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These lava lakes drained catastrophically—and scientists caught it in action – National Geographic

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When Yves Moussallam trekked around Vanuatu’s Ambrym volcano in the winter of 2018, the ground was blanketed in green, and five incandescent lakes of molten rock burbled in the volcano’s caldera. Just two weeks later, though, he found himself in a landscape devoid of color. Gray ash coated each rock and crevice, and the lakes sat empty, their lava vanished like water swirled down a drain.

“It looked like everything was in black-and-white,” says Moussallam, a volcanologist at Columbia University who is also associated with France’s Laboratoire Magmas et Volcans. “The whole caldera area had completely changed.”

This transformation came in the wake of an extraordinary eruption that surprised scientists with its progression. While some of the lava spurted up from nearby cracks, the vast majority moved underground—a slug of magma big enough to fill 160,000 Olympic swimming pools. As the team reports in Scientific Reports, the process cracked the earth, sending coasts soaring into the air, and brought lava burbling up onto the ocean floor.

“It’s kind of a negative eruption, in a way,” says volcanologist Clive Oppenheimer of the University of Cambridge, who was not on the study team. “It’s not stuff coming out of the ground, it’s the magma migrating beneath the ground.”



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Lava roils in one of Ambrym’s lakes before the 2018 eruption. Lava lakes can act like windows to the deep, giving clues to what’s happening deep beneath the surface.

Photograph by Yves Moussallam

The new study provides a rare and detailed portrait of Ambrym’s activity above and below, which can help geologists unravel the myriad processes that contribute to volcanic activity.

“As volcanologists, we’re always trying to understanding what’s going on kilometers beneath our feet, and that can be difficult because we don’t have direct access to the magmatic reservoirs,” says study coauthor Tara Shreve, a Ph.D. candidate at the Institut de Physique du Globe de Paris. But the new study combines an array of clues to better understand the events conspiring deep underground, providing important details about Ambrym’s volcanic capabilities—and the variety of hazards such eruptions can present.

“It’s not like a lab science, where you can go and do the same experiment over and over and over again,” says Emily Montgomery-Brown, a geodesist at U.S. Geological Survey’s California Volcano Observatory who was not part of the study team. “We learn so much from every single eruption.”

A chance sighting

Moussallam initially ventured to Ambrym as part of a study analyzing the prodigious gasses puffing from volcanoes across the Vanuatu arc, a project funded by the National Geographic Society. They monitored gasses at three of Ambrym’s lava lakes before heading on their way. Two weeks later, they were prepping for their flight back home from Vanuatu’s capital city, Port Vila, when they got the news: Ambrym was erupting.

The team caught a helicopter back to the island and gaped at the difference. The molten lakes had disappeared. A lava flow cooled in the distance. Nearby trees crackled with flames. Connecting the dots, they at first assumed that magma had burst to the surface, draining the system.

“We thought that was the story,” Moussallam says. But, as they later discovered, the eruption was still playing out deep under their feet.

Intense earthquakes began rocking the island, and hefty fractures cut through the ground, forming steps in the landscape. In the coastal village of Pamal, eight miles from the caldera’s rim, roads were cleaved in two and houses were thrust feet into the air. The ground split under one building, leaving part of the structure hanging in mid-air.

“Clearly something was still going on,” Moussallam says. “It was really surprising it was so far away from where the eruption had begun.”

Pairing satellite analyses with on-the-ground observations, the team later learned that this was all part of a multi-day saga, as 14 billion cubic feet of magma shifted eastward, squeezing through deep cracks under the island for more than 10 miles.

This sudden addition of subsurface material shoved the coasts upward some six and a half feet, exposing a vast expanse of coral and red algae to deadly sunlight, says Géoazur’s Bernard Pelletier, a study coauthor who surveyed the coasts post-eruption. The loss was also felt at the volcano’s gaping summit caldera, which sunk by roughly eight feet.

On December 18, four days after the eruption began, volcanic pumice washed up on the island’s eastern shore—likely the result of magma finally oozing out from the subsurface into coastal waters.

Peering inside Earth

This type of draining through deep fissures in the ground, known as rift zone volcanism, is not unheard of, but Ambrym is an unlikely candidate.

Rift zone volcanism is most common in places where tectonic plates are separating, and extension in the crust pulls the land apart. Take, for example, the deep fissures found in Iceland’s volcanoes, which frequently line up with the pair of tectonic plates separating beneath the island country. Rift volcanism is also responsible for much activity at Kilauea which, along with the underlying flanks of Mauna Loa, is slowly sliding into the sea, Montgomery-Brown explains.

Volcanoes 101

About 1,500 active volcanoes can be found around the world. Learn about the major types of volcanoes, the geological process behind eruptions, and where the most destructive volcanic eruption ever witnessed occurred.

By contrast, Vanuatu sits near the tectonic collision zone between the Pacific and Indo-Australian plates, which compresses the region. However, the latest analysis suggests that Vanuatu’s pressure-packed position isn’t a problem. The rift that drained the magma is oriented so that the two sides separate in the direction of least compression, allowing the fracture to inflate “like a whoopee cushion,” Montgomery-Brown says. The team’s modeling suggests that the pocket of magma inside the rift likely bulged more than 13 feet across in some spots.

One lingering curiosity is what happened to the volcano’s gas, says Philipson Bani, a volcanologist at France’s Institute of Research for Development who was not on the study team. Ambrym has been one of the greatest natural emitters of carbon dioxide and other volcanic gasses around the world for many years. How it maintained such activity remains a mystery, he says. Then the eruption happened and, almost overnight, the gaseous factory seemed to turn off.

“How can you just shut off the pipe?” Bani says. “On Ambrym, we have more and more and more gas in the past, and then boom. It stops.”

Magmatic budgets

Still more clues to Ambrym’s eruption may continue to emerge, Moussallam notes. He’s currently looking into the chemistry of the lavas, which seem to be of at least two different compositions, likely originating from separate reservoirs. While more research is required to confirm the find, it hints that the eruption’s ignition spark might have been the formation of a new connection between the pair of reservoirs.

Detailed analyses of volcanic systems, like this latest Ambrym paper, are important in understanding the mechanics of volcanic eruptions. Such work might even help give clues to a volcano’s magmatic budget, revealing how much molten rock might be available for future eruptions, Mongomery-Brown says.

Just months before Ambrym drained, Kilauea’s lava lakes in Hawaii were making their own fiery exit from deep cracks on the volcano’s flanks. But Montgomery-Brown and her colleagues recently found that Kilauea’s extensive eruption and the collapse of its summit crater came from the release of a mere 11 to 33 percent of its shallow magma reservoir. The find sparked many questions, including why the eruption stopped at all.

In these ways, both eruptions provide a vital look into the dynamic and varied ways volcanoes work, says Matthew Patrick, a geologist with the United States Geological Survey’s Hawaiian Volcano Observatory, who was not involved with the new study.

“Now, for both volcanoes we’re in this recovery phase,” he says, “and the big question is, What’s next?”

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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