North Sea storm surge statistics based on projections in a warmer climate: How important are the driving GCM and the chosen emission scenario?

Abstract

Climate models, simulating the effect of plausible future emission concentrations (scenarios), describe for the future an increase of high wind speeds over Northwest Europe during winter. With the help of a hydrodynamic model of the North Sea, these atmospheric future conditions are used to project storm surge heights for the Northwest European Shelf Sea. Four different projections are presented, all generated with the same Regional Climate Model, which itself is driven with two different Global Climate Model scenarios both exposed to two different emission scenarios. The analyses are carried out for a 30-year time-slice at the end of the 21st century. All four ensemble members point to a significant increase of storm surge elevations for the continental North Sea coast of between 15 and almost 25 cm. However, the different storm surge projections are not statistically distinguishable from each other but can provide a range of possible evolutions of surge extremes in a warmer climate. Copyright 2005 by the American Geophysical Union.