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The interplay of future emissions and geophysical uncertainties for projections of sea-level rise

Abstract

Uncertainty in future CO2 emissions and the geophysical response to emissions drives variability in future sea-level rise. However, the relative contributions of emissions and geophysical dynamics (for example, Antarctic Ice Sheet (AIS) tipping points) to future sea-level projections are not well understood. Here we disentangle their relative importance by propagating an ensemble of CO2 emissions trajectories through a calibrated carbon cycle–climate–sea-level model chain. Without negative emissions, the CO2 emissions trajectory, particularly the timing of when emissions are reduced, becomes the primary driver of sea-level variability between 2065 and 2075. Accelerated AIS melting greatly influences the sensitivity of global mean sea-level rise to time-averaged and integrated temperature changes. The most important geophysical uncertainties associated with the risk of exceeding sea-level thresholds are the threshold corresponding to accelerated AIS melting and equilibrium climate sensitivity. Our results highlight the need for both adaptation and rapid decarbonization to manage the risks posed by SLR.

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Fig. 1: Climate and sea-level impacts from emissions ensembles: summaries of simulations.
Fig. 2: Sensitivity of GMSLR to temperature changes.
Fig. 3: Time-varying feature importances for global mean sea-level projections.
Fig. 4: Delayed mitigation reduces the ‘safe operating space’ for avoiding GMSLR thresholds.

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Data availability

All input data used for the analysis are available with the code (in the data folder) except for the SNEASY–BRICK calibration results, which available from Zenodo via https://doi.org/10.5281/zenodo.6626335 (ref. 62) (see the GitHub README for guidance on which file to use). Simulation outputs from this experiment are available from Zenodo via https://doi.org/10.5281/zenodo.10373089 (ref. 63). Outputs for BRICK when forced by the Shared Socioeconomic Pathways are available from Zenodo via https://doi.org/10.5281/zenodo.14346558 (ref. 64).

Code availability

All code used for this analysis is available from Zenodo via https://doi.org/10.5281/zenodo.10391373 (ref. 65). This code is available under a GNU General Public License v.3.0.

References

  1. Ricke, K. L. & Caldeira, K. Maximum warming occurs about one decade after a carbon dioxide emission. Environ. Res. Lett. 9, 124002 (2014).

    Article  Google Scholar 

  2. Keller, K., Helgeson, C. & Srikrishnan, V. Climate risk management. Annu. Rev. Earth Planet. Sci. 49, 95–116 (2021).

    Article  CAS  Google Scholar 

  3. Milillo, P. et al. Heterogeneous retreat and ice melt of Thwaites Glacier, West Antarctica. Sci. Adv. 5, eaau3433 (2019).

    Article  CAS  Google Scholar 

  4. Alley, K. E. et al. Two decades of dynamic change and progressive destabilization on the Thwaites Eastern Ice Shelf. Cryosphere 15, 5187–5203 (2021).

    Article  Google Scholar 

  5. Miles, B. W. J. et al. Intermittent structural weakening and acceleration of the Thwaites Glacier Tongue between 2000 and 2018. J. Glaciol. 66, 485–495 (2020).

    Article  Google Scholar 

  6. Nöel, B. et al. Higher Antarctic ice sheet accumulation and surface melt rates revealed at 2 km resolution. Nat. Commun. 14, 1–11 (2023).

    Article  Google Scholar 

  7. Millan, R. et al. Rapid disintegration and weakening of ice shelves in North Greenland. Nat. Commun. 14, 6914 (2023).

    Article  CAS  Google Scholar 

  8. Choi, Y., Morlighem, M., Rignot, E. & Wood, M. Ice dynamics will remain a primary driver of Greenland ice sheet mass loss over the next century. Commun. Earth Environ. 2, 1–9 (2021).

    Article  Google Scholar 

  9. Lowry, D. P., Krapp, M., Golledge, N. R. & Alevropoulos-Borrill, A. The influence of emissions scenarios on future Antarctic ice loss is unlikely to emerge this century. Commun. Earth Environ. 2, 1–14 (2021).

    Article  Google Scholar 

  10. DeConto, R. M. & Pollard, D. Contribution of Antarctica to past and future sea-level rise. Nature 531, 591–597 (2016).

    Article  CAS  Google Scholar 

  11. DeConto, R. M. et al. The Paris Climate Agreement and future sea-level rise from Antarctica. Nature 593, 83–89 (2021).

    Article  CAS  Google Scholar 

  12. Mengel, M., Nauels, A., Rogelj, J. & Schleussner, C.-F. Committed sea-level rise under the Paris Agreement and the legacy of delayed mitigation action. Nat. Commun. 9, 601 (2018).

    Article  Google Scholar 

  13. Riahi, K. et al. The Shared Socioeconomic Pathways and their energy, land use, and greenhouse gas emissions implications: an overview. Glob. Environ. Change 42, 153–168 (2017).

    Article  Google Scholar 

  14. Hausfather, Z. & Peters, G. P. Emissions—the ‘business as usual’ story is misleading. Nature 577, 618–620 (2020).

    Article  CAS  Google Scholar 

  15. Rennert, K. et al. The social cost of carbon: advances in long-term probabilistic projections of population, GDP, emissions, and discount rates. Brook. Pap. Econ. Act. 2021, 223–305 (2022).

    Article  Google Scholar 

  16. Srikrishnan, V., Guan, Y., Tol, R. S. J. & Keller, K. Probabilistic projections of baseline twenty-first century CO2 emissions using a simple calibrated integrated assessment model. Clim. Change 170, 37 (2022).

    Article  CAS  Google Scholar 

  17. Lamboll, R. D. et al. Assessing the size and uncertainty of remaining carbon budgets. Nat. Clim. Chang. 13, 1360–1367 (2023).

    Article  Google Scholar 

  18. Urban, N. M. & Keller, K. Probabilistic hindcasts and projections of the coupled climate, carbon cycle and Atlantic meridional overturning circulation system: a Bayesian fusion of century-scale observations with a simple model. Tellus A Dyn. Meteorol. Oceanogr. 62, 737–750 (2010).

    Article  Google Scholar 

  19. Kriegler, E. Imprecise probability analysis for integrated assessment of climate change. Ph.D. thesis, Universität Potsdam (2005).

  20. Wong, T. E. et al. BRICK v.0.2, a simple, accessible, and transparent model framework for climate and regional sea-level projections. Geosci. Model Dev. 10, 2741–2760 (2017).

    Article  Google Scholar 

  21. Wong, T. E. et al. MimiBRICK.jl: a Julia package for the BRICK model for sea-level change in the Mimi integrated modeling framework. J. Open Source Softw. 7, 4556 (2022).

    Article  Google Scholar 

  22. Pattyn, F. et al. The Greenland and Antarctic ice sheets under 1.5 °C global warming. Nat. Clim. Chang. 8, 1053–1061 (2018).

    Article  Google Scholar 

  23. Bassis, J. N. et al. Stability of ice shelves and ice cliffs in a changing climate. Annu. Rev. Earth Planet. Sci. 52, 221–247 (2024).

    Article  CAS  Google Scholar 

  24. Seroussi, H. et al. ISMIP6 Antarctica: a multi-model ensemble of the Antarctic ice sheet evolution over the 21st century. Cryosphere 14, 3033–3070 (2020).

    Article  Google Scholar 

  25. Wong, T. E., Bakker, A. M. R. & Keller, K. Impacts of Antarctic fast dynamics on sea-level projections and coastal flood defense. Clim. Change 144, 347–364 (2017).

    Article  CAS  Google Scholar 

  26. Helgeson, C., Srikrishnan, V., Keller, K. & Tuana, N. Why simpler computer simulation models can be epistemically better for informing decisions. Philos. Sci. 88, 213–233 (2021).

    Article  Google Scholar 

  27. Lee, B. S., Haran, M., Fuller, R. W., Pollard, D. & Keller, K. A fast particle- based approach for calibrating a 3-D model of the Antarctic ice sheet. Ann. Appl. Stat. 14, 605–634 (2020).

    Article  Google Scholar 

  28. Grinsted, A. et al. The transient sea level response to external forcing in CMIP6 models. Earths Future 10, e2022EF002696 (2022).

    Article  Google Scholar 

  29. Hermans, T. H. J. et al. Projecting global mean sea-level change using CMIP6 models. Geophys. Res. Lett. 48, e2020GL092064 (2021).

    Article  Google Scholar 

  30. Doss-Gollin, J. & Keller, K. A subjective Bayesian framework for synthesizing deep uncertainties in climate risk management. Earths Future 11, e2022EF003044 (2023).

    Article  Google Scholar 

  31. Owen, A. B. Sobol’ indices and Shapley value. SIAM/ASA J. Uncertain. Quantification 2, 245–251 (2014).

    Article  Google Scholar 

  32. Song, E., Nelson, B. L. & Staum, J. Shapley effects for global sensitivity analysis: Theory and computation. SIAM/ASA J. Uncertain. Quantif. 4, 1060–1083 (2016).

    Article  Google Scholar 

  33. Reed, P. M. et al. Addressing uncertainty in multisector dynamics research [book]. Zenodo https://doi.org/10.5281/zenodo.6110623 (2022).

  34. Hough, A. & Wong, T. E. Analysis of the evolution of parametric drivers of high-end sea-level hazards. Adv. Stat. Climatol., Meteorol. Oceanogr. 8, 117–134 (2021).

    Article  Google Scholar 

  35. Hermans, T. H. J. et al. The timing of decreasing coastal flood protection due to sea-level rise. Nat. Clim. Chang. 13, 359–366 (2023).

    Article  Google Scholar 

  36. Kopp, R. E. et al. Communicating future sea-level rise uncertainty and ambiguity to assessment users. Nat. Clim. Chang. 13, 648–660 (2023).

    Article  Google Scholar 

  37. Rockström, J. et al. A safe operating space for humanity. Nature 461, 472–475 (2009).

    Article  Google Scholar 

  38. Steffen, W. et al. Planetary boundaries: guiding human development on a changing planet. Science 347, 1259855 (2015).

    Article  Google Scholar 

  39. Errickson, F. C., Keller, K., Collins, W. D., Srikrishnan, V. & Anthoff, D. Equity is more important for the social cost of methane than climate uncertainty. Nature 592, 564–570 (2021).

    Article  CAS  Google Scholar 

  40. Slangen, A. B. A., Haasnoot, M. & Winter, G. Rethinking sea-level projections using families and timing differences. Earths Future 10, e2021EF002576 (2022).

    Article  Google Scholar 

  41. Tebaldi, C., Snyder, A. & Dorheim, K. STITCHES: creating new scenarios of climate model output by stitching together pieces of existing simulations. Earth Syst. Dyn. 13, 1557–1609 (2022).

    Article  Google Scholar 

  42. Haasnoot, M. et al. Adaptation to uncertain sea-level rise; how uncertainty in Antarctic mass-loss impacts the coastal adaptation strategy of the Netherlands. Environ. Res. Lett. 15, 034007 (2020).

    Article  Google Scholar 

  43. Kwadijk, J. C. J. et al. Using adaptation tipping points to prepare for climate change and sea level rise: a case study in the Netherlands. Wiley Interdiscip. Rev. Clim. Change 1, 729–740 (2010).

    Article  Google Scholar 

  44. Browning, M. et al. Net-zero CO2 by 2050 scenarios for the United States in the Energy Modeling Forum 37 study. Energy Clim. Change 4, 100104 (2023).

    Article  CAS  Google Scholar 

  45. Sanderson, B. M., O’Neill, B. C. & Tebaldi, C. What would it take to achieve the Paris temperature targets? Geophys. Res. Lett. 43, 7133–7142 (2016).

    Article  Google Scholar 

  46. Kriegler, E. et al. Pathways limiting warming to 1.5 °C: tale of turning around in no time? Philos. Trans. A Math. Phys. Eng. Sci. 376, 20160457 (2018).

    Google Scholar 

  47. Oppenheimer, M. et al. Sea Level Rise and Implications for Low-Lying Islands, Coasts and Communities 321–445 (Cambridge Univ. Press, 2019).

  48. IPCC. Summary for Policymakers 3–32 (Cambridge Univ. Press, 2021).

  49. Hausfather, Z. & Peters, G. P. RCP8.5 is a problematic scenario for near-term emissions. Proc. Natl Acad. Sci. USA 117, 27791–27792 (2020).

    Article  CAS  Google Scholar 

  50. Kraan, B. C. P. & Cooke, R. M. Uncertainty in compartmental models for hazardous materials—a case study. J. Hazard. Mater. 71, 253–268 (2000).

    Article  CAS  Google Scholar 

  51. Fuller, R. W., Wong, T. E. & Keller, K. Probabilistic inversion of expert assessments to inform projections about Antarctic ice sheet responses. PLoS One 12, e0190115 (2017).

    Article  Google Scholar 

  52. Vega-Westhoff, B., Sriver, R. L., Hartin, C. A., Wong, T. E. & Keller, K. Impacts of observational constraints related to sea level on estimates of climate sensitivity. Earth’s Future 7, 677–690 (2019).

    Article  Google Scholar 

  53. Meinshausen, M., Raper, S. C. B. & Wigley, T. M. L. 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).

    Article  CAS  Google Scholar 

  54. Shaffer, G. Formulation, calibration and validation of the DAIS model (version 1), a simple Antarctic ice sheet model sensitive to variations of sea level and ocean subsurface temperature. Geosci. Model Dev. 7, 1803–1818 (2014).

    Article  Google Scholar 

  55. Ruckert, K. L., Guan, Y., Bakker, A. M. R., Forest, C. E. & Keller, K. The effects of time-varying observation errors on semi-empirical sea-level projections. Clim. Change 140, 349–360 (2017).

    Article  Google Scholar 

  56. Bates, D. et al. JuliaStats/GLM.jl: v.1.9.0. Zenodo https://doi.org/10.5281/zenodo.8345558 (2023).

  57. Desgagne-Bouchard, J. et al. Evovest/EvoTrees.jl: v.0.16.7. Zenodo https://doi.org/10.5281/zenodo.10901502 (2024).

  58. Blaom, A. et al. MLJ: a Julia package for composable machine learning. J. Open Source Softw. 5, 2704 (2020).

    Article  Google Scholar 

  59. Hastie, T., Tibshirani, R. & Friedman, J. The Elements of Statistical Learning: Data Mining, Inference, and Prediction Springer Series in Statistics (Springer, 2001).

  60. Redell, N. ShapML.jl: a Julia package for interpretable machine learning with stochastic Shapley values. Github https://github.com/nredell/ShapML.jl (2020).

  61. Štrumbelj, E. & Kononenko, I. Explaining prediction models and individual predictions with feature contributions. Knowl. Inf. Syst. 41, 647–665 (2014).

    Article  Google Scholar 

  62. Wong, T. et al. Model output supporting MimiBRICK v.1.1.10. Zenodo https://doi.org/10.5281/zenodo.6461559 (2022).

  63. Srikrishnan, V., Wong, T., Rennels, L., & Errickson, F. Global mean sea-level projections from MimiBRICK forced by uncertain emissions trajectories. Zenodo https://doi.org/10.5281/zenodo.11397684 (2024).

  64. Srikrishnan, V., Wong, T., Rennels, L., & Errickson, F. Global mean sea-level projections from MimiBRICK forced by the Shared Socioeconomic Pathways. Zenodo https://doi.org/10.5281/zenodo.14346559 (2024).

  65. Srikrishnan, V., Wong, T., Rennels, L., & Errickson, F. Code in support of ‘The interplay of future emissions and geophysical uncertainties for sea-level rise’. Zenodo https://doi.org/10.5281/zenodo.16966571 (2025).

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Acknowledgements

The authors thank F. Lehner, R. Gupta, A. Pollack, R. Venturelli, B. Schmidt and J. Lamontagne for valuable inputs and discussions. C.D. and V.S. were partially funded by the College of Agricultural & Life Sciences, Cornell University, and V.S. was partially funded by the US Department of Energy, Office of Science, Biological and Environmental Research Program, Earth and Environmental Systems Modeling, MultiSector Dynamics as part of the multiprogramme, collaborative Integrated Coastal Modeling (ICoM) project. T.W. was supported in part by the National Science Foundation under award no. DMS-2213432. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the US Department of Energy or the National Science Foundation.

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C.D.: conceptualization, methodology, software, formal analysis, writing, visualization. L.R. and F.E.: software, methodology, writing. T.W.: software, methodology, writing, visualization. V.S.: conceptualization, methodology, software, writing, visualization, supervision, funding.

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Correspondence to Vivek Srikrishnan.

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Nature Climate Change thanks Robert Kopp and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Extended data

Extended Data Table 1 Shapley indices for individual parameters over time

Extended Data Fig. 1 Overview of CO2 emissions ensemble.

Distributions of CO2 emissions scenarios. The CMIP6 SSP-RCP scenarios are provided until 2100 for comparison. a. Probability density of cumulative CO2 emissions from 2022–2100 (GtCO2). b. Cumulative density of cumulative density of CO2 emissions in from 2022–2100 (GtCO2). c. Evolution of CO2 emissions (GtCO2/yr) trajectories by scenario. The median is represented by the solid line and the shaded regions are 90% projection intervals. d. Cumulative density of CO2 emissions in 2100 (GtCO2/yr).

Extended Data Fig. 2 Uncertainty Group Importance for Selected Years.

Group uncertainty importance for the baseline ensemble in 2050, 2060, 2075, and 2100.

Supplementary information

Supplementary Information

Supplementary Figures 1-9, Supplementary Tables 1-2

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Darnell, C., Rennels, L., Errickson, F. et al. The interplay of future emissions and geophysical uncertainties for projections of sea-level rise. Nat. Clim. Chang. (2025). https://doi.org/10.1038/s41558-025-02457-0

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