Aside from crazy conspiracy theorists, real skeptics of this would be people who acknowledge there is some climate change happening but it's not because of us. A lot of people simply believe it's a natural process. I don't know too much about it but I definitely don't believe the government or whoever is faking it.
I mean, it's not even a government entity that's reporting climate change. It's a bunch of independent, non-governmental scientists that are reporting it.
The government just follows up on their studies to see if they're legit or not. Honestly, an overwhelming majority of scientists (and data) points towards man-made climate change.