A strong mitigation scenario maintains climate neutrality of northern peatlands

Qiu, C., Ciais, P., Zhu, D., Guenet, B., Chang, J., Chaudhary, N., Kleinen, T., Li, X., Müller, J., Xi, Y., Zhang, W., Ballantyne, A., Brewer, S. C., Brovkin, V., Charman, D. J., Gustafson, A., Gallego-Sala, A. V, Gasser, T., Holden, J., … Westermann, S. (2022). A strong mitigation scenario maintains climate neutrality of northern peatlands. One Earth, 5(1), 86–97. https://doi.org/10.1016/j.oneear.2021.12.008

Summary

Intact peatlands remove carbon dioxide (CO2) from the atmosphere through photosynthesis and store the carbon in soils in waterlogged conditions, while emitting methane (CH4) to the atmosphere. The net climate impact of peatlands depends on the relative magnitude of these two greenhouse gases. In this study the authors assessed the future CO2 and CH4 balance of northern peatlands using five large-scale, process-based peatland models. Their results suggest that under climate policies and action, northern peatlands are likely be climate neutral because the climate-warming effect of peatland CH4 emissions is offset by the cooling effect of peatland CO2 sinks. However, if action on climate change is not taken, northern peatlands could accelerate global warming because CH4 emissions are projected to increase substantially, and northern peatlands may turn from CO2 sinks to sources driven by strong warming and drying.

Policy relevant message:

If action on climate change is not taken, northern peatlands could accelerate global warming because CH4 emissions are projected to increase substantially, and northern peatlands may turn from CO2 sinks to sources driven by strong warming and drying.