My field is paleoanthropology, where I’ve focused on the relationship between large scale change in climate (like the spread of grassland habitats, or the cooling of the Earth since the Miocene) and the evolution of our family, genus, and species. So when people say “climate has changed before,” I get it. How does one understand the importance of ongoing anthropogenic climate change in the context of such large, long term change?
A partial answer to that question: 1) most changes in the past have been slower; 2) When they were fast they were devastating; and 3) our genius emerged less than 2 million years ago, and our species less than a half million years ago. Everything recently adapted about us is adapted to a cooler environment than the one we are heading for now. You think climate change super-charged storms are bad? Well, they are, but when a three degree latitude band around the equator becomes uninhabitable by mammals, that point will become very clear.
If you go to the Skeptical Science web site, my go-to web resource for climate science denial answers, you’ll see “Climate’s changed before” right at the top of the list of “Most Used Climate Mythis” (left sidebar). Click that, then click the “intermediate” tab, and you’ll find the Skeptical Science answer to that myth, with excellent graphics.
Skeptical Science does not shy away from complex and nuanced questions. It is the single best, and most comprehensive, source of description and explanation for both climate science denial and the science itself. Skeptical Science links peer reviewed research with the thoughtful study of communication and brings them right to your uncle Bob.