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Detailed footage reveals what triggers lightning
- curmudgeon22 5y agoPretty neat overall. I thought this was an interesting random fact: > The key role of ice crystals dovetails with recent findings that lightning activity dropped by more than 10% during the first three months of the COVID-19 pandemic. Researchers attribute this drop to lockdowns, which led to fewer pollutants in the air, and thus fewer nucleation sites for ice crystals.
- redis_mlc 5y ago
- criticaltinker 5y agoThe clickbait headline belies the content of the article: researchers still don’t know exactly what triggers lightning. Personally I find the leading hypothesis a bit absurd or at least unbelievable. The idea that colliding ice crystals shed electrons and form ionized air in masses great enough to trigger the most energetic phenomenon on the plant seems … like a Newtonian hammer looking for a nail. It’s well known that the sun emits a powerful electric field which causes the “northern lights” to appear at the poles of the planet. And it’s well known that solar activity is correlated with large scale weather patterns and atmospheric thermodynamics. How is the Sun not a viable explanation for the origin of lightning? Cosmic rays initiating an electron cascade is interesting, but I would expect the sun to play a bigger role than that.
- keyle 5y agoThey did say that it was the leading hypothesis that this puts aside.
- caf 5y agoThe auroras aren't caused by the Sun's electric field impinging on the Earth, they're caused by actual charged particles from the solar wind entering the atmosphere and ionising air molecules.
- Aerroon 5y agoLightning isn't that energetic. A 16 MW wind turbine can capture the energy of a lightning bolt from thin air in about 1 minute. The average lightning bolt that strikes the ground contains about 1 billion joules of energy. That's 1 GJ of energy. The Siemens Gamesa’s SG 14-222 DD wind turbine has a capacity of 14 MW. In 71 seconds that wind turbine would capture the energy of a lightning bolt. There is an enormous amount of energy in the air moving around us. I can very well believe how that movement can charge up lighting.
- hypertele-Xii 5y agoWith an average duration of 0.2 seconds, a bolt of lightning therefore has like 355 times the energy of your wind turbine for the same length of time. Sounds fairly energetic to me.
- throwaway2344lh 5y ago> Sounds fairly energetic to me. Sounds fairly powerful to me.
- bawolff 5y agoIf you assume that it takes a while to build up for a sudden discharge, that doesn't sound like that much to me.
- Terr_ 5y agoAlso we don't know how much atmosphere-volume per second is needed for 1 "normal" lightning strike. (Assuming some sort of volume-based cause.) In contrast, the amount of air passing through the blades of a turbine per second is probably much easier to calculate, and I'd wager less.
- TeeMassive 5y agoYou're mixing energy and power.
- lrem 5y ago
- lrem 5y agoHow does sun send its electric energy to a 70m wide region of the cloud? Aurora borealis is 80-1000km across.
- Mikejames 5y agois this still the case when you get lightning triggered from large amounts of smoke in wild fires? i’ve seen footage of fires in australia where the smoke becomes so big it starts to cause it’s own lightning
- jcims 5y agoOr volcano ash: https://volcanoes.usgs.gov/volcanic_ash/lightning.html https://volcanoes.usgs.gov/volcanic_ash/lightning.html
- brendoelfrendo 5y agoThat seems to track; pyrocumulonimbus clouds happen when smoke mixes with cooler air high up. The soot and smoke could provide the nucleation sites the article talks about that promote ice crystal growth.
- jcims 5y agoI just love how perfectly this squeaks more science out of an existing investment with seemingly no ill effect on its intended use. I imagine there will be lightning studies out of this observatory for decades.
- boeingUH60 5y agoMakes me remember when the CIA considered using lightning as a killing weapon...maybe they're watching closely now https://www.popularmechanics.com/military/weapons/a34100542/cia-considered-using-lightning-as-weapon-declassified-documents/ https://www.popularmechanics.com/military/weapons/a34100542/...
- mikewarot 5y agoGiven a sufficient budget and time, I think this could be made to work, on a clear day. How? Nitrogen lasers in low earth orbit target the upper end of the atmosphere in a volume over the target as the satellite approaches the target then at azimuth fire a larger pulse directly at the target, ionizing a channel all the way from the top of exosphere to ground, grounding the collected charge from the now conductive volume, to the target.
- 988747 5y agoI guess that would be pretty useless, because you would have to catch your target in open field, during the thunderstorm, which is highly unlikely, since most people hide from it. Targeting a car could be solution, but even then, if the victim has their seat belts on they would probably survive the crash.
- fjfaase 5y agoLast summer, we walk half way around the LOFAR superterp and along some other LOFAR stations in the area. It is in a rather quiet nature reserve. I recognized the roads we walked in the back ground of the animation, which is from a point in the sky looking down towards earth.