Someone asked Bill Kininmonth:
If AGW is a fiction, is it not a useful fiction?
He answered with a resounding NO!
“Firstly, the AGW debate (now proselytisation) is diverting attention from those real issues that you mention and causing public and private investment in a range of actions that will have no present or future benefit. How often does it need to be said that CO2 is a colourless, odourless gas whose only detrimental characteristic is to form a very weak acid (carbonic acid) when dissolved in water. On the other hand, CO2 is an essential component of photosynthesis – increased CO2 in the atmosphere is an effective fertiliser of the biosphere as shown by horticulturalists artificially increasing the CO2 content within glasshouses. CO2 is NOT a pollutant.
There is every reason to believe that increasing CO2 in the atmosphere will have no significant impact on the climate system. The greatest impact of atmospheric CO2 on the earth’s radiation budget was the first 20 ppmv. After this concentration the source of IR radiation to space from the active CO2 radiation bands was in the stratosphere, where temperature does not change as the emanation goes to higher and higher altitudes with increasing concentration.
There is every reason to believe that earth is near an upper temperature limit given its present distribution of land and ocean and the strength of solar irradiance. The earth’s surface is heated by way of solar radiation and back IR radiation emanating from clouds, greenhouse gases and aerosols; it is cooled by conduction, evaporation and IR emission. Solar radiation and conduction are essentially constant and the earth’s surface temperature will vary according to increasing back IR radiation (radiation forcing from CO2 and water vapour) being offset by surface IR emission and latent heat of evaporation. At a global average surface temperature of 15C the rate of increase of surface IR emission with temperature is about 5 W/m2 per degree C and the rate of increase of latent energy from evaporation is of similar magnitude. This means that back IR radiation from doubling of CO2 concentration must be at least 10 W/m2 to sustain a 1C temperature rise and more than 30 W/m2 to sustain a 3C temperature rise. Using the most accurate line-by-line radiation calculations the increase in back IR radiation due to doubling of CO2, increasing atmospheric temperature by 3C and holding relative humidity constant (the full positive feedback effect at 3C) only produces an increase in back IR radiation of 18 W/m2, well short of the 30 W/m2 necessary to sustain a 3C increase in equilibrium surface temperature. The rapidly increasing surface IR emission and latent heat loss with temperature are a barrier to significant surface temperature increase unless there is a change in the solar radiation input (either directly or through a change to cloudiness and albedo).
Secondly, the emphasis on CO2 emission reduction (so-called ‘clean coal’) is encouraging research in the wrong areas. Oil, gas, coal and uranium are all non-renewable sources of energy. Global demand is already causing price increases but the real concern will be as supplies become seriously depleted and more difficult to extract. The latter may not be in this century but will surely come. Investment in geosequestration and other forms of ‘clean coal’ are increasing the amount of resource needed to produce each unit of energy by up to 30 percent (according to one IPCC report). That is, we are contemplating using the non-renewable resource 30 percent faster (and bringing the effective lifetime forward by 30 percent) in order to achieve the chimera of CO2 emission reduction. Very poor policy if we are considering the needs of future generations!
AGW is a fiction and a very dangerous fiction.
Australasian Climate Research
and author of Climate Change: A Natural Hazard