I find it even easier to ask them simply what the right temperature sbould be for planet earth? If they could be put in charge of God’s thermostat, what temperature would they set it at? Barring their ability to answer that, the obvious follow up is how can one say it’s getting too hot (or too cold) if one can’t say what the correct temperature should be?
Those are good questions.
A lot of the ones I run into think they are so “scientifically well informed”. I like to put those notions to rest very very quickly!