When temperature rises slowly, ecosystems adapt in parallel to the change. When temperature rises fast, ecosystems don't. And so we have major die-offs of coral and trees, without corresponding colonization in places where they could now live.
When CO2 rises slowly, the ocean's pH is buffered by large deposits of calcium carbonate on the bottom. When CO2 rises fast, we get ocean acidification, which is on track to be the most extreme shellfish extinction event in the last 50 million years.
Therefore larger absolute past climate changes were less likely to have extreme impacts than faster present climate changes.
When temperature rises slowly, ecosystems adapt in parallel to the change. When temperature rises fast, ecosystems don't. And so we have major die-offs of coral and trees, without corresponding colonization in places where they could now live.
When CO2 rises slowly, the ocean's pH is buffered by large deposits of calcium carbonate on the bottom. When CO2 rises fast, we get ocean acidification, which is on track to be the most extreme shellfish extinction event in the last 50 million years.
Therefore larger absolute past climate changes were less likely to have extreme impacts than faster present climate changes.