Sea level rise and hydrological problems of coastal zones:
IPCC estimates a sea level rise of 8 to 88 cm by the year 2100 due to global warming. Further impacts on the coastal zone result from regional tectonic subsidence, shore erosion, changes in freshwater discharge and intensified cyclones. Increased precipitation will enhance river floods and threaten coastal cities and densely populated deltas, e.g. London, Bangkok and the Ganges/Brahmaputra and Mekong deltas.
As about 50% of the world’s population live within coastal areas, their ecological functions, stability and benefits are rapidly deteriorating under anthropogenic pressure and climate change. Vulnerability assessments according to a Common Methodology proposed by IPCC are now being replaced by highly integrated regional risk assessments including natural and social sciences and public risk communication.
Examples are given for the German island of Sylt and the Weser estuary region, for which the adaptation capacity is estimated as high, whereas in many coastal regions and islands outside Europe and North America adaptation will pose huge problems.