The tsunami generated by an 8.9 earthquake off Japan doesn't appear to have produced noticeable waves in San Diego County. There was no apparent surge or increase in wave height in La Jolla, where scientists said that tsunami waves up to 2.3' high were possible. The first waves were expected by 8:41 a.m.
- WEST COAST AND ALASKA TSUNAMI WARNING CENTER
- SCRIPPS INSTITUTION OF OCEANOGRAPHY
"But the response to tsunamis could last for hours, so we might see something," said Frank Vernon, a Here's how the 8.9 earthquake was registered on a seismometer on Mt. Soledad in La Jolla. This image if from the Scripps Institution of Oceanography's Anza Seismic Network.
research seismologist at the Scripps Institution of Oceanography."It's more likely we'll measure something on the tide gauges."
However, there was a noticeable drop of water level, by 1 to 2 feet, in the Mission Bay channel leading to the ocean, about 9:15 a.m., said Maurice Luque, spokesman for the San Diego Fire-Rescue Department.
He said the water was returning, slowly, through the channel and back to the bay and Quivera Basin, by about 9:40 a.m.
"It's subtle," Luque said. "It's not disruptive in any way. It's not a strong surge."
Scientists said the energy from the tsunami -- which started about 5,800 miles northwest from San Diego -- was expected to appear shortly after a low tide, if it showed at all. Researchers have limited ability to forecast when and where tsunami waves will reach distant shores.
A magnitude 8.9 earthquake that erupted off Japan on Friday produced a tsunami that could briefly generate waves up to 2.3 feet along the San Diego County coastline starting at approximately 8:41 a.m. Friday. And the tsunami will generate potentially hazardous currents, says the National Weather Service. (San Diego surf webcams.)
And there was little chance that big waves would hit San Diego.
"We are in a different tectonic region than Japan or Cascadia or Indonesia," said Vernon, whose office overlooks Scripps Pier. "We have strike-slip faults earthquakes. The main fault (San Andreas) is inland from us. The major faults in japan and Cascadia and Indonesia are offshore where, where the tsunamis can be generated."
With the coast fogged in, people hoping to see any major waves were being advised to stay home. Luque said there were no beach closures.
Luque told people in San Diego concerned about the waves to not call 911, but instead dial 619-570-1070 for information.
"People have jammed emergency lines," Luque said.
Residents in the rest of the county may dial 211 for information about the tsunami.
Luque said San Diego lifeguards and police have been patrolling beaches from La Jolla south to Ocean Beach, advising people to stay out of the water until the expected strong surge passes. He said waders could be knocked off their feet and swept out away from shore.
The U.S. Coast Guard urged boaters to not get underway, and to use double mooring lines to secure their vessels to prevent damage.
In Chula Vista, police Lt. Scott Arsenault said he had sent officers to check transient camps at the mouths of the Sweetwater and Otay rivers in case the bay water surged somewhat upriver. He said officers were advising transients who may not have heard of the tsunami or warnings to stay away from the shoreline and to move to higher ground for a time.
The ocean surge would pose no danger to the San Onofre Nuclear Generating Station, according to a statement issued by Southern California Edison, which operates the power plant in northern San Diego County, near the Orange County line.
"The plant's protective measures include a reinforced tsunami wall 30 feet above sea level," said company spokesman Gil Alexander in the written statement.
The news of tsunami waves heading this way did not appear to be a major worry, at least for San Diego's surfing community.
"Obviously, I'm going out surfing so this is not much of a concern," Scott Olson of Clairemont said at 6:30 a.m. Friday. "If there had been big waves in Hawaii, I might have thought differently."
Rather than fear, it was curiosity that drew several hundred people to the Oceanside Pier Friday morning.
"We woke up and drove right over here," said Elena Killion, 27. "We live only eight blocks away. We heard it on the news and it was like, eww, it's gonna be 3 feet (high)."
Her boyfriend, Jason Schoen, added, "We're not worried at all. Out here on the pier is a good 18 to 20 feet off the ground."
Schoen said if the experts were wrong about the size of the wave, he and Killion could always climb a lamp post on the pier."
Christan Hummel, 51, of Oceanside, said she heard about the tsunami from an online forum she belongs to, and hurried to the pier.
"Sometimes it's a really good thing to see things first hand," said Hummel. "Sometimes the media exaggerates."
Some emergency dispatch centers in the county received calls from distraught, confused or curious residents unsure what to make of a West Coast tsunami advisory.
Sheriff's Lt. Dave Brown, in the communications center, said one young person called 911 from Chula Vista, saying his mother wanted to know if he should stay home from school. Another caller wondered if the water would come out of the ocean.
"They should not be calling 911 to ask questions," Brown said. "If you have a problem, that's when you call us."
Brown said the number of such calls were not overwhelming for dispatchers.
At the San Diego Coast Guard Station, one caller asked whether to evacuate to the mountains to be safe. Petty Officer Henry Dunphy said they even got inquiries from Orange County residents, including one who lived near a harbor.
One helicopter, three patrol boats and a cutter were launched from the San Diego Coast Guard station between 7 a.m. and 8 a.m. to be available in case any boaters were in distress. Dunphy said they had no reports of trouble or damage to any boats at marinas or moored.
Dunphy said a pollution response team was standing by in La Jolla, a central location from which to respond in case any boats ran aground in a current surge. Another team, tasked with making sure buoys were not pulled off-station in a surge, was stationed at Oceanside harbor.
Sheriff's officials began early in the morning to prepare in case a serious tsunami wave was expected to hit San Diego County, Brown said.
He said supervisors were up at 2 or 3 a.m., making sure they had previously made maps showing potential coastal inundation zones, and plans for evacuations.
"We were ready to do anything we needed to do," Brown said. "We were up, and we had a plan."
Brown said that when it became clear that Hawaii had sustained no damage, that San Diego County would be in the clear. Deputies continued to monitor beach areas in the coastal towns where they were assigned, including Imperial Beach and cities between Del Mar and Encinitas, but Brown said by 6 a.m. "we started to lose steam."
Scientists can only estimate when and how a tsunami will affect distant beaches, partly because variations in the coastline influence the size and shape of waves. But federal scientists say the tsunami could raise wave heights 2.3' in La Jolla, 2.2' at northern Imperial Beach, and 1' at San Diego Navy Pier, which is situated inside the bay. (Complete advisory.)
San Diego County tsunami run-up zones.
"Although no widespread inundation is likely in Southern California, there is a high likelihood of strong and dangerous currents in the harbors and bays," the National Weather Service said in a statement sent out shortly after 3 a.m. today. "The strong currents will be hazardous to swimmers, and coastal structures will continue for 10 to 12 hours after the initial wave arrival.
"Coastal residents are advised to stay out of the water, off the beach and away from harbors and marinas. Wave heights and currents are amplified by irregular shoreline and are difficult to predict. The initial wave may not be the largest. Later waves may be larger. Mariners in water deeper than 600 feet should not be affected."
An 8.8 quake off Chile last year produced 1.4' tsunami wavelets in San Diego, and generated a noticeable tidal switch in La Jolla and at Oceanside Harbor. The tsunami also produced clearly visible waves in the mouth of the Santa Ana River in Newport Beach.
A tsunami advisory is in effect for coastal areas south of Point Conception, and a tsunami warning is in place north of that spot. The expected arrival time for San Diego County was based on estimates for La Jolla. (Estimated arrival times for entire West Coast.)
The biggest quake to hit Japan in more than a century was responsible for the tsunami, a phenomenon defined by NOAA as "a series of ocean waves generated by sudden displacements in the sea floor, landslides, or volcanic activity. In the deep ocean, the tsunami wave may only be a few inches high. The tsunami wave may come gently ashore or may increase in height to become a fast moving wall of turbulent water several meters high."
The Honolulu Star Advertiser reported at 12:38 a.m. HST that, "The first tsunami wave from a Japanese earthquake have reached Kauai and Oahu, according to the National Weather Service, but there are no reports of damage.
"The gauge at Nawiliwili Harbor showed a 1.5 foot increase and was rising, the National Weather Service said. The weather service says the wave is arriving on Oahu and a surge is apparent on the Diamond Head camera."
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