An international team of coastal scientists has dismissed suggestions that half the world’s beaches could become extinct over the course of the 21st century. As long as beaches have room to move, they can retain their overall shape.
A new report has concluded that there is potential for beaches to migrate landwards as sea level rises and shorelines retreat.
The key notion behind the theory is that if beaches have space to move into under the influence of rising sea levels – referred to as accommodation space – they will retain their overall shape and form but in a more landward position, explains a statement.
The new research says that beaches backed by hard coastal cliffs and engineering structures, such as seawalls, are indeed likely to disappear in the future due to sea-level rise as these beaches are unable to migrate landward. They will first experience ‘coastal squeeze’ resulting in a decrease in width, and will eventually drown.
However, beaches backed by low-lying coastal plains, shallow lagoons, salt marshes and dunes will migrate landward as a result of rising sea level. In these cases, the shoreline will retreat, but the beaches are still likely to remain, albeit a little raised in elevation and located landward, and will certainly not go ‘extinct’.
The new paper says there is currently no information available globally on the number of beaches which fall into either category and, as such, it is impossible to quantify what proportion of the world’s beaches will disappear between now and 2100.
Image: Norbert Rupp/ Flickr Creative Commons