Paul J. Crutzen

Paul Jozef Crutzen was a Dutch meteorologist and atmospheric chemist who built his career studying what happens in the sky. In 1995, he shared the Nobel Prize in Chemistry with Mario Molina and Frank Sherwood Rowland for work on atmospheric chemistry, particularly the formation and decomposition of ozone. Beyond the ozone layer, he turned his attention to climate and catastrophe: he was among the first scientists to model nuclear winter, the potential climatic collapse from large-scale atmospheric pollution - smoke from forest fires, industrial exhausts, oil fires. Later he gave a name to the present: the Anthropocene, a proposed new epoch in the Quaternary period defined by human actions reshaping the Earth. He was a member of the Royal Swedish Academy of Sciences and an elected foreign member of the Royal Society. He died on 28 January 2021.