Eruption of Hawaii’s Kilauea volcano


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Eruption of Hawaii’s Kilauea volcano

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The activity of Kilauea volcano on Hawaii’s Big Island has become destructive since early May, burning dozens of homes and forcing residents to flee. Many fissures have opened, spewing lava into neighborhoods and into the Pacific Ocean.
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The activity of Kilauea volcano on Hawaii’s Big Island has become destructive since early May, burning dozens of homes and forcing residents to flee. Many fissures have opened, spewing lava into neighborhoods and into the Pacific Ocean. (Bruce Omori/Paradise Helicopters/EPA/Shutterstock)
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A steam plume rises as lava enters the Pacific Ocean, after flowing to the water from a Kilauea volcano fissure, on Hawaii’s Big Island on May 20 near Pahoa, Hawaii. Officials are concerned that ‘laze’, a dangerous product produced when hot lava hits cool ocean water, will affect residents. Laze, a word combination of lava and haze, contains hydrochloric acid steam along with volcanic glass particles. (Mario Tama/Getty Images)
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Lava erupts and flows from a Kilauea volcano fissure on Hawaii’s Big Island on May 18 in Kapoho, Hawaii. The U.S. Geological Survey said the volcano erupted explosively on May 17 launching a plume about 30,000 feet into the sky. (Mario Tama/Getty Images)
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People play golf as an ash plume rises in the distance from the Kilauea volcano on Hawaii’s Big Island on May 15 in Hawaii Volcanoes National Park, Hawaii. The U.S. Geological Survey said a recent lowering of the lava lake at the volcano’s Halemaumau crater ‘has raised the potential for explosive eruptions’ at the volcano. (Mario Tama/Getty Images)
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Lava flows at a lava fissure in the aftermath of eruptions from the Kilauea volcano on Hawaii’s Big Island, on May 12 in Pahoa, Hawaii. (Mario Tama/Getty Images)
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Lava erupts from a Kilauea volcano fissure near a home at dawn on Hawaii’s Big Island on May 18 in Kapoho, Hawaii. (Mario Tama/Getty Images)
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Brittany Kimball watches as lava erupts from from a fissure near Pahoa, Hawaii, May 19. Two fissures that opened up in a rural Hawaii community have merged to produce faster and more fluid lava. Scientists say the characteristics of lava oozing from fissures in the ground has changed significantly as new magma mixes with decades-old stored lava. (Jae C. Hong/Associated Press)
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Lava from a Kilauea volcano fissure erupts on Hawaii’s Big Island on May 19 in Kapoho, Hawaii. (Mario Tama/Getty Images)
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People take pictures as lava enters the ocean, generating plumes of steam near Pahoa, Hawaii, May 20. (Jae C. Hong/Associated Press)
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Lava is blurred as it erupts from a Kilauea volcano fissure on Hawaii’s Big Island on May 17 in Kapoho, Hawaii. (Mario Tama/Getty Images)
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Leilani Estates residents Elizabeth Kerekgyarto, right, and Lucina Aqulina embrace before parting ways outside Kerekgyarto’s home during the evacuation of residents at Leilani Estates in Pahoa, Hawaii on May 6. (Jamm Aquino/Honolulu Star-Advertiser via AP)
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A lava flow moves across Makamae Street near Pahoa, Hawaii, May 6. Since eruptions in the Leilani Estates neighborhood began on May 3, the flows of lava have destroyed 36 structures as of May 11 — at least 26 of them homes — and covered 117 acres. (U.S. Geological Survey via The New York Times)
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Lava flows from fissures near Pahoa, Hawaii. Kilauea volcano began erupting more than two weeks ago and has burned dozens of homes. (U.S. Geological Survey via AP)
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Center lane lines are partially visible along the lava-covered road in the Leilani Estates subdivision near Pahoa, Hawaii on May 11. (Jae C. Hong/Associated Press)
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A wide angle camera view captures the entire north portion of the Overlook crater as the eruption continued May 6 at Hawaii’s Kilauea volcano. (U.S. Geological Survey)
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Lava erupts inside Leilani Estates near Pahoa, Hawaii on May 19. As lava flows have grown more vigorous in recent days, there’s concern more homes may burn and more evacuations may be ordered. (Jamm Aquino/Honolulu Star-Advertiser via AP)
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Resident Stacy Welch inspects lava next to a destroyed home in the Leilani Estates neighborhood located 250-feet from her home, which remains standing. The volcano has spewed lava and high levels of sulfur dioxide gas into communities, leading officials to order 1,700 to evacuate. (Mario Tama/Getty Images)
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Steam plumes rise as lava enters the Pacific Ocean, after flowing to the water from a Kilauea volcano fissure, on Hawaii’s Big Island on May 21 near Pahoa, Hawaii. (Mario Tama/Getty Images)
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Lava enters the ocean off Highway 137 near Pahoa, Hawaii on May 20. (Jae C. Hong/ Associated Press)
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Steam plumes rise as lava enters the Pacific Ocean, after flowing to the water from a Kilauea volcano fissure, on Hawaii’s Big Island on May 20 near Pahoa, Hawaii. (Mario Tama/Getty Images)
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Lava from a robust fissure eruption on Kilauea’s east rift zone consumes a home, then threatens another, near Pahoa, Hawaii, May 6. (BRUCE OMORI/PARADISE HELICOPTERS/EPA/Shutterstock)
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A woman takes a photo as an ash plume rises from the Kilauea volcano on Hawaii’s Big Island on May 15 in Volcano, Hawaii. (Mario Tama/Getty Images)
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U.S. Army National Guard First Lt. Aaron Hew Len takes measurements for sulfur dioxide gas at volcanic fissures in the Leilani Estates neighborhood on May 8 in Pahoa, Hawaii. (Mario Tama/Getty Images)
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Ti leaves and a bottle of alcohol are left as offerings to the Pele, the Hawaiian Goddess of Fire, on a hardened lava flow from the Kilauea volcano on Hawaii’s Big Island on May 15 in Pahoa, Hawaii. (Mario Tama/Getty Images)
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A massive flow of fast moving lava consumes everything in its path as it enters a forest, Pahoa, Hawaii, May 19. For perspective, the Cook pines trees, in the middle right of the frame, are 80-100 feet tall. (Bruce Omori/Paradise Helicopters/EPAShutterstock)
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Volunteer Jasmine Kupihea, right, hugs Keula Keliihoomalu, a local resident affected by the lava flow, at a makeshift donation center on May 8 in Pahoa, Hawaii. (Jae C. Hong/Associated Press)
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Tourists climb trees at the 18th hole of Volcano Golf and Country Club, inside Hawaii Volcanoes National Park, on May 15 to view the plumes of smoke coming from the vent inside Kilauea’s Halemaumau Crater. (Linda Davidson for The Washington Post)
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U.S. Air National Guardsman John Linzmeier looks at cracks as toxic gases rise near by in the Leilani Estates subdivision near Pahoa, Hawaii on May 18. (Jae C. Hong/Associated Press)
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An aerial view shows fissure 17 continuing to erupt, creating wide, a mile long flow of lava that now threatens homes, property, and two major thoroughfares in Pahoa, Hawaii on May 14. Eighteen fissures have been reported in and around Leilani Estate. (BRUCE OMORI/PARADISE HELICOPTERS/EPA/Shutterstock)
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Residents jam a street after being allowed to briefly return home to check on belongings and pets in an evacuation zone near volcanic activity on Hawaii’s Big Island on May 6 in Pahoa, Hawaii. (Mario Tama/Getty Images)
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An image of falling ash from Kilauea, as captured by the Hawaii Volcano Observatory’s webcam on May 17. (U.S. Geological Survey)
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Lava from a Kilauea volcano fissure erupts and burns near a home on Hawaii’s Big Island on May 19 in Kapoho, Hawaii. (Mario Tama/Getty Images)
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Residents evacuate as lava continues to overrun Hookupu Street on May 7 in Pahoa, Hawaii. (Jamm Aquino/Honolulu Star-Advertiser via AP)
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Steam and gas rise in Leilani Estates in the aftermath of the Kilauea volcano eruption on Hawaii’s Big Island on May 10. (Mario Tama/Getty Images)
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Activity continues on Kilauea’s east rift zone, as a fissure eruption fountains more than 200 feet into the air, consuming all in its path., near Pahoa, Hawaii on May 6. (BRUCE OMORI/PARADISE HELICOPTERS/EPA/Shutterstock)
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The governor of Hawaii declared a local state of emergency near the Mount Kilauea volcano after it erupted following a 5.0-magnitude earthquake, forcing the evacuation of nearly 1,700 residents. (U.S. Geological Survey via Getty Images)
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This combination of satellite images shows an area by the Kilauea volcano near Pahoa, Hawaii, on May 24, 2017, top, and on May 14 2018, bottom, after the recent volcanic activity. (Satellite Image ©2018 DigitalGlobe, a Maxar company via AP)
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Lava is seen spewing from a fissure in the Leilani Estates subdivision on Hawaii’s Big Island on May 4, where up to 10,000 people were asked to leave their homes on Hawaii’s Big Island following the eruption of the Kilauea volcano that came after a series of recent earthquakes. (FREDERIC J. BROWN/AFP/Getty Images)
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Hannique Ruder, a resident living in the Leilani Estates subdivision, walks past the mound of hardened lava while surveying the neighborhood near Pahoa, Hawaii on May 11. (Jae C. Hong)
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An ash plume rises from the Halemaumau crater within the Kilauea volcano summit caldera at the Hawaii Volcanoes National Park on May 9. (Mario Tama)
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How Did a ‘Lava Bomb’ Split a Man’s Leg Open?


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How Did a ‘Lava Bomb’ Split a Man’s Leg Open?

How Did a 'Lava Bomb' Split a Man's Leg Open?

A Hawaii man nearly lost his leg to a renegade ‘lava bomb’ launched by Kilauea volcano this week.

Credit: Mario Tama/Getty

When you think of the ways a volcanic eruption can hurt or kill, you probably imagine gooey lava streams, steaming fissures and crumbling ash columns that could turn a whole city into statues. You might not imagine the volcano belching gigantic, red-hot cannonballs at you, though — but they do that, too.

When globs of molten lava blast into the air and solidify, they become “lava bombs.” One such bomb recently struck Hawaii Island resident Darryl Clinton while he tried to put out a fire in his neighborhood. Burning ejecta from the still-erupting Kilauea volcano had lit the blaze. According to CNN, the chunk of hardened lava shot like a rocket from a fissure roughly 100 yards (91 meters) away from Clinton, set his porch on fire and sliced his leg to the bone. [Fiery Lava from Kilauea Erupts on Hawaii’s Big Island]

“It was the most forceful impact I’ve ever had on my body in my life,” Clinton told the KHON news channel. “I’ve been hit by big waves and various things. That was just incredibly powerful and hot. It burned.”

Clinton is recovering in the hospital and will be able to walk again in about six weeks, KHON reported. He is the first person seriously injured by Kilauea volcano’s recent eruptive period, which began several weeks ago. But if more folks stray too close to erupting fissures, he may not be the last.

Lava bombs, also known as volcanic bombs, are partially molten chunks of lava that explode out of volcanic vents during eruptions, harden in the air and then come crashing down again. Lava bombs can be hurled as high as 3,300 feet (1,000 m) and land still hot enough to set houses ablaze, prior studies have shown.

What’s more, depending on the size and viscosity of the lava being ejected, these bombs can change shape during flight, becoming more smooth and aerodynamic. The final shape of the bomb determines its name.

According to the American Museum of Natural History, spindle bombs spin and taper during flight and end up looking like red-hot footballs. Bread crust bombs solidify on the outside but remain fluid on the inside, resulting in gas bubbles and cracks along the bomb’s surface. Cow pie bombs land while they’re still mostly liquid; when they hit the ground, they splat like a pancake — or, you know, something you’d rather not step in on a farm.

This ancient lava bomb from a German volcano weighs more than 260,000 pounds.

This ancient lava bomb from a German volcano weighs more than 260,000 pounds.

Credit: Alamy

Luckily, the lava bomb that hit Clinton’s leg was relatively small for one of these incendiary boulders. The town of Strohn, Germany, holds one of the world’s largest known lava bombs, weighing more than 260,000 lbs. (120 metric tons) and spanning 16 feet (5 m) in diameter. This exceptional piece of house-size ordnance formed in the nearby Wartgesberg volcano, but probably never flew very far; geologists suspect the massive bomb acquired its weight and volume by rolling up and down the volcano’s crater, caking more and more lava along its edges as if nature were trying to make a lava snowman.

Lava bombs aren’t just dangerous projectiles, though; they’re also objects for research. Scientists can study these bombs to get a glimpse of the mineral compositions of volcanoes and the Earth deep beneath them.

Usually, as Clinton pointed out to KHON, you can hear the initial eruption that launches a lava bomb long before the bombs actually fall. But that doesn’t mean a stray chunk of lava won’t come flying straight out of a vent like a shell from a cannon, before you have time to run for cover. To avoid lava bomb-related injury, take heed of evacuation notices (Clinton admitted his neighborhood was under evacuation, but he felt safe in his home) — and please, no matter where you are, do not attempt to stop the lava.

Originally published on Live Science.

What on Earth Is This Fiery Blob?


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What on Earth Is This Fiery Blob?

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What on Earth Is This Fiery Blob?

This impressive blob is a 65-foot (20 meters) high lava dome fountain that was photographed in Hawaii on Oct. 11, 1969.

Credit: USGS

At first glance, it looks like a fiery monster out of “The Incredibles.” Or maybe a glowing alien orb, or a giant, irritated zit popping up above the Earth’s surface.

But it’s neither. Rather, it’s an incredibly rare, 65-foot-tall (20 meters) lava-dome fountain.

Normally, volcanoes erupt lava in powerful jets that look like fountains gone wild. But in this photo — captured Oct. 11, 1969, in Hawaii — the lava spurted out symmetrically, forming an aesthetically pleasing lava-dome fountain. [History’s Most Destructive Volcanoes]

The U.S. Geological Survey (USGS) tweeted the photo on March 29 for Throwback Thursday (#TBT), a popular hashtag used when people post nostalgic photos from their past on social media.

The red-hot lava fountain certainly is a nostalgic moment for the USGS. This particular fountain was part of the Mauna Ulu eruption, which lasted (on and off) for an astonishing five years, from May 1969 until July 1974,according to the USGS.

Mauna Ulu is a volcanic cone on the east rift zone of the Kilauea volcanoon the Big Island of Hawaii. At the time Mauna Ulu erupted, it was the longest-lasting and most voluminous eruption on Kilauea’s eastern side in at least 2,200 years, the USGS said. The 1,774-day eruption spewed out about 460 million cubic yards (350 million cubic meters) of lava — enough to fill 140,000 Olympic-size swimming pools.

Mauna Ulu no longer holds the record for the longest-erupting volcano. Pu’u ‘Ō’ō, a volcanic vent on Kilauea’s east rift zone, has erupted nearly continuously since January 1983, according to a 2003 report from the USGS. But despite Pu’u ‘Ō’ō’s feat, “the Mauna Ulu eruption was more accessible to the public, with a viewing platform established at one point to observe a lava lake in the crater,” the USGS said.

The fountain pictured here spewed out lava from Oct. 10 to Oct. 13, 1969, relatively early in Mauna Ulu’s epic eruption. (As a side note, the perspective of the photo makes it look as if the lava were coming out of the water. But it’s actually on land, and those “waves” are ripples of lava.)

Typically, lava fountains occur when gas bubbles rapidly form and expand in molten rock, which prompts jets of lava to spray outward, the USGS said. Though impressive, Mauna Ulu’s fountain wasn’t on the big side; lava fountains range from about 30 to 330 feet (10 to 100 m) in height, and some have reached the incredible height of 1,640 feet (500 m), the USGS reported.

Geologists have found that lava fountains can gush out of isolated vents and fissures, from active lava lakes and from lava tubes that are exposed to water.

Original article on Live Science.

8 Trillion ‘Gallons’! Huge Blob of Magma Found Atop Undersea Volcano


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8 Trillion ‘Gallons’! Huge Blob of Magma Found Atop Undersea Volcano

 8 Trillion 'Gallons'! Huge Blob of Magma Found Atop Undersea Volcano

Credit: Shutterstock

A giant undersea caldera near Japan hosts a lava dome made from 8 trillion gallons of molten rock.

The dome, which is 6.2 miles (10 kilometers) wide and 1,968 feet (600 meters) tall, is solid rock now, and it doesn’t presage an impending eruption. However, it does add a new wrinkle to the history of the Kikai caldera, a huge depression that formed during a massive volcanic super-eruption about 6,300 or 7,300 years ago (the broad range has to do with different methods of dating the eruption). That eruption sent heated pyroclastic flow 50 miles (80 km) across the sea and spread ash up to 620 miles (1,000 km) away, said Yoshi Tatsumi, the author of a new study on the caldera’s inner workings, published today (Feb. 9) in the journalScientific Reports.

The system is still active, and it’s a relatively high-risk place for eruptive activity, said Erik Klemetti, a volcanologist at Denison University, who was not involved in the study. The volcano also blew its top in super-eruptions95,000 years ago and about 140,000 years ago. It occasionally burps ash and steam even in the modern day, with the last recorded eruption occurring between 2013 and 2014. [The 11 Biggest Volcanic Eruptions in History]

But because the caldera is hidden underwater, it’s hard to keep tabs on its activity. Tatsumi and his colleagues conducted multiple remotely-operated-vehicle dives to the caldera floor, south of Kyushu Island in the Japanese archipelago. They used sonar to map the caldera’s floor and shot small explosive charges into the seafloor to create seismic waves they could record and use to image the subsurface. The team also collected data on the water column’s chemistry and took rock samples from the looming dome in the center of the caldera.

This relief map shows the Kikai caldera: The inner and outer caldera are shown in solid lines. The blue diamonds indicate the diving sites of the remotely operated vehicle (ROV).

This relief map shows the Kikai caldera: The inner and outer caldera are shown in solid lines. The blue diamonds indicate the diving sites of the remotely operated vehicle (ROV).

Credit: Tatsumi et al., Scientific Reports, doi:10.1038/s41598-018-21066-w

The findings proved that the dome was, in fact, built up from lava, specifically a form of lava called rhyolite — some 8 trillion gallons (32 cubic kilometers) of it. This dome could have formed anytime since the last eruption, Klemetti said, so it isn’t clear how new it is. However, Tatsumi and his colleagues found that its chemical composition is different than the lava ejected from the caldera during the last super-eruption. This finding suggests that a new magma system formed after the eruption, Tatsumi told Live Science.

“The post-caldera activity, at least [at] this caldera, is regarded as the preparation stage to the next super-eruption, not as the calming-down stage from the previous super- eruption,” he said.

That doesn’t mean an eruption is imminent, but that the volcanic system that underpins the caldera has been changing and evolving over the millennia, the researchers reported. It’s interesting to see that the lava dome apparently originates from a different part of the magmatic system (underground chambers of molten rock) than the last super-eruption’s lavas, Klemetti said. [50 Amazing Facts About Volcanoes]

The best way to be sure the dome has a separate origin would be to test the minerals in the lavas and to find out when they formed, whether before the caldera-forming super-eruption, around the same time or after, Klemetti said. Tatsumi and his team plan to look deeper under the caldera. Given the giant size of the lava dome, there could be a large magma reservoir under the surface, Tatsumi said. The team plans to use subsurface imaging to look for that reservoir and describe it if it exists.

Original article on Live Science

Lava Gulps Down GoPro Camera, Which Records the Entire, Fiery Affair


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Lava Gulps Down GoPro Camera, Which Records the Entire, Fiery Affair

 https://www.livescience.com/61085-lava-engulfs-gopro-camera.html

The internet is awash with extreme videos, but footage of lava barreling toward and then melting the lens of a GoPro camera may be one of the hottest (literally) recordings online.

The fiery affair happened on Aug. 10, 2016, when Kilauea EcoGuides tours owner and lead guide Erik Storm took a group of tourists from San Francisco to Hawai’i Volcanoes National Park, according to National Geographic. The video resurfaced this month after Erez Marom, an Israeli photographer, accidently melted a drone camera when he flew it too close to lava flows in Hawaii, renewing interest in flaming-hot lava footage.

Storm captured the recording when he showed the tour group a fast-moving lava flow in the park that day. Storm put his GoPro Hero4 Black camera into a crevice to capture a recording of the molten rock, but he made what he now calls “a $400 mistake” — he didn’t pull out the camera in time, National Geographic reported. [50 Amazing Volcano Facts]

At least Storm has a good excuse for losing his GoPro to a molten blob. He was busy telling the tourists a story about Pele, the Polynesian fire goddess, he told National Geographic. After the scorching incident, he set to work retrieving the camera.

Don't drop your GoPro in the searing lava.
Don’t drop your GoPro in the searing lava.

Credit: Shutterstock

“I had a geologist rock hammer with me, and that is how I was able to get it out of the now cooling rock,” Storm wrote on Storyful, a video site. “When I got home, I hammered all the hardened rock off of the camera and was amazed to see the blue Wi-Fi light still blinking!”

Amazingly, the camera could still turn on, although the lens had melted, rendering it unusable. “The SD [secure digital] card popped right out and the footage was intact,” he told Storyful. “At the end of the video, you can see me with the rock hammer.”

It’s no wonder the lava melted Storm’s camera. Crawling, dark-red lava on Hawaii can reach temperatures of 895 degrees Fahrenheit (479 degrees Celsius), according to the U.S. Geological Survey (USGS), Live Science previously reported.

Bright-red lava flows are even hotter, reaching upward of 1,165 degrees F (629 degrees C), and glowing, orange lava indicates the molten rock is a steaming 1,600 degrees F (871 degrees C) or so, Live Science reported.

Despite the great footage, Storm doesn’t recommend that other people mess with lava: Many native Hawaiians consider lava to be sacred.

“No one should ever poke the lava with anything, cook with the lava orthrow anything into or in front of the flowing lava to ‘see what happens,'” Storm told Storyful. “I respect the place where I work to the fullest and work hard to make sure people understand that this is a very sacred place that commands respect.”

Original article on Live Science.

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Massive Calved Iceberg Comes into View as Antarctic Sun Rises


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Massive Calved Iceberg Comes into View as Antarctic Sun Rises

Massive Calved Iceberg Comes into View as Antarctic Sun Rises
Instruments aboard the Landsat 8 satellite captured these visible and thermal images on Sept. 16, 2017, of the A68 iceberg that snapped off Antarctica’s Larsen C Ice Shelf.

Credit: NASA Earth Observatory

As the sun rises above the Antarctic horizon after the long, dark austral winter, scientists are getting a better look at the Delaware-size iceberg that sheared off from the frozen continent’s Larsen C ice shelf in July.

With the illumination from the sun’s rays, new satellite images have captured the iceberg, dubbed A68, and the motley assortment of ice and water surrounding it, in impressive detail. In the coming months and years, scientists will be poring over such images to watch the progression of the iceberg and its parent ice shelf.

The researchers said they also hope to study the area up close, to examinedetails of the seafloor that have been blocked by ice for hundreds of yearsand to learn how such a massive shift could alter the local ecosystem. [In Photos: Antarctica’s Larsen C Ice Shelf Through Time]

“It’s obviously a completely different physical environment once the ice is gone,” Susie Grant, a marine biogeographer with the British Antarctic Survey, told Live Science.

Keeping tabs on the iceberg, the ice shelf and the ecosystem in the coming years could also help scientists better understand how other major ice shelves might respond to a warming world, according to Grant.

Scientists have watched for several years as a rift slowly propagated its way across the Larsen C ice shelf, a platform of ice that extends out from the coast and floats atop the ocean. After a couple of surges in 2016 and earlier this year, the rift finally reached the edge of the ice shelf and calved off the iceberg.

Snapshot of the rift in the Larsen C on Nov. 10, 2016.

Credit: John Sontag/NASA

But with the sun below the Antarctic horizon, researchers could monitor the event only with thermal imagery and radar, according to NASA’s Earth Observatory.

“When it did finally break off, it was just sort of these tantalizing” glimpses, Grant said.

Once the sun re-emerged in August, more satellite views started streaming in ¾ and they haven’t disappointed. The “satellite images are extraordinary,” Grant said. “To see something of that scale moving across the water.”

In mid-September, NASA’s Terra satellite and the Landsat 8 satellite captured shots of the iceberg in visible light and of the surrounding area in infrared wavelengths of light. The images reveal exciting details, like the wrinkly-looking rifts that stretch across parts of the iceberg and the mixture of open water and ice surrounding it. [Earth from Above: 101 Stunning Images from Orbit]

An instrument onboard the Terra satellite captured this image of the A68 iceberg on Sept. 11, 2017.

An instrument onboard the Terra satellite captured this image of the A68 iceberg on Sept. 11, 2017.

Credit: NASA Earth Observatory

In the psychedelic thermal image, the cold iceberg and ice shelf appear a ghostly white, while the relatively warmer sea ice shows up in shades of purple, and the even warmer (though still sub-freezing) open water pops out in yellow. Bluer shades show the mixture of ice called mélange, which can include snow, sea ice, bits of ice that fell from the sides of the rift and something called marine ice, which forms along the underside of the floating ice, said Ala Khazendar, a scientist with NASA’s Jet Propulsion Laboratory who uses radar to study polar ice.

The images also show how much the iceberg has moved away from its parent ice shelf. So far, it has been progressing at a steady clip, but how fast it might continue to move is unclear and depends on several factors: winds and ocean currents, as well as whether there are any bumps or ridges on the seafloor that the iceberg might get stuck on, Khazendar said.

If it does get stuck, he said, that will tell scientists something about the topography of the seafloor, which they had no way of viewing before the calving event, Grant said.

That seafloor and the water above it are also being exposed to sunlight for the first time in at least hundreds of years, and this could have major impacts on the local ecosystem, Grant said. For instance, ocean life at the water’s surface could suddenly ramp up in productivity. The newly opened area could also see species moving in from neighboring regions, she said. [Antarctica Photos: Meltwater Lake Hidden Beneath the Ice]

The ecosystem will be “potentially dramatically changed” by the calving event, Grant said, though it’s “impossible to know anything about that until we can get down and visit.”

The British Antarctic Survey and other groups are planning scientific cruises to get an up-close look at the changes to the region, and the sooner that happens the better, so they can establish a baseline before major changes occur, Grant said. Sediment cores drilled from the ocean floor will help scientists establish how long the area has been covered by ice, and sampling of the water will tell them how the temperature and salt content may be changing and what creatures live there, she said.

Those efforts are helped by an international agreement by the Commission for the Conservation of Antarctic Marine Living Resources, which has 25 international members, to designate the area around the ice shelf as a protected area so that activities like commercial fishing won’t hamper scientific work, Gizmodo reported. This is the first time there has been such a designation, Grant said.

“I think that was a really important step,” she said. “We were really pleased to have managed to get that.”

In the meantime, scientists will glean what information they can from satellite images and airborne observations made by NASA’s IceBridge program, which is gearing up for the Antarctic summer season, Khazendar said.

Researchers will be watching to see if the remaining ice shelf begins to flow faster in response to the iceberg’s loss, he said, and how the iceberg melts and potentially breaks up into smaller pieces (one such piece already broke off later in July).

“We still need to collect data and analyze them in order to understand how the Larsen C ice shelf is going to react to this event,” Khazendar said.

There are concerns that the massive calving event could mark a turning point for the glacier, sending it toward a global warming-fueled collapse like those suffered by its northern neighbors, Larsen A and Larsen B, in 1995 and 2002, respectively. But whether that will happen isn’t yet clear, and the ice shelf could recover from the calving event, as these events do happen naturally, Khazendar said.

“It will take us some time before we have some clearer answers,” he said.

How Larsen C responds could also give scientists a better idea of how other major ice shelves around Antarctica will respond to the warming waters that are lapping away at the shelves’ undersides and causing the glaciers that feed into shelves to flow faster out to the ocean, raising sea levels.

“It could teach us a lot about the fate of other large ice shelves in Antarctica,” Khazendar said

Studying the region could also “improve our understanding of how ecosystems might respond to the impacts of climate change,” Grant said.

Original article on Live Science.

These Stunning 3D Images Reveal How a Massive Greenland Glacier Has Changed


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These Stunning 3D Images Reveal How a Massive Greenland Glacier Has Changed

Watching a glacier

Credit: Jefferson Beck/NASA Goddard