this post was submitted on 31 Jul 2023
141 points (95.5% liked)
Climate - truthful information about climate, related activism and politics.
4704 readers
452 users here now
Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.
As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades:
How much each change to the atmosphere has warmed the world:
Recommended actions to cut greenhouse gas emissions in the near future:
Anti-science, inactivism, and unsupported conspiracy theories are not ok here.
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Weren't there periods in the past where temperatures were "a few degrees" higher and still had conditions that could sustain human life?
Here is a very good graph demonstrating the first part of the problem:
https://xkcd.com/1732/
The globe is warming faster than any animal can adapt. And it's going to keep warming, even on net zero emissions, because the carbon dioxide is already in the atmosphere.
The second part of the problem is that previous periods of warming did not involve the release of underground carbon reserves. That carbon has been there since the age of the dinosaurs. That carbon is going to CONTINUALLY warm the earth, it's not going to just stop warming up like a volcanic eruption. Not until it's recaptured and buried.
Also, the carbon dioxide is turning into carbonic acid in the oceans, and we haven't felt most of the effects of that because the calcium carbonate buffer has been protecting us. When the buffer runs out, we're going to see some very big changes very quickly.
According to graphs I have seen, this won't be the fastest warming period ever, even by worst predictions. Example: https://scitechdaily.com/images/Past-and-Future-Global-Temperature-Trends-scaled.jpg
The second problem I have with your post is that there were far higher CO2 levels in history which didn't correlate with temperature rises.
Also, a lot of this global extincion theories are just theories that are based on predictions that are dependant on inputs and not all inputs (not even close) are considered in those calculations. Even IPCC itself thinks not including clouds feedback (and it's dominant termostatis control of temperature) could be a potential problem in their predictions.
All in all - human extinction theory is not something there is a consensus for and it certainly is a part of alarmism.
However, scientists have conclusively demonstrated that in the 19th through 21st centuries, CO2 emissions directly predict rises in temperature.