Two months after Kilauea began its latest eruption, the spectacle remains active within Halemaumau crater — but only barely.
The volcano has diminished substantially from its showy beginning Jan. 5 to the vigorous volcanic activity that continued in the crater until just a few weeks ago.
Hawaiian Volcano Observatory officials say the decline in lava production is tied to a sharp deflation in pressure at the summit beginning Feb. 17 and lasting a couple of days. The episode left the crater with only a bubbling of eruptive activity.
The eastern and central vents that were active earlier in the eruption are not spewing any lava at this time. And even though the lava lake remains active, it is suffering from what HVO officials are calling “weak circulation” and is mostly crusted over.
Scientists have tracked several small episodes of summit deflation and inflation over the last couple of weeks — activity that has left a slight increase in net tilt. But the summit remains deflated compared to the period leading up to Feb. 17, they said.
In addition, volcanic tremor, a seismic signal linked to subsurface fluid movement, has dropped slightly in recent weeks, and the sulfur dioxide emission rate had plunged to a paltry 250 tons per day as of Tuesday.
More vigorous eruptive activity on the Halemaumau crater floor could reappear if the summit re-inflates to earlier levels, officials said. But no one is predicting when and if that will happen.
“Even though scientists can track changes in magma supply, they can’t really say why it waxes and wanes over short time intervals,” said Ken Rubin, University of Hawaii at Manoa professor of earth sciences.
“What we can say is that if it remains on a downward trend, magma may cease to erupt at the surface for a while, returning to the interior of the volcano, until it ticks up again,” Rubin said.
This kind of behavior, he said, has occurred in the last few years, when the eruptions have been confined within Halemaumau crater.
“On the other hand, a new pulse of magma could reinvigorate the current lake,” Rubin said. “Time will tell.”
The current eruption started in the late afternoon of Jan. 5, about one month after Kilauea had gone silent following more than a year of erupting within the crater.
At least two vents were spewing 30-foot fountains of lava, and the sky above the caldera within Hawai‘i Volcanoes National Park that night — and for most nights over the next month and a half — was lit up with the brilliant glow of the volcano, a magnet for residentsand tourists alike.
Park spokesperson Jessica Ferracane acknowledged Friday that there are no guarantees with Kilauea lava viewing now. She said seeing incandescence in the crater floor is a hit-and-miss proposition, depending on conditions.
With the wet weather coming into contact with the hot lava, she said, the more interesting phenomenon of late has been the billowing clouds of steam.
“It’s blowing steam like crazy,” Ferracane said.
Meanwhile, HVO officials say there are no signs of volcanic activity on neighboring Mauna Loa, within its caldera or rift zones. Earthquake rates on the mountain remain low and there is no detectable volcanic tremor.
“Satellite imagery shows that the entire 2022 flow field is cooling and no longer active,” HVO said in its latest Mauna Loa update. “We expect additional shallow seismicity and other signs of unrest to precede any future eruption, if one were to occur.”
The world’s largest active volcano erupted Nov. 27 for the first time in 38 years, pushing between 200 million to 250 million cubic meters of lava over remote Hawaii island terrain for 12 days.
