SAN FRANCISCO - 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)

 

Copyright 2011  Reuters Environmental Online Report