Permanently frozen soil, or permafrost, stores roughly double the amount of carbon currently in the atmosphere. Organic matter, like leaf litter, dead organisms, and plant roots, have accumulated in these soils for many years, preserved by freezing temperatures – until now. Temperatures in the Arctic are rising four times faster than the global average, thawing this soil, and waking up dormant microbes that decompose the now-available organic matter and release carbon dioxide (CO2) in the process.
With the potential to release massive amounts of CO2 into the atmosphere, scientists are urgently advocating for Earth Systems Models (ESM) to represent permafrost carbon dynamics, as most models fail to account for them at all. EESA scientists Charlie Koven and Bill Riley contributed to a recent Nature Climate Change publication emphasizing the importance of representing these dynamics in models to more accurately understand and predict climate change.
The authors also emphasize other effects of Arctic climate change that could impact the carbon budget and climate models. For example, since CO2 fuels photosynthesis, higher levels of CO2 will affect the amount of carbon absorbed by vegetation – a process that the research team explains is also not well represented in ESMs. The team also mentions that more frequent wildfires in Arctic regions directly emit carbon to the atmosphere and speed up carbon release from permafrost – another process missing accurate representation.
This paper helps to highlight not only the importance of Arctic ecosystems to the carbon cycle, but also, with reasonable representations, how models can significantly increase the accuracy of climate change projections. However, sustained funding opportunities are needed from government and private sectors to achieve this goal.