Impact of aircraft flights on ice melting

[F.Tnioli]

Airplane trail?

Pretty positive that's it.

Normally there would be hundreds of them in various states of dissipation, forming a veil making it difficult to so clearly see single ones:



The usual half-a-CAB "highway" between US and China&Co especially dense, as you can see. However right now, this is not the case. This recent ICAO publication provides one excellent infographic, which shows how international air travel dropped to nearly nada, and is not in any hurry to recover - note the blue line:



Thus, it is no surprise to me we now see those trails as clearly as never before: single trees are always seen in greatest detail when standing single and not in a dense forest, so to say.

I wonder if anybody could any well quantify how much of an increase this particular 2020's development had on the melting momentum increase from GAAC. Personally, i estimate it be ~12% plus-minus couple percent of an increase, averaged over whole Arctic. This is based on published pan evaporate multi-decadal measurements from a number of NH locations initially meant for agriculture but later used to estimate global dimming phenomena; yet this is not even napkin calc - only a rude guess, as i don't even fathom how to do one in this case. If someone can anyhow improve on that - please do.

[ArcticMelt2]

Airplane trail?

Pretty positive that's it.

It is pretty telling that a lone airplane contrail is a noteworthy development in 2020 amidst the background GAAC. It's almost like the lack of planes is having a real impact. !

There are at least 2 intersecting tracks. One of the flights looks like this one.

https://flightaware.com/live/flight/CCA990

[ArcticMelt2]

Airplane trail?

Pretty positive that's it.

Normally there would be hundreds of them in various states of dissipation, forming a veil making it difficult to so clearly see single ones:

Thank you very informative.

[Viggy]

Airplane trail?

Pretty positive that's it.

Normally there would be hundreds of them in various states of dissipation, forming a veil making it difficult to so clearly see single ones:

This would make for a fascinating research paper! A prolonged, one time event (hopefully) to get data on how directly we affect our environment (positive or negative feedback, notwithstanding)

[F.Tnioli]

Thank you very informative.

You make me blush, man. %)

Here's one extra thing to perhaps complete the story:



See, up to ~1990s (great many) folks flying from US to China were going sort of "around" ESS and such, but the more long-range airliners entered service, the more "over pacific half of the Arctic" direct flights were happening. Now, i'm sure you know how in 2000s and especially 2010s atlantic half of minimum extent was giving up way faster than pacific side, in general. Hardly a coincedence. Further, we now see how this melting season, pacific half, especially russian side of it, is vanishing fast (relatively slow american side melt is significantly due to early-season cold anomaly there). Hardly a coincedence, too.

The sad part is (my bold): "The scattering properties of the ice crystals in contrails and natural cirrus are different and result in differences in their radiative forcing. Figure 4 illustrates the effect of ice particle sizes and habits of contrails, contrail-induced cirrus, and natural cirrus on the solar and infrared radiation. The influences of particle effective size and habit on radiation are stronger for solar radiation than for infrared radiation, particularly for thicker cirrus clouds" (page 11 of this paper). Thus, we won't see as much extra cooling once it's (mostly) dark in a given region of Arctic towards the end of the melting season as we see extra melt now at high insolation. In other words, for the ice, it's better when lots of planes are flying over it - and now they don't.

[ArcticMelt2]

Thank you very informative.

Here's one extra thing to perhaps complete the story:

I wonder if you have any information on how fewer planes fly over Antarctic waters, compared to flights over the Arctic seas?



If you look at https://flightaware.com/ now, then this number of flights can be 2 times less. Currently, there is an aircraft over the North Pole, over the Canadian Yukon, and an aircraft in the Drake Passage area. Though I'm not counting the busiest route over Greenland.

Antarctic ice is currently in 8th place.

It may be true that aircraft have a significant effect on the melting of ice due to the deposition of soot on the ice from the combustion of fuel in engines or due to the greenhouse effect from an increase in the concentration of water vapor in the upper atmosphere. This effect may be stronger than aerosol cooling.

[ArcticMelt2]

Topic about the influence of aircraft flights on ice melting.

[oren]

Cross posted from the melting season thread.

What is it in the East Siberian Sea? That wasn't in yesterday's photo.

Clouds? Airplane trail?

[oren]

Airplane trail?

Pretty positive that's it.

[oren]

It is pretty telling that a lone airplane contrail is a noteworthy development in 2020 amidst the background GAAC. It's almost like the lack of planes is having a real impact. !

[ArcticMelt2]

The intensity of flights over Antarctic waters is really very low. It is orders of magnitude less than the number of flights over the Arctic seas.

https://www.popsci.com/airplane-tracking-mh370-adsb/

Data from spring 2017.

Over a 62-hour period, Aireon's satellite-based tracking system traced the routes of 17,000 aircraft—including some in areas that Air Traffic Control has never been able to monitor before.Aireon

This is probably really one of the main reasons for the weak melting of southern ice compared to northern ice.

[ArcticMelt2]

Another image from 2015.

https://spaceflightnow.com/2015/05/07/space-based-airplane-tracking-demonstrated-by-esa-satellite/

An experimental receiver aboard a European satellite has picked up signals from more than 15,000 aircraft in the last two years, paving the way for future missions that could track global commercial air traffic from space.

[ArcticMelt2]

Airplane trail?

Pretty positive that's it.

Normally there would be hundreds of them in various states of dissipation, forming a veil making it difficult to so clearly see single ones:

This would make for a fascinating research paper! A prolonged, one time event (hopefully) to get data on how directly we affect our environment (positive or negative feedback, notwithstanding)

There has been a lot of research and back and forth in this area.  Twenty years ago, aircraft vapor trails were thought to have a net cooling effect on the planet (increasing planetary albedo).  Now the consensus seems to be that they have a net warming effect (taking into account IR absorption etc).  I have never been comfortable with that latter conclusion -- but then again I have not 'done' the science.

It looks like you are right. A shortage of aircraft over the Arctic this summer is saving the ice rather than accelerating its melting

[kassy]

A shortage of aircraft over the Arctic this summer is saving the ice rather than accelerating its melting


That statement is possibly not true.

I gather you are looking for some short term effect but basically that is minimal.

What would be the input if you calculated that for 2020? (effect from most traffic of last years compared to 0).

If you had this 2020 contribution it might be interesting to compare it to airplanes overall contribution to global warming just from fuels used so far. That cumulative effect will be bigger.

I don´t know how big the spring drop was vs the examples in posts 10 and 11 but there should be some interesting science coming out of our current natural experiment. I am interested in all the water planes dump at really big heights and what happens when it´s not there. Not sure that that paper is actually going to come but it´s not going to be about the direct effect of airplanes on the ice either.

The more accurate statement is:
A shortage of aircraft over the Arctic this summer is irrelevant for the ice.

Or you can verify the current state saving on the melt thread.

[ArcticMelt2]

A shortage of aircraft over the Arctic this summer is saving the ice rather than accelerating its melting


That statement is possibly not true.

Why, then, in Antarctica, on the mainland or in the seas, ice loss comparable to the Northern Hemispheres is not observed? After all, planes and ships fly and swim there dozens of times less often.

[ArcticMelt2]

I gather you are looking for some short term effect but basically that is minimal.

What would be the input if you calculated that for 2020? (effect from most traffic of last years compared to 0).

If you had this 2020 contribution it might be interesting to compare it to airplanes overall contribution to global warming just from fuels used so far. That cumulative effect will be bigger.

I don´t know how big the spring drop was vs the examples in posts 10 and 11 but there should be some interesting science coming out of our current natural experiment. I am interested in all the water planes dump at really big heights and what happens when it´s not there. Not sure that that paper is actually going to come but it´s not going to be about the direct effect of airplanes on the ice either.

The more accurate statement is:
A shortage of aircraft over the Arctic this summer is irrelevant for the ice.

Or you can verify the current state saving on the melt thread.

It is difficult for me to give an exact estimate of the effect, but it seems to be significant. At least two facts can be cited here:

1) Before the collapse of the USSR, the number of flights over the Siberian side of the Arctic was minimal. And then the ice really melted badly.

2) The most intense flights near the coast of Antarctica are between Chile and Australia. And this region is indeed the warmest.





So I think the effect is real, and it accelerates warming by several tens of percent.

[ArcticMelt2]

This map also clearly shows that the route between South America and Australia is the most frequently used route off the coast of Antarctica.

[ArcticMelt2]

This is obvious, Africa is the poorest continent in the Southern Hemisphere, and they fly there much less often than to Australia or South America. It's simple.

In addition, Africa is much farther from Antarctica than the other two continents, and planes fly there much farther from the ice.

[kassy]

A shortage of aircraft over the Arctic this summer is saving the ice rather than accelerating its melting


That statement is possibly not true.

Why, then, in Antarctica, on the mainland or in the seas, ice loss comparable to the Northern Hemispheres is not observed? After all, planes and ships fly and swim there dozens of times less often.

The Arctic is a sea surrounded by land and Antarctica is a really large block of ice surrounded by oceans mostly land but with lots of annoying channels. We have sections where you can read up on both. Also there are not that much reasons to fly or sail to Antarctica because it is a big block of ice.

When weighing effects you need to work out how big they are and whatever does or does not fly or boat around Antarctica really does not influence the place.

[oren]

I think you need more science to establish a linkage between flights or lack thereof and intensity of ice melt. (Perceived) correlation is not necessarily causation. Has there been any paper quantifying the effect of flights on Arctic atmosphere, insolation, cloudiness, etc.?

[ArcticMelt2]

I think you need more science to establish a linkage between flights or lack thereof and intensity of ice melt. (Perceived) correlation is not necessarily causation. Has there been any paper quantifying the effect of flights on Arctic atmosphere, insolation, cloudiness, etc.?

Such work did not come across, except for articles that aviation is responsible for 5% of global warming and has a very rapid development.

https://www.transportenvironment.org/what-we-do/flying-and-climate-change

Aviation emissions have more than doubled in the last 20 years and the sector is responsible for an estimated 4.9% of man-made global warming.

But it is interesting that they write that transpolar flights became widespread only in the 21st century.

https://pdfs.semanticscholar.org/5888/826c073dc545442e93eb6a342780991129ee.pdf

10 thousand flights a year, this is 2 million tons of burned jet fuel over the Arctic or hundreds of thousands of tons of soot deposited on the sea ice.

[F.Tnioli]

I think you need more science to establish a linkage between flights or lack thereof and intensity of ice melt. (Perceived) correlation is not necessarily causation. Has there been any paper quantifying the effect of flights on Arctic atmosphere, insolation, cloudiness, etc.?

None i currently know of. Not specifically about the Arctic, that is.

The subject is touchy. And i can explain to you why. Look, we know that past-2012 seasonal minimum ice volume trend has not only stopped, but even reversed. We know it happened despite ever growing GHG concentrations, despite all the positive feedbacks in play by 2012 which were much responsible for the acceleration of said trend pre-2013, and despite ever growing global surface temperatures and Arctic amplification, none of which were suddenly "gone" after 2012. Still, we see this:



This little graph is partially my creation, namely i added dots for minimum volumes after 2012, CO2 content numbers on top, and slowly gaining-minimum-volume line for years after 2012.

I am quite sure you know the scale of energies involved in those processes. In short, they exceed whatever kinds of energy mankind generates, every year. This kind of trend reversal, given circumstances, can not occur without extremely powerful new factor in the post-2012 ASI affairs.

To this date, the only known to me technology which could _possibly_ introduce such factor - is welsbach seeding. You can easily find corresponding patents by Hughes Aircraft Company filed in some 1991, if memory serves. The only known to be carrier of it into the Arctic - are those thousands of flights, with notable increase of their numbers exactly during Arctic melt season (as most people prefer to take vacations and travel not in winter, but in summer).

Lots of artificial nonsense about "chemtrails" in the net very much looks like indeed noise made on purpose to hide something. Way too much "obviously ridiculous" websites and statements around. For example, in lots of places you will find them "chemtrail crazies" stating that special tanks and nozzles are installed into civilian aircraft to produce the trails. In reality, jet fuel can simply be altered itself, adding required substances into it. And if you'd try to find out _what_ exactly are fuel additives for modern western types of most commonly used jet fuel - detailed formulae - all of a sudden you will "hit a wall". The information is nowhere to be found.

Now if Welsbach takes place any significantly, it can not take place in the open: public reacts very badly if they discover some "governments" and "companies" spread unknown chemicals over their heads. Aluminium oxide, for example, is known to cause some very bad health effects. Not to mention all the uncertainties about such methods in principle, especially long-term.

Indeed, i've seen recordings of US court hearings of "people vs state" kind, where citizens were presenting results of laboratory analysis of surface water and snow in places they inhabit, demonstrating enourmous violations against maximum allowed levels of certain pollutants as well as showing that the only source of that pollution could be with precipitation / air particles, such as taking sampels from high mountain regions with no kinds of human business existing anywhere near or uphill.

This is why, i'm plenty sure, there are no honestly made, scientific papers on the subject.

I'd be extremely grateful if you could provide any other, however hypothetical, explanation to what we see in the above graph, Oren. But so far, the line "contrails have massive cooling effect" is kind of "good manners" way for people who know a bit or two about what's going on to discuss related matters, you see. Especially in public.

P.S. I've sent this graph to Neven and some other gentlemen, last year. Noone can provide any alternative ideas as to why it happens. But here's one little detail: since then, the copy of this graph which i uploaded to one of image sharing services - was deleted. That service never deletes  user uploaded pictures in less than a year, at no circumstance, by its scripts. Someone deleted it by hand. This is by far not the only sign i see around that the subject is more than "touchy" - it's actuvely supressed. Personally, i'm quite sure such supression is indeed required in any widely watched / heard (by public) mass media, but overdoing it, in the same time, - i think is counter-productive. But we have what we have.

[ArcticMelt2]

The subject is touchy. And i can explain to you why. Look, we know that past-2012 seasonal minimum ice volume trend has not only stopped, but even reversed. We know it happened despite ever growing GHG concentrations, despite all the positive feedbacks in play by 2012 which were much responsible for the acceleration of said trend pre-2013, and despite ever growing global surface temperatures and Arctic amplification, none of which were suddenly "gone" after 2012. Still, we see this:



This little graph is partially my creation, namely i added dots for minimum volumes after 2012, CO2 content numbers on top, and slowly gaining-minimum-volume line for years after 2012.

The simplest explanation for the interannual variability of the summer ice area is the connection with the solar cycle. 2007, 2012 and 2020 lie well in the solar maximum and minimum regions.



Probably solar activity switches some processes in the atmospheric circulation. By the way, the strongest El Niños happen in about 13-16 years, which is equal to the solar cycle.

I wonder why you are so sure about the prevalence of the cooling effect from aircraft?

After all, aviation fuel is a fuel of the highest purity, and the sulfur content there is clearly much less than in car fuel.

At the same time, it is well known that the combustion of aviation kerosene leads to the formation of soot. This fuel is considered to be dirtier than methane or hydrogen.

[F.Tnioli]

Very curious why you said what you just did. I'll answer 1st, then provide few statements which i hope you will find possible to comment, ArcticMelt2.

I am so sure about prevalence of cooling from contrails because i've spent serious amount of time digging into the matter. The information i provided in the above post is but a tip of an iceberg of knowledge i accumulated. May i offer you to research the subject of global dimming in general, and reported role of contrails in it in particular. Warning: you will definitely find contradicting statements and papers if you would try, and you will need good methods of deducting which ones are false, if the goal is to obtain any good knowledge. It will most likely take months if not years to make any good progress in understanding it, - at least, took for me.

As for SO2, it was proven much inferiour for welsbach seeding in compare to Al2O3. 2...4 times inferiour by mass, if memory serves. Lowell Wood did detailed research about it, but presently i don't think his results are available for the public. They were several years ago, but since then were removed from public access as far as i can see.

Now, few things i'd like you to comment for me - very curious to see what (if any) you would have to say:

- solar cycle is not "13...16" years, which you stated seeing you used word "equal", - it's 11 years;

- we know that "... solar luminosity is an estimated 0.07 percent brighter during the mid-cycle solar maximum than the terminal solar minimum". I.e., the difference is less than 1/1000th. Blaming solar cycles for major, and more importantly unprecedented and clearly non-rhythmic (seeing back to 1980s and 1990s) changes in minimum sea ice volume is therefore massively wrong;

- while it's true that short-wave radiation (UV, X-ray) has major, solar-cycle variable effect on Earth's upper athmosphere, any idea that this process through some unknown cause-effect chain would cause the revert of the trend i mentioned crashes into the same argument: if this would be the main cause, then we would clearly see 11-year pattern in minimum arctic sea ice: the loss would occur in "dips and recoveries" manner, or at very least "dips and pauses", over the decades since 1979. But we don't. This reversal is one unique event in the history of satellite observations, so massive that it also is clearly reflected by extent annual minimums as well, with 2012 to this day holding the minimum record.

[oren]

I don't subscribe to either of these speculative explanations.
Weather variability and the loss of MYI can easily explain  the variability of volume between years anf the relative slowdown after most MYI has gone from the Arctic.
In addition, looking just at minimum volume is not informative enough. 365-day average volume hit its lowest in 2017, not 2012.

I am not saying flights have zero effect on the Arctic - but such an effect needs solid scientific backing.
As for secret seeding programs, I can say with certainty these do not exist. Too many governments, too many airlines, too many scientists, too many private amateurs, for this to go on unreported, unleaked and unnoticed.

[be cause]

AM2 .. 10,000 flights , 2million tonnes = 200 t per crossing . Even a Boeing 747 would travel >16,000 km on that fuel . Sums don't add up ! b.c.

[F.Tnioli]

No, Oren, neither weather nor MYI loss is enough.

The latter is one big contributor to what we had so far, i agree with that much. But not the main cause. MYI loss happened because extra energy in Arctic surface layer entered and melted it. We know where that energy came from, and after 2012 there is even more of it, not less. In the near absense of MYI, that energy, should it keep coming in in ever growing amounts, would unavoidably result in further rapid loss of minimum volume and extent: you know full well that as long as any ice remains at the surface, that energy can't be spent to anything else, like extra evaporation or surface temperature increase. But this further accelerating melt at the minimum did not happen. Conclusion: there was significant decrease in overall amount of energy reaching Arctic surface layers, net total per a melt season. Despite all the drivers which remain in action to pump more and more of it there. Something has to block that energy flow after 2012. Absense of MYI can't do it.

As for weather variability, it's sure there, but it always was there. The beauty of that graph is that it contains data all the way since 1980. And we see what weather can do, by seeing the scale of resulting variability: in 1980s, the trend was "slow decline", and fair amount of variability then demonstrates how much it can do when Arctic is more or less balanced energy-wise. In 1990s, the trend changed to more rapid loss of minimums, and as you can easily see size of year-to-year swings decreased in compare to 1980s: this is because peripheral seas began to have much harder time about getting more ice due to freeze-favorable weather simply because of amount of heat stored around. In 2000s, the trend became very rapid loss, and due to same but more prounounced factors weather variability played even less role than in 1990s. This all is pretty clear from merely eye-balling that graph, so strong are the forces involved. If those observations would be expressed in numbers and percentages, some truly stunning figures would appear.

365-day average volume reaching lowest ever in 2017 is likely due to less effects during winter times. I gathered some information about volume of production of Al2O3 nanometer-sizes particulates (which is being done on indeed industrial scale) and corresponding costs. The thing is not free to make nor to distribute. Nobody who would be able to pull that off would have the freedom to just keep doing it with same intensity and amount all year long. One must understand that welsbach seeding was never intended as any kind of permanent solution, too. Even its creators noted that it's a temporary measure, one which also further worsens long-term conditions at that. The main goal is not to "heal" Arctic nor "revert" AGW; merely to "buy some time" both in terms of postponing irreversible BOE state (which would have much damaging effects all around the globe) - trillions USD damages are at stake here; and also to "prevent public worry" for same "some time", which mainly requires an "impression" that ASI is still there and doing "OK". Extent does not fall, major publications note "recovery"? Good enough, "job well done".

As for "unreported", it did not go unpreported, Oren. I've seen reports - by airline pilots, scientists, private enthusiasts aplenty. Testimonies in courts. Detailed papers about it. But i am telling you, it's being supressed. Publications vanish. Recordings disappear. I'd give you plenty examples, but they are not around anymore. I have some saved on my drives, but you know, "i can take the hint" - no intention to rock this boat so much by republishing them. Mere scale of the campaign dedicated to make clowns out of anyone who even dare use the term "chemtrail" in any manner - indicates to me it's best not to play hero too much. So i'm sorry, but you'll have to dig yourslf if you'd want to find such reports, leaks and notices. I assure you, quite many still can be found.

Good luck.

[bbr2315]

I strongly agree with F. Tnioli. The information that isn't "contrails whoooooo no chemtrails, spoooooky" is completely suppressed and the field is made to look like a fringe lunatic science. I don't think it is.

It is very sad to see the denier efforts from the right end of the spectrum now matched by efforts by those on the left to crush science & discourse.

<Part removed. O>

[SteveMDFP]

I gathered some information about volume of production of Al2O3 nanometer-sizes particulates (which is being done on indeed industrial scale) and corresponding costs. 

Well, if some vast conspiracy were working to surreptitiously engage in geoengineering, adulterating jet fuel would probably be a good approach.  But aluminum oxide won't work.  It's an abrasive, and would rapidly destroy jet engine turbines.  I doubt any metal could be used.  Sulfur would have advantages, but that's being decreased, not increased.

[F.Tnioli]

Abrasiveness is common for bulk alumina compounds, yes. However, it's not those compounds i was talking about. It's no secret that "... properties of bulk alumina that allow it to be such a versatile element in the industry are different from those of its nanoparticles". And as can be seen from other applications of the matherial, industries produce different shapes of Al2O3 nanometer-scale particulate - including spherical ones.

Most commonly used method of making the stuff, which is laser ablation in inert gas, produces quite very smooth surfaces - at scale involved, surface tension is very efficient. This and well smoothed fuel lines are simple and (relatively) cheap methods to prevent wear and tear good enough. And with AL2O3 melting point being over 2k degrees C, things remain well-shaped through and through in the engine, as jet engines of modern airlines are well known to have maximum burn temperature at or below 2k C.

SO2 was ruled out of any perspective GE applications fairly large number of years ago - not because it's way less effective as noted above, but also because large scale implementation leads to obvious problems with acidity. H2SO4, which forms as SO2 freely reacts with H2O, is one very agressive substance. Acid rains were enough problem in the past for WH folks not to repeat the mistake. Also, you can't easily have SO2 in jet fuel as fiel burning always occurs with substantial presense of H2O from outside air - you'd lose large amount of SO2 exactly as it happened in old-style coal plants responsible for much of acid rains around the globe. But Al2O3? Easy peasy. Reacts with nothing short of strongest bases, which are of course absent up there.

Those are not the only but already more than sufficient - and rather simple - causes to not see SO2 used for the job at the required (for desired effect) scale.

[oren]

I am willing to read references on the effects of airline flights on the Artic, hopefully scientific references, or calculations by members.
However, I am unwilling to entertain chemtrails, conspiracies and hidden campaigns that no one knows about. Sorry, don't be offended, but not on this forum.

[HapHazard]

I agree with oren. Nebulous claims of unprovable "conspiracy theories" don't belong here.

[bbr2315]

I agree with oren. Nebulous claims of unprovable "conspiracy theories" don't belong here.

Is it really nebulous, though? I mean AGW is literally seen as a conspiracy theory by a majority or plurality of the US population and it is not urgent enough for a majority or plurality most anywhere else to care.

I don't think it is so much a conspiracy theory as an area of limited research where spurious claims can be justified by studies that use limited or incomplete data. How long did it take until GHGs were accepted as warming agents? And what about CFCs and the ozone hole?

My point here is that it may not be so much a conspiracy as it is human stupidity / limited knowledge. It is true there are entities who ARE interested in discrediting AGW / etc so it follows that research into related fields would also be rife for misinformation. But it is also true that scientific advancement into climate research / clouds / aerosols is generally limited to failed predictions and doodles of hockey sticks without any nuance or room for narratives that are not the status quo (status quo narrative: "it is getting hotter everywhere forever and ever and the world is warming and the ice is melting and this is something we can fix" -- this is st*pid and untrue but it is literally the message most climate scientists agree on!).

It is easy to point to conspiracies when in fact humans are actually incredibly stupid and misinformation is often created and perpetuated due to accidents, not malice, and I would argue this is probably the MOST frequent way disinformation occurs.

[F.Tnioli]

I am willing to read references on the effects of airline flights on the Artic, hopefully scientific references, or calculations by members.
However, I am unwilling to entertain chemtrails, conspiracies and hidden campaigns that no one knows about. Sorry, don't be offended, but not on this forum.

Nor am i.

Do you have anything to continue the discussion of any other possible causes of the trend reversal i mentioned prior with? I do not see a single word from you regarding my objections towards your ideas of MYI and weather influences, in particular.

Or THAT is also "conspiracy theories" now?

The ice of my trust gets a little thin here, old friend...

[kassy]

So there was this year with a big crash and then some recovery from that. So you ploy the yearly values and draw a line but that is not how that works.

If you look at a youtube movie of the ice over the years you can see it change to now where we only have a failing skeleton of bigger ice left. The trend will not keep reversing and hence you don´t need your theory.

 

[F.Tnioli]

So there was this year with a big crash and then some recovery from that. So you ploy the yearly values and draw a line but that is not how that works.

If you look at a youtube movie of the ice over the years you can see it change to now where we only have a failing skeleton of bigger ice left. The trend will not keep reversing and hence you don´t need your theory.

I did not talk about "single year with a big crash". I talked about a trend, and about how that trend was reversed. Please note that "trend" means a number of years forming clear progression - like decline or increase. And that number can not be "1" or "2" or "3". It takes 5+ years to even start a trend. One or two years with big dips happened even back in 1980s as shown on that same graph, but there was no jaw-dropping declinining trend like there was in 2000s. Why trends are important and single years are not? In short, because this thread is about aircraft contrails influence on sea ice, and to explain my opinion on that subject, an argument was made which requires to observe certain trends, but not single years.

Your inability (or worse, an act of intentional faked ignorance) to grasp even such most basic words - such as "trend" - makes me unwilling to comment your post in any further detail. Sorry. 

[Hefaistos]

...

- while it's true that short-wave radiation (UV, X-ray) has major, solar-cycle variable effect on Earth's upper athmosphere, any idea that this process through some unknown cause-effect chain would cause the revert of the trend i mentioned crashes into the same argument: if this would be the main cause, then we would clearly see 11-year pattern in minimum arctic sea ice: the loss would occur in "dips and recoveries" manner, or at very least "dips and pauses", over the decades since 1979. But we don't. This reversal is one unique event in the history of satellite observations, so massive that it also is clearly reflected by extent annual minimums as well, with 2012 to this day holding the minimum record.

This is OT, but is an interesting topic in the more longterm developments only, i.e. the so called Milankovich cycles (41 - 100 k years).
And yes, there is an almost perfect match between summer insolation and the changes in ice volume.
See Roe, 2006.
"In defense of Milankovitch"
doi.org/10.1029/2006GL027817

From the abstract: " The Milankovitch hypothesis is widely held to be one of the cornerstones of climate science. Surprisingly, the hypothesis remains not clearly defined despite an extensive body of research on the link between global ice volume and insolation changes arising from variations in the Earth's orbit. In this paper, a specific hypothesis is formulated. Basic physical arguments are used to show that, rather than focusing on the absolute global ice volume, it is much more informative to consider the time rate of change of global ice volume. This simple and dynamically‐logical change in perspective is used to show that the available records support a direct, zero‐lag, antiphased relationship between the rate of change of global ice volume and summertime insolation in the northern high latitudes...."
The attached figure compares the insolation anomaly (green curve) during June at 65 N with the best fit of change of ice volume to the orbital variations (black curve). Two metrics of ice volume are used, and show similar results.

Paper is open access.

[interstitial]

F. Tnioli
extent and volume are two different things.



EVERY INDICATION IS VOLUME HAS DROPPED AND CONTINUES TO DROP. No evidence of stopping some variability but new record low last year.


Extent has not gone lower than 2012 but claiming recovery is a poor characterization. 2012 was substantially lower than previous years. Several years since then have broken 2nd place extent record. What is it 3 or 4 years broke previous 2nd place records and the lows are not returning to previous levels. They are clearly still trending downward. Any other characterization is a deception.


I do not know about chemtrails but your premise is FALSE.

[ArcticMelt2]

I think you need more science to establish a linkage between flights or lack thereof and intensity of ice melt. (Perceived) correlation is not necessarily causation. Has there been any paper quantifying the effect of flights on Arctic atmosphere, insolation, cloudiness, etc.?

By the way, there really is a scientific work that flights over sea ice accelerate its melting.

https://link.springer.com/article/10.1007/s10584-012-0462-0

The effects of rerouting aircraft around the arctic circle on arctic and global climate

Climate data suggest greater warming over the Arctic than lower latitudes, and the most abundant direct source of black carbon and other climate-relevant pollutants over the Arctic is cross-polar flights by international aviation. A relevant question is whether rerouting cross-polar flights to circumnavigate the Arctic Circle reduces or enhances such warming. To study this issue, a model accounting for subgrid exhaust plumes from each individual commercial flight worldwide was used with 2006 global aircraft emission inventories that treated cross-polar flights and flights rerouted around the Arctic Circle (66.56083 °N), respectively. Rerouting increased fuel use by 0.056 % in the global average, mostly right outside the Arctic Circle, but most of the associated black carbon and other emissions were removed faster because they were now over latitudes of greater precipitation and lesser stability. Rerouting also reduced fuel use and emissions within the Arctic Circle by 83 % and delayed pollutant transport to the Arctic. The Arctic reduction in pollutants, particularly of black carbon, decreased Arctic and global temperature and increased Arctic sea ice over 22 years. Although the slight increase in total CO2 emissions due to rerouting may dampen the benefit of rerouting over more decades, rerouting or even partial rerouting (allowing cross-polar flights during polar night only) may delay the elimination of Arctic sea ice, which will otherwise likely occur within the next 2–3 decades due to global warming in general. Rerouting may increase worldwide fuel plus operational costs by only ~$99 million/yr, 47–55 times less than an estimated 2025 U.S.-alone cost savings due to the global warming reduction from rerouting.

So the question can be closed.

[ArcticMelt2]

More estimates from the description of the paid article:

https://www.earthisland.org/journal/index.php/articles/entry/aviations_melting_the_arctic_researchers_find_a_mind-blowingly_cheap_soluti/

new research shows that simply rerouting plane flights around the Arctic will delay Arctic sea ice melt, prevent 1.75 to 2 percent of global warming

So if you were to reroute planes around the Arctic: “Due mostly to Arctic cooling, global surface temperatures decreased by…1.75–2 % of net global warming (0.7–0.8 K) to date.”

Considering that the area of sea ice in the Arctic during the summer solstice is 10 million km2, or also 2% total surface area of the planet, it seems that aircraft flights over the Arctic are one of the main reasons for the rapid melting of sea ice.

[oren]

Thank you AM2, finally some published science in this thread. I hope for more.

[El Cid]

I think that you should not concentrate on fuel burning & soot but much more on the cloud effect if there is any.
I do not think that this question is closed. As far as I know we still do not know for sure what effect aircraft cloud forming has on our climate

[ArcticMelt2]

By the way, the full version of the article

https://web.stanford.edu/group/efmh/jacobson/Articles/VIII/PolarReroutingClimChang12.pdf

It gives much larger numbers of flights over the Arctic Ocean in the 21st century. Not 10 thousand, but about 40 thousand every year.

Based on this analysis, 263 O-D markets had at least one percent of their flights meeting
the criteria above in 2006. The number of flights between each origin and destination in
these markets was 82,602. Of these, 40,399 (or 0.129 % of all 2006 worldwide commercial
flights) were cross-polar. The remaining 42,203 were circumpolar (flying around the Arctic
Circle). The number of 2006 cross-polar flights meeting the criteria here (40,399) is less than
the number of 2006 cross-polar flights from Fig. 1 because the source of flight inventory
data for Fig. 1 (flight schedule data from Innovata, LLC) differed from that of the Volpe
baseline inventory developed here for 2006 (Wilkerson et al. 2010).

The contribution of emission from aerosols is also taken into account there.

[ArcticMelt2]

Note that the work was written several months before the catastrophic melting of 2012. It looks like no one really wants to stop the melting of the Arctic ice. Otherwise, commercial aircraft would now be flying around the Arctic ice. As it is written in the work, the costs of flying around the Arctic are hundreds of times less than investments in renewable energy. The public is more concerned with the depletion of fossil resources than with global warming. In this regard, governments welcome the melting of the Arctic ice as an incentive for the economic development of the Arctic.

[F.Tnioli]

Thank you Oren, and thank you ArcticMelt2, for not answering my queries above despite my specific requests for you both to do so. This shows clearly i am dealing with nothing else, and nothing but, hypocrisy here. I know this is strong accusation and nothing pleasant to hear, gentlemen; it brings me no joy to attack anyone's ego, and the point is not to do so. But rather, the point is to present the only logical conclusion i can make in result of above discussion, in order to guide further discussion (or raher, lack of) for those (probably few) who would side with me on the matter. I hope you will not grudge.

Oh and that paper, ArcticMelt2, has one "Mark Z. Jacobson" as its lead author. Stanford professor alright. The guy advocates 100% wind + solar + hydro for US through his career, despite the fact it's impossible to do in practice in any observable future, as well known to any person who spent more than few days studying how power grids work. Further, when confronted about it, the guy filed a lawsuit demanding 10M USD in damages: "In 2017, Ken Caldeira and 20 other researchers published the largest focused critique of Jacobson's "100% Renewable world" paper.[68] David Victor of the University of California, San Diego, a co-author of the critique of Jacobson’s model for a cheap "100% renewable world", was motivated to contribute to the paper "when policy makers started using this [Jacobson] paper for scientific support," when it was "obviously incorrect".[69] This 2017 critique resulted in Jacobson filing a lawsuit against the peer-reviewed scientific journal the Proceedings of the National Academy of Sciences and Christopher Clack as the principal author of the paper, demanding $10 million in damages for defamation.[68] News reports and academics have criticized the lawsuit.[70][71][72][73] Jacobson withdrew the lawsuit in 2018 after re-evaluating the time and cost associated with potential appeals, stating that when he filed the lawsuit, he expected a settlement.[74]".

But sure, it's a scientific paper, it's a computer model, can't be wrong! Yeah. Sure. Matter solved. /s

I'm out of here.

[oren]

not answering my queries above despite my specific requests for you both to do so. This shows clearly i am dealing with nothing else, and nothing but, hypocrisy here

Sea ice volume is dropping, hence there can be no other explanation but flights sowing some chemical. Logical.
Queries not answered, hence there can be no other explanation but hypocrisy. Logical.
To be honest F.T., I think you are jumping to conclusions in both cases.

The issue of volume is a complex issue, and formulating a response to your query takes time, which I didn't have much of lately, dealing with the mayhem in the forum, and this being the weekend in which I am typically away from the computer and have less time for complex issues.
The response would have been along the lines of the "Slow Transition" theory. MYI was lost, partly due to export and partly due to melt. Now FYI grows every year, requiring the melting energy again and again, thus "now the MYI is melted the energy would attack the remaining volume" misses the cycle of winter and summer.
This is not a fully-formulated response, as that would take more time. But if you choose to "out of here", maybe I can save time on the full response...

[igs]

Note that the work was written several months before the catastrophic melting of 2012. It looks like no one really wants to stop the melting of the Arctic ice. Otherwise, commercial aircraft would now be flying around the Arctic ice. As it is written in the work, the costs of flying around the Arctic are hundreds of times less than investments in renewable energy. The public is more concerned with the depletion of fossil resources than with global warming. In this regard, governments welcome the melting of the Arctic ice as an incentive for the economic development of the Arctic.

That would increase overall fuel consumption and therefore worsen the impact of flying.

IMO it makes little sense to exchange local benefits for global worsening because after some time the benefit will be outweighed by the global conditions.

[interstitial]

<snip>
 The guy advocates 100% wind + solar + hydro for US through his career, despite the fact it's impossible to do in practice in any observable future, as well known to any person who spent more than few days studying how power grids work.
<snip>

More misinformation currently my PUD provides 97.41% carbon free energy most of the remainder is biomas.
Are you going to ignore this comment as well F.Tnioli? When will you provide me a well reasoned argument data and facts from credible sources to rebuff my counterclaims. I am asking you specifically F.Tnioli.

[blumenkraft]

Of course, a 100% renewable grid is technically possible.

Link >> http://publica.fraunhofer.de/dokumente/N-356523.html

(I had these stupid talks 20 years ago... Misinformation is never dying.    )

[kassy]

So there was this year with a big crash and then some recovery from that. So you ploy the yearly values and draw a line but that is not how that works.

If you look at a youtube movie of the ice over the years you can see it change to now where we only have a failing skeleton of bigger ice left. The trend will not keep reversing and hence you don´t need your theory.

I did not talk about "single year with a big crash". I talked about a trend, and about how that trend was reversed. Please note that "trend" means a number of years forming clear progression - like decline or increase. And that number can not be "1" or "2" or "3". It takes 5+ years to even start a trend.
...
Your inability (or worse, an act of intentional faked ignorance) to grasp even such most basic words - such as "trend" - makes me unwilling to comment your post in any further detail. Sorry. 

You drew 2013-2018 on a chart and plotted a line through that. Climate runs on 15 year trends to eliminate noise like natural variability. For arctic volume other things are at play because it is the old ice disappearing and lack of replenishment that will push the system over the edge. 

I am quite happy to debate this further after the 2020 data point has come but maybe that is useless if you look at the trend here:
http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2.1.png

2 years are near 2012 and the current one has plenty of time to go below.