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by adrianN 15 days ago
Optimistic of you to assume it’ll only be fifty years. Do you expect humans to adapt that quickly? The climate will be messed up for centuries at least
1 comments

Where do you get the "centuries at least" bit? The hole in the ozone layer "repaired itself" much faster after humans made changes. There's no more acid rain in Los Angeles after humans made changes. These all happened within my lifetime. We also saw during covid lock downs how quickly things changed from the sudden slow down in human activity.
Changing refrigerants and propellants away from fluorine chemistry and installing desulfurization equipment on coal plants are both many orders of magnitude easier than reducing the amount of hydrocarbons we burn globally to the point where the temperature increasing is stopped or reversed.

One of them requires the entire global population cooperate to burn fewer hydrocarbons. The examples you mentioned were handled in the US by regulating power plant operators and chemical manufacturers.

The point is that if humans would change, the Earth would change quickly. The way the first comment was worded made it sound like the Earth would need that time and not that humans will drag it out that long. That's a given. The Earth will snap back fairly quickly if the pesky humans would just get their shit together.
There are some positive feedbacks that once triggered could not be reverted for millenia. For example a potential stop of the AMOC https://en.wikipedia.org/wiki/Atlantic_meridional_overturnin...
Melting glaciers and ice caps is another such thing. As soon as the polar albedo changes because there is no more snow and ice, temperatures will stay elevated for a far longer time than it took to melt those caps.
You can look up the carbon cycle on Wikipedia, it is fairly well understood where atmospheric carbon can go. Most processes that sequester carbon long term take geological time spans. So unless you think we engineer sequestration at a rate comparable to what we emit today, atmospheric carbon is here to stay for a really long time. Personally I think we won’t be able to scale sequestration technology sufficiently in the next decades to make a dent in the carbon levels.
Carbon sequestration through plant-life seems to increase more than expected with rising atmospheric CO_2 levels. We are currently seeing increased global plant mass.
Both of those problems you cited are far smaller and easier to fix than the ~1,500 gigatons of C02 humans have emitted in the past century. CFC's have a half life of only 50 years, C02 just persists now forever since we're dumping it faster than can be consumed. Acid rain was a mostly localized problem, not one spanning the entire Earth and affecting ocean temps, ocean currents, etc etc. The cited problems are insanely easy to solve compared to global climate change.

It's likely / probably unsolvable at this point as we're hitting tipping points for which there is no effective return such as permafrost melting and releasing more co2, causing more heating, melting more co2, etc and partial shutdowns of critical ocean currents. But yeah I know...MUH FREEDOM.