In NC, I'm not surprised by the bumper sticker ratio. In Malibu, which is about 94% white, at least 94% of drivers with O stickers are caucasian.
But back to climate: this notion that we are on a natural curve is spectacularly wrong. The rate of warming appears unprecedented. Where natural systems react to warming ("wild weather" and changes in flora and fauna) on a "natural" pace, this change is outpacing the ecosystem's natural reactions. The rate of glacial melt alone is beyond anything previously measured. Equally important is the thawing of "permafrost," which is largely decomposed matter that outgasses methane when warmed. There are over two billion acres of permafrost.
https://www.youtube.com/watch?v=zBd88rMinvg&feature=player_embedded