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Old 22nd August 2019, 08:27 AM   #41
lomiller
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Originally Posted by GlennB View Post
Would it have a knock-on effect that makes the atmosphere or general climate impossible for land animals? I'm not disputing what you're saying, but a quick read about mass extinctions doesn't explain why large mammals might be wiped out unless they depend directly on the sea (polar bears, walruses etc spring to mind)
The mass die-off it triggers in the oceans causes changes in ocean chemistry which in tern makes major changes in the composition of the atmosphere. The full scope of changes of these isn’t all that well documented, but two of them would be that Oxygen levels plummet and CO2 levels skyrocket causing even more warming. Other changes are possible as organisms that live in low oxygen conditions often produce toxic by-products.

https://www.pnas.org/content/116/30/14813
https://science.sciencemag.org/conte.../6419/eaat1327
https://science.sciencemag.org/content/348/6231/229
https://www.pnas.org/content/115/26/6596


Originally Posted by Pixel42 View Post
The temperature of the oceans will rise as the world warms and warm water can't dissolve as much CO2 as cold, so surely there's a limit to ocean acidification?
On geological time scales atmospheric CO2 is controlled by the rate at which carbonate rock forms in the oceans. Higher acidity slows down and potentially even reveres this process so rocks are being dissolved instead of formed.

Again, it’s not fully understood but all the major mass extinctions seem to follow the same pattern. Something causes atmospheric CO2 to increase, the oceans acidify, temperatures go way up, Oxygen levels plummet and almost everything dies.
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