What makes thawing permafrost more permeable?

Thawing permafrost releases greenhouse gases faster than before

Experiments by University of Leeds researchers found that thawing permafrost becomes far more permeable than frozen ground, which can accelerate how gases escape to the atmosphere.

The reported effect is large: thawing permafrost can become about 25 to 100 times more permeable compared with when it is frozen. Permeability controls how easily water, gases, and other materials move through the pore spaces in soil and ice-rich ground.

What changed when the ground thawed

As permafrost thaws due to climate warming, the physical structure changes—ice that helped lock materials in place melts, and the soil can become more open to gas flow. The experiments quantify that change and provide a mechanism that helps explain why warming can trigger faster greenhouse-gas emissions.

By measuring gas fraction and gas permeability of thawing permafrost in controlled settings, the researchers translated the physical shift into an emission-relevant property: gases can move more readily through the thawed material.

Why it matters

Permafrost ecosystems store vast amounts of carbon. If thawing increases gas escape rates, then the climate system can warm more quickly, which can further thaw more permafrost—a positive feedback.

The new results are significant because they don’t just restate that thaw releases gases; they describe a specific, measurable pathway by which the release can accelerate. That can improve future climate models and help policymakers and communities better anticipate how fast the Arctic could contribute to global warming.

Uncertainty that remains

The studies quantify permeability changes, but the pace of real-world emissions also depends on local soil types, water availability, vegetation, and extreme events—details that are not specified in the provided summary.