Jan 3, 2025 06:51 PM
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Volcanic activity beneath Yellowstone's massive caldera could be on the move
https://www.sciencealert.com/volcanic-ac...n-the-move
INTRO: Volcanic activity bubbling away beneath the Yellowstone National Park in the US appears to be on the move.
New research shows that the reservoirs of magma that fuel the supervolcano's wild outbursts seem to be shifting to the northeast of the Yellowstone Caldera. This region could be the new locus of future volcanic activity, according to a team led by seismologist Ninfa Bennington of the US Geological Survey.
"On the basis of the volume of rhyolitic melt storage beneath northeast Yellowstone Caldera, and the region's direct connection to a lower-crustal heat source, we suggest that the locus of future rhyolitic volcanism has shifted to northeast Yellowstone Caldera," they write in their paper.
"In contrast, post-caldera rhyolitic volcanism in the previous 160,000 years has occurred across the majority of Yellowstone Caldera with the exclusion of this northeast region."
Yellowstone is one of the world's largest supervolcanoes; a vast, complex, dynamic region of Earth's crust that is both spectacularly beautiful and deeply dangerous.
In the past 2 million years, Yellowstone has undergone three huge, caldera-forming eruptions – those that create the cauldron-like basins on Earth's surface when a subterranean magma chamber empties and collapses in on the hollowed-out cavity. These huge eruptions have been interspersed with smaller eruptions... (MORE - details)
Ice cores finger obscure Pacific volcano as cause of 19th century climate disaster
https://www.science.org/content/article/...e-disaster
EXCERPT: At long last, the culprit has been unmasked in a report in the Proceedings of the National Academy of Sciences. A team led by volcanologist William Hutchison of the University of St. Andrews describes sulfur isotopes and glassy shards of ash deposited in ice core layers dated to 1831 that trace back to an obscure volcano in the remote Kuril Islands north of Japan’s Hokkaido Island.
Revealing the Zavaritskii volcano as the climate-altering perp “was a very nice piece of forensic work,” says Oppenheimer, who was not connected to the study.
The Zavaritskii eruption also offers a cautionary tale for today. “We’ve had this idea that the biggest eruptions that change climate tend to happen at low latitudes—eruptions like Pinatubo and Tambura,” Hutchison says. “But this shows that high-latitude eruptions can have very big impacts as well.”
After the Sun mysteriously dimmed in August 1831, the real misery began. Touring the Alps late that summer, composer Felix Mendelssohn wrote about having to endure “abysmal weather,” including heavy snows that “were completely unexpected,” Hutchison says. “Huge hailstones destroyed crops in Europe.” Decreased rainfall during the Indian monsoon led to crop failures and a devastating famine in the eastern Indian state of Madras in 1832 and 1833 that killed about 150,000 people. About twice as many died in a famine that gripped northeastern Japan from 1832 to 1837.
Volcanologists have for decades had proof that a major eruption occurred somewhere in 1831. Like other significant eruptions, the blast shows up as an easily dated sulfur spike in ice cores taken from Greenland and Antarctica. The sulfur-laden aerosols blocked sunlight, tamping down temperatures by as much as 1°C over 2 years, according to historical records.
And thicker sulfur deposits in Greenland cores pointed to an eruption in the midlatitudes of the Northern Hemisphere that released about 13 teragrams of sulfur into the stratosphere—comparable to that of the planet-cooling 1991 eruption of Mount Pinatubo in the Philippines.
The 1831 eruption is intriguing also because it and several other major eruptions occurred near the end of the Little Ice Age, a 500-year-long big chill felt across the globe. This cluster of eruptions includes one of the biggest in recorded history: that of Indonesia’s Mount Tambora in 1815, which also cooled the planet and led to widespread harvest failures. These eruptions “may have prolonged the Little Ice Age,” Hutchison says. (The volcano responsible for one of the larger eruptions in this grouping—one or more blasts in 1808 or 1809, between Zavaritskii and Tambora in size—remains a mystery.) (MORE - missing details)
https://www.sciencealert.com/volcanic-ac...n-the-move
INTRO: Volcanic activity bubbling away beneath the Yellowstone National Park in the US appears to be on the move.
New research shows that the reservoirs of magma that fuel the supervolcano's wild outbursts seem to be shifting to the northeast of the Yellowstone Caldera. This region could be the new locus of future volcanic activity, according to a team led by seismologist Ninfa Bennington of the US Geological Survey.
"On the basis of the volume of rhyolitic melt storage beneath northeast Yellowstone Caldera, and the region's direct connection to a lower-crustal heat source, we suggest that the locus of future rhyolitic volcanism has shifted to northeast Yellowstone Caldera," they write in their paper.
"In contrast, post-caldera rhyolitic volcanism in the previous 160,000 years has occurred across the majority of Yellowstone Caldera with the exclusion of this northeast region."
Yellowstone is one of the world's largest supervolcanoes; a vast, complex, dynamic region of Earth's crust that is both spectacularly beautiful and deeply dangerous.
In the past 2 million years, Yellowstone has undergone three huge, caldera-forming eruptions – those that create the cauldron-like basins on Earth's surface when a subterranean magma chamber empties and collapses in on the hollowed-out cavity. These huge eruptions have been interspersed with smaller eruptions... (MORE - details)
Ice cores finger obscure Pacific volcano as cause of 19th century climate disaster
https://www.science.org/content/article/...e-disaster
EXCERPT: At long last, the culprit has been unmasked in a report in the Proceedings of the National Academy of Sciences. A team led by volcanologist William Hutchison of the University of St. Andrews describes sulfur isotopes and glassy shards of ash deposited in ice core layers dated to 1831 that trace back to an obscure volcano in the remote Kuril Islands north of Japan’s Hokkaido Island.
Revealing the Zavaritskii volcano as the climate-altering perp “was a very nice piece of forensic work,” says Oppenheimer, who was not connected to the study.
The Zavaritskii eruption also offers a cautionary tale for today. “We’ve had this idea that the biggest eruptions that change climate tend to happen at low latitudes—eruptions like Pinatubo and Tambura,” Hutchison says. “But this shows that high-latitude eruptions can have very big impacts as well.”
After the Sun mysteriously dimmed in August 1831, the real misery began. Touring the Alps late that summer, composer Felix Mendelssohn wrote about having to endure “abysmal weather,” including heavy snows that “were completely unexpected,” Hutchison says. “Huge hailstones destroyed crops in Europe.” Decreased rainfall during the Indian monsoon led to crop failures and a devastating famine in the eastern Indian state of Madras in 1832 and 1833 that killed about 150,000 people. About twice as many died in a famine that gripped northeastern Japan from 1832 to 1837.
Volcanologists have for decades had proof that a major eruption occurred somewhere in 1831. Like other significant eruptions, the blast shows up as an easily dated sulfur spike in ice cores taken from Greenland and Antarctica. The sulfur-laden aerosols blocked sunlight, tamping down temperatures by as much as 1°C over 2 years, according to historical records.
And thicker sulfur deposits in Greenland cores pointed to an eruption in the midlatitudes of the Northern Hemisphere that released about 13 teragrams of sulfur into the stratosphere—comparable to that of the planet-cooling 1991 eruption of Mount Pinatubo in the Philippines.
The 1831 eruption is intriguing also because it and several other major eruptions occurred near the end of the Little Ice Age, a 500-year-long big chill felt across the globe. This cluster of eruptions includes one of the biggest in recorded history: that of Indonesia’s Mount Tambora in 1815, which also cooled the planet and led to widespread harvest failures. These eruptions “may have prolonged the Little Ice Age,” Hutchison says. (The volcano responsible for one of the larger eruptions in this grouping—one or more blasts in 1808 or 1809, between Zavaritskii and Tambora in size—remains a mystery.) (MORE - missing details)