The computer models used by the Intergovernmental Panel on Climate Change to “predict” global warming were built by correlating past global temperatures with past carbon dioxide levels, and then introducing a few “fudge” factors to make sure the models fit the data (just remember that correlation does not imply causation).
The models are very good at “predicting” the past temperature fluctuations upon which they were based. These models were then used to predict what future global temperatures would be, assuming that levels of atmospheric carbon dioxide were the primary factor influencing global temperatures.
The IPCC computer models continue to predict unrelenting global warming as carbon dioxide levels continue to increase. However, there has been no increase in global warming for the past 18 years (Remote Sensing Systems’ satellite-based monthly global mean lower-troposphere temperature dataset) even though the atmospheric concentration of carbon dioxide has continued to increase from 0.0365 to 0.0401 percent (this is analogous to adding 2.3 people to the population of Davis over the past 18 years).
The discrepancy between the predicted and actual global temperature is rapidly increasing; i.e., the models are becoming increasingly inaccurate. I am sure new computer models will be created to better fit the new data, but unless the assumptions underlying the models are correct (i.e., verified by unbiased testing using new data, not by back testing against the very data set that was used to create the model), they may be just as unreliable as the current models.
It is obvious that we currently do not have sufficient understanding of the factors affecting global climate to predict how the climate will change in a few decades, much less in a century. Should we base critical economic decisions using predictions from the current flawed model, or should we take prudent actions to mitigate the near-term effects of the changing climate while engaging in open scientific research so we can devise a model that actually could predict future climatic changes?