GEOSCAN Search Results: Fastlink


TitleA high-end estimate of sea level rise for practitioners
Authorvan de Wal, R S WORCID logo; Nicholls, RORCID logo; Behar, DORCID logo; McInnes, KORCID logo; Stammer, DORCID logo; Lowe, J A; Church, J AORCID logo; DeConto, RORCID logo; Fettweis, XORCID logo; Goelzer, HORCID logo; Haasnoot, MORCID logo; Haigh, I DORCID logo; Hinkel, JORCID logo; Horton, B P; James, TORCID logo; Jenkins, AORCID logo; LeCozannet, GORCID logo; Levermann, AORCID logo; Lipscomb, W HORCID logo; Marzeion, BORCID logo; Pattyn, FORCID logo; Payne, A JORCID logo; Pfeffer, W T; Price, S FORCID logo; Seroussi, HORCID logo; Sun, SORCID logo; Veatch, WORCID logo; White, K
SourceEarth's Future vol. 10, issue 11, 2022 p. 1-24, Open Access logo Open Access
Alt SeriesNatural Resources Canada, Contribution Series 20210469
Mediapaper; on-line; digital
File formatpdf
Subjectsenvironmental geology; Nature and Environment; Science and Technology; sea level changes; sea level fluctuations; ice; climate; climate effects; Estimates; Decision making
Illustrationstables; schematic models
ProgramClimate Change Geoscience Coastal Infrastructure
Released2022 10 22
AbstractSea level rise (SLR) is a long-lasting consequence of climate change because global anthropogenic warming takes centuries to millennia to equilibrate for the deep ocean and ice sheets. SLR projections based on climate models support policy analysis, risk assessment and adaptation planning today, despite their large uncertainties. The central range of the SLR distribution is estimated by process-based models. However, risk-averse practitioners often require information about plausible future conditions that lie in the tails of the SLR distribution, which are poorly defined by existing models. Here, a community effort combining scientists and practitioners builds on a framework of discussing physical evidence to quantify highend global SLR for practitioners. The approach is complementary to the IPCC AR6 report and provides further physically plausible high-end scenarios. High-end estimates for the different SLR components are developed for two climate scenarios at two timescales. For global warming of +2°C in 2100 (RCP2.6/SSP1-2.6) relative to pre-industrial values our high-end global SLR estimates are up to 0.9 m in 2100 and 2.5 m in 2300. Similarly, for a (RCP8.5/SSP5-8.5), we estimate up to 1.6 m in 2100 and up to 10.4 m in 2300. The large and growing differences between the scenarios beyond 2100 emphasize the long-term benefits of mitigation. However, even a modest 2°C warming may cause multi-meter SLR on centennial time scales with profound consequences for coastal areas. Earlier high-end assessments focused on instability mechanisms in Antarctica, while here we emphasize the importance of the timing of ice shelf collapse around Antarctica. This is highly uncertain due to low understanding of the driving processes. Hence both process understanding and emission scenario control high-end SLR.
Summary(Plain Language Summary, not published)
Sea-level projections are produced by summing the contributions from a number of sources, including ocean warming, ice sheet and glacier melt, and a number of other smaller effects. Most of the contributions are relatively well understood and can be modelled with their uncertainties, but the future state of large ice sheets, especially in Antarctica, is less well known and introduces considerable uncertainty into estimates of the probable largest, or high-end, projections of global sea-level. This paper directly addresses this problem by considering the probable largest contributions from each of the sources, and provides an approach that can be updated in the future as additional information becomes available and understanding is improved. The results indicate that for a global warming level of +2K in 2100 relative to pre-industrial values the high-end global sea-level rise (SLR) estimates are up to 1.0 m in 2100 and 3 m in 2300. For +5K warming level by 2100 SLR up to 1.6 m and up to 11 m in 2300. These results indicate that there are strong benefits to robust mitigation of carbon emissions. Even under relatively strong carbon mitigation, however, global sea level is projected to continue to rise, in agreement with the recently released Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC).

Date modified: