Hawaii's Mauna Loa volcano erupts for first time in nearly 40 years

US state's Big Island placed under ashfall advisory

The ground is shaking and swelling at Mauna Loa, the largest active volcano in the world. AP

Mauna Loa, the world’s largest active volcano, began spewing ash and debris from its summit, prompting civil defense officials to warn residents on Monday to prepare in case the eruption causes lava to flow toward communities. West Hawaii Today / AP

Hawaii's Mauna Loa has erupted for the first time in nearly 40 years. US Geological Survey / AFP

Emergency crews went on alert early Monday. US Geological Survey / AFP

Hawaii's Mauna Loa is the world's largest active volcano. US Geological Survey / AP

The Mauna Loa volcano is seen erupting from vents on the Northeast Rift Zone on the Big Island of Hawaii. US Geological Survey / AP

This webcam image released by the US Geological Survey (USGS) on November 28, 2022 courtesy of the National Weather Service, shows the lava in the summit caldera of Mauna Loa in Hawaii, which is erupting for the first time in nearly 40 years. (Photo by Handout / US Geological Survey / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / US Geological Survey " - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS

This image released by the US Geological Survey (USGS) on November 28, 2022 courtesy of the National Weather Service, shows a webcam view of the Mauna Loa volcano in Hawaii, which is erupting for the first time in nearly 40 years. (Photo by Handout / US Geological Survey / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / US Geological Survey " - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS

Lava flows were contained within the summit area and were not threatening nearby communities. AP

A nearly deserted beach at the edge on an old Mauna Loa lava flow on December 16, 2016, along the Kona Kohala Coast in Hawaii. Getty Images

In 2015 six people shut themselves inside a dome at the base of Mauna Loa for a year to simulate life on Mars. AFP

The UAE built an expanded version of Nasa's isolation dome. AFP

The programme focuses social, interpersonal and cognitive factors that affect team performance during long-duration space travel, such as missions to Mars. AFP

Mauna Loa looms in the background as competitors ride the bicycle portion of the Ironman World Championship Triathlon. AP

Hawaii's Mauna Loa volcano, the largest active volcano in the world, has erupted for the first time in 38 years, prompting officials to issue an ashfall advisory.

The volcano, on Hawaii's Big Island, erupted at 11.30pm on Sunday at the Moku‘aweoweo summit caldera, the US Geological Survey said.

“If the eruption remains in Moku‘aweoweo, lava flows will most likely be confined within the caldera walls,” the agency said.

“However, if the eruptive vents migrate outside its walls, lava flows may move rapidly downslope.”

Lava flows remained restricted to the summit area and nearby communities were not immediately threatened. As of Monday, no evacuation orders were in place.

“However, lava flows in the summit region are visible from Kona,” the Hawaiian Volcano Observatory said in a Monday status report.

“There is currently no indication of any migration of the eruption into a rift zone.”

The rift zone is where the mountain splits apart and the weakening of the rock makes it easier for magma to flow out.

Hawaii's Emergency Management Agency said shelters in Pahala and in Kailua-Kona had been opened as a precaution.

Up to 0.6cm of ash could accumulate in some areas on the Big Island, the National Weather Service in Honolulu said.

Mauna Loa is one of five volcanoes that make up the Big Island, Hawaii's southernmost island.

Mauna Loa rises 4,169 metres above sea level, making it much larger than the neighbouring Kilauea volcano, which destroyed 700 homes when it erupted in 2018.

During a 1950 eruption, Mauna Loa's lava travelled 34km to the ocean in less than three hours. The volcano last erupted in 1984.

Volcano erupts near Iceland capital, mesmerising spectators

The Associated Press contributed to this report