If there is such thing as a credible global warming skeptic, they would need to meaningfully confront two powerful facts before their opinions can be taken seriously:
1) That a comprehensive review of all peer reviewed scientific studies through the past decade found every one of them confirmed that global warming is occuring and human made greenhouse gases are to blame. And,This represents both the widespread corruption of our news media, and dismal level of critical thinking in our public discourse. Both will need to be confronted to solve global warming.
2) That despite overwhelming scientific consensus, more than half of all news media articles surveyed give as much support to climate change 'skeptics' as they do to sound climate science.
See Al Gore's commentary below.
Clip via Hugg.com