HomeOutdoorsNewsHawaii’s Mauna Loa, World’s Largest Active Volcano, Erupts for First Time in 38 Years

Hawaii’s Mauna Loa, World’s Largest Active Volcano, Erupts for First Time in 38 Years

by Samantha Whidden
(Photo by © CORBIS/Corbis via Getty Images)

Hawaii’s Mauna Loa, which is dubbed the largest active volcano, has officially erupted for the first time in nearly 40 years.

According to CNN, Mauna Loa’s eruption has sparked an ashfall advisory on Monday (November 28th) for Hawaii’s Big Island and surrounding waters until 6 a.m. HST (11 a.m. ET). It was reported that up to an inch of ash fall is predicted to accumulate on portions of the island. 

The National Weather Service in Honolulu further issued a statement about Mauna Loa and the ashfall. “People with respiratory illnesses should remain indoors to avoid inhaling the ash particles,” the service explained. “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.”

Meanwhile, Hawai’i Tourism Authority issued a statement about Mauna Loa’s eruption stating that the phenomenon is not threatening downhill areas or even flights to the island of Hawaii. “We are closely monitoring the eruption of Mokuʻāweoweo, which is not currently threatening communities downhill or affecting flights to the Island of Hawaiʻi.”

The Hawaii Volcano Observatory also reported that Mauna Loa’s Lava flows are in the summit area and do not threaten downslope communities. “Based on past events, the early stages of a Mauna Loa eruption can be very dynamic,” the observatory also explained. “And the location and advance of lava flows can change rapidly. If the eruption remains in Moku’āweoweo, lava flows will most likely be confined within the caldera walls. However, if the eruptive vents migrate outside its walls, lava flows may move rapidly downslope.”

Hawaii’s Mauna Loa Has Erupted 33 Times Since 1843 

CNN further reports that Mauna Loan covers half of the island of Hawaii. It has erupted 33 times since 1843. It last erupted in 1984. Which makes the past 38 years a “prolonged quiet period” for the volcano’s recorded history. 

The U.S. Geological Survey also said that Mauna Loa has been in a “heightened state of unrest.” This is due to the elevated seismic activity and increased earthquake rates. 

Meanwhile, earthquake activity notably increased from five to 10 earthquakes a day in June 2022 to 10 to 20 earthquakes a day in July and August 2022. Peak numbers also revealed more than 100 earthquakes a day were recorded on September 23rd and 29th. The eruption comes just a couple of weeks after more than 50 earthquakes rattled Mauna Loa over a 24-hour period. 

The increase in earthquake activity did cause the Mauna Loa summit to be closed. “Mauna Loa summit, cabins, and high-elevation areas are closed due to increased seismicity,” the Hawaii National Parks website currently reads. However, the website has not been updated to report the eruption.