Unveiling Earth's Past: Microfossils and Oceans in the Climate Change Story

To know what Earth’s climate was like millions of years ago — and thus also what to expect in our current era of rapid global warming — scientists look to the fossils of tiny plankton that floated around past oceans. But these plankton are made of calcium carbonate, like the limescale in your kettle, and like limescale they will dissolve in vinegar, or, in this context, in an ocean undergoing acidification. Enter radiolarians: plankton that make their beautifully intricate skeletons out of glass. Can they fill the gaps in our knowledge of climate past and help us understand what comes next?

How often do you think about the sea? I suspect pretty rarely. What about the wider blue stage? How it works? What role it's playing in the climate crisis? If it has always worked this way? I would like, if I may, to take you on a strange journey, which began a little over 4 billion years ago. Our protagonist is the ocean tide: a deceptively simple ebb and flow that has sculpted coastlines, raised and levelled ocean ecosystems and, at least in part, produced and maintained our present climate. Hopefully, you’ll soon find reason to think about the deep parts of our climate just a little more.