Fixing the ozone layer was a technically tractable problem.

The climate change and carbon capture don’t have any workable at-scale solution. And until we can find a massive energy source that’s not fossil fuels we have no theoretical method of capturing the amount of carbon necessary on a meaningful time scale. This is because of the basic physics, like it’s a law of nature we can’t avoid that limits us technologically.

When the original fossil fuels were burned, you had a high quality energy material that was really in a concentrated form. When the fuel was used it released heat and energy and the resulting emissions were released into the atmosphere where it diffused down to a trace concentration level of ~400 parts per million.

So setting aside the technology needed to do carbon capture, we can basically do a napkin sketch of the scale of energy needed. Basically, there are three main costs to the project.

• you need to capture the carbon. This will be a thermodynamic cost that’s around as much energy as was released from the fossil fuels in the first place (just running backwards)
• you need to take the entire earths atmosphere and filter out the carbon from everything else. There is an absolute theoretical minimum energy needed to handle this amount of CO2 and concentrate it that’s probably 200kw/h per ton if you use machines for direct air capture (not growing plants etc). With the current CCS tech that we have developed, it literally costs more energy to run this one step than what the original fossil fuels released
• by now you have tons and tons of carbon and it has to be stored somewhere which would be a physical feat with a scale that’s on par to the combined industrial activities of the current civilization. Massive mines, drilling and digging deep into the ground, giant containers moving around, pipelines being built etc

The exact numbers don’t exactly matter but this is a way bigger way more industrial and way more energy intensive process than everything humans have ever done in history all put together.

Oh yeah… One other pesky detail:

• we need to do this super fast also. Many things that could happen slowly over centuries are easy. But doing this in a decade or two is very very complicated and has huge power costs

So what happens in this area is that people point at a small staircase that goes to the second story of a house and say… “We know how to build stairs, we just need to start doing it if only our leaders and fossil fuel corporations…”

No, you can’t take stairs all the way to SATURN That’s SO FAR BEYOND realistic that there is no point in anyone wasting any time or money or resources on even pretending to try.

So people drop “we have carbon capture technology, we just need to do it” they say this as if the tech that we developed simply existing means everything hard is solved.

Not only is that not the hard thing, the HARD issue makes it seem incredibly unlikely we can do it without discovering an energy source.

If it wasn’t for that pesky thermodynamics.