Experimenting with 13,000-year-old ash, scientists learn why volcanic lightning forms

On this Earth, there are few phenomena as wonderfully beautiful and extremely dangerous as volcanic lightning: a huge column of smoke erupts from the mouth of a large mountain, volcanic dust particles collide to create static electricity will create the scene of a fantasy story with dragons and magic.

We are interested in volcanic lightning , science looks at this natural phenomenon with a curious eye: how does volcanic lightning form? Although they know the role of dust particles, the truth is clearly not so simple. That’s why for so long, scientists have been trying to create volcanic lightning in the laboratory.

Experimenting with 13,000-year-old ash, scientists learn why volcanic lightning forms
Volcanic lightning – a wonderfully beautiful natural phenomenon.

The latest success is perhaps the attempt to produce results that are closest to reality. In the study, published in Geophysical Research Letters, the scientists wrote that they were able to change the properties of volcanic smog , changing the temperature of the smoke as well as the density of the smog can determine the success and failure of volcanic lightning.

Experimenting with 13,000-year-old ash, scientists learn why volcanic lightning forms
It seems that dry smog is the key to creating the natural wonder of mankind.

This experiment isn’t just about satisfying curiosity and figuring out how to make your own volcanic lightning for fun: volcanic lightning is how we can detect volcanic eruptions from a distance. The more we know about how a volcanic lightning occurs, the easier it is to determine exactly what type of eruption is taking place, in order to reduce the workload on air traffic control and save the lives of communities. who live at the end of the wind.

Sönke Stern, a researcher of volcanic lightning at Ludwig Maximilian University and lead author of the new study, is well aware of the contributions he has made to humanity in general and science in particular. However, he also told Gizmodo like this: ” Honestly, sitting down and blowing up those rocks every day makes me very happy .”

Similar to lightning in thunderclouds, volcanic lightning also possesses one key element: the need to clearly separate positive and negative charges . When physics can’t keep the two sides of the charge apart, lightning will appear, tearing apart the insulating air film.

Experimenting with 13,000-year-old ash, scientists learn why volcanic lightning forms
Volcanic lightning needs to clearly separate negative and positive charges.

The composition of the smoke column of volcanic lightning is also different from that of ordinary clouds: the main factors that make up the smoke are volcanic ash. “ We’re pretty sure that the friction particles created the electrification, ” says Alexa Van Eaton, a volcanologist from the US Geological Survey’s Cascades Volcano Observatory.

The fact that dust particles collide with each other is an example of friction generating electric charge – also known as … electric friction. Researchers know this when doing fieldwork, because then they can see firsthand the phenomenon they are trying to explain. Researcher Cassandra Smith, also at the Cascades Volcano Observatory, told Gizmodo: “ The fieldwork is very important.

Sadly, ” you can’t predict what the volcano will do ,” Ms. Smith said. It’s too hard to track volcanic lightning in real life , because you know, around lightning storms is extremely hot smoke spewing from one of the most difficult environments on Earth. Fortunately, we have a laboratory environment to study.

Experimenting with 13,000-year-old ash, scientists learn why volcanic lightning forms
It’s too difficult to track volcanic lightning in real life.

Ludwig Maximilian University is one of the few places with a laboratory that can reproduce volcanic eruptions in the most realistic and accurate way. Besides, they can also create lightning in the laboratory. At the lab, the most frequent name is Corrado Cimarelli, volcanologist and co-author of the new study.

In their latest test, they used an experiment called the bombshell: a chamber containing compressed argon gas and ash that explodes when a certain pressure limit is reached, firing the gas into a steel chamber. The smoke and dust will erupt at an extremely high speed, and it is from there that volcanic lightning is formed. Thanks to the heat from the kiln, the ash can reach more than 300 degrees Celsius.

The test ash wasn’t fan soot or anything trivial, it was the remains of a 13,000-year-old eruption of the (now dormant) Laacher See volcano. The team was fortunate to receive 300 kg of ash from a quarry company operating near the volcanic area.

The team of scientists discovered that: at room temperature, lightning bolts will be larger but appear less; The higher the temperature, the weaker the lightning intensity will appear, the denser the appearance. Although they know that temperature plays a big role, they don’t know how lightning forms and what else plays a role in making volcanic lightning.

The effect of water is most obvious: as long as the volcanic ash is slightly moistened, the electrostatic potential of the ash complex is reduced several times. When the ash is so moist that it’s pasty, no lightning will appear. They put their hands on their foreheads, wondering why.

After several tests, the team discovered that the steam ejected at a much faster rate than argon, creating a larger explosion, increasing the size of the ejected ash cloud, causing the ash to scatter. So the ash does not have a chance to rub against each other to create static electricity. Conversely, the drier the ash, the more volcanic lightning will be.

Experimenting with 13,000-year-old ash, scientists learn why volcanic lightning forms
As long as the volcanic ash is slightly moistened, the electrostatic potential of the ash complex is reduced several times.

In real life, there is still too little data from surveys showing that moist ash produces less lightning. It’s not clear why, but here’s the truth: if you add water to hot magma, the explosion will become much more powerful. It is not clear what the difference is between “water + magma” and “water + ash” , but it is likely that when the magma is moist, the ash will be less likely to collide with each other and generate electricity.

On the other hand, dry ash is much easier to generate electricity . According to researcher Stern, the ash itself is an ineffective insulator, so the dust particles separate, selfishly hold their charge, and can only discharge on impact. and create lightning.

What comes from the experiment helps science much better understand how volcanic lightning forms. But researcher Smith also stressed that it is difficult to isolate each of the factors that influence volcanic lightning, even under tightly controlled laboratory conditions. That is, it is not possible (or at least not yet) to specify which factors cause volcanic lightning.

And the above experiment only studied the phenomenon occurring in the lower part of the smoke column . When volcanic ash flies high enough, it is the ice particles that cause the volcanic lightning. “ The upper region is an entirely new, unexplored realm of volcanic ash static electricity, ” says lightning researcher Van Eaton.

Volcano observation satellites may be blocked by clouds. Other than relying on volcanic lightning to analyze, we have no other way to determine the properties of the ash mass emitted by a volcanic eruption. The smog emitted by a “waking up” volcano can bring down airplanes, destroy homes, pollute water sources and directly affect human health, so knowing the nature of ash will help me a lot.

The more we know how ash is (by observing and analyzing volcanic lightning created from the giant ash cloud), the better we understand what that deadly smoke contains.

But it’s also difficult to appreciate the significance of the study, and there’s no doubt about the group’s motivations. Indeed, volcanic lightning is a very “cool” phenomenon, if given the opportunity (with a sealed laboratory and 300 kg of 13,000 year old ash), we would also sit all day to create volcanic lightning just for fun.

Fortunately, scientists, with the ability to study closely what happens in a cloud of dust, have these experimental tools at hand. The greater the power, the greater the responsibility, my uncle named B. often said this.