Details

Autor(en) / Beteiligte

• Qiu, Chunjing
• Ciais, Philippe
• Zhu, Dan
• Guenet, Bertrand
• Chang, Jinfeng
• Chaudhary, Nitin
• Kleinen, Thomas
• Li, XinYu
• Müller, Jurek
• Xi, Yi
• Zhang, Wenxin
• Ballantyne, Ashley
• Brewer, Simon C.
• Brovkin, Victor
• Charman, Dan J.
• Gustafson, Adrian
• Gallego-Sala, Angela V.
• Gasser, Thomas
• Holden, Joseph
• Joos, Fortunat
• Kwon, Min Jung
• Lauerwald, Ronny
• Miller, Paul A.
• Peng, Shushi
• Page, Susan
• Smith, Benjamin
• Stocker, Benjamin D.
• Sannel, A. Britta K.
• Salmon, Elodie
• Schurgers, Guy
• Shurpali, Narasinha J.
• Wårlind, David
• Westermann, Sebastian

Titel

A strong mitigation scenario maintains climate neutrality of northern peatlands

Ist Teil von

• One earth (Cambridge, Mass.), 2022-01, Vol.5 (1), p.86-97

Ort / Verlag

Elsevier Inc

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Northern peatlands store 300–600 Pg C, of which approximately half are underlain by permafrost. Climate warming and, in some regions, soil drying from enhanced evaporation are progressively threatening this large carbon stock. Here, we assess future CO2 and CH4 fluxes from northern peatlands using five land surface models that explicitly include representation of peatland processes. Under Representative Concentration Pathways (RCP) 2.6, northern peatlands are projected to remain a net sink of CO2 and climate neutral for the next three centuries. A shift to a net CO2 source and a substantial increase in CH4 emissions are projected under RCP8.5, which could exacerbate global warming by 0.21°C (range, 0.09–0.49°C) by the year 2300. The true warming impact of peatlands might be higher owing to processes not simulated by the models and direct anthropogenic disturbance. Our study highlights the importance of understanding how future warming might trigger high carbon losses from northern peatlands. [Display omitted] •Northern peatlands remain a CO2 sink of ∼0.1 Pg C year−1 until 2300 under RCP2.6•Northern peatlands become a CO2 source of ∼0.2 Pg C year−1 by 2300 under RCP8.5•CH4 emissions from northern peatlands will increase 5-fold by 2300 under RCP8.5•Modeling of peatland resilience, vegetation, and peat quality changes should be improved 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. Here, we assess the future CO2 and CH4 balance of northern peatlands using five large-scale, process-based peatland models. Our 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. Northern peatlands are one of the biggest terrestrial carbon pools, yet their response to climate change is uncertain. This study uses five state-of-the-art peatland models to project future CO2 and CH4 fluxes. Northern peatlands are projected to be climate neutral under a climate mitigation scenario consistent with the Paris Agreement goals, but they release CO2 and CH4 in the long term for high warming scenarios, exacerbating global warming by 0.21°C. The results suggest that climate mitigation efforts will prevent northern peatlands from amplifying climate warming.