Mauna Loa: World’s largest active volcano erupts in Hawaii
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Hawaii officials have released a new map of the Mauna Loa eruption, revealing the areas currently under threat from lava spewing out of the world’s largest active volcano.
In a Monday night update, the US Geological Survey (USGS) said that no populated areas were under threat but that officials would provide updates if the situation changed.
While residents may not be at risk from the lava, the Hawaii Department of Health is warning the public about risks of air quality hazards such as vog conditions, ash in the air, and rising levels of sulfur dioxide.
Mauna Loa erupted for the first time in nearly four decades late on Sunday night, triggering dozens of earthquakes of more than 2.5 magnitudes on the Richter scale, one of them clocking in at 4.2.
According to the National Weather Service (NWS), the eruption on the state’s Big Island began at approximately 11.30pm local time on Sunday in Mokuaweoweo, the summit caldera of the volcano.
Footage from US Geological Survey (USGS) webcams at the summit captured fountains of lava spewing from a long fissure and spreading across the caldera floor.
Key Points
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In Pictures: Mauna Loa erupts
The largest subaerial volcano in both mass and volume, Mauna Loa has historically been considered one of the largest volcano on Earth, dwarfed only by Tamu Massif
(Jetter McTedder / SWNS)
Lava flowing on the northeast rift zone of Mauna Loa
(US Geological Survey/AFP via Get)
Johanna Chisholm29 November 2022 12:10
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Latest US Geological Survey update
The latest update from the US Geological Survey (USGS), reported at 2.55am Pacific Standard Time, said that the federal agency does “not expect upper fissures to reactivate” but noted that additional fissures could open along the Northeast Rift Zone below the current location, which means that lava flows can continue to travel downslope.
“There is no active lava within Moku’āweoweo caldera, and there is no lava erupting from the Southwest Rift Zone. We do not expect any eruptive activity outside the Northeast Rift Zone,” the update read. “No property is at risk currently. There is a visible gas plume from the erupting fissure fountains and lava flows, with the plume primarily being blown to the Northwest.”
Read the full update here.
Johanna Chisholm29 November 2022 11:50
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Hawaii officials warn about risks of air quality hazards
The Hawaii Department of Health is warning the public about risks of air quality hazards such as vog conditions, ash in the air, and rising levels of sulfur dioxide – following the eruption of Mauna Loa.
As of 2pm local time on Monday, permanent air quality monitoring stations across the state reported that air quality remains normal.
However, conditions are changing rapidly, and poor air quality may be very localised, the agency warned.
The agency released the following guidance for residents in the event of voggy conditions:
Reduce outdoor activities that cause heavy breathing. Avoiding outdoor activity and exercise during vog conditions can reduce exposure and minimize health risks. This is especially important for sensitive groups such as children, the elderly, and individuals with pre-existing respiratory conditions including asthma, bronchitis, emphysema, and chronic lung and heart disease.People with asthma or a chronic respiratory disease should always have medications available. Daily prescribed medications should be taken on schedule.People experiencing health effects should contact their medical provider as soon as possible if any symptoms develop, as respiratory conditions might worsen rapidly in heavy sulfur dioxide or vog conditions.Stay indoors and close windows and doors. If an air conditioner is used, set it to recirculate. If you need to move out of an impacted area, turn on the car’s air conditioner and set it to recirculate.Face masks (surgical, cloth, KF94, KN95, N95) do not provide protection from sulfur dioxide or vog. However, they can be effective in outdoor environments in reducing inhaled hazardous particulates associated with falling ash and Pele’s hair.Do not smoke and avoid second-hand smoke.Drink plenty of fluids to avoid dehydration.
Rachel Sharp29 November 2022 11:30
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How do scientists monitor Mauna Loa?
The Hawaiian Volcano Observatory has more than 60 GPS stations on Mauna Loa taking measurements to estimate the location and the amount of magma accumulating beneath the surface.
Scientists use tiltmeters to track long-term changes in the tilting of the ground, helping them identify when the ground is swelling or deflating. A rapid change in tilt can indicate when an eruption will occur.
There’s also a thermal webcam at Mauna Loa’s summit that will identify the presence of heat. And satellite radar can keep track of ground swelling and deflation.
Rachel Sharp29 November 2022 11:00
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Hawaii officials have released a new map of the Mauna Loa eruption, revealing the areas currently under threat from lava spewing out of the world’s largest active volcano.
In a Monday night update, the US Geological Survey (USGS) said that no populated areas were under threat but that officials would provide updates if the situation changed.
“The Mauna Loa eruption has focused on the NE Rift Zone. No populated areas are currently threatened, so the HVO social media team will sign off for the night,” the department tweeted.
“We’ll break in if there are any major changes and will be back in the morning. Latest map and morning photo attached.”
Latest map of eruptive activity from Mauna Loa
(USGS)
Rachel Sharp29 November 2022 10:38
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How are volcanic eruptions impacted by climate change?
While the eruption of Mauna Loa is a rare occurrence, the climate crisis could lead to more volcanic activity, some scientists say.
The greenhouse gas emissions heating the planet are melting glaciers and in turn destabilizing mountains, creating conditions for volcanic eruptions that were previously restrained.
Oliver O’Connell29 November 2022 08:50
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Why didn’t Mauna Loa explode like Mount St Helens?
Fifty-seven people died when Washington state’s Mount St Helens erupted in 1980 and blasted more than 1,300ft (400m) off the top of the mountain. Steam, rocks and volcanic gas burst upward and outward. A plume of volcanic ash rose over 80,000ft (24,384m) and rained down as far as 250 miles (400km) away.
Hawaii volcanoes like Mauna Loa tend not to have explosion eruptions like this.
That’s because their magma is hotter, drier and more fluid, said Hannah Dietterich, a research geophysicist at the US Geological Survey’s Alaska Volcano Observatory.
The magma in Mount St Helens tends to be stickier and traps more gas, making it much more likely to explode when it rises.
The gas in the magma of Hawaii’s volcanoes tends to escape, and so lava flows down the side of their mountains when they erupt.
Hawaii’s volcanoes are called shield volcanoes because successive lava flows over hundreds of thousands of years build broad mountains that resemble the shape of a warrior’s shield.
Shield volcanos are also found in California and Idaho as well as Iceland and the Galapagos Islands. Alaska’s Wrangell-St Elias National Park has eight shield volcanoes including Mount Wrangell.
Volcanoes like Mount St. Helens are called composite or stratovolcanoes. Their steep, conical slopes are built by the eruption of viscous lava flows and rock, ash and gas. Japan’s Mount Fuji is another example of a composite volcano.
Oliver O’Connell29 November 2022 06:50
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Watch: World’s largest active volcano erupts in Hawaii for first time in almost 40 years
Mauna Loa, the largest active volcano on the planet, has erupted for the first time in almost 40 years.
Footage shows the sky glowing red as the volcano erupted on Hawaii‘s Big Island.
Dozens of earthquakes, some of more than 2.5 on the richter scale, were triggered by the eruption.
The last eruption at Mauna Loa occurred in 1984.
Mauno Loa: World’s largest active volcano erupts for first time in almost 40 years
Mauna Loa, the largest active volcano on the planet, has erupted for the first time in almost 40 years. Footage shows the sky glowing red as the volcano erupted on Hawaii’s Big Island. The National Weather Service (NWS) said that the eruption began at 11:30pm local time on Sunday, 27 November. Dozens of earthquakes, some of more than 2.5 on the richter scale, were triggered by the eruption. The last eruption at Mauna Loa occurred in 1984. Click here to sign up for our newsletters.
Oliver O’Connell29 November 2022 04:50
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What happens next?
Each eruption since 1843 started at Mauna Loa’s summit. Half the time, the volcano later also began erupting from vents at lower elevations. The other half of the time it only erupted in the summit caldera.
Scientists can’t tell far in advance when and where Mauna Loa will open new vents and erupt.
Vents generally form along the volcano’s rift zone. That’s where the mountain is splitting apart, the rock is cracked and relatively weak and it’s easier for magma to emerge.
An eruption from vents on the southwest rift zone could hit residential communities, coffee farms or coastal villages on the west side of the island. Lava could reach homes in just hours or days.
The west side’s most populous town would be protected from any Mauna Loa eruption by the presence of another active volcano. The broad flanks of that volcano, Hualalai, sit between Mauna Loa’s southwest rift zone and Kailua-Kona and would block any lava heading toward the coastal community.
An eruption from the northeast rift zone could send lava toward the county seat of Hilo or other towns in East Hawaii. It could take lava weeks or months to reach populated areas on this side of the mountain.
Scott Rowland, a geologist at the University of Hawaii at Manoa, said there’s no pattern when it comes to where an eruption will occur.
“Just because the last one was on the northeast rift zone does not mean the next one will be down the southwest rift zone,” he said.
Oliver O’Connell29 November 2022 03:50
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Why doesn’t Mauna Loa erupt like is neighbour Kilauea
Kilauea is well-known for a 2018 eruption that destroyed 700 homes and sent rivers of lava spreading across farms and into the ocean. The eruption of Mauna Loa is different.
Mauna Loa’s eruptions differ from Kilauea’s in part because it is taller. It’s greater height gives it steeper slopes, which allow lava to rush down its hillsides faster than Kilauea’s.
It’s enormous size may allow it to store more magma, leading to larger lava flows when an eruption occurs.
Frank Trusdell, research geologist at the Hawaiian Volcano Observatory, which is part of the U.S. Geological Survey, said data indicates that Mauna Loa has a much larger magma reservoir than Kilauea, which may allow it to hold more lava and rest longer between eruptions than Kilauea.
Oliver O’Connell29 November 2022 02:50