Sea-level rise
The headlines on sea-level rise were generated from work from a variety of sources.
These include:
- Intergovernmental Panel on Climate Change Working Group 2 report, Impacts, adaptation and vulnerability, 2007.
- Research at the Met Office Hadley Centre.
- University of Southampton, Centre for Coastal Processes, Engineering and Management, School of Civil Engineering and Environment, part of the Tyndall Centre.
- Potsdam Institute for Climate Impacts Research.
The Met Office Hadley Centre has conducted a number of research studies looking at sea-level rise in the UK and Europe. This includes work done as part of the TE2100 project which looked at sea-level rise and the resilience of the Thames barrier.
In addition, the IPCC WG2 report has collated research about the impacts sea-level rise.
Finally, specific research was done by Prof. Robert Nicholls and Dr Sally Brown at Southampton University and Dr Jochen Hinkel at Potsdam Institute for Climate Impacts Research, looking at the affect on human populations of sea-level rise.
Number of additional people flooded - headline results
- Rising temperatures cause global sea-level rise due to thermal expansion of seawater and the melting of land-based ice, threatening coastal populations with increased flooding and submergence among other impacts.
- By 2050 - without further coastal adaptation under a 4 °C/0.48m sea-level rise -an additional 130 million people per year would be expected to be flooded due to extreme sea levels, 3/4 of them in Asia.
- By 2075 - without further coastal adaptation under a 4 °C/0.53m sea-level rise - it would be an additional 150 million people per year.
- By 2100 - without further coastal adaptation under a 4 °C/0.59m sea-level rise - it would be an additional 145 million people per year. The fall in the number of people from 2075 to 2100 reflects the socio-economic scenario under which global populations decline. In the regional effect is apparent from 2050 onwards as population peaks in 2050.
- For all time steps, small islands regions have the highest relative increase in flooding without adAaptation, compared to the base climate. However, economic analysis suggests that adaptation would be widespread in response to these changes. For example, building sea dikes can decrease those potentially flooded to less than one million additional people per year, at annual costs of US$27 to US$35 billion. (Note: Costs are in US dollars are reported at 1995 values).
Additional number of people flooded by region, year and level of rise
| GVA Regions | 2050/0.48 m | 2075/0.53 m | 2100/0.59 m |
|---|---|---|---|
| Africa Atlantic Ocean | 6135 | 6564 | 5866 |
| Africa Indian Ocean | 7884 | 8364 | 7353 |
| Asia Indian Ocean | 45385 | 55527 | 55074 |
| Atlantic Ocean Small | 67 | 112 | 100 |
| Baltic Sea coast | 350 | 430 | 475 |
| Central America Atlantic Ocean | 89 | 91 | 83 |
| Central America Pacific Ocean | 173 | 171 | 154 |
| Caribbean islands | 1097 | 1103 | 1013 |
| Coasts of the CIS | 706 | 844 | 959 |
| East Asia Coast | 24542 | 24610 | 22392 |
| Gulf States | 737 | 948 | 1105 |
| Indian Ocean Small Islands | 313 | 311 | 258 |
| North America Atlantic Ocean | 909 | 1701 | 2663 |
| North America Pacific Ocean | 851 | 1581 | 2223 |
| Northern Mediterranean | 650 | 748 | 953 |
| Non GVA | 398 | 1542 | 1531 |
| North and West European Coast | 560 | 822 | 1792 |
| Pacific Ocean large | 309 | 461 | 717 |
| Pacific Ocean small | 529 | 537 | 506 |
| South America Atlantic Ocean | 4600 | 6149 | 6681 |
| South America Pacific Ocean | 1511 | 1467 | 1266 |
| South East Asia Coast | 28753 | 32740 | 28165 |
| Southern Mediterranean | 3187 | 4315 | 4771 |
| Southern Atlantic Small islands | 0 | 0 | 0 |
| Global sum | 129734 | 151136 | 146100 |
Numbers were based on extreme sea levels under a 4 degree rise in temperature and the A1B socio-economic scenario. Research was undertaken by Dr Sally Brown and Prof. Robert J Nicholls(School of Civil Engineering and the Environment, University of Southampton, UK), Dr Jason Lowe (Met Office) and Dr Jochen Hinkel ( Potsdam Institute for Climate Impact Research)
These results are based on QUEST-GSI research. Sea-level data is from the A1B ensemble mean MAGICC scenario. Prescribed datasets have been made based on 0.5°C-4.0°C increase in 2050 at 0.5°C increments. The number of people additionally flooded due to storm surges is modelled using DIVA (McFadden et al. 2007; Vafeidis et al. 2008) which combines sea-level and socio-economic scenarios.
Data is reported in GVA regions, example of a map below.
References
Brown, S. et al. (2009). Sea level response and impacts of a 1°C to 7°C prescribed temperature rise by 2100. 4 degrees and beyond. International climate conference, Oxford, UK. September 2009.
Gregory J.M. and P. Huybrechts, 2006: Ice-sheet contributions to future sea-level change. Phil Trans R. Soc A, 364,1709-1731.
Lowe, J.A., and J.M. Gregory, 2005: The effects of climate change on storm surges around the United Kingdom. Phil. Trans. R. Soc A, 363, 1313-1328.
McFadden, L., R.J. Nicholls, A. Vafeidis and R.S.J. Tol, 2007: A methodology for modelling coastal space for global assessment. Journal of Coastal Research, 23, (4), 911-920.
Ministry of Natural Resources and Environment, 2009: Climate change, sea level rise scenarios for Vietnam .
Nicholls, R.J. and A. Cazenave, 2010: Sea-Level Rise and Its Impact on Coastal Zones. Science, 328, 1517-1520.
Nicholls, R.J., and R.J.T. Klein, 2005: Climate change and coastal management on Europe's coast. Managing European Coasts: Past, Present and Future, J.E. Vermaat, L. Vouwer, K. Turner and W. Salomons, Eds., Springer, Environmental Science Monograph Serices. 199-226.
Nicholls, R.J., N. Marinova, J.A. Lowe, S. Brown, P. Vellinga, D. de Gusmao, J. Hinkel, and R.S.J. Tol, 2011: Sea-level rise and its possible impacts given a 'beyond 4 ºC world' in the twenty-first century. Phil. Trans. R. Soc A, 369, 161-181.
Ridley J, J.M. Gregory, P. Huybrechts and J. Lowe, 2009: Thresholds for irreversible decline of the Greenland ice sheet. Climate Dynamics 35, Number 6, 1049-1057, DOI: 10.1007/s00382-009-0646-0.
Phienwej, N. and P. Nutalaya, 2005: Subsidence and Flooding in Bangkok. In: Gupta, A. (ed.) The Physical Geography of Southeast Asia. Oxford University Press, 358-379 pp.
Vafeidis, A.T., R. J. Nicholls, L. McFadden, R. S. J. Tol, J. Hinkel, T. Spencer, P.S. Grashoff, G.Boot, and R.J. T. Klein, 2008: A new global coastal database for impact and vulnerability analysis to sea-level rise. Journal of Coastal Research, 24, 917-924.
Vaughan DG, 2008: West Antarctic Ice Sheet collapse - the fall and rise of a paradigm. Climatic Change, 91, 65-79, DOI 10.1007/s10584-008-9448-3.
