The Earth can't simply continue heating up until the oceans boil and the rocks melt because the CO2 level has gone up a bit. That would only be possible in the presence of a very strong positive feedback loop that made the Earth better and better insulated the hotter it got, which would be unlike any other thermal system we know of.
Edit: there are some positive feedback effects, like water vapor being a greenhouse gas, that will likely make the end result hotter than that expected based on the change in CO2 alone, but it will not lead to heating just continuing indefinitely.
I'll be honest, I'm convinced humans have a big hand in climate change, but I can't seem to determine whether I merely need to lobby my rep for green legislation or start taking survival classes for an impending collapse of JIT supply chains and society in general.
Lobby for green legislation. We need to influence politics to finally act in a serious manner. As we accomplished with the ozone hole as mentioned in the article
https://climate.nasa.gov/news/2785/unexpected-future-boost-o...
If human CO2 emissions stopped, atmospheric temperature would still go up for a while (perhaps decades), because of thermal inertia - for instance, the oceans haven't fully warmed to equilibrium, so they currently have a cooling effect on the atmosphere. There could then be some further increase in atmospheric CO2 because warm water holds less CO2 than cold water. There could be other positive and negative feedbacks (eg, higher CO2 and warmer temperatures may increase plant growth, sequestering CO2.)
It's very unlikely that any of these feedbacks are of the "runaway" variety, because if that's how the earth worked, it would have become uninhabitable long ago, since there have been various temperature shocks over the last billion years or so that haven't lead to this fate. (If there were really "runaway" feedbacks, it wouldn't even take a big shock - the tiniest change would be amplified and push the climate into either extreme heat or cold.)
This IS the greenhouse effect. Increased levels of greenhouse gasses result in a warmer planet over time as Earth reflects less solar energy back into space. This warming leads to many known runaway feedback loops: increased wildfires that release more CO2 and destroy natural carbon sinks, reduced albedo from ice melt, increased moisture in the atmosphere, warmer oceans leading to less carbon sequestration by phytoplankton, methane release from ice melts.
There are more. Please read some recent literature to understand this better than anyone can summarize on HN. I recommend The Uninhabitable Earth
> at net zero, the rate will stabilise
should read something like; at net zero [emissions], the temperature will stabilise.
Read this bit:
"""
"""This view that a given CO2 level determines a rate of global heating does not match any scientific view of the greenhouse effect of which I'm aware.