"For every single scientist that tells you (global warming is) happening and that it's our fault...I can stack up another group of reports that say just the opposite."
Tom Tancredo on Tuesday, May 15th, 2007 in Columbia, S.C.
Most scientists say humans cause warming
In fact, the stacks would be pretty lopsided.
Tancredo is wrong to suggest that climate scientists are evenly split. The overwhelming consensus among them is that humans are the main cause of global warming.
A recent study by the Intergovernmental Panel on Climate Change, a group of scientists from more than 130 nations, concluded that there is overwhelming evidence that warming is caused by human activity.
Their February 2007 report said warming was "unequivocal" and that most of it has been caused by greenhouse gas concentrations caused by humans. The report said that humans have caused a significant increase in atmospheric concentrations of carbon dioxide, methane, and nitrous oxide since 1750.
Yes, there have been dissenting studies over the years about global warming. But the IPCC is an effort to forge an international consensus. It has included more than 2,500 expert reviewers, more than 800 authors and more than 450 lead authors working for the past six years.
Published: Tuesday, June 12th, 2007 at 12:00 a.m.
Subjects: Environment
Sources:
Intergovernmental Panel on Climate ChangeWritten by: Bill Adair
Researched by: Bill Adair
Edited by: Scott Montgomery
We want to hear your suggestions and comments.
For tips or comments on our Obameter and our GOP-Pledge-O-Meter promise databases, please e-mail the Obameter. If you are commenting on a specific promise, please include the wording of the promise.
For comments about our Truth-O-Meter or Flip-O-Meter items, please e-mail the Truth-O-Meter. We’re especially interested in seeing any chain e-mails you receive that you would like us to check out. If you send us a comment, we'll assume you don't mind us publishing it unless you tell us otherwise.Keep up to date with Politifact:
- Sign up for our e-mail (about once a week)
- Put a free PolitiFact widget on your blog or Web page
- Subscribe to our RSS feeds on Truth-O-Meter items
- Subscribe to our RSS feeds on GOP Pledge-O-Meter items
- Subscribe to our RSS feeds on Obameter items
- Follow us on Twitter
- Fan us on Facebook
- Advertise on PolitiFact
- Shop the PolitiFact store for T-shirts, hats and other PolitiFact swag
