The vulnerability of the Mediterranean coastal areas in response to the sea level dynamics: a short review of causes, effects and open questions

Abstract

The entire world's coastal area is now directly affected by global warming. A significant portion of the world's population lives in the Mediterranean basin and exerts profound direct human pressure on the coasts and on the river basins. River management plans, residential and industrial structures, and coastal protection projects result in the loss of a large portion of the sediments that rivers release to the sea, together with the continued and extensive use of the coastal areas. This entails a negative sedimentary budget and reduced resilience of the mobile coastal systems. Moreover, the rise in eustatic sea levels resulting from melting glaciers threatens coastal areas characterized by low rocky coasts and coastal plains. The negative vertical movements of coastal areas amplify this effect on the low-lying areas with a significant regional and local contribution, often linked to human activities. The warming of the sea and the release of thermal energy generate intense marine weather phenomena known as "medicanes", whose impact on the coastal zone leads to frequent flooding. The possible tsunami impacts could be not thwarted by the coastal landscape which is in evident and continuous degradation. The combination of sea level rise, paroxysmal weather processes and human activity amplify erosional processes and reduces the ability of coastal systems to adapt to new conditions; this increases the vulnerability of coastal plains, inducing more and more real risk situations.