Instead, Jaggar sent a request to the U. On December 27, four days after Jaggar had made his request, the U. Army flew 10 biplanes over two target areas and struck both with their payloads of pound MK I demolition bombs. On January 2, , the lava flow stopped, and Hilo was spared once again. Jaggar declared it to be a direct result of the bombing campaign, but some pilots and geologists expressed skepticism.
Several bombs had missed their targets, and the ones that did hit their marks did not appear to cause the sort of topographical changes Jaggar had hoped to see. April A similar bombing run was carried out on Mauna Loa during another of its paroxysms, right in the middle of World War II, when a chief concern was quenching light—from lava or bombs—that might help enemy flyers navigate. Much like its predecessor, the explosion did not appear to have a significant effect on the flow of lava, says Hannah Dietterich , a geophysicist at the USGS Alaska Volcano Observatory.
As powerful as those explosives were, they were simply no match for the might of molten rock. But 50 years later and half a world away, authorities dealing with another potential volcanic calamity decided to give explosives a fresh shot at glory—and this time it seemed to do the job. Mount Etna is a vertiginous volcano on the Italian island of Sicily that is famous for its near-constant activity. It has been erupting on and off since September and, throughout , has engaged in a jaw-dropping display of largely harmless outbursts, with dozens of skyscraper-high lava fountains shooting skyward from its summit.
Its lava threatened the town of Zafferana Etnea, population 9,, prompting authorities to look for creative solutions. That year molten rock had paved over some farmland and had neared, but failed to reach, a nearby town. Sensing an opportunity and buoyed by public pressure to divert the lava, a decision was made to deploy explosives. Wanting to be precise, engineers went on foot to plant the explosives, sliding them into small tubes dug out next to the lava channels.
The engineers sprayed water into the tubes to cool them down, but that caused dramatic temperature fluctuations that deformed the lava channel, causing molten rock to spill over the sides even before explosives could be deployed. The experiment was a failure; the blasts excavated a new non-hazardous passageway for the lava, but not much of the flow changed direction, and the opening soon sealed itself.
Still, it was a valuable pedagogical moment that prepared emergency responders for what would happen almost a decade later. When Etna erupted again in , earthen barriers were erected to try and stop the lava flow, but they were rapidly overrun. At one stage, the U. Instead of dropping bombs, they chose concrete blocks: Several helicopters hovered over a skylight in the lava tube and released blocks into it in an ultimately fruitless attempt to dam the flow of lava within.
So in May , engineers decided to try a similar tactic to the one used in A heroic dump truck driver first carved a relatively safe path up the lava-strewn mountain. Teams could then painstakingly scrape away material from the side of a lava tube, make openings, and plant explosives. The scientists who study volcanoes. BBC Earth - Volcanoes. Image source, EPA. Hawaii's Kilauea volcano has been erupting continuously for decades but a newly opened vent has threatened homes. Image source, Getty Images.
Mount Etna is the second-most active volcano in the world. Bomb it. Image source, AP. Lava tubes allows molten rock to move farther than it otherwise would.
Cool it with water. Image source, USGS. Lava stopped in the middle of a street in Vestmannaeyjar. Build a barrier. Add concrete. Image source, Thinkstock. Related Topics. Italy United States Iceland. Published 5 September Robin George Andrews is a volcanologist turned freelance science journalist. Great story, thank you. My question here is why would anyone want to return? There are lots of nice places on earth, being stuck on a tiny island with this kind of ever present threat just seems, odd.
The A. Earth Science. By Robin George Andrews. Photo: Daniel Roca AP. Shop at Amazon. Photo: M. Geological Survey AP.
Smoke rises from the lava eruption on Holuhraun, northwest of the Dyngjujoekull glacier in Iceland, Monday, Sept. Photo: Eggert Johannesson AP. Earther Earth Science. More Videos This video is no longer available. Whirlwind of lava at Hawaii's Kilauea volcano. Team uses drones to map lava in Hawaii. Watch fast-moving lava flow into Pacific Ocean. Shooting lava covers community. Lava 'river' engulfs home in minutes. Blue flames burn during Kilauea eruption. Cracks open up beneath big island home.
See damage from lava invading Hawaii. Time-lapse from the skies above Hawaii's volcano. Man hit by lava bomb describes gruesome injuries.
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