Heavy surf from Hurricane Sandy crashes on to the sand. All beaches with defences ... are in danger. When you build the sea wall, that is the end of the beach. Photograph: Mark Wilson/Getty Images

The worlds beaches are being washed away as coastal developments increase in size and engineers build ever higher sea walls to defend against fierce winter storms and rising sea levels, according to two of the worlds leading marine geologists.

The warning comes as violent Atlantic and Pacific storms this week sent massive 50ft waves crashing over sea defences, washed away beaches and destroyed concrete walls in Europe, north America and the Philippines.

Most natural sand beaches are disappearing, due partly to rising sea levels and increased storm action, but also to massive erosion caused by the human development of the shore, said Andrew Cooper, professor of coastal studies at the University of Ulster.

The widespread damage on western Europes storm-battered shores, the devastation caused by hurricane Sandy along the northeastern US seaboard, the deaths brought on by typhoon Haiyan in the Philippines all exemplify the total inadequacy of [coastal] infrastructure and the vulnerability of cities built on the edge of coastlines, said Orrin Pilkey, professor of earth and ocean sciences at Duke University in Durham, North Carolina.

Pilkey and Cooper say in a new book, The Last Beach, that sea walls, which are widely believed by many local authorities to protect developments from erosion and sea level rise, in fact lead to the destruction of beaches and sea defences and require constant rebuilding at increasing cost.

Dunes and wide beaches protect buildings from storms far better than sea walls, say the authors. The beach is a wonderful, free natural defence against the forces of the ocean. Beaches absorb the power of the ocean waves reducing them to a gentle swash that laps on the shoreline. Storms do not destroy beaches. They change their shape and location, moving sand around to maximise the absorption of wave energy and then recover in the days, months and years to follow, said Pilkey .

Beaches in nature are almost indestructible, but seawall construction disrupts the natural movement of sand and waves, hindering the process of sand deposition along the shorelines, said Cooper.

The wall itself is the problem. If you build a sea wall to protect the shore, the inevitable consequence is that the beach will disappear. The wall cannot absorb the energy of the sea. All beaches with defences ... are in danger. When you build the sea wall, that is the end of the beach, he said.

Beaches have become long, narrow engineering projects sustained only by constant maintenance and ongoing expenditures. Ugly seawalls have removed beaches altogether. Trying to hold the shoreline in position makes a flexible response to sea level rise more difficult, said Pilkey.

Visit link:

World's beaches being washed away due to coastal development