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Imminent loss of climate space for permafrost peatlands in Europe and Western Siberia

Abstract

Human-induced climate warming by 2100 is expected to thaw large expanses of northern permafrost peatlands. However, the spatio-temporal dynamics of permafrost peatland thaw remain uncertain due to complex permafrost–climate interactions, the insulating properties of peat soils and variation in model projections of future climate. Here we show that permafrost peatlands in Europe and Western Siberia will soon surpass a climatic tipping point under scenarios of moderate-to-high warming (Shared Socioeconomic Pathway (SSP) 2-4.5, SSP3-7.0 and SSP5-8.5). The total peatland area affected under these scenarios contains 37.0–39.5 Gt carbon (equivalent to twice the amount of carbon stored in European forests). Our bioclimatic models indicate that all of Fennoscandia will become climatically unsuitable for peatland permafrost by 2040. Strong action to reduce emissions (SSP1-2.6) by the 2090s could retain suitable climates for permafrost peatlands storing 13.9 Gt carbon in northernmost Western Siberia, indicating that socio-economic policies will determine the rate and extent of permafrost peatland thaw.

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Fig. 1: Distributions of the suitable climate space for permafrost peatlands in Europe and Western Siberia during the modern baseline period (1961–1990).
Fig. 2: Future climate space for permafrost peatlands in Europe and Western Siberia.
Fig. 3: Comparisons of the total peat carbon that is within the suitable climate envelopes for peatland permafrost in Europe and Western Siberia under four CMIP6 emission scenarios.

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Data availability

The modern observational climate data were extracted from the CRU TS v.4.04 dataset (https://crudata.uea.ac.uk/cru/data/hrg/cru_ts_4.04/), the CMIP6 projections of twenty-first-century climate are available at their native resolution from the Earth System Grid Federation (https://esgf-node.llnl.gov/search/cmip6/), the modern peatland extents were primarily estimated using PEATMAP (http://archive.researchdata.leeds.ac.uk/251/) and the original SOC maps are available from the Bolin Centre Database (https://bolin.su.se/data/hugelius-2020). Any remaining data used to produce this research are included in the Supplementary Information and in Supplementary Data 1 and 2.

Code availability

The Python code used to extract modern climate normals and to downscale and bias-correct CMIP6 climate projections is available from https://github.com/refewster/Imminent-loss-of-climate-space-for-Eurasian-permafrost-peatlands-.

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Acknowledgements

R.E.F. is in receipt of a UK Natural Environment Research Council Training Grant (no. NE/S007458/1). A.M.P. is grateful for support from the Russian Science Foundation, grant no. 20-67-46018. The work of A.M.P. was carried out according to the state assignment of ISSA SB RAS. C.J.S. was supported by a NERC/IIASA Collaborative Research Fellowship (no. NE/T009381/1).

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R.E.F., P.J.M., R.F.I. and G.T.S. designed the research. R.E.F. conducted the research and led manuscript development, with contributions from all authors. A.M.P. contributed the landform classification data for Western Siberia. C.J.S. provided analysis of future climate projections from CMIP6 models.

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Correspondence to Richard E. Fewster.

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Fewster, R.E., Morris, P.J., Ivanovic, R.F. et al. Imminent loss of climate space for permafrost peatlands in Europe and Western Siberia. Nat. Clim. Chang. 12, 373–379 (2022). https://doi.org/10.1038/s41558-022-01296-7

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