Where is Mauna Loa located? World's largest active volcano begins eruption

Mauna Loa is among the world’s largest active volcanoes. It is homed by Hawaii island’s south-central part in the U.S. and is part of the Hawaii Volcanoes National Park.

On Sunday night, November 27, Mauna Loa started erupting for the first time in close to 40 years.

An emergency crew has now been appointed and an ashfall advisory has been issued for adjacent areas.

The eruption at Mauna Loa on Sunday didn’t pose a threat to flights going to the Hawaii islands or to the downslope communities. However, according to the Hawaiian Tourism Authority’s tweet on Monday, ashfall amounting to less than one-quarter-inch can amass in certain parts of the island.

But the U.S. Geological Survey warned about the possibility that the situation might change rapidly. Hence, the alert level has been raised to a warning from an advisory.

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Mauna Loa's recent eruption began at its summit caldera and is expected to be contained within that area

On Sunday night, November 27, the eruption began at the volcano’s summit caldera, Moku'āweoweo.

In October, dozens of earthquakes and seismic activities were detected in the area. Since then, the volcano has remained in a heightened state of unrest. Following the eruption, the Hawaii Volcano Observatory also received reports of lava overflowing and spreading across the southwest portion of Mauna Loa’s crater.

Late on Monday morning, the Hawaii Emergency Management Agency tweeted:

“People with respiratory illnesses should remain indoors to avoid inhaling the ash particles and anyone outside should cover their mouth and nose with a mask or cloth. Possible harm to crops and animals. Minor equipment and infrastructure damage. Reduced visibility. Widespread clean-up may be necessary.”

Matthew Liano, a local residing in Kailua-Kona, captured the sky at the Kailua Pier before dawn. The webcam was placed along the summit’s northwest rim. It was illuminated with red hues from the volcanic eruption. Liano told CNN,

“The glow is like nothing I’ve seen here living in Kona for most of my life.”

The U.S. Geological Survey, along with the Hawaiian Volcano Observatory, issued an alert notice where it said:

"At this time, lava flows are contained within the summit area and are not threatening downslope communities. Based on past events, the early stages of a Mauna Loa eruption can be very dynamic and the location and advance of lava flows can change rapidly."

The observatory added:

“If the eruption remains in Moku’āweoweo, lava flows will most likely be confined within the caldera walls.”

If the eruption breaks outside the walls of its crater, lava flows have the chance to rapidly move downhill. The Hawaiian Volcano Observatory stated that it is currently "in close consultation with emergency management partners and will be monitoring the volcano closely to provide further updates on activity."

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Previous eruptions of the Mauna Loa

The first eruption of Mauna Loa was documented in 1843. Since then, the volcano has erupted about 36 times. Most of its eruptions have occurred within the boundaries of Moku‘āweoweo Caldera. However, the volcano has also had some lower flank eruptions either along the southeast or northeast fissure zones.

During its 1935 and 1942 eruptions, the course of the lava was threatening the city of Hilo. To divert the path, U.S. military aircraft dropped bombs into the volcano. The attempt was partially successful.

In a later eruption in June 1950, lava flow from the southwest rift’s fissure continued for 23 days, destroying a small village in its course.

Mauna Loa recorded its last substantial eruption in 1984, almost four decades before it erupted once again on Sunday, November 27.