Subglacial geology and thermal conditions regulate methane emissions from Svalbard glaciers.

Subglacial geology and thermal conditions drive methane supersaturation, with concentrations reaching up to 425 times atmospheric levels in Svalbard glaciers.

• Why it matters: Understanding methane emissions from glaciers is crucial because they represent a significant, yet poorly quantified, source of atmospheric methane, impacting climate change models.
• What they did: The study analyzed meltwaters from 19 valley glaciers using isotopic and geophysical methods, revealing that methane is mainly thermogenic and linked to organic-rich, shale-dominated geology beneath temperate ice.
• The result: Findings suggest that melting glaciers in regions with organic-rich geology could substantially increase methane release, highlighting a potential feedback mechanism in global greenhouse gas emissions.