"However, even ignoring this central question,
there actually is much that can be learned simply by sticking to matters where there is
widespread agreement. For example, there is widespread agreement that CO2 levels have increased from about 280ppm to 360ppm over the past century, and,
that combined with increases in other greenhouse gases, this brings us about half way to the radiative forcing associated with a doubling of CO2 without any evidence of enhanced human misery.

that the increase in global mean temperature over the past century is about 1F which is smaller than the normal interannual variability for smaller regions like North America and Europe, and comparable to the interannual variability for the globe. Which is to say that temperature is always changing, which is why it has proven so difficult to demonstrate human agency.

that doubling CO2 alone will only lead to about a 2F increase in global mean temperature. Predictions of greater warming due to doubling CO2 are based on positive feedbacks from poorly handled water vapor and clouds (the atmosphere’s main greenhouse substances) in current computer models. Such positive feedbacks have neither empirical nor theoretical foundations. Their existence, however, suggests a poorly designed earth which responds to perturbations by making things worse.

that the most important energy source for extratropical storms is the temperature difference between the tropics and the poles which is predicted by computer models to
decrease with global warming. This also implies reduced temperature variation associated with weather since such variations result from air moving from one latitude to
another. Consistent with this, even the IPCC Policymakers Summary notes that no significant trends have been identified in tropical or extratropical storm intensity and
frequence. Nor have trends been found in tornados, hail events or thunder days.

that warming is likely to be concentrated in winters and at night. This is an empirical result based on data from the past century. It represents what is on the whole a beneficial pattern.

that temperature increases observed thus far are less than what models have suggested should have occurred even if they were totally due to increasing greenhouse emissions.
The invocation of very uncertain (and unmeasured) aerosol effects is frequently used to disguise this. Such an invocation makes it impossible to check models. Rather, one is reduced to the claim that it is possible that models are correct.

that claims that man has contributed any of the observed warming (ie attribution) are based on the assumption that models correctly predict natural variability. Such claims,
therefore, do not constitute independent verifications of models. Note that natural variability does not require any external forcing – natural or anthropogenic.

that large computer climate models are unable to even simulate major features of past climate such as the 100 thousand year cycles of ice ages that have dominated climate for the past 700 thousand years, and the very warm climates of the Miocene, Eocene, and
Cretaceous. Neither do they do well at accounting for shorter period and less dramatic phenomena like El Niños, quasi-biennial oscillations, or intraseasonal oscillations – all of which are well documented in the data.

that major past climate changes were either uncorrelated with changes in CO2 or were
characterized by temperature changes which preceded changes in CO2 by 100's to
thousands of years.

that increases in temperature on the order of 1F are not catastrophic and may be beneficial.

that Kyoto, fully implemented, will have little detectable impact on climate regardless of what one expects for warming. This is partly due to the fact that Kyoto will apply only to developed nations. However, if one expected large global warming, even the extension of Kyoto to developing nations would still leave one with large warming"

From Senate Committee- linked in above post- 2 May 2001