Lonnie Thompson

Lonnie Thompson was born on 1 July 1948 in Gassaway, West Virginia, and was raised on a farm there. He studied geology at Marshall University in Huntington, West Virginia, where he met Ellen Mosley, then a physics student. Both went on to graduate study in geology at Ohio State University. He received his MS in 1973 and his PhD in 1976, with a thesis titled Microparticles, ice sheets and climate.

Thompson founded the ice core research programme at Ohio State while still a graduate student, and spent his whole career at the university as a professor of Earth Sciences and a research scientist at the Byrd Polar and Climate Research Center. In the 1970s he was the first scientist to bring back ice samples from a remote tropical ice cap, the Quelccaya Ice Cap in Peru, and analyse them for ancient climate signals.

Over more than four decades he led around 60 drilling expeditions to polar regions and to tropical and subtropical ice fields in 16 countries, among them China, Peru, Russia, Tanzania and Papua in Indonesia. Because helicopters cannot work in the thin air of high mountains, he and his team developed light, solar powered drilling equipment that could be carried up by yaks, mules, horses and people, and they often worked for months at a time above 5,500 metres. The resulting climate records appeared in more than 230 scientific articles.

His measurements of glacier retreat from the 1970s onwards showed that ice around the world was melting and that recent warming lay outside the natural range of climate variability for thousands of years. In 2001 he predicted that the ice fields of Mount Kilimanjaro would disappear within about 20 years. He and his wife served as advisers on the 2006 documentary An Inconvenient Truth, which referred to their work.

Thompson was married to Ellen Mosley-Thompson, herself a paleoclimatologist, for more than 40 years, and the two worked side by side as research partners in the field and the laboratory. They had a daughter, Regina. In May 2012 he underwent a successful heart transplant and returned to research afterwards. His life and work were the subject of the 2023 documentary Canary, directed by Danny O'Malley and Alex Rivest, which won Best Feature at the 2024 Jackson Wild Media Awards.

Ohio State University announced on 3 November 2026 that Lonnie Thompson had died at the age of 78 after a brief illness. The announcement was made by the university and its School of Earth Sciences, and university president Ravi Bellamkonda paid tribute to his 55 years at Ohio State and his role in building the Byrd Polar and Climate Research Center. The exact date of death and the nature of his illness were not made public. The School of Earth Sciences said future opportunities to honour his memory would be shared when available.

Thompson is remembered as the scientist who showed that tropical mountain glaciers hold detailed records of past climate, and as one of the earliest and clearest witnesses to their disappearance. Time magazine named him one of its Heroes of the Environment in 2008, and the Tyler Prize he received in 2005 is often described as the environmental equivalent of a Nobel Prize. Ohio State said it would work with its partners to honour and carry on his legacy.