Overview
- The peer-reviewed study, led by researchers from the Universities of Melbourne and Sydney, appears in Communications Earth & Environment with a 540‑million‑year reconstruction of carbon fluxes.
- Model results point to mid-ocean ridges and continental rifts as the dominant natural CO2 sources behind transitions between icehouse and greenhouse states for most of Earth history.
- Deep-sea carbon-rich sediments emerge as pivotal: oceans sequester carbon into seafloor rocks that later release CO2 when carried into subduction zones.
- Volcanic-arc emissions became relatively more important only in the past roughly 100–120 million years, a shift linked to the rise and spread of planktic calcifiers that boosted carbonate burial.
- The authors emphasize that today’s human-driven CO2 release is occurring far faster than geological processes, underscoring the exceptional pace of modern climate change.