Open access

Attributing long-term sea-level rise to Paris Agreement emission pledges

Edited by Arild Underdal, University of Oslo, Oslo, Norway, and approved September 19, 2019 (received for review April 30, 2019)
November 4, 2019
116 (47) 23487-23492

Significance

Sea-level rise poses a threat to coastal areas and will continue for centuries, even after global mean temperature has stabilized. Research assessing the implications of current international climate mitigation efforts usually focuses on 21st century climate impacts. The multicentennial sea-level rise commitment of pledged near-term emission reduction efforts under the Paris Agreement has not been quantified yet. We here estimate this sea-level rise commitment and find that pledged emissions until 2030 lock in 1-m sea-level rise in the year 2300. Our analysis highlights the defining role of present-day emissions for future sea-level rise and points to the potential of reducing the long-term sea-level-rise commitment by more ambitious national emission reduction targets.

Abstract

The main contributors to sea-level rise (oceans, glaciers, and ice sheets) respond to climate change on timescales ranging from decades to millennia. A focus on the 21st century thus fails to provide a complete picture of the consequences of anthropogenic greenhouse gas emissions on future sea-level rise and its long-term impacts. Here we identify the committed global mean sea-level rise until 2300 from historical emissions since 1750 and the currently pledged National Determined Contributions (NDC) under the Paris Agreement until 2030. Our results indicate that greenhouse gas emissions over this 280-y period result in about 1 m of committed global mean sea-level rise by 2300, with the NDC emissions from 2016 to 2030 corresponding to around 20 cm or 1/5 of that commitment. We also find that 26 cm (12 cm) of the projected sea-level-rise commitment in 2300 can be attributed to emissions from the top 5 emitting countries (China, United States of America, European Union, India, and Russia) over the 1991–2030 (2016–2030) period. Our findings demonstrate that global and individual country emissions over the first decades of the 21st century alone will cause substantial long-term sea-level rise.

Continue Reading

Data Availability

Data deposition: Pathway as well as projection data and code to reproduce the results shown in this study can be accessed at: https://gitlab.com/anauels/ndc_slr_attribution.

Acknowledgments

A.N., J.G., and C.-F.S. acknowledge support by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (16_II_148_Global_A_IMPACT). C.-F.S. further acknowledges support by the German Federal Ministry of Education and Research (01LN1711A). J.G. further acknowledges support by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (FKZ 3717181030).

References

1
P. P. Wong et al., “Coastal systems and low-lying areas” in Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel of Climate Change, C. B. Field et al., Eds. (Cambridge University Press, Cambridge, UK, 2014).
2
B. Neumann, A. T. Vafeidis, J. Zimmermann, R. J. Nicholls, Future coastal population growth and exposure to sea-level rise and coastal flooding–A global assessment. PLoS One 10, e0118571 (2015).
3
B. Marzeion, A. Levermann, Loss of cultural world heritage and currently inhabited places to sea-level rise. Environ. Res. Lett. 9, 34001 (2014).
4
A. Markham, E. Osipova, K. Lafrenz Samuels, A. Caldas, World Heritage and Tourism in a Changing Climate (United Nations Environment Programme, Nairobi, Kenya and United Nations Educational, Scientific and Cultural Organization, Paris, 2016).
5
J. A. Church et al., “Sea level change” in Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, T. F. Stocker et al., Eds. (Cambridge University Press, Cambridge, UK, 2013).
6
C. C. Hay, E. Morrow, R. E. Kopp, J. X. Mitrovica, Probabilistic reanalysis of twentieth-century sea-level rise. Nature 517, 481–484 (2015).
7
R. S. Nerem et al., Climate-change–driven accelerated sea-level rise detected in the altimeter era. Proc. Natl. Acad. Sci. 115, 2022–2025 (2018).
8
X. Zhang, J. A. Church, Sea level trends, interannual and decadal variability in the Pacific Ocean. Geophys. Res. Lett. 39, L21701 (2012).
9
P. U. Clark et al., Consequences of twenty-first-century policy for multi-millennial climate and sea-level change. Nat. Clim. Chang. 6, 360–369 (2016).
10
A. Levermann et al., The multimillennial sea-level commitment of global warming. Proc. Natl. Acad. Sci. U.S.A. 110, 13745–13750 (2013).
11
M. Mengel, A. Nauels, J. Rogelj, C.-F. Schleussner, Committed sea-level rise under the Paris agreement and the legacy of delayed mitigation action. Nat. Commun. 9, 601 (2018).
12
P. U. Clark et al., Sea-level commitment as a gauge for climate policy. Nat. Clim. Chang. 8, 653–655 (2018).
13
UNFCCC, Aggregate effect of the intended nationally determined contributions: An update, Synthesis report by the secretariat (United Nations Framework Convention on Climate Change, Rio de Janeiro, 2016).
14
UNEP, The Emissions Gap Report 2018 (United Nations Environment Programme, Nairobi, 2018).
15
A. Nauels, M. Meinshausen, M. Mengel, K. Lorbacher, T. M. L. Wigley, Synthesizing long-term sea level rise projections–The MAGICC sea level model v2.0. Geosci. Model Dev. 10, 2495–2524 (2017).
16
M. Mengel et al., Future sea level rise constrained by observations and long-term commitment. Proc. Natl. Acad. Sci. U.S.A. 113, 2597–2602 (2016).
17
M. Meinshausen, S. C. B. Raper, T. M. L. Wigley, Emulating coupled atmosphere-ocean and carbon cycle models with a simpler model, MAGICC6–Part 1: Model description and calibration. Atmos. Chem. Phys. 11, 1417–1456 (2011).
18
S. R. M. Ligtenberg, W. J. van de Berg, M. R. van den Broeke, J. G. L. Rae, E. van Meijgaard, Future surface mass balance of the Antarctic ice sheet and its influence on sea level change, simulated by a regional atmospheric climate model. Clim. Dyn. 41, 867–884 (2013).
19
A. Levermann et al., Projecting Antarctic ice discharge using response functions from SeaRISE ice-sheet models. Earth Syst. Dynam. 5, 271–293 (2014).
20
A. Nauels, J. Rogelj, C.-F. Schleussner, M. Meinshausen, M. Mengel, Linking sea level rise and socioeconomic indicators under the shared socioeconomic pathways. Environ. Res. Lett. 12, 114002 (2017).
21
R. M. DeConto, D. Pollard, Contribution of Antarctica to past and future sea-level rise. Nature 531, 591–597 (2016).
22
T. L. Edwards et al., Revisiting Antarctic ice loss due to marine ice-cliff instability. Nature 566, 58–64 (2019).
23
IPCC, “Summary for policymakers” in Global Warming of 1.5°C. An IPCC Special Report on the Impacts of Global Warming of 1.5°C above Pre-Industrial Levels and Related Global Greenhouse Gas Emission Pathways, in the Context of Strengthening the Global Response to the Threat of Climate Change, V. Masson-Delmotte et al., Eds. (World Meteorological Organization, Geneva, 2018), p. 32.
24
J. Gütschow, M. L. Jeffery, M. Schaeffer, B. Hare, Extending near-term emissions scenarios to assess warming implications of Paris agreement NDCs. Earths Futur. 6, 1242–1259 (2018).
25
CAT, Some progress since Paris, but not enough, as governments amble towards 3° C of warming. (2018). https://climateactiontracker.org/publications/warming-projections-global-update-dec-2018/. Accessed 1 April 2019.
26
J. Gütschow, M. L. Jeffery, R. Gieseke, The PRIMAP-Hist National Historical Emissions Time Series (1850–2016) (V. 2.0, 2019). https://doi.org/10.5880/PIK.2019.001. Accessed 1 April 2019.
27
L. D. Trusel et al., Divergent trajectories of Antarctic surface melt under two twenty-first-century climate scenarios. Nat. Geosci. 8, 927–932 (2015).
28
B. Hare, M. Meinshausen, How much warming are we committed to and how much can be avoided? Clim. Change 75, 111–149 (2006).
29
K. Zickfeld et al., Long-term climate change commitment and reversibility: An EMIC intercomparison. J. Clim. 26, 5782–5809 (2013).
30
D. Ehlert, K. Zickfeld, What determines the warming commitment after cessation of CO2emissions? Environ. Res. Lett. 12, 15002 (2017).
31
Y. Wada et al., Fate of water pumped from underground and contributions to sea-level rise. Nat. Clim. Chang. 6, 777–780 (2016).
32
S. C. Lewis, S. E. Perkins-Kirkpatrick, G. Althor, A. D. King, L. Kemp, Assessing contributions of major emitters’ Paris-era decisions to future temperature extremes. Geophys. Res. Lett. 46, 3936–3943 (2019).
33
C. Le Quéré et al., Global carbon budget 2018. Earth Syst. Sci. Data 10, 2141–2194 (2018).
34
M. Meinshausen, T. M. L. Wigley, S. C. B. Raper, Emulating atmosphere-ocean and carbon cycle models with a simpler model, MAGICC6-Part 2: Applications. Atmos. Chem. Phys. 11, 1457–1471 (2011).
35
M. Meinshausen et al., The RCP greenhouse gas concentrations and their extensions from 1765 to 2300. Clim. Change 109, 213–241 (2011).
36
M. Meinshausen et al., Historical greenhouse gas concentrations for climate modelling (CMIP6). Geosci. Model Dev. 10, 2057–2116 (2017).
37
M. Meinshausen et al., Multi-gas emissions pathways to meet climate targets. Clim. Change 75, 151–194 (2006).
38
J. Gütschow et al., The PRIMAP-hist national historical emissions time series. Earth Syst. Sci. Data 8, 571–603 (2016).
39
M. Meinshausen et al., Greenhouse-gas emission targets for limiting global warming to 2 degrees C. Nature 458, 1158–1162 (2009).
40
J. Rogelj, M. Meinshausen, R. Knutti, Global warming under old an new scenarios using IPCC climate sensitivity range estimates. Nat. Clim. Chang. 2, 248–253 (2012).
41
J. Rogelj, M. Meinshausen, J. Sedláček, R. Knutti, Implications of potentially lower climate sensitivity on climate projections and policy. Environ. Res. Lett. 9, 31003 (2014).
42
P. Friedlingstein et al., Uncertainties in CMIP5 climate projections due to carbon cycle feedbacks. J. Clim. 27, 511–526 (2014).
43
D. Le Bars, S. Drijfhout, H. de Vries, A high-end sea level rise probabilistic projection including rapid Antarctic ice sheet mass loss. Environ. Res. Lett. 12, 44013 (2017).
44
T. E. Wong et al., BRICK v0.1, a simple, accessible, and transparent model framework for climate and regional sea-level projections. Geosci Model Dev Discuss 2017, 1–36 (2017).
45
R. E. Kopp et al., Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections. Earths Futur. 5, 1217–1233 (2017).
46
N. R. Golledge et al., Global environmental consequences of twenty-first-century ice-sheet melt. Nature 566, 65–72 (2019).

Information & Authors

Information

Published in

Go to Proceedings of the National Academy of Sciences
Go to Proceedings of the National Academy of Sciences
Proceedings of the National Academy of Sciences
Vol. 116 | No. 47
November 19, 2019
PubMed: 31685608

Classifications

    Data Availability

    Data deposition: Pathway as well as projection data and code to reproduce the results shown in this study can be accessed at: https://gitlab.com/anauels/ndc_slr_attribution.

    Submission history

    Published online: November 4, 2019
    Published in issue: November 19, 2019

    Keywords

    1. sea-level rise
    2. Paris Agreement
    3. emission pledges

    Acknowledgments

    A.N., J.G., and C.-F.S. acknowledge support by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (16_II_148_Global_A_IMPACT). C.-F.S. further acknowledges support by the German Federal Ministry of Education and Research (01LN1711A). J.G. further acknowledges support by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (FKZ 3717181030).

    Notes

    This article is a PNAS Direct Submission.
    See Commentary on page 23373.

    Authors

    Affiliations

    Climate Analytics, 10969 Berlin, Germany;
    Australian-German Climate & Energy College, The University of Melbourne, Parkville, VIC 3010, Australia;
    Potsdam Institute for Climate Impact Research, D-14412 Potsdam, Germany;
    Potsdam Institute for Climate Impact Research, D-14412 Potsdam, Germany;
    Australian-German Climate & Energy College, The University of Melbourne, Parkville, VIC 3010, Australia;
    Potsdam Institute for Climate Impact Research, D-14412 Potsdam, Germany;
    College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331-5503;
    School of Geography and Environmental Sciences, University of Ulster, BT52 1SA Coleraine, Northern Ireland, United Kingdom;
    Carl-Friedrich Schleussner https://orcid.org/0000-0001-8471-848X
    Climate Analytics, 10969 Berlin, Germany;
    Potsdam Institute for Climate Impact Research, D-14412 Potsdam, Germany;
    Integrative Research Institute on Transformations of Human–Environment Systems (IRI THESys), Humboldt-Universität zu Berlin, 10099 Berlin, Germany

    Notes

    1
    To whom correspondence may be addressed. Email: [email protected].
    Author contributions: A.N. and C.-F.S. designed research; A.N. and J.G. performed research; A.N. and J.G. analyzed data; and A.N., J.G., M. Mengel, M. Meinshausen, P.U.C., and C.-F.S. wrote the paper.

    Competing Interests

    The authors declare no competing interest.

    Metrics & Citations

    Metrics

    Note: The article usage is presented with a three- to four-day delay and will update daily once available. Due to ths delay, usage data will not appear immediately following publication. Citation information is sourced from Crossref Cited-by service.


    Citation statements

    Altmetrics

    Citations

    If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.

    Cited by

      Loading...

      View Options

      View options

      PDF format

      Download this article as a PDF file

      DOWNLOAD PDF

      Get Access

      Login options

      Check if you have access through your login credentials or your institution to get full access on this article.

      Personal login Institutional Login

      Recommend to a librarian

      Recommend PNAS to a Librarian

      Purchase options

      Purchase this article to get full access to it.

      Single Article Purchase

      Attributing long-term sea-level rise to Paris Agreement emission pledges
      Proceedings of the National Academy of Sciences
      • Vol. 116
      • No. 47
      • pp. 23365-23862

      Media

      Figures

      Tables

      Other

      Share

      Share

      Share article link

      Share on social media