Ever since Kilauea’s eruption began to intensify on May 3, there have been questions about how long this new phase will last and how violent it might become. Kilauea has been erupting continuously since 1983, but a bit more than two weeks ago the nature and type of eruption began to change. A swarm of earthquakes struck the island, including a 6.9, and the lava lake at Halemaʻumaʻu Crater began to drop. That’s significant because, as the level of magma in the lake drops, there’s potential for interactions between the water table and the magma, creating what’s known as a phreatic, or steam explosion. That may explain what happened on Thursday morning, when Kilauea underwent an explosive eruption, sending ash some 30,000 feet into the air.
Dozens of homes have been evacuated, raising the question: Could what’s happening at Kilauea be the harbinger of a catastrophe on the scale of Krakatoa, or some other world-class disaster? The (slightly disappointing) answer, depending on your general outlook on life, is “No,” — which, we should note, is completely not the same thing as “This volcano lacks the ability to screw up your day.” If you’re on the island of Hawai’i, you are standing on land produced by volcanism. Definitionally, then, there’s some potential for disruption.
But the reason the Hawaiian eruptions aren’t considered to mount the kind of massive calamity that they might otherwise has to do with the lava flowing up from the mantle. Current Hawaiian eruptions are composed primarily of basaltic lava, which is relatively thin and fluid, hurling spectacular lava fountains into the air, but without the massive explosions of a Plinian eruption, which can travel dozens of miles into the sky as opposed to 30,000 feet. Krakatoa, which produced what’s estimated as the loudest sound heard in modern times (the Krakatoa eruption was heard 3,000 miles away), was a VEI 6 event classified as “Ultra Plinian” that resulted in the collapse of the magma chamber beneath the islands. (Some of the explosions that were heard were likely the result of interactions between magma and seawater, though the scale of any such interactions on Kilauea would be vastly smaller than the Krakatoan equivalent.)
This is NOT a fact. Krakatau and Kilauea are fundamentally different volcanoes with fundamentally different processes. Our scientists have been studying Kilauea for decades. If you want correct information, please just ask us.
— USGS Volcanoes???? (@USGSVolcanoes) May 14, 2018
What’s happening on Kilauea is serious and potentially risky to those who live there. Even when volcanos aren’t dumping an ocean of hot magma love on top of your house, the sulfur they emit can be toxic to human health. There’s good reason to be mindful of the reports and warnings around the eruption and to be careful if you actually live in Hawaii. But as far as the impact of the eruption on the wider world, this is a fabulous time to watch how a volcano builds land where land didn’t used to exist in real-time, as opposed to freaking out about how this eruption could be caused by nuclear detonations in North Korea (nope), or might trigger other eruptions elsewhere (also not happening).
Feature image by NASA