World’s largest active volcano erupts, spewing lava

Aerial image released by US Geological Survey shows lava flow from Mauna Loa volcano Monday morning in Hawaii | USGS/AFP/METSUL METEOROLOGY

The world’s largest active volcano, Mauna Loa, erupted today for the first time in nearly 40 years, prompting an ashfall warning on Monday for the Big Island of Hawaii and surrounding waters. The eruption at Hawaii Volcanoes National Park does not threaten settlements or flights.

Mauna Loa is erupting at the summit.

Mauna Loa Road in Hawaii Volcanoes National Park is closed from the Kīpukapuaulu (aka “Bird Park”) roundabout. https://t.co/n72jkxarOr pic.twitter.com/RANxBJQI16

— Hawaii Volcanoes NPS (@Volcanoes_NPS) November 28, 2022

Even so, ash can accumulate on parts of the island, according to the National Weather Service in Honolulu, as winds can carry fine ash and volcanic gas with the wind. “Persons with respiratory illnesses should remain indoors to avoid inhaling ash particles and anyone outside should cover their mouth and nose with a mask or cloth,” the Honolulu office warned.

The National Weather Service in Honolulu also warned in its advisory of “possible damage to crops and animals, minor damage to equipment and infrastructure, with reduced visibility”. The ash fall can damage vehicles and buildings, contaminate water supplies, damage or kill vegetation and affect the power grid, according to the meteorological service.

Around 11:30 pm HST last night, @NOAA‘s #GOESWest 🛰️ captured the eruption of Hawaii’s #MaunaLoa volcano, inside @Volcanoes_NPS🇧🇷

This imagery shows the heat signature and the sulfur dioxide released from the #volcano‘s summit caldera, Moku’āweoweo. pic.twitter.com/gHEG63rbLb

— NOAA Satellites (@NOAASatellites) November 28, 2022

Here’s the thermal signature of the Mauna Loa eruption via #GOESWest🇧🇷 https://t.co/MlAf1ZUR2E pic.twitter.com/hGwrVl16wx

— UW-Madison CIMSS (@UWCIMSS) November 28, 2022

The lava flows are contained within the summit area and do not threaten downhill communities, the Hawaii Volcano Observatory said. The volcano’s glow was unlike anything seen before, said Kailua-Kona resident Matthew Liano.

“Based on past events, the early stages of a Mauna Loa eruption can be very dynamic and the location and advancement of lava flows can change rapidly,” the Hawaii observatory said, adding that “if the eruption follows the flows of lava will likely be confined within the caldera walls.” “If eruptive vents migrate outside their walls, lava flows can move quickly downhill,” he said.

At approximately 11:30 pm HST this evening, November 27, an eruption began in Moku’āweoweo, the summit caldera of Mauna Loa, inside Hawai’i Volcanoes National Park. Winds may carry volcanic gas and possibly fine ash and Pele’s hair downwind.
Photo Credit: USGS pic.twitter.com/ai1vEFAwnX

— NWSHonolulu (@NWSHonolulu) November 28, 2022

Mauna Loa, which covers half the island of Hawaii, has erupted 33 times since 1843, the volcano’s first “well-documented historical eruption,” according to the United States Geological Survey. The volcano last erupted in 1984, making it the longest period of calm in the volcano’s recorded history.

These photographs were taken by Ken Hon, Scientist in Charge of HVO from Waikoloa at about 1:27am. #MaunaLoa #MaunaLoaErupts

Lava is still erupting from the summit & is overflowing from the caldera. No threats to populated areas currently. https://t.co/yLBkg85jMa pic.twitter.com/vhScY3WGjR

— USGS Volcanoes🌋 (@USGSVolcanoes) November 28, 2022

Mauna Loa’s summit crater is about 34 kilometers west of Kilauea, a smaller volcano whose months-long eruption in 2018 spewed lava into the Leilani Estates neighborhood, destroying more than 700 homes and displacing residents. Its seismic activity has increased from five to 10 earthquakes a day since June 2022 to about 10 to 20 earthquakes a day in July and August, according to the USGS.

Increased activity prompted Hawaii Volcanoes National Park in October to close the summit of Mauna Loa to all inland hikers until further notice, although the US National Park Service said the main section of the park remained open.

Mauna Loa is one of five volcanoes that together make up the Big Island of Hawaii, which is the southernmost island in the Hawaiian archipelago. Mauna Loa, peaking at 4,169 meters above sea level, is the much larger neighbor of Kilauea Volcano. Your lava can flow much faster. During a 1950 eruption, lava from the mountain traveled 15 miles to the ocean in less than three hours.