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Snowball Earth
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”??
