Subglacial Weathering Slowed Earth’s Escape from Snowball Earth
A new study from the Earth-Life Science Institute (ELSI) at the Institute of Science Tokyo challenges long-held assumptions about Earth’s most extreme ice ages. Researchers have discovered that chemical weathering likely continued beneath thick continental ice sheets during “snowball Earth” events, consuming atmospheric carbon dioxide (CO₂) and potentially prolonging these periods of global glaciation. The findings, published on March 10, 2026, offer a new explanation for the varying durations of ancient global glaciations.
Challenging Conventional Wisdom
Earth’s climate has undergone dramatic shifts throughout its history, including periods where ice extended from the poles to the equator – known as snowball Earth events. These glaciations profoundly impacted Earth’s surface environment and played a crucial role in the evolution of climate, oceans, and life. A key question has been why some snowball Earth events lasted significantly longer than others.
Traditionally, the deglaciation process has been attributed to the carbon cycle. The prevailing theory suggested that volcanic emissions would gradually increase CO₂ levels in the atmosphere, eventually triggering greenhouse warming and melting the ice. However, this model assumed that chemical weathering ceased beneath the extensive ice sheets.
Subglacial Weathering: A Previously Unrecognized Feedback
The ELSI research team utilized numerical geochemical models to investigate water-rock interactions in subglacial environments. Their simulations focused on conditions beneath thick continental ice sheets, where geothermal heat and ice insulation can generate meltwater at the glacier base. This meltwater, flowing through crushed rock, allows chemical reactions to occur even in a globally frozen climate.
“Our results demonstrate that subglacial weathering represents a previously unrecognised feedback mechanism that could account for the dramatically different durations of Neoproterozoic snowball Earth events,” says Shintaro Kadoya, lead author of the study and a Specially Appointed Assistant Professor at ELSI, Institute of Science Tokyo [1].
CO₂ Consumption and Prolonged Glaciations
The models revealed that subglacial weathering could consume substantial amounts of CO₂, potentially offsetting greenhouse gas buildup from volcanic emissions. Under plausible snowball Earth conditions, the estimated CO₂ consumption rates approached those of volcanic CO₂ emissions, effectively slowing atmospheric warming and delaying deglaciation. This process could explain why some snowball Earth events, like the Sturtian glaciation, persisted for tens of millions of years.
The study also suggests that variations in subglacial hydrology and erosion rates could lead to differing weathering intensities between glaciations, potentially accounting for the contrasting durations of Neoproterozoic snowball Earth events.
Implications Beyond Climate
Beyond its impact on climate, subglacial weathering may have also influenced ocean chemistry and nutrient supply. Meltwater from beneath ice sheets could have delivered elements like phosphorus to the oceans, potentially boosting biological productivity once the ice retreated. This highlights subglacial environments as dynamic chemical reactors, rather than inert frozen landscapes.
Future Research
Co-author Mohit Melwani Daswani, Associate Professor at ELSI, Institute of Science Tokyo, adds, “This finding challenges a central assumption of the classical snowball Earth hypothesis by showing that weathering can continue beneath ice sheets and significantly influence climate.” [2]. Further research will focus on refining these models and exploring the complex interplay between subglacial weathering, ocean circulation, and the evolution of life during Earth’s most extreme ice ages.
Reference: Shintaro Kadoya¹*, Mohit Melwani Daswani¹,², Continued continental weathering during snowball Earth mitigated greenhouse gas buildup and prolonged global glaciation, Earth and Planetary Science Letters, DOI: 10.1016/j.epsl.2026.119837