Snowball Earth: When Ice Reached the Tropics

Imagine sea ice near the equator, glaciers grinding across continents, and sunlight reflected back into space by a planet turning white. During the Cryogenian Period, Earth entered at least two extraordinary glacial intervals. The evidence is strong that ice reached very low latitudes. Inside this episode: - Ice At An Unlikely Latitude - A Climate Feedback With Its Foot On The Accelerator - Two Long Freezes, Not One Frozen Afternoon - How A White Planet Could Thaw Sources include peer-reviewed Earth-science research, official scientific institutions, and the episode's linked source record. This episode is a researched narrative summary. Historical records may be incomplete, translated differently, or interpreted differently by scholars. We distinguish documented facts, estimates, disputed interpretations, and later stories where material. Corrections are logged and incorporated into future editions. Follow Earth Before Humans for more researched journeys through deep time.