Climate change and rising sea levels are on track to wipe out almost half of the world’s sandy beaches (specifically 49.5%) by 2100, almost 132,000 kilometers of coastline, assuming carbon emissions continue to rise. its current level, according to a new study published in the journal Nature Climate Change. At work, they used satellite imagery to track how beaches have changed over the past 30 years and ran computer simulations to see how global warming could affect coasts in the future by also considering natural processes such as wave erosion. and the underlying geology of a beach, as well as human factors, such as coastal building developments, dams … everything that can affect the health of a beach.
Even if humanity dramatically reduces global warming fossil fuel pollution, more than a third of the planet’s sandy shores could disappear as a result of coastal flooding caused by weather and human interference.
“What we found is that by the end of the century about half of the world’s beaches will experience erosion of more than 100 meters,” said Michalis Vousdoukas, a co-author of the work. “They are likely to be lost.”
The consequences
Sand erosion will endanger wildlife and could cause significant damage to coastal settlements that will no longer have buffer zones to serve as a protective shield against rising sea levels and storm surges. Furthermore, government measures to mitigate the damage are expected to become increasingly expensive and, in some cases, unsustainable.
Some countries will be more affected than others. Australia would be the first country on the list to be severely affected by coastal erosion in the next 80 years. The study predicts that the coast of southern Australia could lose 12,324 km of coastline. Iconic Australian beaches such as Gold Coast, Bondi or Manly, will be history. Canada will lose 9 577 km of beaches, Chile 5 471 km, Mexico 4 119 km, China 4 084 km, the United States 3 908 km, Argentina 3 668 km and Iran 3 654 km of beaches, according to the study.
But you don’t have to travel far to see the dire effects: in just 30 years, according to scientists at the European Commission’s Joint Research Center , erosion will have destroyed 36,097 km or 13.6% of the beaches . Researchers predict that the situation will worsen in the second half of the century, dragging another 95,061 km, more than 25% of the beaches on Earth.
Worst of all, this is not the worst scenario we can run into. They are optimistic estimates, which rely on international action to combat climate collapse ( RCP4.5 ) with global warming of approximately 3 ºC. In this scenario, the oceans will have “barely” risen 50 centimeters by 2100.
What does this change depend on?
The degree to which beaches are at risk depends on how much the average global temperatures increase by the year 2100. Thus, the higher the temperature increase will mean a higher rise in sea level and more violent storms in some regions, causing more beaches to become vanish beneath the waves.
Why are beaches important?
Beaches are valuable for fun or recreation, tourism, and wildlife, while providing a natural barrier that protects coastal communities from waves and storms.
Despite the fact that beaches are dynamic environments , which change naturally with the tide and respond to changes in sea level, scientists say that when man includes its development near the water, it interrupts the movement capacity of a beach and stops the natural processes that allow sand to replenish itself. Today, many of the beaches facing serious erosion problems are located in urbanized areas.
Referencia: Sandy coastlines under threat of erosion, Nature Climate Change (2020). DOI: 10.1038/s41558-020-0697-0 , https://nature.com/articles/s41558-020-0697-0
