The UN says that methane causes “at least a quarter of today’s global warming.”
I ran the RRTM radiative transfer model using their mid-latitude-summer model, and found that removing all CH4 from the atmosphere reduced downwelling longwave radiation at earth’s surface from 348.6012 w/m² to 348.0023 w/m². Methane is responsible for less than 0.2% of the total greenhouse effect.
Greenhouse effect | Definition, Diagram, Causes, & Facts | Britannica
