Recent warming in the Arctic, which has been amplified during the winter1,2,3, greatly enhances microbial decomposition of soil organic matter and subsequent release of carbon dioxide (CO2)4. However, the amount of CO2 released in winter is not known and has not been well represented by ecosystem models or empirically based estimates5,6. Here we synthesize regional in situ observations of CO2 flux from Arctic and boreal soils to assess current and future winter carbon losses from the northern permafrost domain. We estimate a contemporary loss of 1,662 TgC per year from the permafrost region during the winter season (October–April). This loss is greater than the average growing season carbon uptake for this region estimated from process models (−1,032 TgC per year). Extending model predictions to warmer conditions up to 2100 indicates that winter CO2 emissions will increase 17% under a moderate mitigation scenario—Representative Concentration Pathway 4.5—and 41% under business-as-usual emissions scenario—Representative Concentration Pathway 8.5. Our results provide a baseline for winter CO2 emissions from northern terrestrial regions and indicate that enhanced soil CO2 loss due to winter warming may offset growing season carbon uptake under future climatic conditions.
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Data are archived and freely available at the Oak Ridge National Laboratory Distributed Active Archive Center. The synthesis dataset is available at https://doi.org/10.3334/ORNLDAAC/1692. Monthly carbon flux maps (25 km, October–April, 2003–2018; 2018–2100 for RCP 4.5 and RCP 8.5) are available at https://doi.org/10.3334/ORNLDAAC/1683.
Huang, J. Recently amplified Arctic warming has contributed to a continual global warming trend. Nat. Clim. Change 7, 875–879 (2017).
Koenigk, T. et al. Arctic Climate Change in 21st century CMIP5 simulations with EC-Earth. Clim. Dynam. 40, 2719–2743 (2013).
Cohen, J. et al. Recent Arctic amplification and extreme mid-latitude weather. Nat. Geosci. 7, 627–637 (2014).
Schadel, C. et al. Potential carbon emissions dominated by carbon dioxide from thawed permafrost soils. Nat. Clim. Change 6, 950–953 (2016).
Fisher, J. B. et al. Carbon cycle uncertainty in the Alaskan Arctic. Biogeosciences 11, 4271–4288 (2014).
Commane, R. et al. Carbon dioxide sources from Alaska driven by increasing early winter respiration from Arctic tundra. Proc. Natl Acad. Sci. USA 114, 5361–5366 (2017).
Elberling, B. & Brandt, K. K. Uncoupling of microbial CO2 production and release in frozen soil and its implications for field studies of Arctic C cycling. Soil Biol. Biochem. 35, 263–272 (2003).
Schuur, E. A. G. et al. Climate change and the permafrost carbon feedback. Nature 520, 171–179 (2015).
Belshe, E. F., Schuur, E. A. G. & Bolker, B. M. Tundra ecosystems observed to be CO2 sources due to differential amplification of the carbon cycle. Ecol. Lett. 16, 1307–1315 (2013).
McGuire, A. D. et al. An assessment of the carbon balance of Arctic tundra: comparisons among observations, process models, and atmospheric inversions. Biogeosciences 9, 3185–3204 (2012).
Schimel, D. et al. Observing terrestrial ecossytems and the carbon cycle from space. Glob. Change Biol. 21, 1762–1776 (2014).
Parazoo, N., Commane, R., Wofsy, S. C. & Koven, C. D. Detecting regional patterns of changing CO2 flux in Alaska. Proc. Natl Acad. Sci. USA 113, 7733–7738 (2016).
Grogan, P. Cold season respiration across a low Arctic landscape: the influence of vegetation type, snow depth, and interannual climatic variation. Arct. Antarct. Alp. Res. 44, 446–456 (2012).
Michaelson, G. J. & Ping, C. L. Soil organic carbon and CO2 respiration at subzero temperature in soils of Arctic Alaska. J. Geophys. Res. Atmos. 108(D2), 8164 (2005).
Rogers, M. C., Sullivan, P. F. & Welker, J. M. Evidence of nonlinearity in the response of net ecosystem CO2 exchange to increasing levels of winter snow depth in the high Arctic of Northwestern Greenland. Arct. Antarct. Alp. Res. 43, 95–106 (2011).
Wang, T. et al. Controls on winter ecosystem respiration in temperate and boreal ecosystems. Biogeosciences 8, 2009–2025 (2011).
Zona, D. et al. Cold season emissions dominate the Arctic tundra methane budget. Proc. Natl Acad. Sci. USA 113, 40–45 (2016).
Schaefer, K. & Jafarov, E. A parameterization of respiration in frozen soils based on substrate availability. Biogeosciences 13, 1991–2001 (2016).
Monson, R. et al. Winter forest soil respiration controlled by climate and microbial community composition. Nature 439, 711–714 (2006).
Welker, J. M., Fahnestock, J. T. & Jones, M. H. Annual CO2 flux in dry and moist Arctic tundra: field responses to increases in summer temperatures and winter snow depth. Climatic Change 44, 139–150 (2000).
Natali, S. M. et al. Effects of experimental warming of air, soil and permafrost on carbon balance in Alaskan tundra. Glob. Change Biol. 17, 1394–1407 (2011).
Webb, E. E. et al. Increased wintertime CO2 loss as a result of sustained tundra warming. Biogeosciences 121, 1–17 (2016).
Christiansen, C. T., Schmidt, N. M. & Michelsen, A. High Arctic dry heath CO2 exchange during the early cold season. Ecosystems 15, 1083–1092 (2012).
Knutti, R., Masson, D. & Gettelman, A. Climate model genealogy: generation CMIP5 and how we got there. Geophys. Res. Lett. 40, 1194–1199 (2013).
Forkel, M. et al. Enhanced seasonal CO2 exchange caused by amplified plant productivity in northern ecosystems. Science 351, 696–699 (2016).
Tucker, C. Reduction of air- and liquid water-filled soil pore space with freezing explains high temperature sensitivity of soil respiration below 0 °C. Soil Biol. Biochem. 78, 90–96 (2014).
Loranty, M. M. et al. Reviews and syntheses: changing ecosystem influences on soil thermal regimes in northern high-latitude permafrost regions. Biogeosciences 15, 5287–5313 (2018).
Witze, A. Snow-sensing fleet to unlock water’s icy secrets. Nature 532, 17 (2016).
Natali, S. M. et al. Permafrost thaw and soil moisture driving CO2 and CH4 release from upland tundra. J. Geophys. Res. Biogeosci. 120, 525–537 (2015).
Euskirchen, E. S., Bret-Harte, M. S., Shaver, G. R., Edgar, C. W. & Romanovsky, V. E. Long-term release of carbon dioxide from Arctic tundra ecosystems in Alaska. Ecosystems 20, 960–974 (2017).
Tramontana, G. et al. Predicting carbon dioxide and energy fluxes across global FLUXNET sites with regression algorithms. Biogeosciences 13, 4291–4313 (2016).
Koven, C. D. et al. Permafrost carbon-climate feedbacks accelerate global warming. Proc. Natl Acad. Sci. USA 108, 14769–14774 (2011).
Slater, A. G. & Lawrence, D. M. Diagnosing present and future permafrost from climate models. J. Clim. 26, 5608–5623 (2013).
Vanhala, P. et al. Temperature sensitivity of soil organic matter decomposition in southern and northern areas of the boreal forest zone. Soil Biol. Biochem. 40, 1758–1764 (2008).
Hugelius, G. E. A. Estimated stocks of circumpolar permafrost carbon with quantified uncertainty ranges and identified data gaps. Biogeosciences 11, 6573–6593 (2014).
McGuire, A. D. et al. Dependence of the evolution of carbon dynamics in the northern permafrost region on the trajectory of climate change. Proc. Natl Acad. Sci. USA 115, 3882–3887 (2018).
Qian, H., Joseph, R. & Zeng, N. Enhanced terrestrial carbon uptake in the northern high latitudes in the 21st century from the Coupled Carbon Climate Model Intercomparison Project model projections. Glob. Change Biol. 16, 641–656.
Starr, G. O. et al. Photosynthesis of Arctic evergreens under snow: implications for tundra ecosystem carbon balance. Ecology 84, 1415–1420 (2003).
Treat, C. C., Bloom, A. A. & Marushchak, M. E. Nongrowing season methane emissions: a significant component of annual emissions across northern ecosystems. Glob. Change Biol. 24, 3331–3343 (2018).
Walter Anthony, K. et al. 21st-century modeled permafrost carbon emissions accelerated by abrupt thaw beneath lakes. Nat. Commun. 9, 3262 (2018).
Circum-Arctic Map of Permafrost and Ground-Ice Conditions, Version 2 (National Snow & Ice Data Center, 2002); https://nsidc.org/data/ggd318
Brodzik, M. J., Billingsley, B., Haran, T., Raup, B. & Savoie, M. H. EASE-Grid 2.0: incremental but significant improvements for Earth-gridded data sets. ISPRS Int. J. Geoinf. 1, 32–45 (2012).
R Core Team R: A Language and Environment for Statistical Computing (R Foundation for Statistical Computing, 2016).
Ridgeway, G. Generalized Boosted Models: A guide to the gbm package. R version 2.1.5 (2007).
Elith, J., Leathwick, J. R. & Hastie, T. A working guide to boosted regression trees. J. Anim. Ecol. 77, 802–813 (2008).
Hijmans, R. J., Phillips, S., Leathwick, J. & Elith, J. Dismo: Species distribution modelling. R version 1.1-4 (2017).
Bronaugh, D. W. Zyp: Zhang + Yue-Pilon trends package. R version 0.10-1.1 (2017).
Rogers, B. M., et. al. Impacts of climate change on fire regimes and carbon stocks of the US Pacific Northwest. J. Geophys. Res. Biogeosci. 116, G03037 (2011).
Leathwick, J. R., Elith, J., Francis, M. P., Hastie, T. & Taylor, P. Variation in demersal fish species richness in the oceans surrounding New Zealand: an analysis using boosted regression trees. Mar. Ecol. Prog. Ser. 321, 267–281 (2006).
This study was supported by funding from NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE; grant no. NNX15AT81A to S.M.N.), with additional funding from NASA New Investigator Program (grant no. NNX17AF16G to J.D.W.), National Science Foundation (grant nos. 955713 and 1331083 to E.A.G.S.; no. 1503559 to E.E.J.), the Next-Generation Ecosystem Experiments Arctic Project, Department of Energy Office of Science to E.E.J., Department of Energy Office of Science, Office of Biological and Environmental Research to J.D.J and R.M. (grant no. DE-AC02-06CH11357), National Research Foundation of Korea (grant nos. NRF-2016M1A5A1901769 and KOPRI-PN-19081 to B.-Y.L. and Y.K.), and funds that supported the data included in this synthesis.
The author declare no competing interests.
Peer review information Nature Climate Change thanks John Campbell and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Natali, S.M., Watts, J.D., Rogers, B.M. et al. Large loss of CO2 in winter observed across the northern permafrost region. Nat. Clim. Chang. 9, 852–857 (2019). https://doi.org/10.1038/s41558-019-0592-8
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