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Please stop the cherry-picking, taking isolated reports out of context.
Thousands of scientists in a whole range of disciplines are working in the field. All of the scientific organizations they belong to - the NAS, the American Geophysical Union, and many others - say that humans are changing climate in potentially catastrophic ways. Here's the AGU statement:
http://www.agu.org/sci_soc/policy/positions/climate_change2008.shtml
Yes, you can find vaguely convincing sounding statements from pressure groups that contradict this, and you can make up conspiracy theories about scientists making stuff up to get grants. And you can pull up statements made by individuals (not these organizations) in the past about climate that were wrong.
That doesn't change the bottom line. A consensus does exist among scientists on the subject. The political issues, and what specifically should be done is another topic. But it all has to start with the science, and the science is there.