A study revealed that one-third of the world's sandy beaches could disappear by 2050, and almost half of them could be extinct by the end of the century.
Researchers from the Joint Research Centre (JRC) - European Commission's science and knowledge service - confirmed that a substantial proportion of these coastlines are already eroding fast due to climate change.
"Beaches are the interface between ocean and land, and provide coastal protection from marine storms and cyclones," notes Michalis Vousdoukas, lead author of the study and oceanographer at the JRC.
"A total of 31 percent of the world's sandy beaches are located in low-elevation coastal areas with a population density exceeding 500 people per square kilometers."
"Several countries, including the Democratic Republic of the Congo, Gambia, Jersey, Suriname, Comoros, Guinea-Bissau, Pakistan, and Mayotte (France), could see 60 percent of their sandy coastlines affected by the end of the 21st century."
Researchers also underline that Australia emerges as the potentially most affected country, with between 11,400 and 14,800 kilometers of sandy beach coastline threatened by erosion.
Using an identical impact metric, Canada ranks second (6,426 and 14,425 kilometers), followed by Chile (5,042 and 6,659kilometers), Mexico (4,507 and 5,488 kilometers), China (4,300 and 5,440 kilometers), USA (3,945 and 5,530 kilometers), Russia (3,056 and 4,762 kilometers) and Argentina (2,948 and 3,739 kilometers).
"From past experience, we know that effective site-specific coastal planning can stabilize coastlines and mitigate beach erosion. The most prominent example is the Dutch coast," Vousdoukas and his team adds.
Blame Sea-Level Rise and Human Intervention
Scientists adopted conservative variables to project results.
Although most sandy beaches have widths below 50 meters, the JRC chose a 100-meter threshold for the current analysis.
"Apart from the high vulnerability to coastal hazards, several of these countries will likely experience relevant socioeconomic consequences, especially those who rely on sandy coastlines as major tourist attractions," the study stresses.
JRC took into account estimates of future sea-level rise, spatial variations of coastal morphology, ambient shoreline change trends, and future changes in meteorological drivers - for example, storm surge and waves.
Sea-level rise is responsible for between 73 and 77 percent of the global median shoreline change in 2050, and between 73 and 85 percent by the end of the 21st century.
Human intervention in the shoreline will also substantially impact the shape of the world's coastline.
"Many coastal systems have already lost their natural capacity to accommodate or recover from erosion, as the backshore is heavily occupied by human settlements," Michalis Vousdoukas concludes.
"Dams and human development have depleted terrestrial sediment supply which would naturally replenish the shore with new material."
On a positive note, JRC researchers believe that the reduction of greenhouse gas (GHG) emissions could prevent 40% of shoreline retreat.