Up to 70% of California’s beaches could disappear by the end of the century due to rising sea levels

Vast stretches of California’s beaches could be lost to climate change, a recent paper predicted, with 25-70 percent of the state’s beaches eroded completely by the end of this century.

The study, published in Marchwas prepared by five scientists from the USGS Pacific Coastal & Marine Science Center, the University of Illinois at Chicago and the University of New South Wales – Sydney.

The five looked at Ocean Beach in San Francisco and studied satellite images of the beach over two decades.

They then took the entirety of California’s 1,100-mile coastline and used their models to predict how climate change would affect beaches, using a predicted sea level rise of 5 to 10 feet over the next 80 years.

They found that 25-70 percent of the state’s beaches could be lost.

Newport Beach, just south of Los Angeles, is also considered at risk, as research predicts that 25-70 percent of California’s beaches could be eroded by rising sea levels

“By 2100, the model estimates that 25-70 percent of California’s beaches could be completely eroded due to sea-level rise scenarios of 0.5 to 3.0 m, respectively,” the authors wrote.

“The modeling system presented here that is based on satellite data is generally applicable to a variety of coastal regions around the world due to the global coverage of satellite imagery.”

The authors warned that several well-known beaches were in danger — including Point Arena and Humboldt Bay in Northern California; Pismo Beach and Morro Bay in Central California; and Newport Beach and San Clemente in Southern California.

The study, quoted by the news website SFGatehas yet to be peer-reviewed.

It follows a similar study in 2017, by the same group of researchers, who found that 31 to 67 percent of Southern California beaches were at risk of destruction.

“The model predictions, while subject to considerable uncertainty, indicate that significant coastline impacts could occur due to accelerated sea level rise,” the authors conclude.

It is likely that many California beaches will require substantial management efforts (e.g., beach nourishment, sand retention, armoring, dune restoration, and other engineering and wildlife-based solutions) to preserve existing beach widths and the many services they provide. provided.’

San Clemente, another beach in the Los Angeles area, will be vulnerable for the next 80 years, the researchers conclude in a study yet to be peer-reviewed

Morro Bay, 200 miles north of Los Angeles, is threatened by rising sea levels, the team said

Experts are very concerned about rising sea levels, but do not agree on the predicted rise.

The National Oceanic and Atmospheric Administration predicted last year that sea levels in California and along the West Coast would rise by up to eight inches over the next 25 years.

Mark Merrifield, a coastal oceanographer at Scripps Institution of Oceanography in La Jolla, shared The protector the satellite models used by the five researchers should be taken with some skepticism because they were new.

“Beach morphology models generally have limited ability to predict present-day changes, few datasets are available for validation of the methodology, and projections of future wave and water levels introduce another level of uncertainty,” he said.

But Sean Vitousek, the lead author of both studies, said they proved that action needs to be taken now, even though people disagreed on the exact magnitude.

“Beaches are perhaps California’s most iconic feature, and the potential to lose this identity is real,” he wrote in 2017.

The effect of California’s loss of beaches is not just a matter of impacting the tourism economy.

“The loss of the protective strip of beach sand between us and the pounding surf exposes critical infrastructure, businesses and homes to damage.”