Copying ancient climate change - a warning from the geological record.

Rocks around 56 million years ago contain evidence of an event called the PETM.

There is a sudden spike in the temperature graph at that time.










The PETM event caused major climate changes.

The ecosystems took 100,000 years to recover.
One possible mechanism for the PETM was volcanic activity next to natural gas and oil fields.
If molten magma broke into the oil and gas, and burned it to make CO2, this would have some parallels to our current situation.
BUT humans have not just burned some oil and gas. 
They have burned just about every bit they can find - plus a lot of coal.
So our CO2 graph is more extreme.

This is a rare and probably irreversible process.
Irreversible, that is, within a human timescale.

 Events like the PETM are sometimes called 'hyperthermal events'.

 Humans appear to be creating the conditions for a new hyperthermal event.



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