Hawaii saw minor sea-level changes and wave height increases early Thursday morning before state officials canceled a tsunami advisory that was issued Wednesday afternoon when a magnitude 8.3 earthquake struck off Chile.
The Pacific Tsunami Warning Center canceled its tsunami advisory at 7:33 a.m.
As predicted, the first tsunami-generated wave hit the shores of the Big Island at 3:20 a.m. measuring about three feet, according to the Hawaii Emergency Management Agency.
The agency’s administrator, Vern Miyagi, said the wave action did not generate any damage.
Miyagi said a tsunami advisory is issued by the Pacific Tsunami Warning Center when the threat of a tsunami may produce strong currents or waves dangerous to those in or near the water.
Beachgoers should continue to check with lifeguards throughout the day before going in the water Thursday, officials advise.
Peter Hirai, deputy director of the City Emergency Management Agency, said the first tsunami-generated wave hit Oahu at 4:50 a.m.
Hirai said it was about a foot high and was recorded at Honolulu Harbor. No wave damage was reported on Oahu.
At 5 a.m, officials at the Pacific Tsunami Warning Center on Oahu said their gauges recorded sea-level changes of about 3 feet above normal off Hilo and they expected to see decreasing fluctuations throughout the morning. The sea-level changes decreased as the waves went further west with Kahului seeing a surge of about 2 feet above normal, and Honolulu and Nawiliwili recording waves of just a few centimeters above normal.
No evacuations were ordered and tsunami warning sirens were not activated.
State Emergency Management Agency activated its Diamond Head emergency operations center at 2 p.m. Wednesday.
The quake was measured at a preliminary magnitude of 7.9, but later upgraded to 8.3, according to the U.S. Geological Survey. It was centered near the coast of Central Chile and struck at 12:54 p.m. Hawaii time.
After the strong earthquake hit, officials immediately issued a tsunami watch followed by a statewide advisory shortly after 3 p.m. Wednesday.
“The shoreline is going to be dangerous,” Gerard Fryer, a senior geophysicist with the Pacific Tsunami Warning Center, said Wednesday during a news briefing at the center’s new headquarters on Ford Island.
Because of the tsunami advisory, Hanauma Bay and coastal areas around the state were closed Thursday morning. Many were being reopened after the advisory was lifted, but Hanauma remained closed as a precaution.
The state Department of Land and Natural Resources reopened coastal and low-lying state parks and forest areas Thursday morning, including wildlife sanctuaries, natural area reserves and game management areas, on all islands. Small boat harbors were not affected by the earlier closings, as boat owners were afforded time to take their vessels out in anticipation of turbulence.
Maui County reopened all beach parks at 8 a.m., including the Kipahulu campground at Haleakala National Park, after assessing ocean conditions.
Even as beaches and parks were reopening, officials still urged caution to ocean-users and boaters due to the possibility of strong and unusual currents generated by the tsunami.
The U.S. Geological Survey initially reported the quake at a preliminary magnitude of 7.9 but quickly revised the reading upward to 8.3. U.S. officials said the quake struck just offshore in the Pacific, 35 miles west of Illapel, Chile at a depth of 5.2 miles.
Chilean officials reported eight deaths and more than 1 million evacuated in the quake-prone South American nation.
Several Chilean coastal towns were flooded from small tsunami waves set off by late Wednesday’s quake, which shook the Earth so strongly that rumbles were felt across South America.
The quake lasted for three minutes, causing buildings to sway in the capital, Santiago, and prompting authorities to issue a tsunami warning for the Andean nation’s entire Pacific coast. People sought safety in the streets of inland cities, while others along the shore took to their cars to race to higher ground.
"I thought it was the end of the world and we were going to die," said teary-eyed Manuel Moya, 38, sleeping with his wife on the ground outside their destroyed home in Illapel, 175 miles north of Santiago and 34 miles east of the quake’s epicenter. The town and surrounding areas have about 35,000 residents.
Authorities worked into the early hours Thursday assessing damage in several coastal towns that saw flooding from small tsunami waves set off by the quake.
Numerous aftershocks, including one at magnitude 7 and four above 6, shook the region after the initial earthquake — the strongest tremor since a powerful quake and tsunami killed hundreds in 2010 and leveled part of the city of Concepcion in south-central Chile.
Although officials cautioned it was too early to know for sure, it appeared Wednesday’s quake had a much smaller impact than the 2010 tremor. If that turns out to be the case, it will be a sign that Chile’s traditionally strong risk reduction measures and emergency planning had gotten better in the last five years.
"Earthquake impact is a little like real estate: what matters is location, location, location," said Susan Hough, a geophysicist with the U.S. Geological Survey. "But it is true that preparedness and risk reduction in Chile is ahead of that in much of the world, and that makes a difference."
People in Peru and Brazil also reported feeling the shakes. No injuries were reported outside Chile.
Claudio Moreno said he was in a Santiago bar when it hit. The shaking was powerful, but more worrisome was how long it lasted, he said.
"We went out in the street when we felt it was going on too long," he said. "It was more than a minute."
Authorities said some adobe houses collapsed in Illapel.
Illapel’s mayor, Denis Cortes, told a local television station that a woman had been killed in the city but declined to give any details.
Electricity was knocked out, leaving the city in darkness. "We are very scared. Our city panicked," Cortes said.
In February 2010, a magnitude-8.8 quake and ensuing tsunami in south-central Chile killed more than 500 people, destroyed 220,000 homes, and washed away docks, riverfronts and seaside resorts. That quake released so much energy, it actually it shortened the Earth’s day by a fraction of a second by changing the planet’s rotation.
The quake had huge ramifications, both political and practical, prompting the Andean nation to improve its alert systems for both quakes and tsunamis.
A tsunami generated by the 2010 quake reached Hawaii’s shores but was smaller than expected and did not cause any substantial damage. The largest wave surge, just over 3 feet, was recorded in Kahului, while Honolulu saw tsunami waves of under a foot.
While Wednesday’s tremor was strong by any estimation, the 2010 quake was 5.6 times more powerful in terms of energy released, according to the U.S. Geological Survey.
Chile is one of the world’s most earthquake-prone countries because just off the coast, the Nazca tectonic plate plunges beneath the South American plate, pushing the towering Andes cordillera to ever-higher altitudes.
The strongest earthquake ever recorded on Earth happened in Chile — a magnitude-9.5 tremor in 1960 that killed more than 5,000 people.
Dozens of aftershocks above magnitude-4 rattled Chile as tsunami alarms sounded in the port of Valparaiso in the first major tremor since a powerful quake and tsunami killed hundreds in 2010 and leveled part of the city of Concepcion in south-central Chile.
Officials ordered people to evacuate low-lying areas along the 2,400 miles of Chile’s Pacific shore, from Puerto Aysen in the south to Arica in the north. Fishing boats headed out to sea and cars streamed inland carrying people to higher ground. Santiago’s main airport was evacuated as a precaution.