SAN FRANCISCO — Economists forecast erosion from rising sea levels could cost California hundreds of millions of dollars in lost tourism and tax revenues as beaches shrink and buildings would have to be protected, according to a new report.
A study by San Francisco State University released Tuesday shows a surge in the Pacific Ocean because of climate change, and accompanying storms and erosion, would batter California’s shoreline, diminishing the appeal of coastal areas and threatening structures with flood damage.
The eroding beaches will also destroy scores of animal habitats, the report finds.
"More than 80 percent of Californians live in coastal communities, and California’s beaches support local economies and critical natural species," said Philip King, the study’s author and an economics professor at San Francisco State.
The study commissioned by the California Department of Boating and Waterways examined sea level projections at five beach communities.
As the authors note, coastal storms and beach erosion are a common event that have already shaped the geography of coastal environments. Yet, because sea levels are projected to rise and storms are expected to be more intense due to a warming planet, the effects over the next century are expected to be more significant than ever.
The study said because of the uncertainty of how much the sea will rise, the researchers used three different sea level studies and flood models to reach their conclusions.
"We used the best available science," King said. "We wanted to come up with something that could be used by local planners."
The San Francisco State study is the latest to predict major consequences for California due to rising seas. In 2009, in a report funded by three California agencies, the Pacific Institute determined that nearly half a million people, wetlands, ecosystems and infrastructure would be at risk. They estimated that average projections find that seas would rise 4 to 5 feet by 2100, causing $100 billion in damage.
One of the communities San Francisco State profiled was Venice Beach, which could lose up to $440 million in tourism and tax revenue if the Pacific Ocean rises 55 inches by 2100. The study found sea level rise could cause $52 million in flood damage to homes in the Venice Beach area, and nearly $39 million in habitat loses.
The new report also found Zuma Beach and Broad Beach in Malibu could lose up to $500 million in tourism spending, $28.5 million in damage to homes and more than $102 million in losses to habitat.
And San Francisco’s Ocean Beach could see $540 million in damage to land, buildings and infrastructure.
Naturally, the damage predicted at each beach community differs by its geography, economy and land use decisions made by local officials.
While building seawalls to help protect buildings from an encroaching sea has been one response, King said, in some cases, allowing coastline to retreat or bolstering beaches with plants or other nourishment could be more cost-effective.
"Sea level rise will send reverberations throughout local and state economies," King said.