New understanding to past global warming events: Hyperthermal events may be triggered by warming A series of global warming events called hyperthermals that occurred more than 50 million years ago had a similar origin to a much larger hyperthermal of the period, the Pelaeocene-Eocene Thermal Maximum (PETM), new research has found. The findings represent a breakthrough in understanding the major "burp" of carbon, equivalent to burning the entire reservoir of fossil fuels on Earth, that ... [News Source]