Scientists find clues to the mystery of what causes lightning

March 1, 2016 by Lisa Zyga feature
Photograph of a ‘bolt-from-the-blue’ lightning discharge during a nighttime storm over central New Mexico, taken from a distance of about 50 km. The storm occurred on the evening of August 19, 2010. The in-cloud channels of such discharges are obscured from view optically but are being imaged in increasing detail using VHF mapping techniques. Credit: Harald Edens

It's well-known that lightning is an electric current—a quick, powerful burst of charge that flows within a cloud or between a cloud and the ground. But surprisingly, scientists still don't fully understand how the initial spark forms that generates such powerful lightning.

In a new paper published in Nature Communications, researchers from Langmuir Laboratory at the New Mexico Institute of Mining and Technology near Socorro, New Mexico, have reported observations of a rare but extremely powerful type of spark, or discharge, called narrow bipolar events. The scientists found that this powerful type of lightning is caused by a newly recognized type of discharge called fast positive breakdown, and the data suggests that this same discharge initiates most or even all of the typically seen in thunderstorms. These sparks travel at speeds that are fast even for lightning—around 10 to 100 million meters per second—and produce very powerful radiofrequency (RF) radiation as high as a few megawatts, making them the strongest natural sources of RF radiation on Earth.

This discovery is surprising, since previous simulations have shown that lightning breakdown appears to be negative, meaning the spark moves upward in the cloud from a negative to a positive region. In positive breakdown, the spark moves downward from a positive to a negative region.

"It is impossible to simulate thunderstorm conditions in a conventional laboratory," coauthor William Rison at the New Mexico Institute of Mining and Technology told Phys.org. "The sparks in thunderstorms are hundreds of meters to kilometers long, a scale that is orders of magnitude larger than in any laboratory environment. Theorists have been trying to simulate these conditions in computer experiments, and the most plausible results have suggested that the sparks are initiated with relativistic electron avalanches, which is a type of negative breakdown. Our results clearly show that the initiation is with a positive breakdown, not a negative breakdown."

The results could help scientists better understand how a cloud can generate a current that is powerful enough to cause lightning. Currently, the largest electric fields that have been measured inside thunderstorms are several times weaker than what is needed to break down cloudy air and initiate lightning.

In general, lightning occurs when the positive and negative electric charges in a cloud separate in different parts of the cloud. Charge separation sets the stage for lightning to form either between the negative and positive parts of the cloud (intracloud lightning), or downward to the ground (cloud-to-ground lightning), where it often strikes a tree, telephone pole, or other tall object.

Over the past few decades, researchers have gained a better understanding of how the charges become separated in thunderclouds. Data and simulations show that charge separation occurs when small hail-like particles called "graupel" and ice crystals collide with one another in a cloud. The charges are separated as the heavier graupel particles fall, while the lighter ice crystals are carried upward by updrafts in the turbulent thundercloud. This process is somewhat like how rubbing your feet on carpet separates charges in your body, causing you to produce static electricity when you touch a metal doorknob.

Since the 1990s, one of the leading proposals for lightning formation is that the initial spark comes from relativistic electrons that come from either high-energy cosmic rays or a process called relativistic runaway electron avalanche. However, the new results cast doubt on this idea.

"If relativistic electron showers were the initiating events for , then the motion of the breakdown would be initially upward for intracloud flashes between the mid-level negative and upper positive charges," Rison explained. "Using a recently developed broadband interferometer to observe the propagation of electrical breakdown in , we found that the propagation direction of narrow bipolar events is downward rather than upward, showing they are caused by downward-developing positive rather than upward-developing negative breakdown."

Both negative breakdown and positive breakdown can move charges, which can intensify the fields at both ends of the cloud. But the data here shows that all flashes for which the interferometer could determine the motion exhibited an initial breakdown that was fast and positive.

The next step is to investigate how fast positive breakdown develops physically. Fast positive streamers have been observed in sprites, a type of electrical breakdown that occurs in the upper atmosphere where the pressure is several orders of magnitude lower than in thunderclouds. The discharge observed here move at the same fast propagation speeds but at lower altitudes and higher pressures.

"Theorists are now trying to determine how fast positive breakdown works at the higher pressures inside thunderclouds," Rison said.

Explore further: Morning is the time for powerful lightning

More information: William Rison, et al. "Observations of narrow bipolar events reveal how lightning is initiated in thunderstorms." Nature Communications. DOI: 10.1038/ncomms10721

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lawrie1
1.6 / 5 (15) Mar 01, 2016
Scientists find clues to the mystery of what causes lightning
Most people, when they think of electrical storms, they look up and try to find all the answers above their heads. But the earth has a way of generating power from below their feet. With liquid magma flowing beneath the earth's crust, powerful geologic-fluid currents appear to correlate with the rotation and magnetic fields of the earth. With this in mind, electromagnetic storms within this region will produce positive and negative voids around the earth that need to be stabilized. The only way this can be achieved is by the conductivity of the water vapor in the atmosphere. The more water vapor the more conductivity the bigger the storm. In times of geological unrest, it is noted that electrical storms increase worldwide.
cantdrive85
1.8 / 5 (19) Mar 01, 2016
Interesting observations, however the Sun is the primary source for electrical energy in the Solar System. This explains both the geological unrest as well as the increased weather activity.
HannesAlfven
2.3 / 5 (18) Mar 01, 2016
The cloud is simply the optimal path for the discharge. It is not the discharge's source. Up until the observation of lightning to space, this was an excusable mistake. However, scientists have so far refused to ask the question -- with an open mind -- of why clouds would be generating lightning that then travels to space. Obviously, the larger reservoir of charge is space itself, and as cantdrive reasonably points out, the Sun.

That we are even having this conversation says a lot about the worldviews of scientists and the refusal amongst the public to actually think about what is being claimed, in light of surprising observations. It only remains a mystery because the dominant worldview is not pointing scientists to the most straightforward answer.
Whydening Gyre
2.8 / 5 (9) Mar 01, 2016
We look at it opposite to what it is, is the problem. Matter (ground) is the actually the plus (generator of charge),Space is actually the negative (dissipation medium). Our brains can't seem to process it that way, tho...

Guess ya gotta be left-handed...;-)
gculpex
2.4 / 5 (7) Mar 01, 2016
I'm left-handed and it the world is still backwards.....
gculpex
2.1 / 5 (9) Mar 01, 2016
I was thinking with these lightning discharges being in radio frequency, you could find other truly habitable worlds by this effect.
Whydening Gyre
4 / 5 (6) Mar 01, 2016
I'm left-handed and it the world is still backwards.....

Welcome to Opposite World...:-) A cross we must bear to further the enlightenment of the rest of the world..:-)
I was thinking with these lightning discharges being in radio frequency, you could find other truly habitable worlds by this effect.

True, but until we determine the finer characteristics of lightning here on earth, to compare it to, it wouldn't be all that accurate...
Lightning can occur in a variety of environments - not all conducive to the "life as we know it..." paradigm.
d0nkey
2.3 / 5 (6) Mar 01, 2016
wtf
indio007
4.3 / 5 (9) Mar 01, 2016
Hey we can't figure out lightning, the most visible phenomena on earth, from space. However we can figure out gravity waves created 100 billion light years away by objects we can't see!

Damn we're good! Kinda.
Nik_2213
4.6 / 5 (10) Mar 01, 2016
Sadly, Gculpex, Jupiter is a massive source of lightning RF, and it is far from habitable...

Still, kudos for lateral thinking !!
Captain Stumpy
2.7 / 5 (7) Mar 01, 2016
I'm left-handed and it the world is still backwards.....

Welcome to Opposite World...

i'm ambidextrous and dyslexic...
just imagine how things are for ME!
Hyperfuzzy
1 / 5 (6) Mar 01, 2016
An object that is electrically "floating" may have any desired static field created from radiation from the sun, the existing field of gravity (electrical, not another force of nature) and the existence of a field upon any other object either positive or negative created by pollution. The flow is the least resistive path. The path, + to - or - to + depends upon the "bundle of charges" least number per bundle to most number per bundle. Smaller mass to larger mass. So the source is the planet. Why is this so poorly understood?
Protoplasmix
4.8 / 5 (8) Mar 01, 2016
Jupiter is a massive source of lightning RF, and it is far from habitable...
Good point about the lightning. But Jupiter's not far from Europa (670,900 km), and if habitable is where you hang your helmet and spacesuit... :)
torbjorn_b_g_larsson
4.2 / 5 (10) Mar 01, 2016
Interesting! Lightning modeling was a must in the physics courses at my university.

Sounds like protons or rather OH3+ are the carriers.

"The breakdown is found to have a wide range of strengths and is the initiating event of numerous lightning discharges. It appears to be purely dielectric in nature and to consist of a system of positive streamers in a locally intense electric field region."

[ http://www.nature...721.html ]

But also here: "Currently, the largest electric fields that have been measured inside thunderstorms are several times weaker than what is needed to break down cloudy air and initiate lightning."

That may suggest the graupel/ice 'Van der Graff' generator suffers from stochastic breakdown in between the streams of particles, weather permitting.
torbjorn_b_g_larsson
4.3 / 5 (11) Mar 01, 2016
Interesting side thread on habitability (yes, it has been looked at but is not a habitabibility signature alone, c.f. Jupiter), but of course everyone expected the Electric Inquisition.

The observations tested yet again that the charge mechanism is inherent to the clouds, as if it wasn't thunderously obvious.

Electric Monk: "EVERYBODY expects the Electric Inquisition! Our chief weapon is routine...routine and ignorance...ignorance and stupidity.... Our two weapons are ignorance and stupidity...and ruthless buffoonery.... Our *three* weapons are ignorance, surprise, and ruthless buffoonery...and an almost fanatical devotion to the Electric Universe Dope.... Our *four*...no... *Amongst* our weapons.... Amongst our weaponry...are such elements as ignorance, stupidity.... I'll come in again."
Whydening Gyre
5 / 5 (5) Mar 01, 2016
Electric Monk: "EVERYBODY expects the Electric Inquisition! Our chief weapon is routine...routine and ignorance...ignorance and stupidity.... Our two weapons are ignorance and stupidity...and ruthless buffoonery.... Our *three* weapons are ignorance, surprise, and ruthless buffoonery...and an almost fanatical devotion to the Electric Universe Dope.... Our *four*...no... *Amongst* our weapons.... Amongst our weaponry...are such elements as ignorance, stupidity.... I'll come in again."

Hunh... I must have missed that one....
Dug
1.3 / 5 (7) Mar 01, 2016
Sad. You might all might want to look at Lord Kelvin's water drop generator. Kelvin understood and demonstrated (not theorized) how electrical charges form in clouds and create... in 1887. I'm not sure this work and article are any more illuminating regarding "the mystery (so called) of what causes lighting." - which was the title of this theoretical article.

https://en.wikipe..._dropper
bluehigh
5 / 5 (4) Mar 01, 2016
For those that may have missed the connection with mangled mess that Torbjorn presented, here's the original ...

"No one expects the Spanish Inquisition! Our chief weapon is surprise, fear and surprise; two chief weapons, fear, surprise, and ruthless efficiency! Er, among our chief weapons are: fear, surprise, ruthless efficiency, and near fanatical devotion to the Pope! Um, I'll come in again..."

- Graham Chapman
Captain Stumpy
3.9 / 5 (7) Mar 01, 2016
Hunh... I must have missed that one....
@Whyde
see: The Spanish Inquisition

https://www.youtu...jmoSMJ-o

.

@Blue
sorry for the repeat
your post didn't show up until after i posted, even though it was posted 22 min before me

.

just a thought
you know, considering the similarities between TL's "electric monk" argument (AKA Spanish Inquisition - Python) and the electric universe... perhaps we should only link the youtube video whenever they post?
yep
1.4 / 5 (10) Mar 02, 2016
Ignorance and buffoonery are rampant in science zealots who are unwilling to realize they do not know everything.
Just think layers of an onion this might help.
http://nova.stanf...97sciam/

So Torb enlighten us to where the graupel/ice is in the outer atmosphere?
jonesdave
4.3 / 5 (12) Mar 02, 2016
Soon as I saw the title of this article, I knew the electric cretins would be out in force!
AGreatWhopper
2.6 / 5 (10) Mar 02, 2016
Yeah. I'm not going to comment anymore. Time to hit the streets and deal with the problem. A cattle prod should be a fine start...
chileastro
2.8 / 5 (11) Mar 02, 2016
Sadly, Gculpex, Jupiter is a massive source of lightning RF, and it is far from habitable...

Still, kudos for lateral thinking !!


Mental cases aren't thinking laterally, they're thinking dysfunctionally. Or maybe I should tell the schizophrenics I work with that they're not sick, they're just thinking outside the box.


Dug

1 /5 (2) 8 hours ago
Sad.


Yes, you are.
jim_xanara
3 / 5 (10) Mar 02, 2016
cantdrive85 1.9 / 5 (15) 20 hours ago
Interesting observations, however the Sun is the primary source for electrical energy in the Solar System. This explains both the geological unrest as well as the increased weather activity.


Well, I hope you're doing some experiments. That could be productive. You might electrocute yourself to death. Hope your handle is accurate. It would be nice to think of people who come to a serious science site to troll electric sun SHITE will end in a twisted heap of metal.

These zealots must not even believe their own press. "I'm so great, so much better than real scientists, and I deserve such recognition...that I'm using an alias". Right. What a pitiful waste of resources.
cantdrive85
1 / 5 (7) Mar 02, 2016
cantdrive85 1.9 / 5 (15) 20 hours ago
Interesting observations, however the Sun is the primary source for electrical energy in the Solar System. This explains both the geological unrest as well as the increased weather activity.


Well, I hope you're doing some experiments. That could be productive. You might electrocute yourself to death. Hope your handle is accurate. It would be nice to think of people who come to a serious science site to troll electric sun SHITE will end in a twisted heap of metal.

These zealots must not even believe their own press. "I'm so great, so much better than real scientists, and I deserve such recognition...that I'm using an alias". Right. What a pitiful waste of resources.

What a lovely human being you are, an inquisitor of scientific dogma in the flesh. I'd like to return the heartfelt greetings and wish you and all your family to burn in hell you useless POS!
HannesAlfven
2.1 / 5 (7) Mar 02, 2016
Some articles which might help the skeptics on lightning as simply an aspect of a circuit ...

The Van Allen radiation belts blink in coordination with lightning, THOUSANDS of miles away
https://www.nasa....Bj2QrJdA

I'm not sure why people would get so worked up over this that they would feel the need to wish another to electrocute themselves. Electrical circuits should have stopped being controversial back in the day of Maxwell, and we use electricity over plasmas to do all sorts of things in consumer electronics. We've known since we sent the first rockets into space that, simply by observation, it appears that space is quite conductive. And in fact, conductivity is simply a statement about charge mobility.
katesisco
2.3 / 5 (4) Mar 02, 2016
Not understanding. Is the Earth gaining mass? Per W Thornhill theory in EU? And then becoming an anode instead of a cathode?
torbjorn_b_g_larsson
4.4 / 5 (7) Mar 02, 2016
" perhaps we should only link the youtube video whenever they post?"

That was what I was thinking.

@yep: If you are asking for mechanisms for sprites et cetera, it is in the article.
@cantread: Magic (curse) peddling.
@HA: Don't even try, the discussed work rejects that. As I have already noted...

Honestly, does cranks ever read the science, or the comments?

Guess it is time for this again:

https://www.youtu...jmoSMJ-o
torbjorn_b_g_larsson
4.5 / 5 (8) Mar 02, 2016
Oops, more specifically on HA's "that", rejects that the charge separation mechanism happens outside the clouds.

https://www.youtu...jmoSMJ-o
Hyperfuzzy
2.3 / 5 (3) Mar 02, 2016
OK, everything is made out of charged particles, nothing else. Just the protons and electrons. I prefer +&- particles. The potential of the earth is both + & -. The field of these particles always exist and are additive.The cumulative field is greatest near the earth. There is a potential difference from clouds and the earth and maybe whatever particles contained and other locations, conductivity defining the path. If any particles exist between two potentials and the potential is high enough the air will break and we get lightening. There is nothing magic going on. It's simply an equalization among a surface in the field, nothing else. Or to put it another way, a correction! The varying fields always exist and are still there. OK, now whose gonna try and measure the variation? Use a very High input diff amp a very good probes separated by altitude. Be careful and fast. You will have a tough time catching the delta, fast changes, faster than lightening, juz say'n
bschott
1.8 / 5 (5) Mar 02, 2016
Hey we can't figure out lightning, the most visible phenomena on earth, from space. However we can figure out gravity waves created 100 billion light years away by objects we can't see!

Damn we're good! Kinda.


Awesome way to put things into perspective.
TimLong2001
1 / 5 (1) Mar 02, 2016
The spatial charge distribution of water molecules, and their charge alignment in thunderclouds, might be a contributing factor.
jonesdave
4.1 / 5 (9) Mar 03, 2016
Not understanding. Is the Earth gaining mass? Per W Thornhill theory in EU? And then becoming an anode instead of a cathode?


Thornhill is a clueless eejit. He thinks comets are electric, Earth used to orbit Saturn and Valles Marineris was created by a lightning bolt. Among other weird sh*t. Not to be taken seriously.
cantdrive85
1.7 / 5 (6) Mar 03, 2016
Not understanding. Is the Earth gaining mass? Per W Thornhill theory in EU? And then becoming an anode instead of a cathode?


Thornhill is a clueless eejit. He thinks comets are electric, Earth used to orbit Saturn and Valles Marineris was created by a lightning bolt. Among other weird sh*t. Not to be taken seriously.

This statement from the eejit that is clueless about electrochemistry and plasmas...
HeloMenelo
2.3 / 5 (3) Mar 05, 2016
cantdrive still can't drive, say... can you count your toes yet... let mommy count them for ya ... ;)
HannesAlfven
2.7 / 5 (7) Mar 06, 2016
Spin machine is on full blast to make sure that we keep lightning complicated and mysterious. Let's review how "complicated" this is ...

(1) Lightning that sources from clouds lacks a "seed" field that is sufficiently strong to get started.

(2) Lightning emissions are surprisingly powerful.

(3) Over just the past couple of decades, long after lightning theory was formed, it has become apparent that there is also lightning which connects to the ionosphere, violating the debye length there by a factor of 50-million-to-1 (50 km vs 1 mm expected).

(4) We also see changes in the Van Allen radiation belts in sync with terrestrial lightning strikes.

(5) Increased solar wind activity increases the total number of lightning strikes.

Okay, who can make this complicated for us? We must stop people from having simple thoughts.

Anybody?
Hyperfuzzy
3 / 5 (2) Mar 07, 2016
Spin machine is on full blast to make sure that we keep lightning complicated and mysterious. Let's review how "complicated" this is ...

(1) Lightning that sources from clouds lacks a "seed" field that is sufficiently strong to get started.

(2) Lightning emissions are surprisingly powerful.

(3) Over just the past couple of decades, long after lightning theory was formed, it has become apparent that there is also lightning which connects to the ionosphere, violating the debye length there by a factor of 50-million-to-1 (50 km vs 1 mm expected).

(4) We also see changes in the Van Allen radiation belts in sync with terrestrial lightning strikes.

(5) Increased solar wind activity increases the total number of lightning strikes.

Okay, who can make this complicated for us? We must stop people from having simple thoughts.

Anybody?

Don't forget gravity waves and a breakdown in Gluon activity with remnants from the big bang encouraged by dark matter!
Lex Talonis
not rated yet Mar 08, 2016
Lightning - that is just elementary equation of series parallel capacitance..... HUGE 3D volumes and squillions of of billions of charges - Duh....

chapprg1
not rated yet Mar 31, 2016
Did I not read that cosmic rays are primarily protons. This would constitute a current flow from space which accumulates a charge in the upper atmosphere until it collects high in the thunderheads to the point where it discharges. It would also account for the sprite phenomena of currents in the extremely rare stratosphere discharging to the clouds as they loose their positive charge to ground. Lets get some measurement and theory about where these accumulate and at what quantity. According to theory they do not penetrate easily to low altitudes because the air is an insulator.
arationofreason

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