A team of geologists in Australia has recently published a study in Geology, pointing to a decline in volcanic carbon dioxide (CO2) emissions as a key factor in sparking this ice age. Lead author Dr. Adriana Dutkiewicz, an ARC Future Fellow, explains: “Imagine Earth almost completely frozen over. That’s exactly what happened about 700 million years ago. However, the precise causes of the extreme cooling have remained uncertain—until now.” To investigate, scientists turned to advanced plate tectonic models to track Earth’s shifting landmasses and volcanic activity.Their research reveals that around 717 million years ago, CO2 emissions from mid-ocean ridges dropped to an all-time low. Volcanic activity at these ridges typically releases CO2, a greenhouse gas that warms the planet. Its reduction caused Earth’s atmosphere to lose a key heat-trapping component, leading to a significant temperature drop and triggering global glaciation.
