The soils of the North American Arctic contain substantially more organic carbon than previously thought, according to a study published online this week in Nature Geoscience. Carbon stored in high-latitude soils could potentially be released to the atmosphere as CO2 or methane in response to climate change.
Chien-Lu Ping and colleagues used measurements of soil organic carbon to estimate the size of the entire North American Arctic soil organic carbon store. They sampled a wide range of landscapes, to at least 1 metre in depth, to provide a comprehensive assessment of the carbon pool in the region. Previous estimates of the Arctic carbon pool relied heavily on measurements conducted outside of the Arctic in the very top layers of the soil.
In his accompanying News and Views, Christian Beer says “Ping and colleagues calculate a total carbon content...equivalent to approximately one sixth of the current carbon content in the atmosphere. Releasing even a portion of this carbon…would have a significant impact on Earth’s climate”.