While the Atlantic Meridional Overturning Circulation (AMOC) is expected to weaken under increasing GHGs, it is unclear how it would respond to stabilization of global warming of 1.5 or 2.0 °C, the Paris Agreement temperature targets, or 3.0 °C, the expected warming by 2100 under current emission reduction policies. On the basis of stabilized warming simulations with two Earth System Models, we find that, after temperature stabilization, the AMOC declines for 5–10 years followed by a 150-year recovery to a level that is approximately independent of the considered stabilization scenario. The AMOC recovery has important implications for North Atlantic steric sea-level rise, which by 2600 is simulated to be 25–31% less than the global mean, and for North Atlantic surface temperatures, which continue to increase despite global mean surface temperature stabilization. These results show that substantial ongoing climate trends are likely to occur after global mean temperature has stabilized.
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Python scripts to create the figures are available at https://gitlab.com/michael.sigmond/amoc_stab. The CanESM2 transient warming simulations are freely available at http://open.canada.ca/data/en/dataset/aa7b6823-fd1e-49ff-a6fb-68076a4a477c. All ZECMIP simulations that were branched off at the point that the diagnosed emissions reached 1,000 PgC are freely available on the portal of the Earth System Grid Federation. Data from the other simulations are available upon request.
Vellinga, M. & Wood, R. A. Impacts of thermohaline circulation shutdown in the twenty-first century. Clim. Change 91, 43–63 (2008).
Jackson, L. C. et al. Global and European climate impacts of a slowdown of the AMOC in a high resolution GCM. Clim. Dynam. 45, 3299–3316 (2015).
Yin, J., Griffies, S. M. & Stouffer, R. J. Spatial variability of sea level rise in twenty-first century projections. J. Clim. 23, 4585–4607 (2010).
Gregory, J. M. et al. The Flux-Anomaly-Forced Model Intercomparison Project (FAFMIP) contribution to CMIP6: investigation of sea-level and ocean climate change in response to CO2 forcing. Geosci. Model Dev. 9, 3993–4017 (2016).
Saenko, O. A., Yang, D. & Myers, P. G. Response of the North Atlantic dynamic sea level and circulation to Greenland meltwater and climate change in an eddy-permitting ocean model. Clim. Dynam. 49, 2895–2910 (2017).
IPCC Climate Change 2013: The Physical Science Basis (eds Stocker, T. F. et al.) (Cambridge Univ. Press, 2013).
Weaver, A. J. et al. Stability of the Atlantic Meridional Overturning Circulation: a model intercomparison. Geophys. Res. Lett. 39, L20709 (2012).
Cheng, W., Chiang, J. C. H. & Zhang, D. Atlantic meridional overturning circulation (AMOC) in CMIP5 models: RCP and historical simulations. J. Clim. 26, 7187–7197 (2013).
IPCC Special Report on Global Warming of 1.5 °C (eds Masson-Delmotte, V. et al.) (WMO, 2018).
Maher, N. et al. The Max Planck Institute Grand Ensemble: enabling the exploration of climate system variability. J. Adv. Model. Earth Syst. 11, 2050–2069 (2019).
Mitchell, D. et al. Realizing the impacts of a 1.5 °C warmer world. Nat. Clim. Change 6, 735–737 (2016).
James, R., Washington, R., Schleussner, C. F., Rogelj, J. & Conway, D. Characterizing half-a-degree difference: a review of methods for identifying regional climate responses to global warming targets. WIREs Clim. Change 8, e457 (2017).
Sigmond, M., Fyfe, J. C. & Swart, N. C. Ice-free Arctic projections under the Paris Agreement. Nat. Clim. Change 8, 404–408 (2018).
Sanderson, B. M. et al. Community climate simulations to assess avoided impacts in 1.5 and 2 °C futures. Earth Syst. Dynam. 8, 827–847 (2017).
Jahn, A. Reduced probability of ice-free summers for 1.5 °C compared to 2 °C warming. Nat. Clim. Change 8, 409–413 (2018).
Graff, L. S. et al. Arctic amplification under global warming of 1.5 and 2 °C in NorESM1-Happi. Earth Syst. Dynam. 10, 569–598 (2019).
Rogelj, J. et al. Perspective: Paris agreement climate proposals need boost to keep warming well below 2 °C. Nat. Clim. Change 534, 631–639 (2016).
Swart, N. C. et al. The Canadian Earth System Model version 5 (CanESM5.0.3). Geosci. Model Dev. 12, 4823–4873 (2019).
Jones, C. D. et al. The Zero emissions commitment model intercomparison project (ZECMIP) contribution to C4MIP: quantifying committed climate changes following zero carbon emissions. Geosci. Model Dev. 12, 4375–4385 (2019).
Gillett, N. P., Arora, V. K., Zickfeld, K., Marshall, S. J. & Merryfield, W. J. Ongoing climate change following a complete cessation of carbon dioxide emissions. Nat. Geosci. 4, 83–87 (2011).
Drijfhout, S., van Oldenborgh, G. J. & Cimatoribus, A. Is a decline of AMOC causing the warming hole above the North Atlantic in observed and modeled warming patterns? J. Clim. 25, 8373–8379 (2012).
Menary, M. B. & Wood, R. A. An anatomy of the projected North Atlantic warming hole in CMIP5 models. Clim. Dynam. 50, 3063–3080 (2018).
Gregory, J. M. et al. A model intercomparison of changes in the Atlantic thermohaline circulation in response to increasing atmospheric CO2 concentration. Geophys. Res. Lett. 32, L12703 (2005).
De Boer, A. M., Gnanadesikan, A., Edwards, N. R. & Watson, A. J. Meridional density gradients do not control the Atlantic overturning circulation. J. Phys. Oceanogr. 40, 368–380 (2010).
McCarthy, G. D. et al. Measuring the Atlantic Meridional Overturning Circulation at 26° N. Prog. Oceanogr. 130, 91–111 (2015).
Rahmstorf, S. On the freshwater forcing and transport of the Atlantic thermohaline circulation. Clim. Dynam. 12, 799–811 (1996).
Gent, P. R. A commentary on the Atlantic Meridional Overturning Circulation stability in climate models. Ocean Model. 122, 57–66 (2018).
Liu, W., Xie, S. P., Liu, Z. & Zhu, J. Overlooked possibility of a collapsed Atlantic Meridional Overturning Circulation in warming climate. Sci. Adv. 3, 1–8 (2017).
Mecking, J. V., Drijfhout, S. S., Jackson, L. C. & Andrews, M. B. The effect of model bias on Atlantic freshwater transport and implications for AMOC bi-stability. Tellus A 69, 1–15 (2017).
Mecking, J. V., Drijfhout, S. S., Jackson, L. C. & Graham, T. Stable AMOC off state in an eddy-permitting coupled climate model. Clim. Dynam. 47, 2455–2470 (2016).
Jackson, L. C. & Wood, R. A. Hysteresis and resilience of the AMOC in an eddy-permitting GCM. Geophys. Res. Lett. 45, 8547–8556 (2018).
Matthews, H. D. & Caldeira, K. Stabilizing climate requires near-zero emissions. Geophys. Res. Lett. 35, L04705 (2008).
Arora, V. K. et al. Carbon emission limits required to satisfy future representative concentration pathways of greenhouse gases. Geophys. Res. Lett. 38, 3–8 (2011).
Meinshausen, M. et al. The RCP greenhouse gas concentrations and their extensions from 1765 to 2300. Clim. Change 109, 213–241 (2011).
Arora, V. K. & Scinocca, J. F. Constraining the strength of the terrestrial CO2 fertilization effect in the Canadian Earth System Model version 4.2 (CanESM4.2). Geosci. Model Dev. 9, 2357–2376 (2016).
We thank Duo Yang for performing the CanESM5 simulations, Yanjun Jiao for technical assistance, and Bill Merryfield and Vivek Arora for their helpful comments on an earlier draft.
The authors declare no competing interests.
Peer review information Nature Climate Change thanks Andreas Schmittner and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Sigmond, M., Fyfe, J.C., Saenko, O.A. et al. Ongoing AMOC and related sea-level and temperature changes after achieving the Paris targets. Nat. Clim. Chang. 10, 672–677 (2020). https://doi.org/10.1038/s41558-020-0786-0