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Taking CO2 out of the air would be an absurdly expensive way to fight climate change
(www.theverge.com)
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.
Its Not that hard to understand. Since the industrial revolution we've taken energy out of a system that, as a pollutant, generated CO2.
If you want to remove the excess CO2 we generated we'll have to put back at least the same amount of energy to reverse that process. Adding in typical losses like heat, you can triple or quadruple that.
So let's say we need four time the energy that humanity had generated since the industrial revolution to get co2 back to pre industrial levels. Great. ALL this energy must come from non CO2 sources like solar, wind, nuclear, hydro, because of not you're just spending 100 units of CO2 to capture 30...
This already means that currently, carbon capture is a bad idea. Any energy spent on that is energy that generated more CO2 than it will capture and even if it is renewable, or nuclear, it would be better spent on something else and that something else would still spend 100 units CO2 for the 30 you capture.
So this means that step one, before really starting to capture CO2, is getting ALL of your energy generation where possible (airplanes, for example, cannot go electrical). We're not even at step 0.1, honestly.
We need to get rid of all fossil fuel cars, trucks and power plants before we can even start thinking about fixing this and we're literally a sliver in that direction, currently.
So can we please PLEASE start with this damn conversion already?
There actually is a much easier way with enhanced weathering. Igneous rocks naturally carbonate as they weather, and pull CO2 out of the atmosphere to make carbonates. This is why when you have a mountain building event it causes global cooling. So what you need to do is expose more igneous rock surface area to the atmosphere by grinding it up and spreading it out. This also costs energy but not nearly as much as carbon capture, and it's also slower. But we know it works, and there are several pilot studies trying it.
The problem is capitalism. There's no room for a zero-profit process in the economic system that everyone accepts as necessary. It has to somehow enrich the investor class.
Interesting idea, haven't heard that one yet, but it does sound like something that a) would require literally mountains of energy and b) would take a way WAY long time, much more than we have available.
Also, just blaming it all on capitalism as a blanket excuse is a but too simple, not?
Actually weathering can happen on the timescale of decades; it's all a matter of how much surface area of the rock you expose. Nature does this too slowly. In terms of energy input, grinding rocks gets a huge head start with all of the mine tailings we already have. Here is an example:
https://pubs.acs.org/doi/10.1021/acs.est.3c03609#
In terms of capitalism, for me it's not too simple. Capitalism is a profit driven model that can't comprehend long term ecological damage. It becomes a "negative externality" which can then be modelled by economists however they want (which is why they don't agree about how bad it is). If we had a system based on human well being we would have solved climate change already. It's simply not profitable to replace the fossil fuel economy with renewable energy sources. It requires a level of investment capitalists can't comprehend. This is largely why societal change comes from governments which can simply invent money to throw at a problem (think New Deal or Bidenomics).
The complicated part is answering why humans can't seem to get past capitalism. I think we all agree the system is doomed; we just can't figure out how to get away from it.