NOT what you think! Contrails

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Why would the crew of an airliner change their route to avoid the creation of contrails, behind their jet? How would they even do this, and what do Google and AI have to do with it all?
In this video, I will explain all this and also show you how, in the future, contrails could become rarer. Or they could become even more commonplace. Confused?
Stay tuned!
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Below you will find the links to videos and sources used in this episode.
• Those long, thin cloud...
• Exploring the contrail...
• The future of flight: ...
• Airlines Using AI to R...
• Contrails
• Climatology of Contrails
• Aircraft wing condensa...
• The Shuttle's Last Fli...
• Emirates 777 wake vort...
• Airplane engine intake...
• F-18 Super Hornet San ...
• Spokane City Councilma...
• Joe Rogan on Chemtrails
• Concrete examples of f...
• Menzies Aviation - Fue...
• In the Making: First A...
• Can flying go green?
• American Airlines new ...
• How Jet Fuel Is Made F...
• Fueling the Future wit...
• NASA and DLR flight te...
• 2022 ecoDemonstrator
• GE90 - Accessory Gearb...
• Can sustainable aviati...
• Why Hydrogen-Powered P...
• #ZEROe Fuel Cell engin...
• Airbus #ZEROe Series t...
• General Electric | Com...
• Early morning Contrail...
• UPS MD-11 Landing Port...

[@MentourNow]

Use the link www.magictravel.ai/?r=mentournow to try booking your next trip with Magic for free!

[@hans-uelijohner8943]

Bloody hell, your version works well??

[@Tod_oMal]

Thanks for the 20+ minutes Google ad.

[@Noxumbra7772]

If the AI tool is free, YOU are the product being sold. I don't know I trust this.

[@notfound3358]

You know damn well they're spraying some stuff in the sky for whatever reason! I understand that you need to keep your job and your channel, but you shouldn't deceive your audience like this😠

[@Tod_oMal]

@@notfound3358 Well, don't expect him to tell the truth. He is part of the propaganda.

[@pjcarter8230]

Interesting. I recall being told by some older pilots and flight engineers who flew in WW2 that they often changed altitude to avoid leaving contrails, as a contrail was an arrow pointing to the aircraft and making it a target for flak or enemy fighters. They altered altitude on the fly as it were either observing the contrail by looking back or being alerted to it by other friendly aircraft.

[@fToo]

A few years ago Sir Brian Burridge mentioned that when he was an RAF pilot in the 1970s and 1980s they regularly checked for contrails (I think he said they used a mirror in the cockpit) and changed altitude to stop creating them

[@davidcarter4247]

That is correct but there were limits. An altitude where contrails did not form might have been too low for a mission. Besides, radar meant formations could be detected long before they could be seen.

[@jimrobin]

I watched a film (movie if you prefer) about a general aviation pilot taking his plane across the Pacific to Australia I think it was. He got into difficulty and radioed for assistance. The call was answered by a commercial pilot who went out of his way to assist the lost pilot. He climbed to a height that would leave a contrail but conditions at that time were unfortunately not really conducive to contrails and the commercial pilot became frustrated by this. It all ended happily and I understand both pilots became close friends.

[@davidcarter4247]

@@derektaylor2941 At the start of WW2 Japan was not under threat from high altitude bombers. By the time they arrived in 1944, Japan had radar. The radar Germany used was very good. The FuMG 65 Würzburg-Riese radar was introduced by 1942 and was accurate enough for gun-laying and could detect aircraft 70km away.

[@SHB373]

Indeed. Capt Gordon Vette & crew aboard an Air NZ DC10 en.wikipedia.org/wiki/Cessna_188_Pacific_rescue@@jimrobin

[@nicolaeapostolescu7332]

As a chemical engineer, this episode was very close to my field than the aeronautical field. Very well documented and very well presented. Congratulations!

[@MaisistkeinGemuese]

I found the Chemtrail Engineer!!! /S

[@kiwitotv1461]

please don`t say chemtrails are a hoax

[@Joseph-ft4gh]

I, as another commenter mentioned, always thought contrails were just formed when the very hot engine exhaust hit the quite cold air at high altitudes. You really did a great job explaining what contrails are and how they are formed. I certainly don’t have the answer to whether all the development and costs associated with reducing or eliminating contrails is worth the effort. However, look at all the advances in our world that have been made, not only to the aviation industry, by thinking outside the box. Thank you for all your great videos - I really enjoy watching, and some I watch more than once!

[@hariszark7396]

There are contrains, a few meters behind the airplanes for a few seconds. And there are the CHEMTRAILS that are a few kilometres behind the airplanes that stay there for hours spreading over time in the sky. Do you understand the difference? Do you understand that contrails front the difference of temperature can't stay there for so long and spray over time? Can you understand that this is NOT a physical phenomenon?

[@johnstreet797]

it's like cremation, that's thinking outside the box...

[@kenbrown2808]

the dark side of this is that if a computer can identify a contrail in a satellite photo, a computer can identify which parts of a Captcha photo contain a traffic light.

[@texasranger24]

since 10 years computers can solve captchas with 99.9% accuracy while humans hover around 50%. recaptchas don't track which panel you click, but the mouse acceleration and movement accuracy of how you get there...

[@kenbrown2808]

@texasranger24 way to spoil a good joke with actual facts.

[@iannicolson]

@@texasranger24 Yeah I've read that captcha/recaptcha is actually used to train software for object recognition and OCR. The idea is that the computers don't actually know yet which of the panels contain, say, traffic lights. It learns through millions of user responses.

[@MatthieuBrucher]

Originally, yes. Had not been the case for a long time now.

[@Kalvinjj]

The thing is that they've made you think they're testing you, but you're the one teaching the machine all along...

[@PRH123]

Jumpseating once we flew right through someone else's contrail, I was really surprised by the appearance and didn't initially understand what it was, as it looked like a trail of thick greasy black smoke with what looked like flames inside it... the crew kind of laughed and told me sometimes when the sunlight hits them just right they can look like that at altitude....

[@joshiasbaja3934]

I have noticed that too! From the passenger window

[@buckjones4901]

I noticed they appear like the day before it rains often, and I see them in grid like patterns that would make no sense for air travel, there is more here going on than contrails which dissipate fairly rapidly not create cloud cover.

[@rager1969]

After 9/11, there were no commercial flights over the US for a few days and scientists used this rare opportunity to study the lack of contrails.

[@fakename8856]

This is not true. Bullsh!t líes.

[@EonityLuna]

If I remember correctly it was from that rare opportunity that they discovered that contrails have a significant dimming effect on the weather; you can look up Global Dimming about that. They had an opportunity again during the Covid pandemic to study that on a global scale when demand in air travel crashed, apparently.

[@alexanderSydneyOz]

Lack of flights cannot be used to study the lack of contrails specifically, as it also means a lack of CO2 laden engine exhaust. Which, I would think, has a FAR greater impact on atmospheric effects than occasional contrails.

[@fallentreewoodcrafts]

I found this very interesting and a far more complete and balanced perspective than found in most media. As a resident of Nebraska, i.e., "fly over country," I see a lot of contrails. Some days they persist for many hours; other days they dissipate quickly. It is good to have a better understanding of what they are. Thank you.

[@allenschermerhorn941]

as is the way with fog at low elevations, sometimes it takes hours to burn off via the sun's rays, other times it disappears in what feels like minutes. it's all dependent upon temperature, humidity, winds, dew point, etc.

[@gigachad4751]

A interessting video. As someone who lives on a very rural land site with nearly 90% of forest surrounding us its very special to hear about the impact water vapour may have on air quality. We don't have Smog or any big pollution here so I can't compare to bigger citys but I can see the impact that less radiated heat during night has on overall air quality. About 4 weeks ago i've red a book about this topic (Flygreen for german speaking ppl) about this and was surprised to find such little data on it so im very interessted how stuff like water vapor impact will develop during more years. Glad to see now that airlines are already using software to dodge such "contrails enhancing enviroments". Looking forward to more vids on topics like that and maybe some more E-flying in the future!

[@Voltikz95]

A good side note about vapour cones is that they aren't a sonic boom. There are common misconceptions when people see these and scream, "LOOK! IT JUST BROKE THE SOUND BARRIER!"

[@paskintexas]

He said transonic so although the plane isn’t faster than sound, some airflow around it is - Transonic flow is air flowing around an object at a speed that generates regions of both subsonic and supersonic airflow around that object.

[@InsaneBimmer]

Are people really that dumb? Nevermind I remember Covid.

[@elenasimon1270]

I miss those booms.

[@ashnur]

yeah, transsonic speed is not required, but don't expect scientific accuracy from a youtuber

[@Voltikz95]

@paskintexas which is why I didn't say he was wrong in calling it transonic. Just pointing out the huge misconception that the vapour cone is the aircraft literally breaking the sound barrier. Vapour cones are not sonic booms, and are not indicative of the aircraft breaking the sound barrier. The speed depends on the critical mach number. The phenomena is seen closer to the speed of sound, somewhere around mach 0.8-1.2, but is not a sign of the sound barrier being broken. Given the right circumstances, vapour cones can form at much lower or much higher speeds.

[@jochemvdouw4652]

Super interesting! Also when flying in the night worsens the effect of contrails trapping heat to escape as it is colder and the contrails thus have a longer lifetime. Thus maybe implementing the SAF's in a larger extend on night flights might have the best effect!

[@doncoxe644]

I'd heard that contrails were a problem but had no detail on the subject. You've provided it! Thank you for a most informative explanation of the issue.

[@SteveSmith-en7ud]

Thank you for an excellent, calm, objective presentation of the science of this vital topic.

[@hreader]

I've always suspected that contrails must be a problem simply because of the large area of sky covered in cloud when conditions are favourable. Sometimes the area of cover comes near to rivalling natural cirrus. So many thanks to Petter for explaining the real reasons for concern.

[@leosmith848]

Global temperatures have tracked the rise of air traffic far more closely than the increase in CO2. Air traffic is now stable, as are global temperatures.

[@liam3284]

September 2023 was record hot at +1.72

[@leosmith848]

@@liam3284 And how do you know that? Who told you? Who pays their salary,? How do they measure it? Why do you trust them?

[@miscbits6399]

Water vapour in the stratosphere is particularly bad as a greenhouse gas, vs at lower altitudes. As Petter has mentioned, the increased albedo of stratospheric clouds has a slight cooling effect during the day. The insulating effect applies regardless of the formation of clouds (it's slightly increased when clouds are visible) and as such, flying to reduce daytime contrails is largely pointless IMHO[*] and greater emphasis needs to be placed on reducing soot production Putting it all in context though: Last year's Tonga eruption increased the total mass of water vapour at those altitudes by 12% IN ONE HIT whilst aviation only raises it by 1-2% over normal levels [*] Disclosure, I was involved in a project to quantify planetary albedo over time by analysing decades of satellite imagery dating back as far as we could lay our hands on(**). Nighttime clouds warm things up by preventing more long-wavelength Infrared being emitted to space, daytime clouds reflect more sunlight carrying higher energy short wavelength infrared (heat) reaching the ground than the longer wavelength infrared heat they trap (**) Cloud cover is only part of that project. Bare ground vs water vs vegetation vs cities all have different reflectivity and needed to be quantified in order to work out net planetary sunlight absorbtion and assess the _actual_ heating effects of atmospheric gasses (short answer, the effects are self-feeding and the more heating there is, the more water vapour is getting into the atmosphere but to a large extent water vapour heating becomes self limiting due to cloud formation and greater reflectivity, vs CO2 and CH4 heating effects)

[@losertocloser]

​@@leosmith848illuminati 4 sure leo!

[@stanislavkostarnov2157]

from a relative who flew heavy bombers, where avoiding contrails was a case of not being shot-down... they would change altitude to avoid or lessen contrails... as there were already certain known altitudes from cloud formations where a contrail is most likely... another thing they did was to limiting how low your engine temps get (since that increases the percentage of "soot" compared to higher temperature burn).

[@michelbrown1060]

As long as planes will use petroleum fuel to travel, they will produce Condensation Trails. .It is part of the combustion process. . Even if they would use Hydrogen as fuel, H2O in vapor will continue Clouds are H2O vapor condensed. .

[@lessi_lex]

Awesome video! Looking forward to seeing some big news on that topic in the future!

[@Ice_Karma]

I remember hearing about the effect the _lack_ of contrails had on the atmosphere during the US nationwide ground stop after 9/11, so I wasn't surprised. I _wasn't_ aware, however, that it had been recognized as contributing to aviation's climate "footprint", so to speak, and that efforts to mitigate them have begun, so it was cool to learn about that! 😻

[@TheSherryBoops]

I love videos about planes. Never flown in a plane and never will. Your voice calms me. I can't explain it but you have a voice that calms me. Thank you. I use to watch DIRTY JOBS because Mike Rowe had a very calming voice. I like to see the white streams behind jets. Thanks so much for all your videos. .~~~~~~Sherry

[@yukonstriker1703]

Look up 'ASMR'

[@stevekirk8546]

Absolutely fascinating - I never knew there was so much I didn't know about contrails! You make these insights so clear and very easy to assimilate - a glimpse of the cutting edge in aviation and aeronautics. Thank you for sharing with us.

[@Mike-bh7sh]

yeah.. I mean - if you can't see it, it must not be there... like air. Contrails exist whether you fly at an altitude that allows them to become visible or not. This is basically a hoax - along with the "studies" that created the "problem" they are trying to solve... I guess a hoax problem, deserves a hoax solution. I caution people from accepting most "information" on youtube... and just because the social media companies are working on a "problem" does not mean it is a real thing... in fact it is more likely not to be a thing if they are.

[@jameshockin3805]

Another great thorough analysis! I watch on my you tube TV all the time so I looked for a way to send some money as a thanks! I love this guy!

[@murraystewartj]

Well, Professor Petter, I came hear and got a lecture on chemistry, meteorology, fluid dymanics, engineering, economics and how international environmental standards are likely to evolve. Whew! There's a lot of the law of unintended consequences at work here and it will be interesting to see what various testinng programs come up with. Just this week I read an article that suggested a correlation between the switch from old, high-sulpher fuels for maritme use (container ships and the like) and increased temperatures due to clearer skies over the oceans. There are also people looking at the possibility of spraying certain chemicals at very high altitudes to increse the albedo of the planet and reduce the amount of solar heating (kind of like the old cloud seeding experiments but for a different outcome). What's fascinating is that our planet and it's atmosphere are such dynamic and chaotic systems and I'm not sure that our current modelling can account for all the variables. Will largely eliminating contrails have the effect af letting more sunlight in and and increasing already record temperatures? We've already dumped enough stuff into our water and atmosphere in a careless terraforming experiment, and I hope that the attempts to fix the mess don't make things worse. I don't care for me, I'll likely be dead but for my kids and grandchild, I'm worried.

[@TucsonDancer]

Thank you. That was very fascinating and informative!

[@chrisindubai]

Definitely a problem to change level because of contrails. Most places I struggle to simply get the optimal level, adding an other factor would be impossible for ATC.

[@NelsonBrown]

I think the assumption is that governments would mandate that ATC support reduced-contrail operations and provide resources for the system upgrades to support it. Farmers' crop yields would increase if contrails were mitigated, so there's a direct economic benefit, too.

[@chrisindubai]

@@NelsonBrown Well, that's very good but the corridors all over the world are packed with traffic already so even now changing level is a pain. Maybe in Europe with reduced separation but that's just a fraction.

[@NelsonBrown]

@@chrisindubai sound like we need Airbus Fellow-Fly and Boeing ACT, put the planes in wake-surfing platoons.

[@paulbunion6233]

look on the bright side. If global warming is as bad as they say, the contrails will start to form only at much higher and little used altitudes so ban EV's to prevent contrails

[@dinoschachten]

Keep in mind that avoiding contrails is particularly important at night - airspaces shouldn't be as congested then.

[@22vx]

Nice work on this vid Petter 👌 thank you for sharing 👍

[@ambds1975]

Thank you once again for the educational explanation!

[@fakename8856]

SAF is such a waste of energy. It takes sooooooooooooo much energy to make this silly fuel it would be much more environmentally friendly to just burn Jet-A.

[@uclajd]

The point is to make air travel more expensive so less people will do it, just like EVs.

[@muhammadishmamabdullah5347]

I am from Chattogram, Bangladesh 🇧🇩 and we used say contrails were rockets flying in the air in our childhood 😅 But nevertheless we always enjoy them, starring at them and dream if could get a ride too one day.

[@NicolaW72]

I can imagine that.

[@markhooper5824]

Very interesting. Contrails explained in depth. Not what I originally thought . So thankyou.

[@ansakyt]

21:50: "exactly this kind of smart" -- spot on! It's time to Do All the Things!

[@sussyscylla3414]

The real answer is so a kid in my class stops calling them chem trails

[@tomaszkarwik6357]

Before learning the correct terminology, I did call them chemtrails Note: I haven't at any time in my life believed contrails to be any conspiracy. I just mixed up contrails and chemtrails in my head

[@Wtfinc]

Except hes not at all wrong. Even if they were 100% water they wouldn’t be wrong. But it does sound ignorant so im with you.

[@sussyscylla3414]

@@Wtfinc its not the logical thing that water is a chemical the guy believes they are isotopes from the government

[@der.Schtefan]

​@@sussyscylla3414Please keep with the facts. They are not "isotopes". I mean, technically every atom is AN Isotope of other atoms with the same proton count. You mean CHEMICAL, but technically every chemical compound, such as air, water, carbon dioxide, is a chemical. You mean artificial mind controlling chemical. And no, the government only uses 100% natural, organic, mind control chemicals.

[@hueginvieny7959]

I've seen real pictures of the switch in the cockpits.. They also have a switch for what effect the Chem trails will have and what companies made the chem trails. It's 100% true and not sad at all that people actually believe Chem trails exist in 2023

[@ntmoucn]

You should do a video on specifically the land resources needed for the production of SAF, in what way the usage of which cannibalizes food production and co2 storage in the form of planting and preserving forests, and whether there would even be enough land for all flights if the environmental impact of the land usage for SAF production wasn’t there, and an overall assessment on how sustainable they are with all of that factored in.

[@chemistrykrang8065]

This is a misunderstanding of the nature of land use, and of modern bio-based fuels. The vast majority of land use is for meat and dairy production. If we stopped eating meat there would be plenty of land for biomass crops and food, with lots to spare for reforestation/rewilding. Biofuels don't have to compete with food production for good agricultural land. There have been huge strides in the use of second generation biomass for fuel production. This is agricultural waste, or crops that can be grown on marginal land not suited to food production. This is very technically feasible, and sustainable... It's just a matter of investment and regulation to make it happen.

[@beatesetzer2441]

She puts so much emotion and expression into this song!

[@MartinDance1]

A really excellent video. You made a complex topic very accessible.

[@hotflashfoto]

I had heard that during the days after 9-11 when the aircraft were grounded, some scientists took the opportunity and did some measuring and discovered some interesting facts about how much of an effect contrails have. I don't recall the details. And now I'm not so sure if that actually happened.

[@haramaschabrasir8662]

I was about to comment the same. Unfortunately I couldn't find sources, but I remember 13-year-old me back then hearing about it in the news.

[@neilpickup237]

Apparently, the lack of contrails over the most densely populated areas resulted in a 2°C increase in temperature over the 3 days when aircraft were grounded.

[@yellowrat77]

My memory serves me well that the temperature delta was +2 daytime and minus 2 nightime from daily mean temperatures at the time. Consistent over the several days where air traffic was forbidden. Since the source news broadcast was US I would think that the data was in Fahrenheit. Most likely a segment on PBS newshour within 2 weeks post that fateful day.

[@neilpickup237]

@yellowrat77 The source I used (Google search on 'how much did the temperature increase after 911') specifically quoted Celsius.

[@gerardjlaw]

I was a little older, so I remember the details. There's a figure which meteorologists measure called 'open pan evaporation rate'. It had been inexplicably decreasing during the last century, then after September 11th, it basically returned to pre-industrial levels within a couple of days. That was the clue that aircraft were causing the drop.

[@jeffdutton1910]

As you pointed out, water and CO2 are in effect, the "ashes" from perfect combustion of a hydrocarbon fuel. They will be present whether or not the water condenses into a con-trail. Water captures IR radiation (heat) regardless of its state (solid, liquid, gas) though not identically in all three states. I have to wonder how much of an effect would be attained by avoiding conditions that allow the formation of a con-trail, compared to not avoiding those conditions. I have to wonder to what extent the initiative is cosmetic rather than substantial. I must confess however, that I don't know enough about the relative IR absorption of the solid vs. liquid vs. gas states to make a truly well-informed opinion, but I suspect that there is a cosmetic incentive at work on some level.

[@cherriberri8373]

The video itself already told you a lot of that though- the non-Co2 effect is between 35% and 50% of the total effect that aviation has on the greenhouse effect, and only about .3% more fuel need be burned to avoid creating contrails. I'm struggling to see where the "cosmetic incentive" comes into this, especially where the motive for airlines comes from. If it didn't work I think the airlines might have something to say about being required to spend a bit more on fuel

[@jeffdutton1910]

@@cherriberri8373 my main point however, was that the moisture is present whether or not a con trail forms, and there is still a greenhouse effect from either way. I wonder if there is any real advantage in not forming the con trail. That would depend on the relative impact of water in the gaseous phase vs the liquid or solid phase. The cosmetic incentive is that if they are seen to be making an effort to reduce their environmental impact, that's good for business regardless of the actual results they can achieve. I believe that in practically every business it is at least as profitable to create the appearance of excellence as to create the substance of it.

[@raulchirea1378]

You're right. It does not matter the state of water (solid, liquid or gas), the effect is the same. In fact, afaik the gas form is the most reflective of infrared light. So, yeah, all this bullshit is a giant grift. :)

[@evas.l.2332]

Very interesting and hopeful! I've recently watched a video on another channel that basically said contails would be too small to be of importance when it comes to the greenhouse effect. While watching it i thought to myself that i could see how it could be a problem. Love your very knowledgeable and well researched take on this. Thank you!

[@lukasdolezal8245]

Yes so 50% effect of aviation is still 50% of 3% totally, so 1.5% which is small importance.

[@stvrob6320]

It still might be true (ie that contrail's effect might be to small to be of any importance).

[@Mike-bh7sh]

And of course if you can't see it - it doesn't exist. I mean if we change altitude to prevent the visible cloud from forming - then all that exhaust/vapor simply doesn't exit the engine... SHOOT - we can save a ton of fuel by simply not having fuel gauges.... if you can't see the tanks are empty - they must not be empty... and we can keep flying. A contrail is formed whether or not you can see the visible cloud. Society is getting scarier... this kind of logic used to only work on 6 year olds.

[@kueflies]

Pretty great showcasing of how much the engineering of efficiency is balancing a number of compromises.

[@DavoShed]

I always think it’s hilariously when people say con trails are pilots are “routinely dumping fuel” Like who routinely throws money away. “Are we over our max landing weight again!”

[@100SteveB]

Thunderf00t did a very interesting video concerning global warming. Interestingly the only time over the last 100 years when the planet showed a trend towards cooling was during the 70's and 80's when we pumped so many other kinds of nasty gases into our atmosphere. Once we started to clean our act up in other forms of pollution we were producing, the real effects of C02 started to become clear - warming the planet. But, of course, we stopped, or drastically reduced those other pollutants for very good reasons - bad air quality at ground level, holes in the ozone layer etc. I can remember when i was growing up that many scientists were predicting the start of a new mini ice age. Just goes to show how finely balanced our atmosphere is.

[@j.mygrant3752]

Science is "cool" -- and global warming can be avoided with "pollution." .. so who ya gonna believe?

[@CyrilleParis]

About the mini ice age : this is a very common misconception. In the 1970s and 80s, no scientists were predicting an ice age. Our memories are confused by something else that was often talked and written about in those days : a mini ice age in case of a nuclear war. A nuclear winter. That's why so many of us have this false memory.

[@Eternal_Tech]

@@CyrilleParis No, it is not a false memory. There were press reports in the 1970s predicting a period of imminent cooling and glaciation, although this conjecture has now been discredited. For confirmation of these press reports, you may read the Wikipedia article entitled, "Global cooling."

[@CyrilleParis]

@@Eternal_Tech Yes it is when you say "many scientists". There were "some press reports", but even at the time, the scientific consensus was worried about global warming, though not having enough evidence yet.

[@Eternal_Tech]

@@CyrilleParis I did not state "many scientists." The original poster used that phrase. My argument was not in favor of supporting the hypothesis of global cooling, but to counter your argument of "false memory." I do not mean to be rude, but you were gaslighting the original poster, stating that he was confusing the issues of global cooling with a nuclear winter. You were telling him that he was misremembering what occurred in the past when according to the historical record, he was remembering quite well. Even though the reports of global cooling have proven to be inaccurate, there were widespread reports of this in many popular media sources in the 1970s and even the 1980s. In addition, you went on to state, "No scientists were predicting an ice age." However, this is simply untrue as there were some scientists predicting an ice age, even though it seems in 2023 that their predictions are incorrect. You owe the original poster an apology for telling him that his memory was false even though it is proven through credible sources that it is true.

[@Ficon]

This is outstanding reporting. Thank you!

[@NicolaW72]

Indeed.

[@paulkoza8652]

Very informative. Thanks Petter.

[@Auto438]

after 9/11 when USA had 3 days no fly sky , the air quality improved so there`s data already

[@Mega_Umbreon]

Hi Pettr, I love all of your videos. Please can you do a video on the merits of the Airbus "average out dual inputs" systems? In a lot of your videos that I watch on the other channel, you mention that the situations seemed to be exacerbated by both pilots inputting opposite inputs and nothing happening. This seems like an unhelpful system and I can't imagine a situation where this would ever be useful over a system that gives one or the other full priority. Thank you❤

[@MartheenCahyaPaulo]

There's a discussion on this topic in Aviation Stackexchange, no official stated reason, just guesses, ranging from not having to manually take priority, alternatives aren't that better as long as procedures are followed (and when they're not, all bets are off) etc

[@jimrobin]

There's a voice that calls out "dual input". The captain should address that issue immediately.

[@mmmdawe]

​@@jimrobin"should" yeah but in extreme stress captain possibly won't even hear it

[@NicolaW72]

Thank you very much for this Lesson in Physics!👍

[@Zickcermacity]

Thanks for the explanations. By the way, you're always Mentour PILOT in my mind! 👍👍

[@juanjmolina]

Love the extensive use for fueler videos. As a former fueler I can tell you fuel reacts very differently to weather conditions. Great video

[@Games_and_Music]

I am actually surprised that they've only started to look into it recently. I've always thought that the contrails were coming from moisture and airpressures, and that the low cloud amount and high altitude was an indication that the trails were to stay visible for long and spread out (like they always do), because i never see the contrails on lower flying airplanes. Sometimes Science moves so slowly, it's always kind of an unsettling surprise, as i usually think that there's always someone out there obsessing over something.

[@cherriberri8373]

Definitely, as of the past couple years it's been shocking to me how many studies have been coming out that seem like complete common sense everyone and their mother already knew about. I guess common sense really isn't that common afterall

[@jwv6985]

This is really good information. Please keep us updated on the results from Airbus.

[@alabamacoastie6924]

As you know, hygroscopic nuclei are ubiquitous at all flight levels, even without the additional nuclei (soot) produced by conventionally fueled jet engines. So, the overall reduction in contrails would likely change minimally, if at all. P.S. I was trained by the U.S. Air Force and worked as a military Flight Forecaster for several years. Excellent and accurate content as always Mentour!

[@victorvastel8028]

Hello ! (Genuine) question : How uboquitous? Can there still be too little condensation nuclei for condensation to occur? Overwise, how to explain sursaturation?

[@Dakiraun]

Yeah, this is fast becoming a new study in how it impacts areas either by heat reflection or retention. They're also now calculating how much tanker and container ships contribute with their trails too (and it's a lot more than they initially realized).

[@cherriberri8373]

I'm glad we are finally actually looking at these very obvious things. We actually have reduced the amount of sulfur allowed inside the fuel for US shipping, which caused a huge, absolutely insane influx of heat to hit the Atlantic, which then heated up to record highs- temperatures that simply reflect the dire nature of the climate crisis. Our oceans aren't supposed to be a hot tub

[@billcurnew6020]

I loved your comment about not responding to conspiracy theorists. We spend all too much time "debating" nonsense and lending credibility in the vein of respecting different opinions. We need to recognize their idiocy, ignore it, and move forward! The world can't wait for them to catch up.

[@ddegn]

*D.A.F.E.* Don't Acknowledge Flat Earthers.

[@markiangooley]

Anyone who believes in chemtrails or a flat Earth has something missing in his (apparently not as often her) life, and gets satisfaction from believing that there’s a secret he knows but most people refuse to think could be true. Polite refusal to debate something that’s merely due to a coping mechanism, with no basis in facts… probably the best way.

[@desdicadoric]

Enjoy your 15th booster my friend

[@tedsommer]

​@markiangooley like assuming that the earth has measurable curvature, or that we're allegedly spinning, wobbling, orbiting and traversing through an infinite vacuum at 1.2mil without any detection is completely normal?....

[@losertocloser]

​@tedsommer are you ok bud?

[@oxigenarian9763]

Outstanding presentation! This is all new to me that there is a potential environmental effect. However, I can't help wonder if, in the sum of all things, it is much ado about nothing....

[@Mentaculus42]

The topic of this video nicely dovetails into several jet engine research projects. Pratt & Whitney’s HySIITE or Hydrogen Steam Injected, Inter-Cooled Turbine Engine project uses liquid hydrogen combustion and water vapor recovery to achieve zero in-flight CO2 emissions, while reducing nitrogen oxide (NOx) emissions by up to 80% and reducing fuel consumption by up to 35% for next-generation single-aisle aircraft. Also the Water-Enhanced Turbofan (WET) project at MTU AeroEngines project is relevant. Additionally by condensing the water vapor, the issue of contrail generation can be significantly minimized by controlling the water droplet size. Probably these ideas will never see commercial applications but they are fascinating.

[@pleappleappleap]

The only reason I knew that contrails are a big deal is that I heard the chemtrail bullshit and then did my own research.

[@salvadormuro7346]

Most interesting. I got into the chemtrail thing a while back and after some observations I was just left confused and decided I didn’t actually know enough to think chemtrails were really a thing in the conspiracy context. You cleared up a couple residual questions id had about that and then I of course learned a lot more. Thanks! A follow up video would be great one day! I’m curious to see how this all pans out especially in regards to how engines and engineers take to the fuel

[@mosca4380]

Its not a "conspiracy"... You are just not looking in the right places. Try doing a search for Cloud Seeding Companies Weather Modification Services. There is literally an entire market for this. The technology was first used during Vietnam in Operation Popeye (Look it up!). This information is not hidden, nor is it in the depths of the dark web. You have just been listening to disinfo agents that confuse the issue and try to make anyone who looks up this kind of stuff get lost and confused in the bs arguments. Franklin Soil & Water Conservation District - In the winter months of 2007 and 2011 this government entity seeded an area in Idaho, USA covering 184,000 square miles to encourage precipitation the following August. North American Weather Consultants - In 2011 this company reported a total use of 96,047 grams of silver iodide to seed eight projects for local government agencies in Utah, Colorado, Idaho, and California. The projects lasted an average of 19 days each and covered a total area of 22,075 square miles. All projects but one were to increase snowfall. That one, in Santa Barbara County, CA was to increase winter rain. NAWC has over 60 years of experience in five continents worldwide. Western Weather Consultants - This company carried out five projects in 2011, seeding a total of 10,000 acres in Colorado, all to increase snowfall. Two of those projects were for the Vail and Telluaride ski resorts, the other three to enhance water supply for the SW Water Conservation District (2) and the Denver Water Department. Weather Modification - This North Dakota company flies 35 planes that execute atmospheric research projects in 19 countries, including the U.S. In 2011 their six U.S. cloud seeding projects covered a distance of 13,495 square miles in Wyoming, California, and North Dakota. The company charges from $500,000 to $20 million for a cloud seeding operation. Western Kansas Groundwater - This public company seeded a 6,766 square mile area in Kansas during the months of Apr-Sep, 2011 to prevent hailstorms and enhance groundwater supplies. It's an annual program that has gone on for almost 40 years in a particularly dry part of Kansas, and has been filled with controversy about its efficacy. The company used dry ice for the first several years as its seeding agent, then switched to silver iodide, and now uses both. Recently the state of Kansas cut its supplemental funding in half, at the same time that the cost of silver iodide increased dramatically, necessitating a decrease in services provided.

[@paul756uk2]

​@@mosca4380spot on. People's opinions are born out of ignorance. It's been going on for almost a century and people think we're the nutters.

[@richardlewis4288]

I loved contrails. IMO much to do about nothing. But great video Petter!

[@bit-tuber8126]

The blocking of heat escaping from below is new to me so this article was news to me.

[@bofor3948]

I used to tell my daughter it was the planes dumping dirty water from the onboard closets. She is a bit older and wiser now, but was ribbing me the other day that when she returned from Germany to the UK and she realised they were going to fly over our home area she went to use the facilities. 😂

[@stephenspreckley8219]

🤣🤣🤣

[@jonchowe]

What causes some contrails to have "bumps" at regular intervals? I see some where each side almost looks like half a DNA strand, with little bumps towards the inside.

[@JaneXemylixa]

Not a pilot, but it might be voitices left behind by wings

[@darwinstubbie860]

They are the finger prints of something he was trying to avoid.

[@kell7195]

747s do this ive noticed

[@curiouscat8457]

It is a visual presentation of "crow instability" - wingtips vortices.

[@harryallen457]

Very interesting. I get asked about contrails a lot.

[@billsmith5109]

As a pilot I’m sure part of your training includes discussing the at least temporary fog that often (always?) occurs inside the aircraft if you experience an explosive decompression. My Father experienced such a decompression in a B-29 at altitudes that in your modern B-737 you just transit on way up or down. I don’t know what the book maximum was but they spent most of their time below 20,000 slowing going up as the ship got lighter. His ship lost a pressure hatch at the front of the ‘tunnel’, this large tube affair they could pressurize and crawl back to the bomb bay or the gunners’ stations. He said his first impression was fire. I think it only lasted a few seconds, but he said in those seconds the obscuration was complete. A licensed P.E., but I’m not sure the Air Force of 1950 briefed crews on the idea of nucleation and cloud formation. He did say when things settled down there was dust everywhere. Every little crack and crevice was blown clean. Ignore published maximum speeds. They flew well less than those too.

[@victorvastel8028]

As someone who's not a plane pilot, I find this fairly interesting. Thanks for sharing.

[@christopherrobinson7541]

The B-29 was driven by four propellor driven engines. The efficiency of these engines decreases with attitude. As the weight of the aircraft was reduced, they could fly higher, but this was not the only factor determining the cruise altitude. If fighter opposition was expected and/or anti aircraft defences, they may choose to fly higher of lower to avoid producing telltale contrails. Also the winds aloft can vary significantly in direction and speed with altitude. Flying with a tailwind can may a huge difference to trackspeed. The B-29s were operated in large formations, with the groups stacked at specific altitudes, which were usually predetermined before flight as changing level was difficult for the whole formation. On occasion this caused some units, at the wrong height, to have a much higher fuel burn, resulting in returning aircraft being unable to return to base. The jetstream also played havoc with bombing from high altitude over Japan, making the Norden bombsight ineffective.

[@maurotassinarizugnitauro2990]

Just to know. What is the percentage of contrail area over the total worldwide cloud coverage?

[@CyrilleParis]

This is not we already have that counts, it's how much we add.

[@maurotassinarizugnitauro2990]

​@@CyrilleParis How much do we add?

[@jamesengland7461]

Very good question. Are we adding 10%? 1%? 0.1%? 0.00001%? At some point, it's too small to even matter.

[@maurotassinarizugnitauro2990]

@@jamesengland7461 Small effect, but big money for someone now and in the future...

[@redboyjan]

​@@jamesengland7461apply that to everything and you end up where we are, facing annihilation. Well done on that line of comment. The climate change denyers thank you

[@filanfyretracker]

I had no clue contrails were this complex though, I thought they were just the airplane version of how a car makes steam from the tailpipe on a winter day. I think the biggest challenge for non normally liquid fuels is their tanks are heavy and take up a lot room, where as fuels like jet fuel can just be stored in sealed up wing compartments. The thing about older seals needing normal jet fuel reminds me of how older diesel engines had issues with Ultra Low Sulphur.

[@Julia-nl3gq]

I thought the same thing about contrails. I also thought that it was just the plane version of a car's exhaust. In my defense I live on the cold Canadian prairies, where you see a lot of cars with their winter exhaust, lol. 🙂 I liked what he said about conspiracy theorists. It makes sense that he wouldn't waste his time trying to tell them anything, because they will just close their ears. They're not interesting in learning about reality, they only read and listen to people who re-enforce their own delusional views. I have a theory about conspiracy theorists. I think they're people who are (to state the obvious) low in intelligence, but also low in self-esteem, and they're attracted to these crazy ideas because of two main reasons - one is that they're not smart enough to be able to think critically about these ideas, and two is that they get a huge self-esteem boost.... ....I mean, they suddenly go from the guy who always been at the bottom of his class to the guy who knows it all, knows what the goverment, big business, pilots, companies, etc., are ''really up too''. That's a big self-esteem boost. I don't know. Maybe I shouldn't generalize. It's just that I've never come across a conspiracy theorist who didn't fit that profile, they always seem to be smarmy know-it-alls who need to feel surperior.

[@MartheenCahyaPaulo]

@@Julia-nl3gq Interestingly, while conspiracy theory is attractive due to the superiority factor, they actually end up making the believer feel even more powerless than before. A society full of diverse self-interest can still find a common ground, but if everything is controlled by shapeshifting lizard there's really no point for the believer to do anything. Of course, they'll still be smug about it because they think their lack of effort is somehow better than those who are willing to do something.

[@cherriberri8373]

But it is exactly that example you gave, lmao. You just aren't thinking about exhaust from a car correctly at all, which shows. Most people don't appreciate how much they trash the planet especially when it comes to things they've normalized and come to expect for one reason or another, like cars.

[@groomlake51]

Mentor is by far the king of content.

[@dennis2376]

Thank you and have a good week.

[@Hans-gb4mv]

One of the problems I am thinking about more and more is how so many people these days think that if we solve the CO2 problem, we would have solved global warming, not realizing that global warming in itself has much more contributors than just CO2. Earlier this week, I saw a video about NOx, now contrails and I know there's even more contributing factors out there, for example hydrogen is also a potent greenhouse gas.

[@uclajd]

CO2 is not a problem. It's a fantasy. It's a religion.

[@niggasjit]

With a whopping 0.00005% of the atmosphere being hydrogen, I cant possibly think its much of a factor 🤔

[@philhawley1219]

Hydrogen cannot exist in the atmosphere. On contact with an oxygen atom it will form a water molecule.

[@ShonMardani]

I believe the Contrails and the Clouds are Transitions of CO2, Dry ice and H2O. The visible material is Carbon part of those molecules. The important numbers are air pressure and temperature required to make CO2 visible, the most important -79 Celsius. Please let me know what do you think, thanks.

[@charlescarmichael1124]

My ex wife thinks they are when the government is releasing aluminum particles into the atmosphere to dumb us down. She thinks they put it in the fuel to be distributed by the engines. Without the airline's knowledge. Aluminum PARTICLES. In the very precision engines!!! 😂😂😂 Someone besides me who knows, please tell us why this is ridiculous!!!

[@normanpain573]

Petter. A most informative video as usual! Interesting to see hydrogen trials being started. Of course, there will have to be much consideration given to the handling of oxides of nitrogen generated by H2 combustion. I think many people forget that N2 is a factor no matter what fuel you burn.

[@handmaidhandmaid356]

@MentourNow Thanks for sharing your time and knowledge with us. I have enjoyed your videos for months. May I suggest that you look further into geoengineering and the associated aircraft used in this warfare (yes, it is a form of war against the climate of a nation or locality)? State legislatures have introduced legislation to stop this destructive and hazardous operation. For example, Rhode Island passed HB 6011 in 2017 - AN ACT RELATING TO HEALTH AND SAFETY- THE GEOENGINEERING ACT OF 2017

[@loctobert9421]

I wonder how significant is this contrail effect comparing to normal clouds and is it really such a big deal. There are so many things we can do for the environment, but with very limited time and human resource. Just wondering and I’m sure there are a lot of qualified people who can do the math.

[@ARockRaider]

it's probably not significant, but some people will likely use it as a reason to drive up costs of travel so only the political elite can travel by air.

[@PicnicAtTheTesco]

Water Vapor has a far higher UV reflective index than other greenhouse gasses, and its formation accelerates with the creation of other GHGs. The goal is to prevent runaway global warming, and so you look at the net impact of transport and not just a single contributor such as CO2

[@primmakinsofis614]

China is the #1 emitter of greenhouse gases in the world, and has been the #1 emitter in the world for 19 years in a row. It has emitted more total greenhouse gases since 1990 than any other nation in the world. But, weirdly, China never gets singled out and blamed for this world-leading contribution by climate activists.

[@primmakinsofis614]

@@PicnicAtTheTesco _The goal is to prevent runaway global warming_ If so, then you might want to have a word with China.

[@PicnicAtTheTesco]

@@primmakinsofis614 I hear this often. Imagine your in charge of a country that has 800 million people living in poverty despite being a super power. Do you think you’d care about emissions, or elevating your people?

[@catallaxy]

I love contrails and will be sad to see them go.

[@greendoorinvestments]

they aren't going anywhere, it's part of weather modification

[@fakename8856]

They aren’t going anywhere, it’s a natural phenomenon that occurs when a turbine engine outputs steam that was clouds before it was super-heated then frozen again after exhausted. Weather modification is not real. Condensation trails are CONDENSATION. Chem trail tin foil hat people are just crazy narcissists.

[@thetowndrunk988]

Hey, you managed to bring the tin foil nut job to the comments section. Awesome.

[@davidwheatcroft2797]

I like the T-shirt! Brown on top! The ADI often tumbles if you pull hard G; it is the last gyro to go, and the first to come back. The gyro compass usually caged to protect it. CAVU skies!

[@cameronproaudio]

Fantastic video. This is going to be the first thing I post when the local contrail whack jobs start spouting off. The amount of technical information and physics presented here is very clear. But like you said in the video, it probably won’t change any minds, at least not for the hard-core ”true believers.” But for people on the fence, it may have some impact.

[@JeanLucCoulon]

With water, you don't need solid/liquid water to create greenhouse effect. Water vapour *is* a greenhouse gas by itself.

[@fakename8856]

Yes, humidity makes up 99% of greenhouse gases, when someone figures out what greenhouses gases (specifically water vapor) is they realize global warming is a scam.

[@markopinteric]

If that were the only problem with this video... The concept of the dew point is also misunderstood in several places.

[@allanmoger1838]

So… if contrails are such a big thing, that logically means regular clouds are a big deal too… I think they are vastly overstating the issue in terms of global temperature but if you buy into one then you can’t put your head in the sand about the other. 😐

[@haramaschabrasir8662]

Clouds (water vapor) are THE most weighing climate gas. That's known for centuries, you don't discover something new here. But clouds are part of a natural balance on this planet, while CO2 that has been dug out of the earth and blown into the athmosphere isn't.

[@ejt3708]

Look for a Nova program from about 2006 which talks about global chilling. Smog cools the planet while greenhouse gasses are warming it. In essence, it says we know so little about atmospheric chemistry that Global Warming would have doomed us all long ago.

[@timfitzsimmons8663]

There has been a specific international focused investigation of clouds & climate for over 40 years. isccp.giss.nasa.gov/about/

[@allanmoger1838]

@@haramaschabrasir8662 no we didn’t learn anything much new. You mention clouds and balance, I would say think about that for a minute - how does that mechanism work? Don’t know? Hmmmm… There’s a lot climate scientists don’t know. Now I’m not arguing pollution is bad, it is, but using CO2 as an analogue for it, and then trying to scare the entire planet into not producing any, is worse. Did you know you breathe 2KG of CO2 each day? Multiply that by 8 billion and do some more big picture thinking. I want to do the right thing by the planet but making China richer isn’t one of those things. Something not mentioned was how expensive clean jet fuel is compared to regular stuff - that 0.3% is still too much for Rayan Air too. 😜

[@cherriberri8373]

I don't know anybody who doesn't realize clouds reflect and trap heat, only those who believed contrails would have zero effect. Clouds trapping heat is just intiutive to me and those around me I guess, we've understood since we were kids that if it's cloudy going into night it will be warmer than usual, and that clear skies meant for a chilly night.

[@rhogaal]

Could you maybe tell us more about these fuel consumption optimization tools? E.g. the one that is being introduced in your airline now?

[@burton48]

Contrails have to me been a beautiful sight in clear blue skies. They have usually been evident of good weather for outside activities, mine being long walks.. This video is most instructive and I learned a great deal from it. I knew they were essentially ice crystals formed at the very low temps of high altitude flying, but I did not know they were considered by some scientists as contributing to climate change. Thanks as usual for your most educational presentations.

[@dh510]

Clouds during the day actually reduce surface temperatures because they reflect radiation from the sun back into space. The same should be true for contrails. The climate is a delicate and usually well balanced system. There even is evidence that the reduction of air pollution (-> aerosol particles) during the last decades lead to increased ground temperatures. If the goal is to cool the atmosphere, the smartest thing to do would be to actually create as much contrails as possible on purpose early during the day and to avoid doing so at dusk and at night. If done right, this strategy might even be able to completely offset the CO2 emissions of air travel, which is responsible for only 3% of total emissions anyway.

[@gailpeterson3747]

Great video, I had no idea that those fluffy contrails were potentially harming our environment. I am also very impressed that Google, NASA, and a few of the airlines are working toward mitigating the negative effect of contrail production. Yes, there is a lot of thinking outside of the box going on and that is exactly what we need. Thanks for providing this insight into this problem.

[@uclajd]

More bullshit from the anti fossil fuels crowd.

[@karlsailor]

Don't worry Google will profit greatly from it

[@XRPcop]

Create a problem and then come up with the solution. It's an excellent business model. 😊

[@CaliSteve169]

There are no contrails. Only weather manipulation via geoengineering.

[@redboyjan]

​@@CaliSteve169hahahahahaha get in your bunker and put your tin foil hat on

[@hairydonuts6024]

Excellent video, as usual. The problem with both SAF & Hydrogen fuels is the high amount of energy used to produce them & hence the amount of carbon their production emits, wich, kinda defeats the purpose. The good news is, low-energy methods have been developed, but it will take a lot of time & investment for them to become the 'norm'.

[@pedtrog6443]

I recall seeing a documentary produced post 9/11 that explored the climatic effect the shut down of aviation over the US had. There was an initially unexplained increase in the 'pan evaporation rate' in some areas. This being effectively a proxy of sunlight intensity at the Earth's surface. This was attributed to the absence of contrails in the sky. There was also about a 2°C increase in the diurnal range of temperatures in areas that had seen the higher rates of aircraft activity. Essentially the day time temperatures were up but the nights were cooler due to the contrails effect of blocking long wave infrared being absent.

[@andy70d35]

Would NEVER trust Google.

[@zbaktube]

Just in the defense of conspiracy theories: One of the component of the U2 jet fuel (Not sure it was the JPTS or an earlier one) was used in pesticides (It was added to keep it combustible in the extreme heights where the U2 was operating). So, in the 1950's the chemtrail was in some cases, true ;-).

[@chrishamilton53]

From what I've read, it isn't degradation that's the problem with low aromatic content fuels, but the fact the don't swell as they do with aromatics. Aromatic hydrocarbons are more aggressive solvents to rubber and some similar polymers than saturated hydrocarbons (or even unsaturated chain or branched hydrocarbons) and dissolve into the rubber causing it to swell up, or with sufficiently high concentrations (ie 100% benzene or toluene) actually start dissolving the rubber into goo. The problem is that once those seals are swollen, they only seal properly while remaining swollen and will thus leak due to shrinkage caused by an absence of aromatic fuel content. (some cases may depend on swelling from the factory, ie the seals won't seal properly out of the box and need a seasoning or break-in periods with fuel flow before they work properly, but I'm not sure how often this is the case or if it's mostly just a matter of old/existing seals that will fail due to shrinkage; ie the latter wouldn't have a problem with SAF if normal jet fuel was never used in the first place). This problem seems fairly straightforward to solve, though: find non-aromatic compounds with similar solvent properties at appropriate blending concentrations. Acetone is one cheap and common example that should work and should reduce soot content even further (it promotes faster and cleaner burn in hydrocarbon blends), but has the problem of limited solubility in high molecular weight saturated hydrocarbons (like what renewable diesel uses and some types of SAF: ie the types derived from hydrogenation of fats and oils rather than esterification as with biodiesel). Other, higher moledular weight ketones might work better for this for that reason (like methyl-ethyl ketone, or even heavier and/or cyclic ketones like cyclohexanone), or other types of organic molecules in general. I just know acetone is particularly aggressive in this regard, so immediately came to mind as a possible solution with low blending concentration needed. OTOH, aside from solubility in fuel blends (especially at low temperatures experienced in flight, and avoiding use of fuel heaters), you also need to consider issues with water absorbsion, and acetone does have the issue of being hygroscopic, and water content would accelerate phase separation, albeit not as much as ethanol. Heavier ketones would also reduce or eliminate this problem, though.

[@tsuchan]

This was fascinating

[@davidcarter4247]

An Australian scientist, who has become wealthy from climate change, once suggested putting sulfur in jet fuel as a way of preventing global warming. He said the sulfur would reflect the sun's heat and the only negative would be yellow tinged skies. This scientist apparently missed the high school lesson on the causes of acid rain. He still is the go-to person on climate change for media outlets and governments.

[@beaudavis3808]

Yeah, I don't trust Australians at all.

[@Ihaveanamenowtaken]

The idea of injecting aerosols in the stratosphere has been considered be the IPCC, they estimated it would cool the planet by 1.5 C.

[@GarageSupra]

Who is this guy?

[@davidcarter4247]

@@GarageSupra Prof Tim Flannery in May 2008. Flannery of now chief counsellor of the Climate Council, a self appointed group that offers a range of climate change solutions. I do not know if sulphur in jet fuel remains on the books.Google and you will find many references to this thought bubble including respected mainstream media. Such as The Age. But maybe not the ABC which tends to disappear Flannery's more ridiculous claims,

[@steveskouson9620]

There is NO controversy over chemtrails! They exist, and I have factual proof. (Water, IS a chemical.) steve

[@flagmichael]

My son-in-law has a T shirt that says, "I keep all my Dad jokes in a Dadabase." Just sayin'

[@backseatcovers]

This is a super informative and fascinating video. 💙💚

[@spvillano]

You anticipated my question about SAF and seals. I don't foresee that being an easily resolved problem though, as that's basically a problem as old as engines themselves. We used jet-A for fuel in our diesel tugs, which caused our usage of motor oil to increase by a fair amount. Still, with enough research, a solution will eventually be found. Then, we'll only have nitrogen problems...

[@fakename8856]

My narcissistic Mom believes in chemtrails, thinks she is allergic to electricity like Chuck McGill, and she needs me to affirm her delusions. She also thinks Earth is flat and we never landed on the moon, despite bringing back reggulathe. These chem trail people are just covert narcissists and they need to “BE THE VICTIM” always. 😂😂😂😂

[@fakename8856]

I am an engineer and love studying lots of types of sciences (including nuclear physics) and my Mom absolutely hates science because she believes the Earth is flat. Narcissism is harmful and dangerous to the people around the narcissist.

[@beakytwitch7905]

As a boy watching aircraft in the skies (late 1950s) I noted that the contrails always disappeared within minutes. Chemtrails, these days? I dunno.... Look on Google satellite view at Guadaloupe, you can find 2 or 3 HAARP antenna farms. Of course those are entirely innocent and have got nothing to do with affecting weather patterns and causing longterm droughts in California. (Do they?)

[@uclajd]

Even worse, some people believe in man made global warming.

[@simplestuff3895]

I get them shouting up at me when I’m up working on radio masts. ‘Is that 5G?!’ Is the usual question. I don’t work on the telecoms networks, I only work on the secret mind control antennas. Nevertheless, I tell them that it is 5G, but I’m safe because I wear tin foil under my helmet. I also advise them that they must stop using their mobile phone immediately, the ones that grace me with a reply always say they wouldn’t get rid of it! 😅

[@paul756uk2]

What makes your mum any less right in believing chemtrails exist and man landing on the moon than yourself in not believing it. Maybe she's better informed than you and is narcissism relevant in these beliefs? Just curious. Personally, I have an open mind about everything. Happy to be proved right or wrong.

[@babyUFO.]

We know what contrails are. You need to learn about chemtrails.

[@ekhaat]

Regarding the fact that contrails form a certain distance behind the engines, isn't the high temperature of the exhaust the reason, or one of the reasons, for the vapor not to form until it has cooled enough behind the plane?

[@minirock000]

"Sublimate" is not "fade away" it means, in this case, to go from a solid (ice) to a gas skipping a form a matter it would normally transition to first.

[@runethorsen8423]

6:20 "research in this field is relatively new" NO it is not, it has been known for decades... but the narrative that water vapor and NOT CO2 is the main greenhouse influencer is just not benefitting your overlords at the WEF.

[@user-kz5ym2gm6b]

If contrails account for 50% of aviation's environmental impact, that tells you how little aviation actually impacts the environment.

[@dougaltolan3017]

No, it dosent, in fact it's the total opposite. CO2 emissions are the main measure of environment impact. If you then double that due to contrails, that means aviation is twice as bad as was originally thought.

[@stvrob6320]

I don't believe that was how that was meant to be interpreted.

[@grandsoleil56]

​@dougaltolan3017 Co2 is plant food wheres the problem

[@dougaltolan3017]

@@grandsoleil56 OK.. Heard this one many many times before... True that in prehistoric times the world has been hotter than now, and with way more CO2 than now, but life flourished at those times. No one with any credibility will argue that. The problem we have now is the rate of change. The current rate of change has never been found to have happened before, not even close. Why is that a bad thing.. From our modern society perspective, have a look for the NASA site that shows how coastlines will change with sea level rise. The sea level is rising, and is expected to be 5 metres higher in about 100 years IF we don't make it any worse. In that time every sea port will have to be moved, most coastal communities will have to move, many cities will have to move. Any one of those is a big ask, all of them, with our current economic model: not a chance! If it was over 1,000 years, not really a problem. But get this, it might well be quicker, 50 years or so. Then there is the effect of shifting agriculture due to shifting climate and weather patterns. The social and economic upheaval of changing which countries produce and consume is going to seriously destabilise world trade. Combine that with mass migration that will make current refugee numbers look tame. It will trigger massive humanitarian crises and likely several wars. And now the ecological consequences. Species will need to evolve in order to maintain a healthy ecosystem. Small, short lifespan organisms can evolve faster. Any that don't keep up will become extinct. Mass extinction *could* cause stagnation and putrifaction, it's entirely possible that nature can be set back to primordial soup stage. Sure, the world has been hotter with more CO2, but to get to that state took millions of years, not a few decades.

[@thewhitefalcon8539]

​​@@grandsoleil56Plants can't eat when it's hot.

[@hans-uelijohner8943]

Vapor cones: The sonic boom is a very fast transition of air from ambient to high pressure, behind it a zone of low pressure is left over, sometimes creating condensation. It is not a transsonic effect but can happen at any supersonic speed.

[@patricemonroe]

I have one problem with explanation, why avoiding contrails is better than extra CO2 burn. That is because CO2 has cumulative long term effect (the global warming is dependend on cumulative CO2 emissions), whereas contrails will remain time limited. That being said, I do admire your positive attitude towards more sustainable aviation industry.

[@philhawley1219]

Global warming and greenhouse gas is simply a myth to control the people. Follow the bullshit and find out who is making the money out of the lies.

[@GarageSupra]

less fuel burnt is less pollution and will cost less for passengers.

[@2Truth4Liberty]

ConTrials are not problem. ChemTrails are. The ChemTrail planes usually do not have seats or carry any passengers.

[@MMID303]

Cargo planes then? Lol

[@user-yg1zj5dz9f]

i listened to an hour or so of the eurocontrol contrail conference....they were talking about flying lower,but if you want to reduce contrail induced by nucleation particles surely this would mean flying higher where there is less humidity

[@user-yg1zj5dz9f]

i'm wondering if there is any point to MRV measuring humidity..other than it would be helpful for us paraglider pilots to know about dew point altitude..are they going to stop flying one day ahead of weather fronts passing?no, but they can generally try to make less sooty nucleating exhaust

[@user-yg1zj5dz9f]

they were talking about co2 equivalence but water vapour reflects multiple wavelengths and co2 absorbs a negligible amount of infra red.different things...and oils create refractive lensing,can that be quantified

[@Nook.Cranny]

Loads of good information!