Rising sea levels could take economic toll on California beaches

A state-commissioned study by San Francisco State says erosion and storm damage by the advancing ocean over the next century could cut into tourism and tax revenue.
Tony Barboza, Los Angeles Times 14 Sep 11;

As rising sea levels eat away at the California coastline over the next century, the advancing ocean could cause hundreds of millions of dollars in damage to beach communities as tourism and tax revenue is swept away, according to a state-commissioned study released Tuesday.

As climate change warms and expands the ocean, increased storm damage and erosion will narrow the state's beaches and diminish their appeal to both tourists and wildlife, economists at San Francisco State predict.

"You need a certain amount of space for people to recreate, and, as beaches erode, you lose beach size and you lose tourism," said study author Phillip King, associate professor of economics at San Francisco State.

The study, commissioned by the California Department of Boating and Waterways, looked at five California beach communities, using sea-level-rise projections to estimate economic losses from flooding and beach erosion.

Venice Beach, for instance, could lose up to $440 million in tourism and tax revenue if the Pacific Ocean rises 55 inches by 2100, as scientists predict.

A drop-off in visitors to an eroded Zuma Beach and Broad Beach in Malibu would cost as much as $500 million in tourism spending and tax revenue, the study found.

The effect of more destructive storm surges and higher tides would reverberate through the local and state economy, researchers said.

The ocean's expansion would be particularly hard on Southern California, where the heavily used shoreline generates big bucks to businesses, which pass some of it on to local governments in taxes.

Elsewhere in the state, homes and roads would be particularly vulnerable.

At San Francisco's Ocean Beach, the increasingly erosive power of storm surges could cause $540 million in damage to land, buildings and infrastructure by century's end, researchers project.

The study also examined beaches at Torrey Pines in San Diego County and Carpinteria in Santa Barbara County.

The research underscores the pressing need for beach communities to adapt to the rising waters by building sea walls, replenishing beach sand or pushing homes and structures away from the shoreline, King said.

"Sea-level rise is here," King said, "and we need to start planning for it."

The ocean has risen about 8 inches in the last century and is expected to swell at an increasing rate with global warming.

But California may have been spared the full strength of the ocean's advance for the last few decades, recent research suggests.

Earlier this year, scientists at Scripps Institution of Oceanography at UC San Diego found that while sea levels rose around the globe, they were on hiatus on the U.S. West Coast for the last three decades because of a pattern of cold surface waters.

But that trend may be reversing, the study found, and an era of accelerated sea-level rise could begin this decade.

Rising Seas Expected To Wash Out Key California Beaches
Emmett Berg PlanetArk 16 Sep 11;

Rising seas forecast from climate change will likely wash away some of California's most iconic beaches by century's end, along with hundreds of millions of dollars in real estate, roads and tax revenues, a new study found on Wednesday.

"If beaches disappear, shrink and erode, we are going to have less tourism," said Phillip King, associate professor of economics at San Francisco State University. "We took the best available science, and it's possible the (estimated) costs are still too low."

With a grant from the state Department of Boating and Waterways, university economists spent two years projecting economic losses several coastal California communities could expect from climate change linked to growing concentrations of heat-trapping "greenhouse" gases in the atmosphere.

The five stretches of coastline under scrutiny were San Francisco's Ocean Beach, as well as the Southern California beach communities of Carpinteria, Malibu, Venice and Torrey Pines State Reserve near San Diego.

Based on forecasts calling for sea levels to rise between 1 and 2 meters by the year 2100, researchers devised models predicting which properties, infrastructure, wildlife habitat and open space would be flooded or eroded, and the value of those losses.

They also surveyed existing reports to determine how costly it would be to protect or replace those coastal resources.

Venice Beach stands to be the hardest hit of the five shorelines studied, with a 2-meter rise in sea level over the next 90 years resulting in $96 million in identified losses, according to the report. A 1-meter increase over the same period would trigger $31.6 million in losses there.

Factoring in additional damage from erosion of areas just inland from the coastline, the study predicted total economic losses by century's end ranging from nearly $600 million to $1 billion or more for the five areas combined.

A more comprehensive 2009 study by the Pacific Institute, an environmental think tank, concluded that nearly 500,000 people and $100 billion worth of property along California's entire coast were at risk of facing severe flooding from rising sea levels this century unless new safeguards were put in place.

That report also found that large tracts of the picturesque Pacific coast would be lost to accelerated erosion.

It suggested that the heightened flood risk could be minimized by investing about $14 billion in a system of newly built or upgraded sea walls, levees and offshore breakwaters to reinforce some 1,100 miles of coast.

The San Francisco State University researchers make no explicit recommendations but said their findings could guide policymakers when they consider future shorefront development, King said.

(Editing by Steve Gorman and Cynthia Johnston)