"climate change advocate", in contrast to some "climate change opponent"?
An Advocate/activist is someone who puts politics and policy ahead of science and economics, and it isn't limited to climate change either.
For example, it was gay advocacy/activists not heath sciences professionals who made sure more money was spent on Aids/HIV than all childhood diseases combined.
Yeah, this sounds like someone who doesn't realize that climate change is a real effect driven by CO2 emissions, regardless of the precise economics of renewable energy.