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Kilauea Volcano Explodes

Hawaii’s volcano has been erupting for more than two weeks and has entered a new explosive phase

May 22, 2018
By Karina Hamalainen
U.S. GEOLOGICAL SURVEY

Webcam image of ash shooting into the sky and raining down on Thursday, May 17, when Kilauea entered a new explosive phase.

For more than two weeks, Hawaii’s Kilauea volcano has been erupting. Slow-moving rivers of lava have seeped out of cracks in the volcano. The lava has covered roads and houses. But on May 17, the eruption entered a new explosive stage, shooting a plume of ash more than 9,100 meters (30,000 feet) into the air. Pebbles and larger rocks also began shooting out of the caldera. That’s the crater at the top of a volcano where lava, gases, and ash escape.

For days, scientists monitoring the volcano had been warning that an eruption like this could happen. At the top of the volcano is Halemaumau (HAH-lay-maoh-maoh) crater. Nestled inside this crater is a lake of bubbling lava. Usually, the lava in that lake stays at a certain level. But during the current eruption, the level dropped more than 215 meters (700 feet). The lava is now at its lowest level since the lake formed in 2008!

U.S. GEOLOGICAL SURVEY

A rock measuring 60 centimeters (24 inches) landed in the parking lot near the crater after being shot out of the volcano.

On May 17, the level of the lava dipped below the water table. That’s the area underground where water completely soaks the soil. When the lava drops this low, water can come in contact with the hot rocks. The water instantly boils, creating a rush of steam. The steam can shoot any rocks that fall into the crater into the air like a rocket. Some of these larger boulders could be big as refrigerators. They could land as far as 1.6 kilometers (1 mile) from the volcano. Luckily, there are no houses that close to the caldera.

These steam-driven explosions will keep on happening depending on the level of the lava. Several smaller explosions occurred through May 22, shooting smaller ash clouds into the sky. Scientists say this activity could last for weeks.

CALEB JONES/AP PHOTO

An official shows Lindsey Magnani and her son Kahele Rodrigues, 2, how to use a respirator to them to protect them from ash.

TOXIC FUMES

The biggest concern for people living near the volcano is the air pollution. All of the ash and gases, also known as vog, coming from the crater can cause breathing issues. Vog can also irritate a person’s eyes, nose, and throat. "Severe conditions may exist such as choking and inability to breathe," Hawaii County’s Civil Defense Agency wrote on its website. "This is a serious situation that affects the entire exposed population."

On May 19, the lava flow crossed a highway on the eastern side of the island and reached the ocean. When the lava hits the saltwater, it creates another type of air pollution called laze. Laze is a combination of steam, tiny glass particles, and acid gas. Direct contact with laze can cause eye, skin, and lung irritation. Longer exposure to laze can also cause lung damage. Laze travels with the wind, so authorities have warned people to stay away from these areas.

Several schools on the island closed for part of the week because of the air pollution, but have reopened since. Officials have passed out more than 2,000 masks to residents to help them avoid inhaling the ash. But the masks will not protect against the toxic gases. 

U.S. GEOLOGICAL SURVEY

Late at night on May 19, the lava flows met the sea, producing steam, tiny glass fragments, and acid gas.

AN ONGOING ERUPTION

The first stage of the eruption began with an earthquake on May 3. Since then, lava has flowed from more than 20 new fissures, or long cracks, on the side of the volcano. More than 2,000 people have evacuated the areas near the volcano.

The lava has destroyed at least 40 structures, including 26 homes in the Leilani Estates neighborhood. So far, only one person has been injured during this eruption. A man was struck in the leg by a piece of flying lava spatter, which shattered his leg. He is being treated at a local hospital. (For more on the start of the eruption, read Hawaii Volcano Erupts.)

There is no indication how much longer the eruption will last. The last time Kilauea experienced this type of explosive eruption was almost a century ago. In 1924, the explosive eruption lasted almost three weeks. It killed one person and deposited a layer of ash across the region.

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