Tag Archives: volcano eruption

Stunning satellite observations show Tonga eruption effects in unprecedented detail

The Hunga Tonga-Hunga Ha‘apai volcano erupted on January 14, causing massive shockwaves and tsunamis that lead to 3 deaths and caused substantial damage to the Tongan Islands. Thanks to satellite imagery, researchers were able to observe this process in stunning detail. Here are some of these observations.

Ashes and cooling

The eruption released vast quantities of aerosols into the atmosphere. These particles reached the stratosphere, some 9 miles (15 km) above the surface. The stratosphere is a dry part of the atmosphere without clouds or humidity — so everything that reaches the stratosphere has little to interact with and is easily observable from above. 

The ashes from volcanoes consist largely of sulfur dioxide; once this sulfur dioxide reaches the atmosphere, it filters out some of the solar rays, producing a cooling effect. This effect can be quite powerful. Nearly 31 years ago, the Pinatubo volcano, in the Philippines, released 15 million tons of sulfur dioxide into the stratosphere. This tremendous amount took about two years to be depleted through chemical reactions, temporarily cooling the atmosphere by about 0.6 °C on average around the globe. 

Pinatubo’s eruption was used as a source of misinformation by climate denialists who wanted to diminish human interference from global warming — a volcanic eruption only produces temporary effects. As a matter of fact, Pinatubo’s effect was predicted by a climate model, which confirmed the predictions from climate models as reliable sources.

Image credits: Japan Meteorology Agency.

The eruption of Hunga Tonga-Hunga Ha‘apai is not as strong as Pinatubo’s, but the ashes will cool the air a little bit. However, it’s important to keep in mind that this won’t have any significant effect on climate change.

Waves

When the volcano sent ashes flying into the air, it caused a disruption in the atmospheric pressure levels. Just like hitting a drum’s membrane, the explosion pushed the air and changed the air pressure globally.

Researchers monitor these pressure changes through instruments called barometers. But because the planet is very big, the sudden change in air pressure due to the eruption took a while to reach different parts of the planet. For instance, it took 15 hours to reach the University of Hertfordshire Observatory in the UK, which is 16,500 km (around 10,253 mi) away from the volcano and it was registered by their barometer.

The propagation of the wave becomes very clear when we piece together a series of barometer detections. This was registered by the United States’ station on January 15:

The eruption was also a source of waves in the atmosphere, sending concentric ripples traveling the planet’s atmosphere as if it is not such a big deal. A stunning animation of the event was produced by theNational Oceanic and Atmospheric Administration (NOAA)’s GOES-West satellite, displaying the waves traveling the atmosphere just after the eruption.

The initial atmospheric response to the eruption was captured by Mathew Barlow using NOAA’s GOES-West satellite infrared radiance data (band 13). This sequence is based on images taken 10 minutes apart, and colors show the difference in infrared radiance between each time step. Credit: Mathew Barlow/University of Massachusetts Lowell.

So where do these waves go? Well, if you’re a flat-earther, this may upset you. Because the Earth is round, the wave travels to the furthest point, until it reaches a point and becomes a wave source itself that travels all the way around again, gradually losing energy until it disappears. 

There were also some “eyewitnesses” of the process. Registered by the Gemini Observatory at Maunakea in Hawaii, the following video shows a bunch of clouds moving normally, but the thin ripples that appear in the sky were caused by the eruption waves.

Never before could we monitor the atmospheric response to events such as this eruption, this is thanks to the number of cameras we have everywhere and better sensors to register the impacts. We didn’t have a fast way to communicate before, in this case, a few hours after the activity was possible for scientists to share their observations and shock everyone on how interactive the Earth system is. Let’s wait for the next crazy atmospheric phenomenon to leave us in awe.

Researchers send drones to active volcanoes to improve early warning systems

There are about 300 active volcanoes on Earth, and anyone of them erupting could cause wide-scale disruptions. That’s why monitoring them is very important. Now, a group of researchers has created specially-adapted drones that can fly into volcanoes and gather data to warn of any upcoming eruption.

The Manam Volcano. Credit NASA

There are a few ways to forecast when a volcano is going to blow. Scientists can monitor earthquake activity in the area to detect tremors which almost always precede eruptions. With clear skies, satellites are also used to detect and measure the emissions of gases such as sulfur dioxide.

Drones can also help. Volcanologist Emma Liu from University College London and her team focused on the Manam volcano in Papua New Guinea. It’s one of the most active volcanoes in the country, located on an island that off its northeast coast. Manam erupted in 2014 and forced an evacuation of the entire island to the mainland.

“Manam hasn’t been studied in detail but we could see from satellite data that it was producing strong emissions,” said Liu, who led the research team of earth scientists and aerospace engineers. “We [also] wanted to quantify the carbon emission[s] from this very large carbon dioxide emitter.”

Liu and her team traveled to Manam Island and tested two types of long-range drones equipped with gas sensors, cameras, and other devices. The volcano’s slopes are very treacherous, so the drones allowed the researchers to measure volcanic gas emissions more safely and accurately.

The drones flew to over 2,000 meters (6,561 feet) altitude before dipping into Manam’s volcanic plumes some six kilometers (3.7 miles) away from their launching pad. The drones took images of Manam and its two craters, measured the gas composition right above the plumes, and collected four bags of extra gas for rapid analysis.

The images taken by the drones showed that degassing at Manam’s southern crater intensified between October 2018 and May 2019 (the volcano erupted in June). But volcanic emissions aren’t alone a reliable indicator of whether an eruption is likely. That’s why the researchers also looked at the ratio between different gases in the collected samples. Doing so can help detect the ascent of hot magma to the surface through the expulsion of CO2-rich emissions that reportedly precede big eruptions. However, the findings showed that the mixture of gases emitted from Manam was much the same during both field trips. The Manam ranks among the top 10 strongest degassing volcanoes in the world.

“Our novel approach – that is, long-range and high-altitude [drone] operations enabling in situ measurements – is presently the only feasible means by which we can characterize gas chemistry at steep, hazardous, and highly active volcanoes like Manam,” the research team concluded in their paper.

The researchers believe the drones could help local communities monitor nearby volcanoes and forecast future eruptions. At the same time, their measurements could also tell us more about the most inaccessible, highly active volcanoes on the planet and how volcanism in general contributes to the global carbon cycle.

The study was published in the journal Science Advances.

X-Ray Technique Reveals Charred Scrolls From Vesuvius Eruption

Using a new X-Ray technique, archaeologists may be able to read the words from the charred, rolled up scrolls that survived the Vesuvius eruption that wiped out the Roman cities of Pompeii and Herculaneum nearly 2000 years ago. This could open up a new window to the past, revealing much information about the way the Romans lived and is a spectacular technological achievement in itself.

Charred scrolls from Herculaneum. Credit Salvatore Laporta/Associated Press.

“Hundreds of papyrus rolls, buried by the eruption of Mount Vesuvius in 79 AD and belonging to the only library passed on from Antiquity, were discovered 260 years ago at Herculaneum. These carbonized papyri are extremely fragile and are inevitably damaged or destroyed in the process of trying to open them to read their contents. In recent years, new imaging techniques have been developed to read the texts without unwrapping the rolls”, the research writes.

In AD 79, Mount Vesuvius erupted in one of the most catastrophic and infamous eruptions in history, wiping out two thriving Roman cities. The volcano sent fumes up to a height of 33 kilometres (21 mi), ejecting molten rock and pulverized pumice at the rate of 1.5 million tons per second. Pompeii and Herculaneum were completely obliterated. A thousand bodies have been found by archaeologists, but the number of victims is certainly much higher.

Along with the lives and buldings which were claimed, a lot of information was lost as well. Most of the papyri were burned, while others were not burned, but charred beyond recognition. Ironically, even though lava engulfed Pompeii and destroyed pretty much everything from the city, Herculaneum was destroyed by a mix of superhot gases and ash. While this didn’t make much of a difference for the city’s inhabitants, it helped partially preserve some scrolls. When scholars of the 1700s, tried to decipher their secrets, even more damage was caused. But now, a new technique described in the journal Nature gives hope to researchers who have until now been unable to read these delicate scrolls.

The charred remains of the rolled papyrus scroll from Herculaneum. Photograph: E Brun

They want to study the scrolls from a library which includes the works from Greek and Roman authors, such as the lost books of Livy’s history of Rome. Researchers led by Vito Mocella, of the Institute for Microelectronics and Microsystems in Naples, Italy used a laserlike beam of X-rays from the European Synchrotron in Grenoble, France, With this, they were able to pick up slight contrasts between the papyrus fibers and the ancient ink. They tested this technique several times and it worked quite fine, and now the team is working on ways to refine it. While they did figure out some letters and words, it will be quite a while before these works hit the bookshelves.

 

“At least we know there are techniques able to read inside the papyri, finally,” Dr. Mocella said in an interview. His team is considering several ways to refine the power of their technique. “If the technology is perfected, it will be a real leap forward,” said Richard Janko, a classical scholar at the University of Michigan who has translated some of the few scrolls that can be read.

Scientists believe that the author of the scrolls they studied is the philosopher and poet Philodemus. However, there are some limits to what this technique can do. The papyri are so damaged that some of the writing has actually been distorted beyond the point of recognition, and without actually opening them, you can only read a part of the scroll. So far, researchers have been able to  make up the words for “would fall” and “would say” in one parchment, and some individual letters in another one. It may not seem like much, but it’s a great start.

The remains of Pompeii. Image via Passport Files.

“This pioneering research opens up new prospects not only for the many papyri still unopened, but also for others that have not yet been discovered, perhaps including a second library of Latin papyri at a lower, as yet unexcavated level of the Villa,” the study authors wrote.

Journal Reference: Vito Mocella, Emmanuel Brun, Claudio Ferrero & Daniel Delattre. Revealing letters in rolled Herculaneum papyri by X-ray phase-contrast imaging. Nature Communications 6, Article number: 5895 doi:10.1038/ncomms6895

This image shows averaged 2006-2009 ground velocity map of the west Sunda volcanic region from the Japanese Space Agency's ALOS satellite. Positive velocity (red colors) represents movement towards the satellite (e.g. uplift) and negative velocity (blue colors) movement away from the satellite (e.g. subsidence). Locations of volcanoes are marked by black triangles, historically active volcanoes by red triangles. Insets show six inflating volcanoes. (c) Estelle Chaussard, University of Miami

Satellite images hint to volcano eruptions allowing for remote forecasting

In a groundbreaking study, researchers at University of Miami (UM) Rosenstiel School of Marine & Atmospheric Science used satellite imagery to study volcanic eruptions from the past years in Indonesia’s west Sunda arc, a highly active volcanic region. Their findings show that images of inflating magma balloons hint towards impending volcanic eruptions in one in two cases, on average. Considering these deformations can be detected remotely via satellite means that future eruptions can be predicted with much greater accuracy, while also providing an alternative to ground based observations.

 This image shows averaged 2006-2009 ground velocity map of the west Sunda volcanic region from the Japanese Space Agency's ALOS satellite. Positive velocity (red colors) represents movement towards the satellite (e.g. uplift) and negative velocity (blue colors) movement away from the satellite (e.g. subsidence). Locations of volcanoes are marked by black triangles, historically active volcanoes by red triangles. Insets show six inflating volcanoes. (c) Estelle Chaussard, University of Miami

This image shows averaged 2006-2009 ground velocity map of the west Sunda volcanic region from the Japanese Space Agency’s ALOS satellite. Positive velocity (red colors) represents movement towards the satellite (e.g. uplift) and negative velocity (blue colors) movement away from the satellite (e.g. subsidence). Locations of volcanoes are marked by black triangles, historically active volcanoes by red triangles. Insets show six inflating volcanoes. (c) Estelle Chaussard, University of Miami

The team studied satellite image surveys of dozens of Indonesian volcanoes taken between 2006 and 2009, essentially taking their pulse, and saw ground deformation in six volcanoes,  three of which erupted after the observation period, confirming that inflation is a common precursor of volcanic eruptions at west Sunda volcanoes.

“Surveying entire volcanic regions using satellite data is of primary importance to the detection of ground deformation prior to the onset of eruptions. If volcanic inflation is observed, it can help us to predict where the next eruption may occur. Moreover, in regions like Indonesia, where volcanoes are prevalent and pose a threat to millions of people, and where ground-based monitoring is sparse, remote sensing via satellite could become a major forecasting tool,” said Chaussard.

Like tsunamis or earthquakes, volcano eruptions are impossible to predict with 100% accuracy, far from it. What scientists can is only assess the risks of a potential eruption, and armed with a new tool that allows for real-time gathering of critical information they can now  significantly improve their predictions.

Indonesia, however, is a highly active region. The next step is to study other parts of the globe where volcanic activity is frequent. The authors said that they will first study other parts of Indonesia and the Philippines. This time they will use data from the Japanese Space Agency’s ALOS-2 which will be launched next year.

“The notion of detecting deformation prior to a volcanic eruption has been around for a while,” said Amelung, who has been studying active volcanoes for 15 years. “Because this region is so volcanically active, our use of InSAR has been very successful. We now have a tool that can tell us where eruptions are more likely to occur.”

Findings were published in the journal Geophysical Research Letters. 

Volcanic crystals might predict next big eruption

Analysis of crystal formed in the molten rocks of a volcano might predict volcanic eruptions with as much as a year in advance, researchers claim.

Mixing Seismology and Petrology

Different types of seismic recording; volcanic eruptions cause harmonic tremors, different from any other ones. Via USGS

Drawing data from the volcanic activity of Mount Helens from 1980 through 1986, geologists found that iron- and magnesium-rich crystals grow before an eruption, and by far, the most rapid growth of such crystals took place 12 months before an eruption.

Most active volcanoes, before erupting, display specific patterns of seismicity; monitoring these events, as well as, ground deformations, gas emissions and changes in water level are the best thing we have so far in terms of predicting volcanic eruptions. However, while these methods provide good indications, such a technique, if perfected, would dramatically improve the odds of predicting such an event.

“Volcanoes tend to erupt in a similar cycle and have similar trends,” said Kate Saunders, a study author and geologist at the University of Bristol in England, in a telephone interview. “If we can work out their behavior, it allows us to know what to look for. We can better evaluate the monitoring signals.”

Analyzing igneous rocks

Igneous rocks are one of the three major types of rocks (along with sedimentary and metamorphic), formed through the cooling and solidification of magma. When these rocks cool slowly, below the surface, they form visible, specific, crystals. Among the minerals form through this process are orthpyroxenes, silicate minerals comprising of single chains of chemical tetrahedra.

Dr Saunders and colleagues studied zoned crystals of orthpyroxenes, which grow concentrically like tree rings within the magma body. What happens is that these zones have slightly different chemical compositions, reflecting physical and chemical changes in the magmatic chamber where they were formed, thus giving a good indication of volcanic processes and the geological time setting when they occur, much like the rings on a tree.

Forensic mineralogy

Zoned orthopyroxene - not with its real color. The colors show the zones with different chemistries

Researchers used a technique called diffusion chronometry applied to orthopyroxene crystal rims, showing that episodes of magma intrusion correlate temporally with recorded seismicity, providing evidence that some seismic events are related to magma intrusion. Diffusion chronometry works in an almost forensic fashion, and it can must be applied to more volcanoes, in order to verify if this feature is present in all volcanoes, or if this was just a unlikely chance. If it isn’t then researchers have just struck gold.

“Such a correlation between crystal growth and volcanic seismicity has been long anticipated, but to see such clear evidence of this relationship is remarkable.”, explained Dr. Saunders.

Source

Katla volcanic eruption

Icelandic volcano eruption might cause local turmoil

For the past few months, the mighty Katla volcano, close to the Icelandic coast, has been exhibiting intense seismic activity, hinting towards an imminent eruption. With a caldera of 10 kilometers, a long history of causing havoc and pain, Katla has the potential of flooding the Atlantic Ocean with billions of gallons of water left over from the melting of its frozen surface, as well as climate change aftermaths.

“There has been a great deal of seismic activity,” says Ford Cochran, National Geographic‘s expert on Iceland.

Just recently, only in the month of October, about 500 tremors were registered around the caldera of Katla, suggesting magma movement and intense seismic activity. On July 9th a small eruption occurred, foretelling of a greater eruption in the near future,  and since then Icelandic scientists have been closely following Katla’s activity.

Katla volcanic eruption

“The 9 July event seems to mark the beginning of a new period of unrest for Katla, the fourth we know in the last half century,” says Professor Pall Einarsson, who has been studying volcanoes for 40 years and works at the Iceland University Institute of Earth Sciences.

“The possibility that it may include a larger eruption cannot be excluded,” he continues. “Katla is a very active and versatile volcano. It has a long history of large eruptions, some of which have caused considerable damage.”

Some short historical milestones from Katla’s havoc wrecking past: in 1918, the last recorded major Katla eruption was so powerful that entire glaciers were swept towards the ocean. In 1755, the volume of water produced by its eruption was equal to that of all the world’s rivers combined. In 1783 volcanoes in the area, not only Katla, erupted continuously for eight months, the results of which would very much resemble the effects of a nuclear winter – ash, hydrogen fluoride and sulfur dioxide clouded the sky. Back then one in five Icelanders were killed, along with half of the country’s entire livestock.

Some of you might remember another recent eruption from Iceland, though not of Katla, but of Eyjafjallajokull. The name might not ring a bell, but you might recall how air traffic around Europe was halted for days; and Eyjafjallajokull is just like a little cousin compared to Katla. Back in 2010, scientists said a Katla eruption could be ten times stronger than the wrath of Eyjafjallajokull and shoot larger and higher plumes of ash, and also result in a tremendous amount of water seeping through Katla’s opening.

Based on previous patterns, that have Katla massively erupting every 40 to 80 years, it seems that the volcano is due. However, one should not threat too hard upon its consequences. A number of media outlets in the past few days have been over-hyping the effects that Katla’s eruption would pose, the most notable of which is the claim of a global impact. Apart, maybe, from some unpleasant groundings of air traffic in Europe, if the wind conditions are unfavorable, there’s little impact farther from its local surroundings that Katla might be able to generate. Still, Iceland will continue to tread on thin ice for the upcoming months. Pun intended.

 

Nyamuragira eruption Congo

Africa’s most active volcano erupts in Congo [VIDEO]

Spectacular range smoke, ash and lava shot up in to the night sky last night from Africa’s most active volcano, located in  the Democratic Republic of Congo’s Virunga National Park. Congo’s Centre for Research and Natural Sciences claimed in a recent statement that local residents, as well as the precious endangered mountain gorillas living in the park, are not threatened by the eruption.

Nyamuragira, which erupts about every two years, sits northwest of another active volcano in the park. During the past 100 years alone, Nyamuragira volcano has erupted more than 40 times, however during all this time few fatalities have been registered.

“A fountain of lava, smoke and ash came out of a fissure on the side” of a flat area east of the volcano, said CRNS researcher Dieudonne Wafula.

Ash could be carried some distance by the wind, potentially polluting water and burning crops, he warned.

 

AFP

 

Mýrdalsjökull

Iceland braces for even more powerful volcanic eruption

A dramatic overnight increase in seismic activity near the Katla volcano in southern Iceland has brought fears of a dramatic eruption, one that would make last year’s massive air-traffic disruption seem like a walk in the park.

Mýrdalsjökull

Mýrdalsjökull - the glacier in case

“It is definitely showing signs of restlessness,” commented Pall Einarsson, a professor of geophysics at the University of Iceland

Like Eyjafjallajökull, Katla is located on a glacier, but this time, the dimensions vary greatly: we are talking about a caldera of 10 km covered with 200–700 metres of ice. Its last eruption was in 1918, and it was absolutely catastrophic, blocking sunlight across huge areas, destroying plantations and indirectly killing livestock in massive numbers. However, we shouldn’t panic, because even though seismologists explained how increased seismic activity seems to indicate an imminent eruption, there is still a large degree of uncertainty.

Katla in 1918

“However, given the heightened levels of seismicity”, the Icelandig Meteorological Organization added, “the situation might change abruptly. Monitoring teams at IMO are following the ongoing activity closely, and sensor-based networks around the volcano ensure that all seismological, geodetic, and hydrological changes are detected.”

In recent weeks residents of Vik (population 300 approx.), located at the foot of Katla, have participated in emergency evacuation drills in the event of a volcanic eruption and subsequent glacial floods affecting the small coastal town. The thing is, even if an eruption isn’t imminent, it won’t be very long until we have another Icelandic volcano situation on our hands.