AGU mourns the passing of Michael McElroy, distinguished planetary and atmospheric scientist

It is with deep sadness that we share the passing of Dr. Michael McElroy, who died last month at the age of 86. 

Dr. McElroy was a towering figure in the Earth and space sciences—a brilliant atmospheric scientist whose contributions fundamentally shaped our understanding of planetary atmospheres, climate science, and environmental policy. His career spanned more than six decades of transformative work, from pioneering research on the atmospheres of Mars and Venus to groundbreaking investigations of Earth’s ozone depletion and climate change. 

The AGU community had the privilege of recognizing Dr. McElroy’s exceptional contributions on multiple occasions. He was honored with the James B. Macelwane Medal in 1968, named a Union Fellow in 1971, and most recently, in 2024, he was awarded our highest honor—the William Bowie Medal. In his Bowie Medal citation, James E. Hansen eloquently described Dr. McElroy as “a rare combination of scientist, scholar, educator and visionary leader in science and its applications to human welfare and the natural world.” 

Dr. McElroy’s impact extended far beyond his research. As the Gilbert Butler Professor of Environmental Studies at Harvard University and chair of the Harvard-China Project on Energy, Economy and Environment, he mentored generations of scientists, championed diversity and inclusion, and fostered international collaboration. His work directly influenced the Montreal Protocol and shaped critical environmental policies worldwide. Vice President Al Gore, with whom he collaborated on climate policy, called him “a brilliant, path-breaking scientist, a true leader in the scientific community, a highly valued colleague, and a dear friend.” 

The scientific community has lost a titan, but his legacy—in the policies he helped shape, the students he mentored, and the collaborative spirit he embodied—will endure for generations to come.