Short answers, pulled from the story.
The Charney Report concluded that there would be appreciable warming due to increased atmospheric carbon dioxide concentrations. It estimated equilibrium climate sensitivity at three degrees Celsius with a margin of error of plus-or-minus one degree.
Philip Handler selected Jule Charney as chair of the working group on carbon dioxide and climate. Charney was a renowned meteorologist and modeler at the Massachusetts Institute of Technology who assembled eight distinguished scientists to form the Ad Hoc Study Group on Carbon Dioxide and Climate.
The group convened on the 23rd of July 1979, in Woods Hole on the Massachusetts coast. They met at a conference center owned by the National Academy of Sciences where nine scientists attended along with their families.
The range of error estimated in the report remains consistent with evaluations found in IPCC Fifth Assessment Reports. The central value aligns closely with findings from the IPCC Sixth Assessment Report published in 2021 which concluded with a narrower range of error than the original study.
Jule Charney decided to evaluate not only the JASON committee's model but also more advanced three-dimensional general circulation models. Syukuro Manabe worked at NOAA's Geophysical Fluid Dynamics Laboratory while James E. Hansen led NASA's Goddard Institute for Space Studies.