On Monday around 2:30 a.m., Kilauea volcano started erupting within Halemaumau crater in the summit caldera. 

About two hours later, lava fountains on the floor of the southwest part of the summit caldera were seen with heights up to 262 feet. The vents ejected “lava bombs,” which landed up onto the west caldera rim. The surrounding area, which is within Hawaii Volcanoes National Park, is closed, so it’s not considered a safety concern.

By 5:30 a.m., lava covered an estimated area of 400 acres of the caldera floor. 

The Hawaiian Volcano Observatory said the eruption stabilized around 6:30 a.m. and there are no immediate threats to infrastructure, according to a news release.  

HVO lowered Kilauea’s volcano alert level from “warning” to “watch” and its aviation color code from “red” to “orange.” 

However, vents continue to erupt on the floor of the summit caldera. 

The high levels of volcanic gas, which can have far-reaching effects downwind of the summit, are the main hazard of concern, according to HVO. The plume of volcanic gas and fine volcanic particles is reaching elevations of 8,000 feet above sea level and winds are transporting it to the southwest. The Department of Health warned that air quality levels are elevated at the Ocean View and Pahala monitoring stations.

DOH advises people to be mindful of vog conditions and provide a few tips: reduce outdoor activities that cause heavy breathing, individuals with asthma or chronic respiratory disease should always have medications available and people experiencing health effects should contact their medical provider as soon as possible if they develop symptoms, as respiratory conditions might worsen rapidly in heavy SO2 or vog conditions.

The Hawaii Volcanoes National Park said in a news release that visitors hoping to see the eruption should be prepared for crowded overlooks, full parking lots and busy roads. Strong winds are blowing the plume of volcanic gas away from viewing areas toward an area of the park that has been closed since 2008, according to HVNP. 

From the northwest rim of the caldera, looking south (Photo courtesy of USGS)
From the northwest rim of the caldera, looking south (Photo courtesy of USGS)

 

The science of volcanic eruptions

“The nature of eruptions at Kilauea has really changed, starting with the 2018 eruption,” said Steven Lundblad, a University of Hawaii Professor of Geology, referring to the lower Puna eruption that covered parts of Leilani Estates and Lanipuna Gardens subdivision with lava. 

Before this, Kilauea was “reasonably stable” for about 35 years, erupting at the caldera from 1983 until April 30, 2018, when the summit of Puʻuʻōʻō collapsed and magma started to move underground to the middle and lower East Rift Zone. “(It was a) reorganization of the plumbing system,” Lundblad said.  

Since this turning point, Kilauea has had five shorter eruptions in the summit and two shorter eruptions near the summit (one at the Southwest Rift Zone and another at Nāpau Crater). 

The Hawaiian Volcano Observatory tracks earthquakes, ground inflation, and ground tilting to predict when these eruptions are imminent. These are all signs that magma is moving beneath the surface of the earth and it will eventually need to find a place to come out. Because of this tracking system, the eruption wasn’t unexpected, but Lundblad said scientists still didn’t know exactly when it would start. 

After the eruption started, HVO staff collected tephra — the material being ejected from the lava vents — and Lundblad will now test those samples to determine their composition. “That tells us something about what was going on below the surface,” said Lundblad. The composition of the tephra provides insights into whether the magma is similar or different to magma from previous eruptions, revealing trends or patterns in the volcano’s eruptions. 

When asked whether Monday’s eruption at Kilauea has any bearing on a possible eruption at Mauna Loa, Lundblad said scientists still don’t know enough about the connection between the two volcanoes. Since 1950, Mauna Loa has only erupted three times (1975, 1984 and 2022), while Kilauea has been very active. Because of this, scientists don’t have enough data on Mauna Loa. He said there is likely a “plumbing system” deep down that connects the two volcanoes. However, Lundblad added, “this eruption isn't necessarily going to do anything to influence directly what's happening up at Mauna Loa.”

Michelle Broder Van Dyke covers the Hawaiian Islands for Spectrum News Hawaii. Email her at michelle.brodervandyke@charter.com.

Editor's note: This article was updated with information from the Department of Health, the Hawaii Volcanes National Park, and Steven Lundblad, a University of Hawaii Professor of Geology. (Dec. 23, 2024)