The world’s largest active volcano, Mauna Loa in Hawaii, has erupted for the first time in almost 40 years. US officials have issued warnings to nearby residents to be prepared for a possible evacuation.
The eruption started at 11:30 pm local time on November 27 at Moku‘āweoweo, the summit’s caldera located inside Hawai‘i Volcanoes National Park on the island of Hawaii. Currently, the eruption is limited to the summit area, but officials caution that the situation could change rapidly.
Mauna Loa has two rift zones extending northeast and southwest from the caldera, where the volcano’s surface can crack and split. Officials have expressed concern that “very fluid and fast-moving lava” could quickly flow from these fissures, posing a threat to populated areas downstream.
US Geological Survey officials reported that lava has begun to spill out of the summit’s caldera on November 28, but there is no evidence of lava erupting from the rift zones at this time.
A warning for ashfall has been issued for Hawaii’s Big Island, with medically vulnerable residents advised to stay indoors or wear filter masks. Shelters have been opened for islanders, although there is no immediate threat to populated areas.
Mauna Loa is a giant shield volcano, standing approximately 4 kilometers tall and covering an area of about 5000 square kilometers. It has erupted 33 times since 1843, with the most significant eruption occurring in 1950 when it destroyed houses, a church, and a local highway within three hours. During its last eruption in 1984, lava flows came within 5 miles of the city of Hilo.
Volcanologists have been observing increased activity at Mauna Loa for weeks, including small, shallow earthquakes around the summit. Deeper earthquakes in the vicinity of the volcano over the past few years indicated that Mauna Loa might be preparing to erupt. Aerial reconnaissance will be conducted by the Hawaiian Volcano Observatory to assess the risks associated with the current eruption.
Scientists believe that this eruption may provide insights into the connection between Mauna Loa and another Hawaiian volcano called Kīlauea. They hope to better understand the plumbing system and how magma flows to these two volcanos. There is no indication at this point that the Mauna Loa eruption will be as forceful as the 2018 eruption of Kīlauea.
Insights:
- This is the first eruption of Mauna Loa since 1984 and it could have significant implications for the surrounding areas if the lava flow moves towards populated neighborhoods.
- Volcanologists have been closely monitoring the activity at Mauna Loa for weeks and have observed increased seismic activity prior to the eruption.
- The eruption may provide valuable information about the relationship between Mauna Loa and Kīlauea, helping scientists understand the plumbing system beneath these two volcanos.
- Although there is no immediate threat to populated areas, warnings have been issued for ashfall, and residents are advised to take precautions.
- The eruption is expected to be relatively modest compared to the 2018 eruption of Kīlauea.
