The earth warmed after the last ice age. Since that time there have been extended periods when the average temperature has been significantly higher than it is today, and signicant periods of cold. The last cold period, the Little Ice Age, ended in the early 19th century, and the temperature trend since then has been slightly upward.

The unaltered records show that average temperatures did not uniformly increase during the 20th century. The trend was up until about 1940, down from 1940-1980, and up from 1980-2000. Since that time there has been no warming--the trend has been flat.

Congressional testimony by James Hanson of NASA in 1988 was stage set for maximum effect. Scheduled during the average hottest week of the summer, Democratic operatives disabled the airconditioning in the room the night before, and opened the curtains to ensure the maximum solar heating. During that testimony, Dr. Hanson presented three curves showing his projections for temperature increases under three carbon dioxide emission scenarios. Even Scenario C, the best case with severe actions taken to reduce carbon dioxide emissions, showed a large upweard trend in temperatures.

Carbon dioxide emissions were not reduced and pretty much followed the "business as usual" assumptions of Scenario A, yet temperature failed to increase as much as predicted by the best case Scenario C. The predictions are falsified by the data. The models based on carbon dioxide as the only driver of global temperature have no predictive skill.

During the ensuring decades, Dr. Hanson has used his position at NASA GISS to alter the historical temperature records to bolster his claims. These alterations are done clandestinely and without any open discussion, much less peer reviewed in the open literature. As such they have no scientific validity.

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