Rising seas pose threat
Experts warn if problem persists, surges will impact the state’s coastal area, Delta
A slow-moving emergency is lapping at California’s shores — climate-driven sea-level rise that experts now predict could elevate the water in coastal areas up to 10 feet in just 70 years, gobbling up beach front and overwhelming low-lying cities.
The speed with which polar ice is melting and glacier shelves are cracking off indicates to some scientists that once-unthinkable outer-range projections of sea rise may turn out to be too conservative. A knee-buckling new state-commissioned report warns that if nothing changes, California’s coastal waters will rise at a rate 30 to 40 times faster than in the last century.
The potential result: crippled economies, compromised public safety, submerged infrastructure, and a forced retreat from
our iconic Pacific coast.
No state has done more than California to curb greenhouse gas emissions that contribute to climate change and sea-level rise. But experts say that even if carbon reductions continue, residual warming of the ocean will continue unchecked, breeding surges that will impact the state’s coast and the Sacramento-San Joaquin River Delta.
Last month the U.S. Geological Survey estimated that without concerted intervention, as much as 67 percent of Southern California’s beaches could be lost to rising seas by the end of the century.
A consensus of scientific research makes catastrophic projections that, in the worst case, will be reality by the end of this century:
San Francisco and n Oakland international airports will face flooding, rendering them unusable.
Housing perched on n fast-eroding coastal bluffs in Pacifica and elsewhere will continue to crash into the sea.
Malibu’s Broad Beach n will dwindle into a seldomseen slice of sand, its name an oxymoron.
Flooding in the Delta n will overwhelm rivers and strain levees critical to California’s water supply.
Power plants, nuclear n waste sites and other sensitive waterside sites need to be fortified or lost.
Roads, bridges and n railways along the coast from Mendocino to San Diego will be abandoned and relocated inland.
San Francisco’s Embarcadero n and low-lying cities such as Huntington Beach will flood more frequently and more severely.
More than 42,000 n homes in California will be under water — not merely flooded, but with seawater over roofs.
The grim outlook is mirrored in the latest report, which the state’s Ocean Protection Council formally adopted on Wednesday. The report’s sea-level rise projections will assist state agencies and local governments with planning.
No stretch of the state’s 3,400 miles of coast, bays, inlets and islands will be spared. Addressing sealevel rise will cost a staggering amount of public and private money, and will particularly impact the poor and vulnerable. The problem becomes more urgent with much of California’s wealth huddled along the coast, supporting an ocean-dependent $44 billion economy.
In the end, state and local officials may come to the gut-wrenching conclusion that some coastal land should be simply abandoned.
“We’re not doing well at all,” said Assemblyman Mark Stone, a Santa Cruz County Democrat who chairs the Select Committee on Coastal Protection and Access to Natural Resources. “We have yet to really start to answer the hard questions and make policy — saying, ‘No, we are not going to put public money here.’ Eventually we should get to the point that we are not going to do any public investment in those places any more.”
Understanding the threat of sea-level rise in California depends to some extent on where you are standing: Boots in the dust of the Central Valley and you might curse the lateness of a rail shipment held up by flooding at the port of Oakland; bare feet in the sand at Huntington Beach and you may have to consider relocating your family, your home and all your possessions.
Some simple math: Every inch of sea-level rise equates to an 8- to 10-feet loss of beach.
So, using the conservative projection of a 4-foot rise, and the lower-end 8-foot-per inch formula, that equates to 384 feet of coastal beach loss in the next 70 years.
The 10-foot rise scenario, which scientists peg as the new worst-case, would cause a land loss of 800 feet — the length of two-and-ahalf football fields.
The sobering fact of those state-of-the-art reports, recent though they are, is that they are already out of date and not nearly comprehensive enough in describing the scale of what currently faces California. Scientists say what they are observing now is a rapid and steep change that, even as it unfolds over comparatively long periods of time, is nonetheless occurring at a breathtaking pace.