Population growth is on the rise in coastal regions, in particular in the economically attractive areas around the mouths of rivers. Over the course of climate change, however, the dangers posed to coastal inhabitants by the ocean have increased. In future, coasts will be more exposed than to date to natural hazards such as storms, floods, salination of ground water, coastal erosion, tsunamis, as well as the global rise in sea levels. For example, over the past 100 years, the sea level has risen by almost twenty centimetres (2 mm/year). Recent calculations based on models predict far higher rates of rise for the coming centuries due to global warming.
Coastal regions are highly sensitive to any changes caused by the sea and react immediately. Sediments in shallow waters and on land are used by scientists as an "archive" for information on earlier changes in water flow (hydrodynamics), in the morphology of the seafloor and the sea level. The sediments also provide a record of when extreme events such as storms, changes in the ground water and tsunamis have taken place. Comparisons of these "archives" (on a scale of years to centuries) with current processes in coastal change permit better predictions on the future development of coastal systems, with regard to their particular risk potential.
The dangers posed by climate change to the Earth's coasts also entail social, cultural, economic and ecological risks. They directly affect the population and the areas they inhabit, as well as the regional and national economic resources (e.g., tourism infrastructure). A comprehensive and effective risk management must be put in place for coastal regions, as these dangers have increased, e.g., storms with higher wind velocities create higher tides on the coasts.