A discussion Tuesday about sending the Crescent City harbor master to Japan turned into speculations about the current volcanic activity at Kilauea, Hawaii and the likelihood it could cause a tsunami that reaches Del Norte County.
Harbor Commissioner Ron Phillips said he was voting in favor of allowing the port’s CEO, Charlie Helms, to join the Rikuzentakata, Japan Sister City delegation next month because of the volcano on the Island of Hawaii.
“We’ve got a volcano just about 3,000 miles or less from us that’s threatening to blow up and cause a tsunami,” Phillips said. “I think we need to have all the experience that we can get.”
Harbor district President Pat Bailey compared Kilauea to the Indonesian volcanic island of Krakatoa, whose massive eruption in 1883 triggered tsunamis and killed more than 36,000 people, according to a 2007 Reuters article.
However, while Kilauea could experience an explosive eruption, any tsunami it may trigger would likely be localized to the Island of Hawaii, Humboldt State University geology professor Lori Dengler told the Triplicate Wednesday. And if the eruption does generate a tsunami significant enough to reach the West Coast, it probably wouldn’t be as large as the surges Crescent City experienced following the 2011 Japan earthquake, Dengler said, and its energy would likely be directed to the south.
“There’s nothing in what we see right now that suggests we’re at any more risk of something coming at us from Hawaii,” she said. “All the evidence is considerably less risky that anything is going to come to us from Hawaii than (if) we get a 9.4 earthquake in Alaska that sends us something that could be a little bit bigger than what happened in ‘64.”
Kilauea has been erupting continuously since 1983, Dengler said. She described the volcano as a complex plumbing system that extends from the summit at the Halemaumau Crater to an area to the northeast called the East Rift Zone.
In the months leading up to the most recent volcanic activity, magma had been rising, causing Kilauea’s summit to inflate, Dengler said. On May 1, the lava lake at the summit began draining and earthquake activity intensified, she said.
“Magma was clearly moving to the east, to the northeast, and then it started rupturing these fissures in the Leilani Estates area,” Dengler said, adding that the first fissures formed on May 3. “On May 4 there was a somewhat unrelated 6.9 earthquake.”
On Wednesday, an eruption at Kilauea’s summit produced an ash plume that reached 12,000 feet high, the Washington Post reported. However, it wasn’t what experts had predicted, according to the Post.
According to Dengler, scientists’ concern was if the lava level at Halemaumau Crater drops below the water table and begins to boil, the steam it generates could create a phreatic eruption, or an explosion that sends rocks and boulders into the air. But, she noted, such an eruption would be nothing like Krakatoa.
“Krakatoa blasted stuff all the way up into the stratosphere — five miles,” Dengler said. “There’s a big difference between 12,000 feet and five miles, so we’re just talking about a totally different scale of an eruption.”
At least 21 fissures have formed primarily in the Leilani Estates area, which was evacuated about two weeks ago, the Washington Post reported on Wednesday.
Reuters reported Wednesday that lava from Kilauea has destroyed 37 homes and other structures and forced roughly 2,000 residents to evacuate.
According to Dengler, two previous earthquakes in Hawaii generated tsunamis that affected the West Coast, the most recent being in 1975. In 1975 the tide gauge in the Crescent City Harbor didn’t record the tsunami, she said. The highest recorded water height, 4 feet, was at Santa Catalina Island off the coast of Los Angeles County, Dengler said. Other areas in Southern California, including Los Angeles, San Diego and Santa Barbara, registered a tsunami height of about a foot and a half from the 1975 event, she said.
“If we were to have a repeat of that event, or even one a little bigger, we could be put into an advisory status, which has happened to us a number of times,” Dengler said, referring to any potential impact to Del Norte County. “It might be necessary to keep people out of the harbor area, but we’re not talking about anything nearly as significant as what happened in 2011.”
If a significant earthquake were to cause substantial slumping into the ocean near Kilauea, Dengler said the North Coast would have roughly five hours’ warning. And with deep ocean sensors and other instruments in place, “we should have a pretty good sense of what’s headed our way,” Dengler said.
Dengler noted the North Coast’s planned response to a far-source tsunami like the one that struck Crescent City in 1964 would “have our bases covered.” She also credited Del Norte Emergency Services Manager Cindy Henderson for her emergency preparation work when it comes to tsunamis.
“We need to make sure we understand how the tsunami warning system works (and) make sure our emergency response folks are still up on their skills for evacuation,” she said. “Nobody does it better than Cindy (Henderson) and nobody does it better than Crescent City, but you gotta keep at it.”
Reach Jessica Cejnar at firstname.lastname@example.org .