Bob Tisdale's analysis of climate models' shows that there is no agreement on the magnitude of Earth's top-of-atmosphere energy imbalance in the models. There are even wider disagreements in the three calculated components that make up that energy budget, how they evolved in the past, and how they may evolve in the future. This indicates there is little agreement in the modeled processes and physics that contribute to global warming.
An irreducibly simple climate-sensitivity
model is designed to empower even non-specialists to
research the question how much global warming we may
cause. The IPCC AR5 report reduced its feedback estimates which requires a reduction in its climate sensitivity estimate from 3.2 to 2.2 C for a doubling of CO2. The authors argue that the net feedbacks are likely to be net-negative, so that the warming from GHG emissions without any policy changes are likely less that 1 C this century.
Dr. John Christy gives testimony to the U.S. Committee on Natural Resources about his analysis of the impact of proposed U.S. regulation on climate. He shows comparisons of climate model projection versus satellite and weather balloon observation. Climate models on average over predict global warming by a factor of three, and by a factor of four in the tropics. Dr. Christy shows eliminating all U.S. emissions today would reduce global temperatures by 0.05 to 0.08 Celsius, assuming a climate sensitivity of 1.8 C per doubling of CO2. He says there is evidence that climate sensitivity is less than 1.8 C, which would reduce this estimate further.
Dr. Patrick J. Michaels, a climatologist and guest speaker at the 5th Annual Friends of Science Luncheon writes, "year after year, the hole that climate scientists have buried themselves in gets deeper and deeper. The longer that they wait to admit their overheated forecasts were wrong, the more they are going to harm all of science." Referring to a graph prepared by Dr. John Christy, climatologist and guest speaker at the 7th Annual Friends of Science Luncheon, Michaels says there is a "remarkable disconnect between predicted global warming and the real world."
John Christy presented the graph to the House Committee on Natural Resources on May 15, 2015.
Dr. William Gray, Professor Emeritus of Colorado State University, writes,
"There are many flaws in the global climate models. But the largest flaw is a result of the climate model’s inability to realistically deal with the small horizontal scale (and model unresolvable) changes brought about by the globe’s thousands of individual deep cumulonimbus (Cb) cloud elements. An increase in the totality of these deep Cb convective units adds drying to the upper troposphere. This is in contrast to the assumptions implicit in the General Climate Model (GCM) simulations which increase upper tropospheric water-vapor as a result of enhanced rainfall and Cb convection associated with rising levels of CO2." The upper-level drying leads to extra infrared radiation loss to space, resulting in a negative water vapor feedback.