Latest news with #volcanologists
The Independent
16 hours ago
- Climate
- The Independent
Volcanologist reveals exactly what happened at Mount Etna
On Monday morning local time, a huge cloud of ash, hot gas and rock fragments began spewing from Italy's Mount Etna. An enormous plume was seen stretching several kilometres into the sky from the mountain on the island of Sicily, which is the largest active volcano in Europe. While the blast created an impressive sight, the eruption resulted in no reported injuries or damage and barely even disrupted flights on or off the island. Mount Etna eruptions are commonly described as 'Strombolian eruptions' – though as we will see, that may not apply to this event. What happened at Etna? The eruption began with an increase in pressure in the hot gases inside the volcano. This led to the partial collapse of part of one of the craters atop Etna. The collapse allowed what is called a pyroclastic flow: a fast-moving cloud of ash, hot gas and fragments of rock bursting out from inside the volcano. Next, lava began to flow in three different directions down the mountainside. These flows are now cooling down. On Monday evening, Italy's National Institute of Geophysics and Volcanology announced the volcanic activity had ended. Etna is one of the most active volcanoes in the world, so this eruption is reasonably normal. What is a Strombolian eruption? Volcanologists classify eruptions by how explosive they are. More explosive eruptions tend to be more dangerous because they move faster and cover a larger area. At the mildest end are Hawaiian eruptions. You have probably seen pictures of these: lava flowing sedately down the slope of the volcano. The lava damages whatever it runs into, but it's a relatively local effect. As eruptions grow more explosive, they send ash and rock fragments flying further afield. At the more explosive end of the scale are Plinian eruptions. These include the famous eruption of Mount Vesuvius in 79AD, described by the Roman writer Pliny the Younger, which buried the Roman towns of Pompeii and Herculaneum under metres of ash. In a Plinian eruption, hot gas, ash, and rock can explode high enough to reach the stratosphere, and when the eruption column collapses, the debris falls to Earth and can wreak terrifying destruction over a huge area. What about Strombolian eruptions? These relatively mild eruptions are named after Stromboli, another Italian volcano, which belches out a minor eruption every 10 to 20 minutes. In a Strombolian eruption, chunks of rock and cinders may travel tens or hundreds of metres through the air, but rarely further. The pyroclastic flow from yesterday's eruption at Etna was rather more explosive than this, so it wasn't strictly Strombolian. Can we forecast volcano eruptions? Volcanic eruptions are a bit like weather. They are very hard to predict in detail, but we are a lot better than we used to be at forecasting them. To understand what a volcano will do in the future, we first need to know what is happening inside it right now. We can't look inside directly, but we do have indirect measurements. For example, before an eruption, magma travels from deep inside the Earth up to the surface. On the way, it pushes rocks apart and can generate earthquakes. If we record the vibrations of these quakes, we can track the magma's journey from the depths. Rising magma can also make the ground near a volcano bulge upwards very slightly, by a few millimetres or centimetres. We can monitor this bulging, for example, with satellites, to gather clues about an upcoming eruption. Some volcanoes release gas even when they are not strictly erupting. We can measure the chemicals in this gas, and if they change, it can tell us that new magma is on its way to the surface. When we have this information about what's happening inside the volcano, we also need to understand its 'personality' to know what the information means for future eruptions. Are volcanic eruptions more common than in the past? As a volcanologist, I often hear from people that it seems there are more volcanic eruptions now than in the past. This is not the case. What is happening, I tell them, is that we have better monitoring systems now, and a very active global media system. So we know about more eruptions – and even see photos of them. Monitoring is extremely important. We are fortunate that many volcanoes in places such as Italy, the United States, Indonesia and New Zealand have excellent monitoring in place. This monitoring allows local authorities to issue warnings when an eruption is imminent. For a visitor or tourist out to see the spectacular natural wonder of a volcano, listening to these warnings is all-important.
Gizmodo
21-05-2025
- Science
- Gizmodo
Monitoring Tree Leaves From Space Could Help Predict Volcanic Eruptions
Forecasting volcanic eruptions is difficult, but not impossible. By keeping an eye on features such as ground deformation, changes in gas emissions, and ground tremors, volcanologists can sometimes make successful predictions, which save countless lives. NASA and the Smithsonian Institution are now teaming up to monitor another volcanic harbinger, but from space: leaves. Scientists already knew that tree leaves can change color when a nearby volcano becomes more active, but this collaboration aims to observe the mechanism using satellite imagery. Given that there's no way to avoid volcanic eruptions, early warning systems are the only way to keep the public safe. 'Volcano early warning systems exist,' Florian Schwandner, a volcanologist and chief of the Earth Science Division at NASA's Ames Research Center, said in a NASA statement announcing the collaboration. 'The aim here is to make them better and make them earlier.' As magma rises toward the surface of the Earth before an eruption, it releases gases such as carbon dioxide and sulfur dioxide. In fact, in 2017, a monitoring network at a volcano in the Philippines—which Schwandner and his colleagues had previously upgraded to read carbon dioxide and sulfur dioxide emissions—enabled government researchers to forecast a major volcanic eruption. Thanks to mass evacuations, no lives were lost. Carbon dioxide emissions are one of the earliest signs that a volcano is waking up, but they are difficult to spot directly from space. Why would we want to see carbon dioxide emissions from space? Because otherwise, volcanologists have to trek to volcanoes in person to measure them directly—a task that can be difficult, expensive, and even dangerous. 'Volcanoes emit a lot of carbon dioxide,' said Robert Bogue, a volcanologist from McGill University. However, 'a volcano emitting the modest amounts of carbon dioxide that might presage an eruption isn't going to show up in satellite imagery,' he explained. Carbon dioxide does show up, however, in trees' foliage, making it greener and more lush. As such, the NASA and Smithsonian collaboration is bringing together volcanologists, botanists, and climate scientists to investigate how researchers can use trees to monitor volcanic activity. 'The whole idea is to find something that we could measure instead of carbon dioxide directly,' Bogue explained, 'to give us a proxy to detect changes in volcano emissions.' 'There are plenty of satellites we can use to do this kind of analysis,' confirmed Nicole Guinn, a volcanologist from the University of Houston. Guinn has previously monitored trees near Italy's Mount Etna volcano using satellite imagery. The approach has constraints, however. For example, some volcanoes aren't close enough to trees for satellite images to be useful, and different trees can experience different responses to carbon dioxide. Furthermore, fires, weather events, and plant diseases can make satellite data difficult to interpret. But the truth is that no single feature can perfectly predict volcanic activity. 'There's not one signal from volcanoes that's a silver bullet,' Schwandner said. 'And tracking the effects of volcanic carbon dioxide on trees will not be a silver bullet. But it will be something that could change the game.'
Yahoo
18-05-2025
- Science
- Yahoo
The day the sky darkened: Mount St. Helens erupted in Washington State 45 years ago
On May 18, 1980, the United States experienced the deadliest and most destructive volcanic eruption in its history. After more than two months of rumbling, Washington State's Mount St. Helens erupted with a force equivalent to as much as 50 megatons of TNT. The massive blast and subsequent landslides, flooding and ash cloud killed 57 people, caused more than $1 billion in damages, destroyed at least 200 homes and was heard more than 200 miles away. The resulting scorching ash cloud reached as high as 16 miles into the atmosphere, darkening the sky and causing homes and businesses as much as 300 miles away to close. A massive wave of melted snow, ice, ash and pumice raced down the sides of the mountain, reaching up to 60 miles away and crushing homes, forests, bridges and roadways in its path. Once known as the Mt. Fuji of America, the eruption came after the majestic cone-shaped volcano had lain dormant for 123 years. The eruption, observed in detail by hundreds of geologists, volcanologists and ecologists, added immensely to human knowledge about vulcanism, a silver lining to the devastation it caused. It led to better preparation in volcanic areas, significant new scientific study and awareness of volcanic systems and the creation of five USGS volcano observatories in volcanically active portions of the United States – Alaska, California, the Cascade mountains (Washington, Oregon, Idaho) and Hawaii. Here's how the eruption unfolded: Scientists observed magma building inside the volcano, creating a visible bulge on its northern side. A series of small earthquakes began on March 16, reaching several hundred by the end of the month. On March 27, the volcano experienced its first major eruption since the mid-1800s. A steam explosion blasted a 250-foot wide crater through the ice cap on the summit, covering the snow-clad southeastern portion of the mountain with dark ash. A 15-miles radius around the area was evacuated and roadblocks put in place. By April 22, more than 10,000 earthquakes had occurred on the mountain and the northern flank bulged out by 450 feet, growing six-and-a-half feet per day, as molten magma rose up inside the volcano. At 8:32 a.m., a magnitude 5.1 earthquake shook the mountain, setting off an enormous landslide on the volcano's northern flank. An estimated 3.3 billion cubic yards of material sloughed off the mountain, the largest debris avalanche in Earth's recorded history, according to the U.S. Geological Survey. With the loss of all that material, the boiling, highly pressurized magma underneath was released. As NASA put it, "When the mountain collapsed, it was like uncorking a bottle of champagne: hot rocks, ash, gas, and steam exploded upward and outward to the north." Within 15 minutes, a cloud of tephra (ash, rocks and cooling magma) rose more than 15 miles into the atmosphere. The blast, avalanche and pyroclastic flows destroyed more than 230 square miles of forest. A total of 57 people died, most from asphyxiation after inhaling hot ash. They included locals who refused to leave despite warnings as well as residents, volcanologists and journalists who thought they were observing from a safe distance. Avalanches of hot ash, pumice and gas as well as volcanic mudflows from all the melted snow and ice spread for miles, destroying 27 bridges, more than 200 homes, 185 miles of roads and 15 miles of railway. River valleys were smothered and the path of the Toutle River was altered. To this day it remains full of sediment. The area was so completely devastated that when viewing it, then-President Jimmy Carter said, "Someone said this area looked like a moonscape. But the moon looks more like a golf course compared to what's up there." Communities hundreds of miles away were covered in ash from the eruption. The corrosive ash, composed of rock, mineral crystals and volcanic glass, snarled air travel, closed airports, shuttered schools and businesses and damaged machinery and automobiles. People wore bandanas over their mouths when outside to avoid breathing it in. When they tried to wash it off their cars, it scraped the paint. Within two weeks, the thinning ash cloud had circled the globe. A new lava dome, recorded by USGS and NASA, began to rise in the middle of the crater formed by the 1980 eruption. Earthquake activity renewed in September. Swarms of small earthquakes shook the mountain and small steam and ash explosions were observed in 2005. By 2008 millions of cubic yards of lava had erupted onto the crater floor, refilling about 7% of the crater. By the end of 2008 the mountain had once again calmed down. The aftermath of the 1980 eruption continued. Warm weather and melting snow led to a landslide of volcanic debris that washed out the Spirit Lake Outlet Bridge and damaged portions of State Road 504 in Washington, blocking access to the Johnson Ridge Observatory, which remains closed. This article originally appeared on USA TODAY: Mount St. Helens erupted 45 years ago: Here's what happened
Yahoo
13-05-2025
- Climate
- Yahoo
Philippine volcano briefly erupts, belching ash plume into the sky
MANILA, Philippines (AP) — A restive volcano in central Philippines briefly erupted Tuesday, spewing a 4.5-kilometer (2.8-mile) ash plume and debris into the sky as its rumblings were heard nearby. The Philippine Institute of Volcanology and Seismology said a moderately explosive eruption occurred at the summit crater of Kanlaon Volcano before dawn, lasting five minutes based on seismic and infrasound data. 'The eruption generated a greyish voluminous plume that rose approximately 4.5 kilometers above the vent before drifting to the southwest,' the institute's bulletin added. Ash fell in at least nine villages southwest of the volcano on Negros island, but no injuries or damage was reported. A level 3 alert -- out of a scale of five -- that was put in place during Kanlaon's eruption in December remained unchanged, with officials keeping a 6-kilometer (3.7-mile) danger zone off limits. The alert means the volcano is in a state of magmatic unrest, with increased chances of short-lived, moderately explosive eruptions that could generate volcanic hazards. Kanlaon also briefly erupted in April. Its eruption in December prompted the evacuation of thousands of villagers to emergency shelters as the volcano continued showing signs of restiveness. The 2,435-meter (7,988-foot) volcano is one of the country's 24 most active volcanoes. In 1996, three hikers were killed near the peak and several others were later rescued when Kanlaon erupted without warning, officials said then. The Philippines is located in the so-called Pacific 'Ring of Fire,' a region prone to earthquakes and volcanic eruptions. The archipelago is also lashed by about 20 typhoons and storms a year, making it one of the world's most disaster-prone countries.
