If you think things are bad, listen to a group of climate scientists talk about geoengineering—literally hacking the planet. I had the pleasure of attending the Asimolar geoengineering conference last March and, while there, had the distinct pleasure of spending some time with Steve Schneider.

Even among a group of some of the world’s most distinguished climate scientists, he tended to stand a notch above the rest.

Steve passed away a year ago. Andy Revkin remembers him as one of the most eloquent defenders of climate science.

Watch him take on a room full of 50 self-described Australian “sceptics.” 45 minutes well spent—for them and for the rest of us.