And I wanted to add that a key factor for both angstrom and koch low - balling the importance of C02 concentration was not just that they didn't fully envision conditions where energy radiates away, but that they weren't modeling positive water vapor feedback (the magnitude of which but not the existence is still being hashed out). (realclimate.org)
WebHubTelescope: Positive water vapor feedback is known to contribute largely to the +33 C warming that prevents the earth from a 255K average temperature. (realclimate.org)
Indeed, numerous recent studies using empirical observational data have confirmed the positive water vapor feedback. (skepticalscience.com)