There is of course much more wrong with state-of-the-art global circulation models (climate models) than the assumption and implementation of CO2-H2O feedback. Although these models are among the most elaborate predictive models of complex non-linear phenomena, they are nonetheless sweeping oversimplifications of the global climate system and its mechanistic intricacies.
This paper provides further evidence that the multi-decadal global climate models are significantly overstating the water vapor input into the atmosphere, and thus are not providing quantitatively realistic estimates of how the climate system responds to the increase in atmospheric well mixed greenhouse gases in terms of the water vapor feedback. This water vapor feedback is required in order to achieve the amount of warming from radiative forcing projected in the 2007 IPCC report.
Marine Geophysical Professor
With the complete discrediting of the ‘hockey stick’ curve of recent temperature change (McIntyre and McKitrick, 2003, 2005; Wegman, Scott and Said, 2006) that was the icon of their report, the IPCC case for dangerous human-caused warming now rests only on ambiguous anecdotal evidence, unvalidated computer models and misleading attribution studies (IPCC, 2007).
The [climate] models solve the equations of fluid dynamics, and they do a very good job of describing the fluid motions of the atmosphere and the oceans. They do a very poor job of describing the clouds, the dust, the chemistry, and the biology of fields and farms and forests. Many basic processes of planetary ecology are poorly understood. They must be better understood before we can reach an accurate diagnosis of the present condition of our planet.
The claim that anthropogenic CO2 is responsible for the current warming of Earth climate is scientifically insupportable because climate models are unreliable. ... It turns out that uncertainties in the energetic responses of Earth climate systems are more than 10 times larger than the entire energetic effect of increased CO2. If the uncertainty is larger than the effect, the effect itself becomes moot.