Dr Jack Barrett, of the Scientific Alliance wrote the paper entitled ‘Greenhouse molecules, their spectra and function in the atmosphere,’ to explain the properties of radiatively active molecules and how they affect the Earth’s atmosphere.
The spectroscopic properties of the molecules are incorporated into general circulation models (GCMs) and are used to indicate various degrees of enhancement of global warming caused by increases in their concentrations. Some climate sceptics hold the opinion that greenhouse gases have very little effect on the temperature of the atmosphere and the main body of climatologists, represented by the IPCC, state that they have a considerable effect, leading to a temperature rise of between 3 and 11 degrees C for a doubling of carbon dioxide. In my opinion, and in those of many climate sceptics, such results represent an exaggeration of the phenomenon and that a doubling of carbon dioxide should produce about 1 degree C rise in atmospheric temperature. One of the main positive feedbacks used by the IPCC to obtain their results is that of the spectroscopic effect of additional water vapour resulting from the rise of temperature following an increase in CO2. They seem not to allow for the extra water vapour contributing to greater cloud coverage, which is a negative feedback effect dependent upon the non-spectroscopic properties of water. Until such effects are properly incorporated into GCMs their results will not be acceptable to climate sceptics.