US authorities said that Hawaii’s Mauna Loa, the largest active volcano in the world, erupted on Monday for the first time in nearly 40 years, spewing lava and ash as rescue services were alerted.
The United States Geological Survey issued a report at 11:45 pm local time on Sunday (9:45 pm GMT Monday), about 15 minutes after the eruption inside Hawaii Volcanoes National Park, stating that the lava flows were largely contained within the summit’s enormous caldera but the eruption could threaten nearby residents should circumstances change.
The USGS reported that Mauna Loa has been erupting for years and that Kona, a town on the west coast of Hawaii’s main island, can see it from a distance of 45 miles (72 kilometers) away from the volcano.
The USGS stated on its website, referring to the basin at the peak of a volcano, that “lava is still erupting from the summit & is overflowing from the caldera.” It also stated that there were “no threats to populated areas at this time,” but it urged locals to review preparedness measures.
The USGS warns that lava flows “may move swiftly downslope if the eruptive vents migrate outside its walls.”
The organization stated that the Hawaiian Volcano Observatory was speaking with emergency responders and that its staff would conduct an aerial reconnaissance over the 13,674-foot (4,168-meter) volcano as soon as practical.
Authorities in Hawaii reported that no evacuation orders had been issued, despite the summit area, a number of nearby roads, and the opening of two shelters as a precaution.
A light accumulation of ash is anticipated to accumulate on ships in ocean waters along the southeast of the Big Island, according to an ashfall advisory for areas downwind of the volcano.
Long, bright eruptive fissures within the volcanic crater were visible on a USGS webcam on the summit’s northern rim, standing out against the nighttime darkness.
A greater threat arises, according to scientist and volcanologist Robin George Andrews, if magma starts to erupt from so-called rift zones on the volcano’s flanks.
The fact that Mauna Loa hasn’t erupted since 1984 — the longest eruptive pause in its documented history — is why we should all keep an eye on it, according to Andrews, even though there isn’t any evidence of it happening right now.
Mauna Loa, whose name means “Long Mountain,” is the largest volcano on Earth by volume. It occupies half of the Big Island and is bigger than all the other Hawaiian islands put together.
The USGS estimates that the summit of Mauna Loa is about 17 kilometers (55,700 feet) above its base. This is due to the volcano’s submarine flanks, which extend miles below sea level to the ocean floor. Mauna Loa’s great mass also causes the ocean floor to be depressed.
One of six active volcanoes on the Hawaiian islands, Mauna Loa has erupted 33 times since 1843, according to USGS.
The most recent eruption, in 1984, lasted 22 days and produced lava flows which reached to within about seven kilometers (four miles) of Hilo, a city to the northeast which is home to about 44,000 people today.
Kilauea, a volcano on the southeastern flank of Mauna Loa, erupted almost continuously between 1983 and 2019, and a current minor eruption there has been ongoing for months.