2011-07-07 08:48:12 | How is the log equation for CO2 forcing derived? | |

John Cook john@skepticalscience... 121.222.9.229 |
Anyone help with this one?
I'm guessing it's calculated from the line-by-line calculations in those papers that theoretically calculate the radiative forcing from CO2 but am hoping someone just lob in an answer before I have to go digging through papers. | |

2011-07-07 08:49:59 | ||

dana1981 Dana Nuccitelli dana1981@yahoo... 64.129.227.4 |
Discussed here. More details are available in the link to Myhre 1998. | |

2011-07-07 09:15:25 | Myre at al | |

Glenn Tamblyn glenn@thefoodgallery.com... 124.180.48.112 |
Myre et al 1998 use several different models, a Line-by-Line model, a Narrow Band Model and a Broad Band Model. The result, 5.35 is actually a best fit to the calculated curves. As Riccardo pointed out in another context, 5.35 only applies between 300-1000 ppm. He used Modtran to look at a much larger range up to 1000's of ppm and it gave 4.8 So although the reationship is logarithmic, it isn't derived from first principles. Rather you do the number crunching in the RT models and curve fit. | |

2011-07-07 10:18:05 | Thanks guys, saved me some running around | |

John Cook john@skepticalscience... 121.222.9.229 |
This whole suggestion box forum is proving quite useful! | |

2011-07-08 06:58:20 | Glenn or Riccardo... | |

Alex C coultera@umich... 67.149.101.148 |
Can either of you give a link to where Riccardo discussed this? I'm pretty interested in that result, and I'd like something I could reference. |