It's misleading to compare climate change trends across a timeframe of just two millennia. The extent and significance of anthropogenic global warming is relevant on a geological time scale (i.e. across millions of years) and should be measured as such
Yes, it's true. The Earth is currently very cool. Over the eons it's usually been much warmer than it is now (technically the Earth is still in an Ice Age). It's also worth noting, since the late Carboniferous Period, the Earth has been encased in a comparatively carbon-depleted atmosphere (as carbon became trapped in oil/gas beneath the ground)
Notwithstanding the above, the climate and oceans, while still relatively cold and carbon-depleted, are warming and soaking up carbon at a rate faster than has occurred at any point in Earth's 4 billion year history. Even faster than the massive thermal spike occurring at the end of the Permian Period c. 250 million years ago (which made 97% of life in Earth extinct by the way)
My point is, the human species evolved, during the past several million years, in a very cold and carbon-depleted climate. But the Earth is warming at an extremely rapid pace. Jelly fish and cockroaches may thrive in a warmer, carbon-enriched world but I fear we will not.
