Stephen Schneider, the outspoken Stanford climatologist who has been on the front lines of the battle to address global warming for his entire career, died earlier today. Schneider was on his way from a meeting in Stockholm to London when he died of an apparent heart attack. He was 65.

Schneider was an energetic scientist who rose to the top of his own field and became a leading scientific voice in the debate on global warming. He was founder and editor of the journal Climatic Change as well as a key player in the Intergovernmental Panel on Climate Change. In 2003, Schneider and his wife, Stanford biologist Terry Root, won the National Wildlife Federation’s National Conservation Achievement Award.

Throughout his career, Schneider skillfully wielded a mixture of scientific data, humour and caustic wit to make his points, whether talking to the media, lawmakers on Capitol Hill or addressing his own vocal critics. Schneider recently appeared in Nature’s pages as part of a discussion about how to respond to a reinvigorated community of global warming skeptics. Not one to sit on the sidelines, he called for active engagement. Most recently, he was behind a paper suggesting that scientists who believe in global warming have stronger climate-science credentials than those who don’t.

Last year he recapped more than three decades of climate science and policy with an entertaining book titled “”https://stephenschneider.stanford.edu/SAACS/saacs_book.htm">Science as a Contact Sport: Inside the Battle to Save Earth’s Climate“. He used the same skills, energy and attitude to fight a rare form of leukemia in recent years, helping craft ”https://www.nytimes.com/2005/05/03/science/earth/03conv.html">a new treatment regimen that that not only kept him alive but became the basis of another book titled “”https://www.patientfromhell.org/“>The Patient from Hell”.

In the case of both climate and leukemia, it was a matter of making decisions with incomplete information in an effort to improve the odds of a better and longer future. Indeed, Schneider was an avid believer in risk analysis and used plain language – as well as his own personal experience – to illustrate why it makes more sense to act now in the face of doubt than wait for the dreaded confirmation that we should have acted long ago.