3 ms·
The planet goes through natural carbon cycles. For example, natural orbital variations cause a little initial heating, then feedback effects like permafrost mel
by DennisP 8y ago
The planet goes through natural carbon cycles. For example, natural orbital variations cause a little initial heating, then feedback effects like permafrost melt kick in, taking the planet several degrees further.
Then, over millions of years, the carbon gets absorbed again. Rock weathering removes CO2, and layer after layer of plant material gets sequestered in the ground.
The warming events cause mass extinctions. Hardly anything lives at mid-latitudes, and crocodiles swim at the poles.
There's a lot of geological evidence for all this, and it's the reason people are so worried. If negative feedbacks were quick then we'd see a stable climate in the geological record. We see the opposite. It doesn't take much of an initial shove to tip things into catastrophe, and millions of years to get back to a climate like our own.
- Balgair 8y agoPBS's Eons Youtube Channel has great videos on this topic. Really, all their videos are amazing and very binge-able. Four that may be most relevant are: The Last Time the Globe Warmed: https://www.youtube.com/watch?v=ldLBoErAhz4 https://www.youtube.com/watch?v=ldLBoErAhz4 When the Earth Was Purple: https://www.youtube.com/watch?v=IIA-k_bBcL0 https://www.youtube.com/watch?v=IIA-k_bBcL0 That Time it Rained for Two Million Years: https://www.youtube.com/watch?v=_1LdMWlNYS4 https://www.youtube.com/watch?v=_1LdMWlNYS4 From the Cambrian Explosion to the Great Dying: https://www.youtube.com/watch?v=RDQa0okkpf0 https://www.youtube.com/watch?v=RDQa0okkpf0 The few things that we learn from paleontology is the Earth is Dynamic and that any one creature's life is fragile.