[sokoloff]

CO2 is the gas everyone talks about. Other gases also contribute (CH4, H2O, N2O, SO2, and others).

[DennisP]

People talk most about CO2 because it has the most total effect as a driver of climate change. CH4 for example has a greater effect per kilogram, but we emit a lot less of it and it doesn't last nearly as long.

H2O technically affects the temperature even more than CO2 but it's not a driver, because the total H2O in the atmosphere depends on overall temperature. Emitting more H2O, from hydrogen cars or something, would just mean you get more rain somewhere.

[blululu]

Yeah because it’s the biggest new contributor. Technically water is the biggest green house gas but there are good reasons for focusing on CO2.

[specialist]

Yes and:

And it's very likely any fixes will not simply be a matter of reducing atmospheric carbon.

Here's a first principles explanation for why carbon net zero and sequestration are not the direct, most expedient path towards reducing temps.

"Dr. Ye Tao on a grand scheme to cool the Earth" https://www.volts.wtf/p/volts-podcast-dr-ye-tao-on-a-grand#d...

TLDR: Given the time and resources we have, focus on strategies for cooling the atmosphere the fastest way possible.

[DennisP]

Maybe most sensible approach: use SRM to reduce temperature directly and head off nasty positive feedbacks like melting permafrost, but treat that as buying time to get CO2 down to a safe level.