Dead Dinosaurs and Nuclear Wars-the Climate Science of Black Carbon in the Stratosphere

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Prof. Brian Toon
Dept. of Atmospheric and Oceanic Sciences
University of Colorado, Boulder
Monday February 22, 2021, 2 PM EST


Sixty six million years ago a mountain sized chunk of rock, traveling at more than 10 times the muzzle velocity of an assault rifle, slammed into the shallow sea covering what is now the Yucatan Peninsula of Mexico. Shortly thereafter the 5th of the Earth’s great mass extinctions occurred. Many of the same phenomena that killed the dinosaurs may occur if there is a nuclear war. Here I describe how the dinosaurs died, and the possible consequences of small and large nuclear wars. I will also mention work on recent large fires in Canada and Australia that inform us about large smoke injections into the stratosphere. Unfortunately, at present, we are not capable of stopping an asteroid from hitting the planet. It remains to be seen if we can prevent a nuclear conflict.


Brian Toon was founding Chair of the Department of Atmospheric and Oceanic Sciences at the University of Colorado. He has published over 350 peer reviewed papers on atmospheric and planetary science. He received the AMS Rossby Research Medal, the AGU Roger Revelle Medal, and was recognized by UNEP for contributing to the 2007 Nobel Peace prize awarded to the UN and Al Gore. He has been a leader of 10 NASA aircraft field missions studying the ozone hole, clouds, and air pollution. He has studied aerosols and clouds in every part of Earth’s atmosphere, almost every solar system planet and beyond.


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Feb 22 2021


John Xun Yang