Ancient Coccoliths Reveal a Cooler Miocene North Atlantic Than Expected

A Nature Communications study applies clumped-isotope geochemistry to exceptionally well-preserved fossil coccoliths to reconstruct 16 million years of North Atlantic temperatures, finding temperatures about 9°C cooler than previous alkenone-based estimates and closer to climate model simulations, challenging the view of extreme Miocene warmth and highlighting the need to re-evaluate climate proxies.