Seismologists monitoring Mauna Loa have detected a recent increase in earthquakes near the summit. While an eruption is not imminent, they have issued an alert, and Hawaii’s civil defense agency has begun preparing for a possible emergency.
The Hawaiian Volcano Observatory warned the peak has been in a state of “heightened unrest” since mid-September, when earthquakes jumped from roughly 15 per day to roughly 45 per day. This is likely because magma has begun flowing into the summit’s reservoir system underground.
Residents have been advised to prepare a “go” bag with food and to have a pre-set place of refuge to go in case they have to flee their homes in a hurry.
The 13,600-foot-high volcano, a broad shield-style mountain, hasn’t erupted since 1984, but its runny lava flows are still capable of posing a risk to humans living nearby, especially in Hilo, a city of 45,000 on its northeastern slope. More than 200,000 live on the “Big Island,” Hawaii, formed by Mauna Loa and four other volcanoes, two of which are dormant and one of which is extinct.
Hawaii residents are typically exposed to greater danger by Mauna Loa’s much smaller sister volcano to the east, Kīlauea, which has been in continuous eruption since September 2021. It is one of the world’s most active volcanoes, having previously vented lava from hotspots on its eastern side from 1983 to 2018.
However, last year scientists warned that Mauna Loa was slowly “waking up” from its slumber after detecting another prolonged cluster of earthquakes at the summit.