A new study has forecasted that a majority of beaches and cliffs in Southern California would be eroded by the end of the century, pointing to rising sea levels as the likely reason.

With “limited human intervention” and in sea level rise of 0.93 to 2 meters, almost 31 percent to 67 percent of these beaches could become “completely eroded” by 2100, warned researchers. The state’s iconic shoreline spans from Santa Barbara to San Diego.

The findings prove important given the natural and economic roles of such beaches.

Crucial Economic Feature

U.S. Geological Survey (USGS) geologist and study author Patrick Barnard said that these SoCal beaches are the first line of defense against coastal storm impacts. If humans do not intervene more strongly to counteract erosion, flooding will become more severe and common in many places.

“This study indicates that we will have to perform massive and costly interventions to preserve these beaches in the future under the erosive pressures of anticipated sea level rise, or risk losing many of the economic and protective benefits beaches provide,” he said in a statement.

For John Ainsworth, California Coastal Commission’s executive director, the prospect of losing the beaches is “frankly unacceptable” given their role as public parks and “economic heart and soul” of their coastal communities.

The 310-mile stretch of Southern California is home to almost 20 million people and includes some of the most sought-after real estate in the whole country, from Los Angeles’ low-lying Westside communities to Orange County’s suburban neighborhoods. State officials estimated that economic returns from coast-related activities reach $40 billion every year.

Losing the beaches is feared to impact not just tourism, but also expose homes and infrastructure to various forms of damage.

Sea Level Rise

The findings also offer a peek into the expected future rise in sea levels. The prospect of losing the beaches is not a matter of “if” the seas are rising — that is already seen to be happening, so it’s now a matter of “how much.”

According to earlier conservative estimates by a UN panel, the oceans would rise by a meter by the end of the 21st century, while newer data showed that the rapid melting of Antarctic ice may actually double the rate. Recently, Arctic sea ice levels plummeted to a record low of 5.57 million square miles.

Rising sea levels is already an issue in many coastal communities. Sections of the Gulf Coast as well as Atlantic seaboard, for instance, have risen in greater rates than along parts of the West Coast, the Union of Concerned Scientists said.

The problem becomes more pronounced as a lot of regional coasts have become urbanized, when the environment in these areas are “some of the most dynamic settings” and can experience significant changes, Barnard added.

In a new report, the World Meteorological Organization (WMO) warned that current climate is bringing the planet into “truly uncharted territory,” highlighted exceptional ocean heat and sea level rises coupled with very low sea ice.

It cited significant flooding that recently hit parts of the world, including extreme flooding in Louisiana and parts of southern U.S. region last August, with losses estimated at $10 billion.