News Climate

Eocene temperature spike caused by half as much CO2 as once thought

Return to a hothouse climate may take less carbon dioxide than expected

Colorado’s Green River Formation

IN THE HOTHOUSE  Lab experiments and crystals found in Colorado’s Green River Formation, shown, suggest that hot temperatures around 50 million years ago resulted from lower carbon dioxide levels in the atmosphere than previously thought.   

USGS

By Thomas Sumner

The hottest time since dinosaurs roamed the planet was caused by nearly half as much carbon dioxide in the air as previously thought, crystals from Earth’s past suggest.