The world’s largest active volcano has erupted for the first time in nearly 40 years.
Hawaii’s Mauna Loa volcano on the island of Hawai’i began to erupt on the evening of November 27, according to the United States Geological Survey (USGS). The volcano alert level has since risen to “WARNING/RED.”
Rising more than 2.5 miles above sea level, the enormous volcano covers half of the Island of Hawai’i. It has erupted 33 times since its first well-documented eruption in 1843.
Mauna Loa has produced large flows of basalt that have reached the ocean eight times since 1868. It last erupted in 1984, when a lava flow came within 4.5 miles of Hilo, which was Hawaii’s largest population center at the time.
Heightened unrest in the volcano was observed in mid-September, likely caused by the inflow of magma into Mauna Loaʻs summit reservoir system.
Reservoir expansion triggered small earthquakes directly below and to the northwest of the Mokuāʻweoweo caldera. Lava flowed from the volcano’s crater and vents along the volcano’s northeast flank. Neither location is near residential areas.
Officials urged the public to stay away from these areas and told residents to keep away from areas affected by lava and be ready to evacuate if lava flows start heading toward populated areas.
“Based on past events, 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,” explained the USGS.
Lava was reportedly shooting 100 to 200 feet into the air out of three fissures roughly estimated to be one to two miles long, according to AP News.
The island chain’s last major eruption was from Kīlauea in 2018. This eruption produced large lava flows that covered land southeast of Hawai’i National Park and destroyed over 700 homes and residential areas in the Puna District.
“While the 2018 eruption was big, it went longer than we expect the Mauna Loa eruption to,” said Ken Hon, scientist-in-charge at the Hawaiian Volcano Observatory, according to Hawaii News Now.
“The average Mauna Loa eruption is really in the range of just a couple of weeks, so we don’t expect a long eruption,” he explained.
Reports from the USGS’s Hazard Notification System (HANS) on November 28 explained that lava flows are not threatening any downslope communities. The eruption will remain isolated in the Northeast Rift Zone of the volcano.
Even so, volcanic gas, ash, and Pele’s hair can possibly be carried downwind.