LOS ANGELES, June 20 -- Recent reports of U.S. coastline homes on the brink of collapsing into the ocean have thrust the issue of coastal erosion into the national spotlight, particularly in California, where the economic implications are dire.

Unprecedented storms early this year have exposed the vulnerability of California's coastline, with several multi-million-dollar homes in Orange County precariously hanging off the cliffside. The dramatic images, as documented by local television channels, are not isolated incidents.

Coastal landslides and ground movement made headlines in February as the Wayfarers Chapel in Rancho Palos Verdes, one of only a handful of National Historic Landmarks in Southern California, was forced to shutter its doors due to landslides. The iconic glass chapel overlooking the ocean is reportedly set to be dismantled and stored until a new site is determined for it to be rebuilt. During an unexpectedly wet winter earlier this year, the coastal city Rancho Palos Verdes, located in south Los Angeles County, experienced an unprecedented landslide, which has claimed dozens of homes.

"The land beneath our chapel is moving up to 7 inches per week," an employee of the chapel told Xinhua on Wednesday, noting the effects of climate change.

Scientists point to a combination of factors driving coastal erosion, including climate change-induced sea level rise and urban development along the shores.

A new study by the University of Southern California (USC) provides concrete data, underscoring the rapid acceleration of coastal erosion in California.

Published in the environmental science journal Communications Earth and Environment last month, the researchers project that the cost of living on the coast in Southern California could be five times more expensive by 2050 due to escalating beach erosion.

The study forecasts a significant acceleration in shoreline retreat, with sandy beaches losing sand at an alarming rate. The shoreline for sandy beaches is expected to retreat from 1.45 meters per year currently to 2.12 meters by 2050, and even more drastically to 3.18 meters per year by 2100.

This will require far more frequent and expensive beach nourishment projects -- the process of replenishing eroded beaches with sand to bolster them against waves and storms.

The USC researchers estimate the annual volume of sand required for beach nourishment could triple by 2050, and the associated cost for this nourishment will grow five times.

This will be a costly endeavor, "exacerbating several coastal communities' economic and logistical pressures," said the researchers in the study.

The study highlights that coastal erosion in California is driven by changes in precipitation patterns and urban development, suggesting that the coastal problems often start inland due to the rapid growth of cities along the coast.

Supporting these concerns, another recent study led by a U.S. Geological Survey scientist estimated that between 24 percent to 75 percent of California's beaches could be completely eroded by 2100 after analyzing decades of satellite imagery, sea level projections, and global wave patterns.

The economic consequences of this erosion are far-reaching. The California Legislative Analyst's Office in a 2020 report echoed these fears, noting the potential for increased flooding and erosion of beaches and cliffs.

The office estimated that 8 to 10 billion U.S. dollars of existing property in California will likely be underwater by 2050, with an additional 6 to 10 billion dollars at risk during high tides.

This crisis is not limited to California. The National Oceanic and Atmospheric Administration (NOAA) forecast in a 2022 report that the sea level along the U.S. coastline would increase 25 to 30 centimeters by 2050, which would be as much as the rise measured over the last 100 years. The agency also warned that this increase would lead to more frequent and damaging flooding by 2050 -- more than 10 times as often as it does today.

Nearly 40 percent of the U.S. population, or 127 million people, live in counties on the coast, said NOAA, and this coast erosion not only put these people at risk but also, threaten "the outsize U.S. marine economy" which is fueled by tourism and recreation, offshore energy, shipbuilding, and aquaculture, said NOAA.

  - Xinhua