Well, between climategate, and the examples of Josh Willis, Judith Curry and many others we know that if you report cooling or take a skeptical position you get viciously attacked, and skeptical articles are hard to publish.
Judith Curry stated that when she become a skeptic if she wasn't a senior educator she would have been out of a job and she was disinvited from conferences. For a young scientist, being a skeptic is a career ender.
Willis initially said the Argos network showed cooling and was so viciously attacked he had to rework the data.
Mann et. al. got skeptical journal editors fired and loaded peer review panels with global warmers and we have the email evidence to prove it.
If you are going to attack people and end careers when people publish or say things that you disagree with, it is easy to get a consensus.
Senator: Use RICO Laws to Prosecute Global Warming Skeptics
Let alone the numerous people who suggested jailing skeptics. Sheldon Whitehouse, a Democratic Senator from Rhode Island suggested using RICO statutes against skeptics and also said they should be put in jail. This is not how America has traditionally resolved disagreements about differences of data interpretation and opinion.
A consensus of people with a gun to their head isn't a consensus. And with many skeptics driven from the field it isn't hard to achieve a consensus.