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What to know about the Kelvin wave raising the sea level along the West Coast · Best of: Features

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  What to know about the Kelvin Wave raising the sea level along
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  the west coast? This article is being read
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  by an automated voice generated by Everlett. Seattle, the AP, sea
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  levels along the west coast will begin to rise by up to
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  a foot this month as a series of pulses of warm water
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  called Kelvin waves hit the shoreline and move north, sparking concerns about
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  beach erosion and flooding in areas already impacted by climate change and
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  El Nino. Kelvin waves are not like tsunamis and the don't curl
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  over and crash on the beach. A better image is water sloshing
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  in the bathtub or a swimming pool during an earthquake. In the
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  ocean, the are bulges of water that lift the sea level as
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  they move along the coast. They're common during El Nino events, but
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  this year's Super El Nino could intensify the impacts, experts say. Over
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  the next week the six inch to foot tall surge will move
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  north along the California coast at about six miles per hour six
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  kilometers per hour or one hundred and fifty miles per day two
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  hundred forty one kilometers per day, bringing higher sea
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  levels to Oregon and Washington state. Experts predict the waves will continue
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  to pass through from October until February. It's not that this Kelvin
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  wave is come and flood anything on its own, said.
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  Michael Jacks, a research oceanographer with National Oceanic and Atmospheric Administration Fisheries
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  Ecosystem Science Division. Instead, it raises the baseline. If you start with
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  sea levels that are six inches higher than normal, when you have
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  really high tides, big storms or storm surges, the water levels are
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  now six inches higher, he said. The effects can be amplified, he
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  said. The waves also increase ocean temperatures and push cold, nutrient rich
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  waters deeper below the surface, which has an impact on marine life.
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  Here's what to know about Kelvin waves. How does a Kelvin wave
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  form? Kelvin waves are a fact of life during an El Nino,
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  a naturally occurring climate pattern involving the warming ocean waters, said Dylan
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  Amaya, an assistant professor in the Department of Marine, Earth and Atmospheric
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  Sciences at North Carolina State University. They form when the trade winds
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  along The
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  equator change direction. Winds blowing east to west along the equator push
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  water in the Pacific Ocean west toward Asia, Jacok said. When those
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  winds weaken or reverse direction, that bulge of water gets pushed back
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  toward the east along the equator until it hits South America. When
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  the surge of water hits the coastline at the equator, it moves
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  north and south along the North and South American coasts. The wave
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  isn't visible to the naked eye, and they won't cause boats to
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  go up and down, Amaya
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  said. It's more like a big pancake. It's wider than its deep.
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  The bulge extends twelve to twenty miles, nineteen to thirty two kilometers
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  off The
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  coast, and about two hundred meters deep, Amaya said. What are the
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  potential impacts of Kelvin waves? Many coastal communities are already grappling with
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  the impacts of rising sea levels, like the Coast, erosion eating away
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  at the beach in San Clemente, California. Waves are also getting bigger,
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  experts say. The higher sea levels could exacerbate those problems. People are
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  on edge, Amaya said.
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  The think about more flooding happening, more beach erosion, so when you
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  hear elevated sea states coastal inundation risk, I think that raises a
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  lot of anxiety. The higher sea level combined with larger than average
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  waves, from North Pacific swell, which are expected during the El Nino,
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  plus large spring tides from October to February, can cause exceptional erosion
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  on the west coast, said Sean Vitusek, a research oceanographer with the
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  US Geological Survey. Generally, the largest El Nino events of nineteen eighty
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  two to eighty three, nineteen ninety seven to ninety eight, and twenty
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  fifteen to sixteen caused west coast beaches to experience their worst erosion
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  on record, Vitusek said. The loss of protective beaches also increases waves
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  impacts and coastal flooding on property and infrastructure, he said. Things could
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  intensify over time as more waves arrive over the winter. Typically El
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  Nino are associated with five or six of these waves, Amaya said.
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  During the last major El Nino in twenty fifteen to twenty sixteen
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  there We’re five Kelvin waves. One already came through in May or
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  June, and there's evidence of a third Kelvin wave forming, he said.
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  Experts expect it to continue up the coast over The next month
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  or so. How are States responding to concerns about higher sea levels?
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  There's concern the waves could worsen challenges along the Southern California coast,
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  said Alyssa Napuri, Deputy Chief of Staff for Orange County Supervisor Katrina
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  Foley. Already waves are approaching a seaside rail line, and oceanfront homes
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  were damaged during swells last month tied to Hurricane Marie. Authorities are
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  placing emergency sand on beaches as quickly as possible, Napuri said, adding
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  that forecasts show the Kelvin waves could send water levels between six
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  to twelve inches higher. We're already struggling as it is, Napori said.
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  California Governor Gavin Newsom, a Democrat, proclaimed a state of emergency in
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  late September to prepare the state for what will likely be a
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  historic El Niño, season. The proclamation will help the state move faster
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  to protect communities, stage critical resources, and strengthen readiness before severe weather
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  intensifies, the Governor said.
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  In a statement. Experts with the Washington State Department of Natural Resources
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  are ready to respond to any disasters that might come with the
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  Kelvin waves, said spokesperson Courtney James. They regularly coordinate through the State
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  Emergency Management Division, but they have not been asked to do any
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  special preparation so far, she said. Actual damages from the Kelvin waves
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  will depend on the storms and tides magnified by El Nino, and
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  if they're stronger, the damage could be significant, Amaya said. It's too
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  too early to be sure whether this particular winter season will be
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  a record breaker in terms of this El Nino. But this El
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  Nino itself is certainly on that trajectory of being one of the
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  largest, if not the largest El Nino we've ever seen, he said.
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  Associated Press reporter Amy Taxon contributed to this story from Santa Ana,
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  California.