The IPCC has claimed in IPCC AR-4, Chapter 9, Executive Summary, that “Greenhouse gas forcing has very likely caused most of the observed global warming over the last 50 years.” This appears to be incorrect because R2 including the influence of CO2 is not significantly different from R2 assuming CO2 has no influence.
All those organizations that agree with the Climate Science Community ‘Consensus’ had accepted what the Consensus claimed because they assumed that these Climate Scientists were the experts and had figured it out. In fact, the Consensus had not ‘figured it out’. They did not identify a cause and instead assumed that it must be atmospheric CO2 because they couldn’t think of anything else. This was reinforced by the observation that CO2 and average global temperature increased together from 1973 to 2005 (or at least for the 22 years from 1976 to 1998).
However, while CO2 has continued to rise, the temperature has stopped rising. From 2001 through September, 2011 the atmospheric CO2 increased by 23.6% of the total increase from 1800 to 2001 while the average global temperature has not increased. The 23.6% CO2 increase is the significant measurement, not the comparatively brief time period.
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