Illustrative multi‐centennial projections of global mean sea‐level rise and their application

We produce projections of global mean sea-level rise to 2500 for low and medium emissions scenarios (Shared Socioeconomic Pathways SSP1-2.6 and SSP2-4.5) relative to 2020, based on extending and combining model ensemble data from current literature. We find that emissions have a large effect on sea-...

Full description

Bibliographic Details
Published in:Earth's Future
Main Authors: Turner, F.E., Malagon Santos, V., Edwards, T.L., Slangen, A.B.A., Nicholls, R.J., Le Cozannet, G., O’Neill, J.F., Adhikari, M.
Format: Article in Journal/Newspaper
Language:English
Published: 2023
Subjects:
Online Access:https://www.vliz.be/imisdocs/publications/08/395808.pdf
Description
Summary:We produce projections of global mean sea-level rise to 2500 for low and medium emissions scenarios (Shared Socioeconomic Pathways SSP1-2.6 and SSP2-4.5) relative to 2020, based on extending and combining model ensemble data from current literature. We find that emissions have a large effect on sea-level rise on these long timescales, with [5, 95]% intervals of [0.3, 4.3]m and [1.0, 7.6]m under SSP1-2.6 and SSP2-4.5 respectively, and a difference in the 95% quantile of 1.6m at 2300 and 3.3m at 2500 for the two scenarios. The largest and most uncertain component is the Antarctic ice sheet, projected to contribute 5%–95% intervals of [−0.1, 2.3]m by 2500 under SSP1-2.6 and [0.0, 3.8]m under SSP2-4.5. We discuss how the simple statistical extensions used here could be replaced with more physically based methods for more robust predictions. We show that, despite their uncertainties, current multi-centennial projections combined into multi-study projections as presented here can be used to avoid future “lock-ins” in terms of risk and adaptation needs to sea-level rise.