by K. Richard, Aug 25, 2022 in NoTricksZone
A late 2021 study finds water vapor and temperature changes accounted for 90% of the changes in clear-sky downwelling longwave or greenhouse effect forcing since the mid-1980s. CO2 forcing assumed a mere bit-player role.
The seminal Feldman et al. (2015) study concluded it takes 10 years and a 22 ppm increase in CO2 to account for just one-tenth of the total longwave or greenhouse effect forcing in recent (2000-2010) climate change trends. The remaining longwave forcing contribution is from water vapor and clouds.