A scaling approach to project regional sea level rise and its uncertainties 1Potsdam Institute for Climate Impact Research (PIK) Telegraphenberg A26, 14412 Potsdam, Germany
23 Jan 2013
2Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA, USA
3Dept. Geoscience and Remote Sensing and TU Delft Climate Institute, Delft University of Technology, Delft, The Netherlands
Received: 17 April 2012 – Published in Earth Syst. Dynam. Discuss.: 23 April 2012 Abstract. Climate change causes global mean sea level to rise due to thermal expansion
of seawater and loss of land ice from mountain glaciers, ice caps and ice
sheets. Locally, sea level can strongly deviate from the global mean rise due
to changes in wind and ocean currents. In addition, gravitational adjustments
redistribute seawater away from shrinking ice masses. However, the land ice
contribution to sea level rise (SLR) remains very challenging to model, and
comprehensive regional sea level projections, which include appropriate
gravitational adjustments, are still a nascent field (Katsman et al., 2011; Slangen et al., 2011).
Here, we present an alternative approach to derive regional sea
level changes for a range of emission and land ice melt scenarios, combining
probabilistic forecasts of a simple climate model (MAGICC6) with the new
CMIP5 general circulation models.
Revised: 13 December 2012 – Accepted: 14 December 2012 – Published: 23 January 2013
The contribution from ice sheets varies considerably depending on the
assumptions for the ice sheet projections, and thus represents sizeable
uncertainties for future sea level rise. However, several consistent and
robust patterns emerge from our analysis: at low latitudes, especially in the
Indian Ocean and Western Pacific, sea level will likely rise more than the
global mean (mostly by 10–20%). Around the northeastern Atlantic and the
northeastern Pacific coasts, sea level will rise less than the global
average or, in some rare cases, even fall. In the northwestern Atlantic,
along the American coast, a strong dynamic sea level rise is counteracted by
gravitational depression due to Greenland ice melt; whether sea level will be
above- or below-average will depend on the relative contribution of these two
factors. Our regional sea level projections and the diagnosed uncertainties
provide an improved basis for coastal impact analysis and infrastructure
planning for adaptation to climate change.
Citation: Perrette, M., Landerer, F., Riva, R., Frieler, K., and Meinshausen, M.: A scaling approach to project regional sea level rise and its uncertainties, Earth Syst. Dynam., 4, 11-29, doi:10.5194/esd-4-11-2013, 2013.