departments, McElroy championed the creation of the Department of Earth and Planetary Sciences and became its founding chair in 1986. He helped establish the Environmental Science and Public Policy concentration in 1993; chaired the first University-wide Committee on the Environment; founded the Harvard-China Project on Energy, Economy, and Environment; and became the first faculty director of the Harvard University Center for the Environment (HUCE). 

McElroy was known for his broad intellectual curiosity, his commitment to collaboration, his dedication to teaching and mentorship, and his serious and tireless drive to find solutions for the hardest problems facing our planet today. 

“When I look back on my career, of course I am proud of the research, teaching, and the opportunity I’ve had to shape young minds,” McElroy said when he was awarded the William Bowie Medal from American Geophysical Union in 2024. “What also stands out are the collaborations I’ve had with colleagues across Harvard, China, and the world, and the enduring connections and friendships I’ve built. Ultimately, we are all in this fight against climate change together.”