Can a 62-million-year-old ‘hyperthermal’ event hold the clues to our uncertain future climate?

Climate change has been rising to an ever-increasing prominence in the news headlines in recent years, as local and global temperature records are obliterated, and extreme weather events occur with increasing frequency and severity. Preparing for an uncertain future climate represents one of the biggest challenges humans have ever faced. Here, I take you back 62 million years ago (Ma) to a poorly studied short-lived global warming event known as the Latest Danian Event (LDE), which may represent a good analogue for current human-induced climate change. I discuss evidence for changes in temperature and pH of the oceans during the LDE, using novel geochemical proxies on the calcite shells of zooplankton to prove that the LDE was the first global ‘hyperthermal’ event of the Cenozoic. I also delve into the potential forcing mechanisms behind the event, outlining the critical outstanding questions which palaeoclimatologists are yet to answer. Most importantly, I highlight the lessons we can learn from the LDE about our future climate, allowing us to better plan, prepare and adapt.