Hawaii island eruptions come to an end

It was only a couple of days ago that Hawaii island was sporting two erupting volcanoes mesmerizing the masses with the awe-­inspiring power of nature.

Today there are none.

Scientists at the Hawaiian Volcano Observatory on Tuesday declared both the Mauna Loa and Kilauea eruptions over, saying the production of lava, volcanic gases and seismicity on both mountains either ended or diminished to negligible amounts.

With alert levels for both volcanoes reduced from watch to advisory on the same day, it begs the question: Is there a connection?

Maybe, maybe not, Ken Hon, HVO scientist-in-charge, told reporters Tuesday.

He said while there’s a theory that Mauna Loa relieved some pressure from Kilauea or caused physical changes that helped it to stop erupting, scientists had been noticing Kilauea’s eruptive output and signals slowly diminishing even before Mauna Loa started going off.

“There’s a lot of data, and over the next year or so, we will be combing through this data to see if we can learn more about the relationship between the two volcanoes,” Hon said.

Both volcanoes began showing outward signs of slowing down last week.

For Mauna Loa, which came to life late Nov. 27 for the first time in 38 years, the beginning of the end appeared to start Thursday, when the main flow threatening Daniel K. Inouye Highway was cut off from the lava supplied by Fissure 3, the eruption’s only active vent.

By Saturday all of the Mauna Loa flow channels had drained, and lava production was limited to the cone at the vent.

Hon said that if you peer into the vent through a hole in the cone, you can still see glowing lava.

“Every once in a while, gas coalesces inside of the dyke and rises as a large bubble and causes a small blast, throwing a little bit of spatter out,” he said.

But it’s nothing like the 100-foot-plus fountaining seen just a few days earlier, he said.

Hon said almost no sulfur dioxide gas is coming out of the vent at this point, and scientists are recording few earthquakes around the summit, indicating that the mountain is depressurized.

Another sign pointing to the end is that volcanic tremor at the vent has diminished to “almost nothing.”

“So all of those aspects show that the volcano is no longer erupting, which goes along with what we’re seeing in the field,” Hon said.

Hon said scientists are still recording steady inflation at the summit, indicating that magma is coming into the volcano’s magma chamber.

But that chamber is now depressurized, unlike its state prior to the eruption, when the newly arriving magma was pushing on a full chamber, causing a lot of earthquakes.

“Now that whole thing is relaxed and sort of filling back up, but it’s not pressurized at this point,” he said.

Hon said HVO is estimating that 200 million to 250 million cubic meters of lava erupted from Mauna Loa over the 12 days it was active.

By comparison, the eruption produced about one-fifth of the lava generated by the 2018 Kilauea eruption, he said.

Still, the 2022 eruption was a bit larger than the average Mauna Loa eruption, which is 150 million to 200 million cubic meters of lava.

In the end, the duration of the event that ended the longest period of repose in Mauna Loa’s recorded history lasted about the average length of a historic high-effusion Mauna Loa eruption, he said.

Kilauea, which began its current eruption, which was confined to the summit, on Sept. 29, 2021, was described as being on pause since Sunday, according to HVO daily updates.

But now, “We think Kilauea quit erupting between the 6th and 9th of December,” Hon said Tuesday.

The surface of the Halemaumau Crater lava lake has been cooling steadily, he said, and the crater floor, which sits on a bigger pool of lava, has only contracted and lowered in level within the crater.

“It’s true,” said Jessica Ferracane, spokesperson for Hawai‘i Volcanoes National Park. “What’s the old Hall and Oates song? ‘She’s Gone.’ There is no discernible glow from Kilauea.”

During Mauna Loa’s 12-day revival, volcano watchers were treated to a rare double eruption lighting up the Big Island sky.

More than 30,000 vehicles visited a newly created volcano-viewing area that was established to increase safety on Daniel K. Inouye Highway, allowing folks to see the spectacular fountains and glowing rivers at a safe distance.

Hawaii island Mayor Mitch Roth said Tuesday that the viewing area would begin winding down toward a permanent closure by Friday. The viewing area will be open today and Thursday from 4 p.m. to midnight, after which it will shut down permanently.

“We’re proud to have stood up a safe access point to the Mauna Loa eruption for our residents and visitors to enjoy the beauty of Pele,” Roth said in a news release.

The Gil Kahele Recreational Area will remain open 24 hours daily past Friday for anyone looking to view the remnants of the eruption. Both the upper and lower restroom areas will be available, and officials are asking visitors to keep their visits under 90 minutes.