The U.N.-based IPCC (Intergovernmental Panel on Climate Change) produced its latest report in 2007 (AR4). Its position on global warming (based on the outputs of computerized climate models) indicates that the models only depend on anthropogenic CO2 after 1970 – prior to that, warming and cooling is explained by natural factors . So even though industrial civilizations have been producing increased amounts of CO2 since the late 1800s, it only becomes a factor in the models after 1970. The following figure combines the IPCC AR4 figure SPM-3 and the temperature anomalies 1850 – 2008 (Hadley Centre data [ http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/ ] – the data used by the IPCC).

Thus in just over 10 years, the consensus switched from global cooling to global warming – but the definition of climate is “average weather over 30 years”. So how did this sudden switch come about, along with its definitive a priori assumption of “human-induced climate change”?

The IPCC was formed in 1988 with the purpose of assessing “the scientific, technical and socioeconomic information relevant for the understanding of the risk of human-induced climate change. ” -- i.e. its main goal is based on the assumption of “human-induced climate change” – there was never an attempt to evaluate the scientific evidence of the cause . The IPCC released reports in 1990, 1996, 2001 and 2007. Although the IPCC has become the “definitive” authority and always makes statements regarding the definite human causation and upcoming disaster, it has never provided substantial scientific evidence that anthropogenic CO2 is the cause. The only evidence provided is a correlation with CO2 since 1950, but mainly the output of computer models. Solar irradiance is not incorporated.