H/T to JHS for referencing this video at Watching the Deniers.
The burden of proof is on deniers to demonstrate that anthropogenic climate change is not happening and/or serious to make the argument to do nothing about it. Why? Because everyone who actually knows about this stuff says it is and to do nothing is to risk our planet remaining habitable. These are pretty high stakes to bet on the word of crackpots like Monckton, Bob Carter, Steve McIntyre or Anthony Watts.