I really doubt the “science” behind this. We haven’t done sh**.
I believe it’s down to conversion from coal to natural gas mostly.
Sure we have. We've been replacing coal-fired plants with natural-gas fired plants at a high rate. MASSIVE reductions in CO2 result. All thanks to directional drilling and fracking making the US the number-one producer of natural gas in the world.
As others have noted, that’s the natural consequence of replacing coal with methane as a carbon-based fuel. And that was probably done as much based on economic considerations (we’re rolling in natural gas) as environmental ones (despite continual efforts to make coal fuel non grata).
When you burn coal, almost all the energy comes from breaking carbon-carbon bonds and replacing them with stronger carbon oxygen bonds - each of those transformations leads to the formation of a CO2.
When you burn methane, most of the energy comes from replacing carbon-hydrogen bonds with oxygen-hydrogen bonds (of water); you also convert carbon-hydrogen bonds to the carbon-oxygen bonds of CO2, but the fraction of energy coming from CO2 is much less with the methane of natural gas.
I’m not of the belief that our reduction of CO2 emissions makes a damn bit of difference in the global climate, but if combusting methane leads to less CO2 than combusting coal, and it’s more economical, that’s fine by me.
Now we just need to find somebody who can explain the science to Greta, AlGore and all their little friends.