Actually, if you read some of the more recent back-and-forth scientific discourse regarding the "ultimate" cause of the extinction of the dinosaurs, the climate change component has regained some of its former stature. No one is denying the Chicxulub happened or that it had a significant influence, but there is apparent evidence that some dinosaurs survived for a significant period of time after the impact. Furthermore, for about 1 million years prior to the impact, the Deccan Trap volcanism was taking place (India was passing over the Reunion hotspot, see map below) and that apparently had a global climate effect, too. So, though the interpretation is tentative, it appears that climate change set up the dinosaurs for a fall, Chicxulub pushed most of them over the edge, and continuing climate change finished off the remnant survivors.
To get back on topic, every time I point out to the 'global warming' nuts that the earth was so warm during the Mesozoic that BOTH Antarctica and Alaska (which were in about the same positions as they are today on the globe) supported temperate rainforests,
If they were knowledgeable, that information shouldn't bother them. CO2 concentration peaked for the Mesozoic at about the beginning of the Cretaceous (approx. 6x modern) and declined through the period; it was close to modern at the K/T boundary.
Late Cretaceous continental positions (and sea levels) 