On the Mike McConnell radio show, there was a guest who's background is as an environmentalist. He wrote a book about global warming skeptics.
If you want to hear about experts who disagree with g.w. click on this link http://www.700wlw.com/cc-common/podc..._mcconnell.xml
and go to 8/7/08 hour two and click "listen". The good thing is that commercials and news aren't played, so a whole hour is condensed to about 38 minutes. The guest is on first ten minutes or so.