Sea-level rise and impacts projections under a future scenario with large greenhouse gas emission reductions
Sea-level rise and impacts projections under a future scenario with large greenhouse gas emission reductions
Using projections from two coupled climate models (HadCM3C and HadGEM2-AO), we consider the effect on 21st century sea-level rise (SLR) of mitigation policies relative to a scenario of business-as-usual (BAU). Around a third of the global-mean SLR over the century is avoided by a mitigation scenario under which global-mean near surface air temperature stabilises close to the Copenhagen Accord limit of a 2°C increase. Under BAU (a variant of the A1B scenario) the model-averaged projected SLR for 2090–2099 relative to 1980–1999 is 0.29 m–0.51 m (5%–95% uncertainties from treatment of land-based ice melt); under mitigation (E1 scenario) it is 0.17 m–0.34 m. This reduction is primarily from reduced thermal expansion. The spatial patterns of regional SLR are fairly dissimilar between the models, but are qualitatively similar across scenarios for a particular model. An impacts model suggests that by the end of the 21st century and without upgrade in defences around 55% of the 84 million additional people flooded per year globally under BAU (from SLR alone) could be avoided under such mitigation. The above projections of SLR follow the methodology of the IPCC Fourth Assessment. We have, however, also conducted a sensitivity study of SLR and its impacts where the possibility of accelerated ice sheet dynamics is accounted for
L12604-[5]
Pardaens, A.K.
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Lowe, J.A
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Brown, S.
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Nicholls, R.J.
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de Gusmão, D.
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23 June 2011
Pardaens, A.K.
93a849ae-52ab-4bb1-ad74-0c154f280f60
Lowe, J.A
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Brown, S.
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Nicholls, R.J.
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de Gusmão, D.
27138f93-8cec-403e-962e-ba1b00b13fc8
Pardaens, A.K., Lowe, J.A, Brown, S., Nicholls, R.J. and de Gusmão, D.
(2011)
Sea-level rise and impacts projections under a future scenario with large greenhouse gas emission reductions.
Geophysical Research Letters, 38 (12), .
(doi:10.1029/2011GL047678).
Abstract
Using projections from two coupled climate models (HadCM3C and HadGEM2-AO), we consider the effect on 21st century sea-level rise (SLR) of mitigation policies relative to a scenario of business-as-usual (BAU). Around a third of the global-mean SLR over the century is avoided by a mitigation scenario under which global-mean near surface air temperature stabilises close to the Copenhagen Accord limit of a 2°C increase. Under BAU (a variant of the A1B scenario) the model-averaged projected SLR for 2090–2099 relative to 1980–1999 is 0.29 m–0.51 m (5%–95% uncertainties from treatment of land-based ice melt); under mitigation (E1 scenario) it is 0.17 m–0.34 m. This reduction is primarily from reduced thermal expansion. The spatial patterns of regional SLR are fairly dissimilar between the models, but are qualitatively similar across scenarios for a particular model. An impacts model suggests that by the end of the 21st century and without upgrade in defences around 55% of the 84 million additional people flooded per year globally under BAU (from SLR alone) could be avoided under such mitigation. The above projections of SLR follow the methodology of the IPCC Fourth Assessment. We have, however, also conducted a sensitivity study of SLR and its impacts where the possibility of accelerated ice sheet dynamics is accounted for
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2011GL047678.pdf
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Published date: 23 June 2011
Organisations:
Energy & Climate Change Group
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Local EPrints ID: 197915
URI: http://eprints.soton.ac.uk/id/eprint/197915
ISSN: 0094-8276
PURE UUID: eae81b50-c98f-479c-b677-4821433ffae6
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Date deposited: 29 Sep 2011 07:49
Last modified: 15 Mar 2024 03:31
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A.K. Pardaens
Author:
J.A Lowe
Author:
D. de Gusmão
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