Enriquesnush (Ziyaretçi)
| | Half of the world's beaches could disappear by 2100 because of severe erosion linked to climate change, a study published Monday suggests.
The main causes are sea-level rise and erosion from storms, the study says, which warned of "the near-extinction of almost half of the world's sandy beaches by the end of the century."
Beaches in the United States will be "greatly affected," as will shorelines in Canada, Mexico, China and Chile. In the U.S., beaches along the East Coast and the Gulf Coast will experience the most erosion, lead author Michalis Vousdoukas said in an e-mail to USA TODAY.
Vousdoukas, of the European Unions Joint Research Center in Ispra, Italy, and other researchers used satellite images to track the way beaches have changed over the past 30 years and simulated how global warming might affect them in the future.
The study found that West Africa will see some of the worst losses, where more than 60% of sandy coastline may be lost in countries such as The Gambia and Guinea-Bissau.
Australia will also take a hit: When the total length of sandy beach projected to be lost is analyzed, Australia would be hit the hardest, with more than 7,000 miles at risk.
Beaches are valuable for recreation, tourism and wildlife while also providing a natural barrier that protects coastal communities from waves and storms.
The projected shoreline changes will substantially impact the shape of the worlds coastline, more than a third of which is sandy beach, the authors write.
Sea-level rise is the dominant cause of the predicted loss of the world's beaches, especially in eastern North America, Vousdoukas said.
"Sea level has been increasing at an accelerated rate during the past 25 years and will continue to do so with climate change," the study says. "There is a clear cause-and-effect relationship between increasing sea levels and shoreline retreat, pointing to increased coastal erosion issues."
Andres Payo, an expert on coastal hazards and resilience at the British Geological Survey, who wasn't involved in the study, said that while the studys methods are sound, its claims should be treated with caution.
There are many assumptions and generalizations that could change the outcome of the analysis both qualitatively and quantitatively, Payo said.
The studys authors calculate that up to 40% of shoreline retreat could be prevented by reducing the greenhouse gas emissions that are driving climate change but say large and growing populations living along the coast will need to be protected through other measures.
Citing the example of the Netherlands, which has battled the sea for centuries and even reclaimed substantial areas of low-lying land, the authors say that past experience has shown that effective site-specific coastal planning can mitigate beach erosion, eventually resulting in a stable coastline. |
