Hawaii's Mount Kilauea Just Erupted — but When Did It Last Erupt?

Along with an abundance of tropical foliage, gorgeous beaches, and seriously incredible coral reefs, Hawaii’s Big Island is home to one of the world’s most active volcanoes, Mount Kīlauea, which erupted on Dec. 20, 2020, placing the entire island on red alert. The eruption started with the volcano's Halemaumau crater near the summit, as per NPR, and residents were advised to stay inside for the next several days, to avoid falling ash.

The The Hawaiian Volcano Observatory (HVO) has since lowered the aviation code to orange, putting local residents at ease, though it's hard to believe this happens on a somewhat regular basis. So, how often does Mount Kīlauea erupt, and when was its last eruption? Keep reading for more regarding Big Island's Mount Kīlauea.

As previously mentioned, Kīlauea is one of the world’s most active volcanoes, with semi-regular eruptions. Prior to its most recent episode on Dec. 20, Kīlauea erupted back in spring 2018, according to Live Science, which brought far more dramatic results, including an earthquake that struck the Pu'u 'Ō'ō crater. Lava was sent flowing to the Puna district, leading to mandatory evacuations in several residential areas. Hundreds of homes were ultimately destroyed.

Kīlauea has erupted almost 40 times since 1952, with consistent activity from 1983 to 2018, according to the United States Geological Survey (USGS). A lava pond at the Halemaumau summit was also consistently active from 2008 to 2018, though it drained during the eruption that year. Visitors are advised to check the USGS website before venturing to the natural phenomenon, to ensure it's safe and open to the public, though it most likely won't be open to max capacity for a while, due to the ongoing pandemic and the latest eruption. 

Some volcanoes tend to be more explosive than others, depending on the composition of the magma. Thicker magma is more explosive (and more dangerous) because it causes massive boulders to shoot outwards, while runny magma generally just flows outwards. Lava flow is usually pretty easy to escape because it moves slowly; however, it can easily damage any habitats, homes, plants, and animals in its path.

Lava flow tends to pose more danger when it combines with mud on its way down the volcano. This can cause a mudflow, which can submerge surrounding communities with hot debris. Ash in the air can also cause serious respiratory problems, skin and eye irritation, visibility issues, and occasional travel disruptions. Flights in and out of the Big Island are most likely canceled right now, but it may be for the best, as travel in general is not advised due to the ongoing pandemic.

This was Mount Kīlauea's first eruption of the 2020s, but it's likely that it won't be its last. According to the USGS, Mount Kīlauea is still an active volcano, and the agency expects it to erupt again. Fortunately for locals, the USGS expects clear warning signs before the next eruption, though the signs may not come too far in advance. Needless to say, we're relieved that there were no fatalities or damaged property as a result of the active volcano's latest explosion.