ADVERTISEMENT

King Tides May Help Prepare Californians to Cope with Rising Sea Levels

Powerful tides provide a present-day glimpse of what future tides may look like



Wikimedia Commons/Kglavin

STINSON BEACH, Calif. -- The Pacific Ocean laps against a seaside property in the small Northern California town. If it comes a foot closer, it will breach the black-painted concrete wall that surrounds the wooden house on three sides.

The threatening water isn't the work of rising sea levels, but rather of "king tides," which occur when the sun and moon's combined influence is highest. They're not caused by climate change, but according to activists and experts, they provide a convenient way to see what everyday tides might look like decades from now.

It's an image experts want people to contemplate. State agencies and environmental groups are taking reporters out on boats, holding nighttime events and combing the coast in an effort to get people to think about what it will mean for sea levels to rise as much as 3 feet by the end of the century, as U.N. scientists have projected.

"It's an issue that most legislators and policymakers are tracking, but are largely unwilling to take bold action to address," said Sara Aminzadeh, program manager with California Coastkeeper Alliance.

The state's Ocean Protection Council issued a document in 2010 finding that the state could see 40 to 55 inches of sea-level rise by 2100, but it doesn't require agencies to take steps to address it.

The OPC resolution "stops short of advising state agencies to restrict new development in hazard zones -- a critical step to protect public safety and our economy," Aminzadeh said.

The effort to get people thinking about sea-level rise, now in its second year, is funded by the state's Coastal Commission, the National Oceanic and Atmospheric Administration's National Estuarine Research Reserve System, and the San Francisco Bay Conservation and Development Commission, a local agency that oversees coastal development.

The agencies hope to increase people's awareness of the risk that building on the coastline may eventually entail. Several of the beachfront houses on Stinson Beach have makeshift sea walls in front of them; one has large gaps underneath it and ends in a raw edge right at the house's perimeter.

That's not the best adaptation strategy, according to environmental groups like California Coastkeeper Alliance.

"Given everything we know about how sea walls impact public access to the coast, coastal habitats and shoreline property values, it is ecologically and economically irresponsible to further armor our coast," Aminzadeh said.

An issue that always seems distant
The group evaluated its messaging last year and found that policymakers viewed sea-level rise as a more distant environmental issue. It's now focusing more on sea-level rise's effect on people, rather than wildlife, and trying to illustrate the phenomenon visually through local examples of beaches, homes and roads vulnerable to flooding.

Lesley Ewing, a senior coastal engineer with the Coastal Commission, said the state's 1976 Coastal Act provides enough authority to regulate coastal development as climate change progresses. "Staff has always been of the opinion that the Coastal Act has already incorporated sea-level rise," she said. "There may in the future be opportunities to strengthen our policies for sea-level rise, but we do have the opportunity to look at risks to property based not just on current conditions, but also conditions that may happen in the future."

Outdated plans don't help
It's hard to know exactly how many cities are addressing sea-level rise or even climate change in their coastal plans. The Coastal Commission doesn't keep statistics. "We don't have that piece of information," said coastal program manager Liz Fuchs. The agency did issue guidance in 2007 suggesting that jurisdictions take "sea level rise, from both a short- and long-term perspective," into account, but there is no requirement that they do so.

Meg Caldwell, a former chairwoman of the Coastal Commission, said that, based on her observations, very few have -- "on the order of fewer than five fingers."

Caldwell pointed to Humboldt County and Malibu as good examples; the latter revised its plan to account for rising sea levels after years of legal wrangling with the state.

"It's completely understandable that so many of them are out of date," she said in an interview. "However, it just means that when circumstances have changed and our level of knowledge about the environment and about changing conditions like climate change get to a point where we all recognize that our long-term planning really needs to be revisited, it's going to take a long time for that to reverberate through the system and for people to undertake that kind of effort."

The state may be able to exert more control over local coastal planning than it now does. The Coastal Act allows cities and counties to form their own local coastal plans, which the commission then has to approve in order for them to gain local control of permitting decisions.

But according to agency figures, of the roughly 128 plans, only slightly more than half have been certified by the commission. The agency also has no authority to require them to be updated every five years, as the law specifies.

Caldwell thinks the agency could do much more. In a 2007 paper in Ecology Law Quarterly, she laid out ways the state could exercise its authority, including creating "rolling easements" that would require landowners to retreat as levels rise.

Researchers Susanne Moser and Juliette Hart are in the midst of updating a survey of coastal managers' attitudes toward sea-level rise, funded by NOAA and several state agencies. A 2005 questionnaire found that local officials were largely aware of the risks but that budget constraints and more pressing issues were keeping them from taking action.

Local measures might be more effective than revising coastal plans with the Coastal Commission, said Phyllis Grifman, associate director of the University of Southern California's Sea Grant Program, which is supporting the survey. "I think it's more in the consciousness of managers than it was five years ago," she said.

She said raising awareness of king tides and climate change would help advance local policies, as in the case of Los Angeles, which is working on a municipal plan to reduce emissions. "The election cycle is so different from the normal cycle that people work under, it is beneficial to have the public knowledgeable or at least aware of this, because that's who pushes the agenda for politicians," she said.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

Share this Article:

Comments

You must sign in or register as a ScientificAmerican.com member to submit a comment.
Scientific American MIND iPad

Give a Gift & Get a Gift - Free!

Give a 1 year subscription as low as $14.99

Subscribe Now >>

X

Email this Article

X