Snowball Earth

Snow Ball Earth between 750 and 600 million years ago.

2 Billion years ago O2 began forming in the atmosphere

http://www.atmosedu.com/Geol390/articles/RoyeretalCO2GSAToday%2704PhanerozoicClimate.pdf

CO2 has been a driver of Climate for Millions of years. (phanerozoic 550 Mya to present)

There have been large ice sheets during the Phanerozoic ~300 Mya

Our present Ice age began around 2 MYa

Most of the past 200 Myr has been very warm and dominate by a greenhouse Earth. Our present state (the Pliestocene began about 2 Myr ago)

K-T boundary~ 65 Million years ago.

End of Dinosaurs.

Evidence suggests Asteroid impact cause global cooling for several years

Shock patterns in quartz

Chicxulub (Chik-shoo-loob) impact crater Near Cancun, Mx.“tail of the devil”??