USGS: “Kīlauea summit was erupting during October 2021, when this photo was taken. A lava lake within Halemaʻumaʻu at that time gave the plume of volcanic gas above the eruption site an orange glow, as the moon rising to the east further illuminated the scene.” (USGS photo by J. Schmith)

(BIVN) – Hawaiʻi volcanoes are not currently erupting, and during this period of inactivity, scientists reflect on the quiet. 

From this week’s Volcano Watch article written by U.S. Geological Survey Hawaiian Volcano Observatory scientists and affiliates:

Here in Hawaiʻi nei, we don’t have the dramatically changing leaf colors and brisk temperatures that mark the arrival of Fall. And as October arrived this year, our night skies were dark, with no warm orange glow indicative of lava erupting on the surface.

Kīlauea’s most recent eruption stopped on September 16. This was the briefest of the five eruptions that have occurred at the summit of Kīlauea since 2020. The eruption lasted about six days and, like the four eruptions before it, filled in a portion of the summit that collapsed in 2018.

Though Kīlauea is one of Earth’s most active volcanoes, periods of time with no eruptive activity on the surface are not uncommon. Since 2020, there have been periods lasting weeks to several months between eruptions and during which there is no active lava on the surface.

Prior to the recent summit eruptions, Kīlauea didn’t erupt for over two years following the large lower East Rift Zone eruption in 2018. Looking back at Kīlauea’s eruptive history over the past couple hundred years, periods of weeks to months or even sometimes years between eruptions are relatively common. The longest period without any Kīlauea eruptions over the past 200 years was abnormally long and lasted 18 years!

For USGS Hawaiian Volcano Observatory (HVO) staff, these non-eruptive periods offer a bit of respite from the flurry of activity that comes with responding to increased unrest or a new eruption. However, because our volcanoes erupt so frequently, these quiet periods also come with a bit of unease. HVO staff ask themselves questions such as how long will it be until a volcano erupts again? Where and when will the next eruption take place?

HVO’s monitoring network helps us to evaluate the answers to these questions. The monitoring network continuously tracks activity beneath the surface despite the surface itself appearing still. Right now, recent ground deformation south of Kīlauea summit is beginning to slow, but an increased number of earthquakes are being detected in this region due to a seismic swarm. The rift zones of Kīlauea along with other active volcanoes in Hawaii, including Mauna Loa, remain quiet. We expect to see changes to these monitoring parameters when any of Hawaii’s active volcanoes begin to show signs of unrest.

Though Hawaii’s volcanoes currently aren’t erupting, other volcanoes around the world remain active. Here in the United States, Great Sitkin and Shishaldin are erupting in Alaska, generating lava flows and ash plumes in the remote Aleutian Islands. Multiple volcanoes are active in the Democratic Republic of the Congo, Ecuador, Indonesia, Japan, The Philippines, and Russia. Individual volcanoes are also active in Chile, Ethiopia, Italy, Mexico, and Papua New Guinea.

Elsewhere in the world, volcanoes can also cause unease even when not erupting. In Italy, there is increased earthquake activity at Campi Flegrei, a caldera that includes part of the city of Naples. The dense population of people living in the vicinity of this volcanic center has garnered much attention and the situation is complicated by evacuations during previous periods of unrest there which did not escalate to eruption.

Eruptions in Hawaiʻi over the past five years have fortunately offered safe viewing, have not required evacuations, and have only minimally impacted infrastructure. However, communities living on the flanks of Hawaii’s active volcanoes should always be prepared for the range of activities that Hawaii’s volcanoes can exhibit. You and your family can be better prepared for one of the many natural hazards that can impact Island of Hawaiʻi residents by taking some time now, when it is quiet, to visit the Hawaiʻi County Civil Defense website on preparedness. Though the skies above Hawaii’s volcanoes are dark right now, they will certainly be lit up by the glow of eruptions in the future.