Over the last week or so, I’ve reported on my efforts to locate the provenance of the functional forms for the relationship between levels of CO2 and other greenhouse gases and temperature. Lubo has also chipped in on the topic from a different perspective proposing a derivation of a log formula from first principles. We’ve […]
Reader DAV raised the following interesting question: The strange thing about 6..3.5 Simplified Equations that gets me is why should CO2, CH4 and N2O have different equational forms? And what would be the physical basis for raising something to the 0.75 or 1.52 power? The whole thing looks ad hoc as if someone was insistently […]
Yesterday I collated IPCC AR3 and AR4 “expositions” of the enhanced greenhouse effect, observing that, in my opinion, they were so baby food as to be essentially useless to a scientist from another discipline. Today I’m going to drill a little deeper in the expositions, going to a 1995 journal comment by Houghton and to […]
One of the fundamental questions for someone interested in the impact of doubled CO2 is exactly how (1) the greenhouse effect works; and (2) how the “enhanced” greenhouse effect works. AR4 FAQ 3.1 poses the question: I’m going to show their answer to this question in full because the answer does not rise about a […]
Chapter 1 of AR4 has some surprisingly interesting comments about models that, to the extent that the points are disclosed in the body chapters, are disclosed so opaquely that they would be undecipherable to anyone other than a few. Here are some interesting comments about flux adjustment – an issue that must surely raise civilian […]
In our summary of IPCC AR1 (1990) on radiative forcing, I noted that the logarithmic relationship and 4 wm-2 values were attributed to: Hansen et al (1988), which in turn cited Lacis et al 1981; and Wigley (1987) which is not presently available to me (or to Wigley himself) and appears not to have been […]
AR4 (chapter 1 on the History of Climate Science) contains the remarkable statement: The strong effect of cloud processes on climate model sensitivities to greenhouse gases was emphasized further through a now-classic set of General Circulation Model (GCM) experiments, carried out by Senior and Mitchell (1993). They produced global average surface temperature changes (due to […]
As an innocent bystander to the climate debates a couple of years ago, I presumed that IPCC would provide a clear exposition of how doubled CO2 actually leads to 2.5-3 deg C. The exposition might involve considerable detail on infra-red radiation since that’s relevant to the problem, but I presumed that they would provide a […]
I’ve been seeking an engineering-quality exposition of how 2.5 deg C is derived from doubled CO2 for some time. I posted up Gerry North’s suggestion here , which was an interesting article but hardly a solution to the question. I’ve noted that Ramanathan and the Charney Report in the 1970s discuss the topic, but these […]
Roy Spencer has an interesting post on cloud feedback at Pielke Sr (which doesn’t permit comments.) He observes: On August 8, 2007, I posted here a guest blog entry on the possibility that our observational estimates of feedbacks might be biased in the positive direction. Danny Braswell and I built a simple time-dependent energy balance […]
Climate Audit 