The entire hypothesis That CO2 will cause harmful warming rest on the idea that increases on a trace gas CO2 creates a positive feedback loop with Water Vapor that causes the greenhouse effect. In the absence of the proposed positive feedback effect there is no runaway warming, if the feedbacks are negative the climate system is stable (absent outside factors ie: Changes in Solar activity, Cosmic rays in the atmosphere, the Solar System position in the Galaxy and so on). To review the scientific method for a moment (as opposed to claims of consensus which is a political not a scientific term). You proposed a hypothesis, in this case Human CO2 production creates a positive feedback with water vapor which causes temperature increase. Then you create a mathematical model that describes the process. This model defines boundary conditions, assumption of basic parameters and variables, initial conditions, and inputs to the model. Then you run iterations of the model to see how the system should change over time. When you see the results of the model, you then compare the results of the model with measurements of the system IOW you compare what your model predicts with observations of how the Real World behaves. If you model's predictions match observation you have a good model that describes the system accurately. If observation doesn't match the model then the model is wrong, some assumption or parameter is wrong and you modify the model. SO what is the sensitivity of the Climate to CO2, a high sensitivity indicates a positive feedback, a low sensitivity indicates a negative feedback (IOW the effect of doubling atmospheric CO2 will be marginal maybe .1C) So how do the predictions of the Climate models match observation? here are 2 links with a brief summary: Does CO? heat the troposphere ? | Watts Up With That? http://sciencespeak.com/SimpleHotspot.pdf So the climate model that is the basis for the Climate Disruption narrative doesn't match observation, there are errors. The predicted did not occur where it was supposed to occur if the models were correct. Here is a more complete paper (26 pages) on the Hot Spot predicted by the Hansen and his modeling buddies at CRU and what observation actually shows: http://sciencespeak.com/MissingSignature.pdf]Does CO? heat the troposphere ? | Watts Up With That? So now the question is where are the problems in the models used by the alarmist? These two papers deal with the atmosphere and the greenhouse effect the first deals with the assumptions made in the Hansen/CRU climate models and how the relate to boundary conditions. These are peer reviewed papers. The first is 40 pages: http://met.hu/idojaras/IDOJARAS_vol111_No1_01.pdf The abstract for the paper: The bolded area is the important the assumptions in the models overestimates the sensitivity of the climate to CO2 forcing. This paper does not deal with observations directly, they deal with mathematical issues in the models, how the green house is models and errors in the boundary conditions (ie the alarmistmodels assume the atmosphere has infinite thickness, which you can easily disprove by trying to breathe at the peak of Mt Everest). continued next 2 post.