## Tag Archives: forcing

Update: see further discussion here NOAA has a webpage on radiative forcing here, which includes a list of equations relating GHG concentrations to radiative forcing, substantially identical to the expressions in TAR. Below is a figure showing, on the left, the graphic at NOAA illustrating their calculation and, on the right, my emulation of this […]

### Hansen Scenarios A and B – Revised

This is a somewhat restated version of an earlier post seeking to understand the differences between Hansen Scenarios A and B. Rather than trying to clarify matters here, Gavin Schmidt posted over at Tim Lambert’s. In this morning’s post, I correctly identified that the difference between Scenarios A and B for periods up to the […]

### Hansen GHG Concentration Projections

In the various disputes over Hansen et al 1988, Roger Pielke Jr and NASA apologist Eli Rabett (who has been said to be occasional NASA contractor Josh Halpern) have each attempted to disentangle the forcing projections implied by Hansen et al 1988 – Pielke here and Rabett here for CO2 and here for other gases. […]

### More on Functional Forms: Wigley 1987

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 […]

### IPCC and Radiative Forcing #2: 1992 and 1994.

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 […]

### IPCC on Radiative Forcing #1: AR1(1990)

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 […]