A 2009 paper published in the International Journal of Forecasting states, in erudite terminology, that a "benchmark model" of climate, the "benchmark model" simply being that the climate will not change, resulted in climate change forecasting errors from 1851-1975 seven times less than the IPCC model which attributes climate change primarily to CO2 levels:
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In other words, the IPCC model of climate change forecasting is, as Einstein might quip, "not even wrong". The paper goes on to say, scientist tongue apparently planted firmly in cheek, that "decision makers who had assumed that temperatures would not change [instead of what the IPCC model predicts] would have had no reason for regret".
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