Here is some badly confused thinking: “Climate change is really basic physics. You can’t ‘believe in climate change or not’. That would be just like ‘you believe in gravity or not’.” (Dr Friederike Otto on BBC Inside Science)
Gravity is an obvious thing, which is immediately observable to everyone. Theories of gravity are not obvious, and reasonable people can disagree or be sceptical about them. Theories of gravity were developed in order to explain an obvious thing that people were aware of already.
Climate change is not an obvious thing, and it is not immediately observable to everyone. We have reason to believe in climate change, the thing, if we believe the theory of climate change. Unlike theories of gravity, the theory of climate change was not developed to explain an obvious thing that people were aware of already. It was the other way around: our confidence in the theory is our warrant for believing in the thing.
A person can only be “in denial” about something obvious, like gravity, the thing. No one can be “in denial” about something that is is not obvious, like a theory of gravity. Since neither the theory of climate change nor the thing is obvious, we should give up claims that sceptics about them can be in denial about them.