"There are reputable climate scientist such as Dr. Roy Spencer, Dr. Richard Lindzen who disagree with the doomsday scenarios of Al Gore and Dr. James Hansen."
But there are millions upon millions of scientists in the world, so of course some will disagree. For instance, today Stephen Hawking (reputable scientist) said it would disastrous for us to try and contact aliens and we should stop attempting to do so, yet there are other reputable scientists trying to contact alien life. There were scientists who didn't think things like walking on the moon nor the atomic bomb were possible. There are still scientists arguing over cold fusion. The YEC whackos can even point to scientists who don't think the Earth is billions of years old. The realities are that the overwhelming majority of scientists are currently in the opinion that we are contributing to global warming. You can see a list in my other response to "Anonymous."
60 Minutes Interview with Dr. Hansen: http://www.cbsnews.com/stories/2006/03/17/60minutes/main1415985.shtml