A few weeks ago, Mauna Loa, the world’s largest active volcano, situated on the island of Hawaii showed signs of activity such as low-magnitude earthquakes and inflation of the ground, testament to underground magma on the move. Just this weekend, the 74-mile behemoth (and this measurement is from the edge of the volcano to the rim of its summit crater!), started erupting for the first time in nearly 40 years. Mauna Loa takes up more than half of the Big Island and stands at 13,681 feet (4170 meters) above sea level. Back in 1984, when it erupted last, lava came within 5 miles of the city of Hilo. Kilauea, a nearby active volcano, last erupted in 2018, destroying over 700 homes, devastating residential areas. The summit area was changed by tens of thousands of earthquakes and a massive collapse of the Kilauea caldera. It was a volcano that I studied for a field camp back in 2006 with the Center for the Study of Active Volcanos at the University of Hawaii – Hilo.


Ricardo and I traveled to Hawaii in 2019, for our Summits, Songs and Science Project, where he cycled from the sea, near Hilo, to the base of Mauna Kea at 9,200 feet. From there, we hiked together to the summit of this volcano, at 13,803 feet. Before our flight home, we had a few hours and, while not having enough time to summit Mauna Loa, we did hike there, as well as saw the climate observatory (11,135 ft./3397 meters) where data collection has generated the famous “Keeling Curve”. This curve shows monthly carbon dioxide patterns dating back to the 1950s. The overall trend is rising carbon dioxide while the see-saw nature is due to changing seasons (when plants die in the fall and bloom in the spring).


The lava on Mauna Loa has migrated from the summit to its northeast rift zones, where fissures are feeding several lava flows. Currently, there are no threats to populated areas. However, as of yesterday morning, lava crossed the access road to the Mauna Loa observatory and taken out powerlines to the site, resulting in a pause to data collection and no access to the facility. The US Geological Survey is keeping a close eye in case the lava flows change course and threaten populations.

photo: by Ricardo Peña of Ulyana Peña on Mauna Loa, 2019.