Hawaii’s Mauna Loa erupts after 38 years of dormancy

HONOLULU (CN) — The Big Island of Hawaii ended its Thanksgiving weekend with a bang of sorts — the eruption of the world’s largest active volcano, Mauna Loa.

Although national park regions near Mauna Loa have been closed and several flights have been delayed or canceled, experts with the U.S. Geological Survey’s Hawaii Volcano Observatory say Big Island residents are in no danger from lava flow.

According to the agency, the volcano began its eruption around 11:30 p.m. Sunday night, moving the island’s alert system from "watch" to an active ‘warning’ after several months of earthquakes attributed to the movement of magma under the crust observed around mid-September put the island on alert for a possible imminent eruption.   

Although lava flow has now migrated from the caldera to rift zones where fissures in the mountain can feed the flow, officials have stated that there is no threat to downslope populations. There have been no closures to public schools or public services on Big Island.

Volcano experts with Hawaii Volcano Observatory predict the lava flow will remain contained to the Mauna Loa’s Northeast Rift Zone but continue to monitor the situation with state officials.

“The early stages of a Mauna Loa rift zone eruption can be very dynamic, and the location and advance of lava flows can change rapidly,” the U.S. Geological Survey said.

Hawaii Island, also known as the Big Island, is home to four active volcanoes. Hilo, where a majority of the island’s 200,000 residents live and a major tourist center, is in the path of the Northeast Rift Zone eruption, but the feds assured residents that it would take days and even possibly weeks for threats from that scenario to reach the city.

Hawaii County mayor Mitch Roth has urged residents to be cautious, but emphasized that there are no threats or evacuations for the general community. Two shelters have been opened by Hawaii County Civil Defense Agency for Big Island residents as a precautionary measure. Officials recommend that residents prepare important documents and emergency supplies in case of evacuation.

Leading up to the eruptions, experts were mainly concerned with communities to the south of the volcano, residents of which may become trapped if lava flow blocks the road in and out of the area.

An ashfall advisory for portions of the island ended early Monday morning, but concern for volcano smog, or vog, remains a concern even for distant islands in the chain. The U.S. Geological Survey also warned that volcanic gas and ash, along with Pele’s Hair — thin strands of volcanic glass named for the Hawaiian goddess of volcanoes — may be carried downwind.

Mauna Loa last erupted in 1984. The 38 years since have marked the volcano’s longest period of dormancy since its first historical eruption in the 19th century.

The Big Island has also seen recent activity from Kilauea, the island’s most active volcano, which has been continuously erupting without threat to the community since 2021. But a 2018 Kilauea eruption collapsed the Kilauea caldera and devastated the Puna district of Hawaii Island.

Subscribe to Closing Arguments

Sign up for new weekly newsletter Closing Arguments to get the latest about ongoing trials, major litigation and hot cases and rulings in courthouses around the U.S. and the world.

Email *

Submit