1. Mick West

    Mick West Administrator Staff Member

    Last edited: Nov 20, 2013
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  2. Pete Tar

    Pete Tar Senior Member

    I was looking for pictures of aerodynamic contrails from gliders and found these pictures; however, I'm wondering if perhaps these are smoke generated for show?
    I was hoping to find a picture of an aerodynamic trail that persisted and spread from an engine-less aircraft, but I don't know if these would exist as gliders fly too low and slow to make that sort of persisting contrail?
    8532852833_ffcdb3f433_z.
    glider-aerobatics-david-gehman.
    Contrails-and-Smoke.
    flat,550x550,075,f.
     
  3. GregMc

    GregMc Senior Member

    The third one is rather informative, and shows clearly that when an artificial chemical is deliberately released from an aircraft such as the wingtip smoke flare on the glider, there is no clear air gap between the point of exit , ie, the nozzle and the trail. In contrast the contrail from the jet has a clear gap of almost half a fuselage length from the engine to the start of the trail because of the time it takes for the hot invisible water vapour from the exhaust to condense and freeze into ice crystals.
     
  4. Mick West

    Mick West Administrator Staff Member

    These are definitely smoke, here's the actual smoke generator from the third photo:

    http://www.planespotters.net/Aviation_Photos/photo.show?id=275818
    [​IMG]

    But "no gap" also happens with aerodynamic contrails. You can tell these are not aerodynamic contrails because they persist for too long.

    Aerodynamic contrail from an engineless aircraft (at least one with the engines switched off):

    [​IMG]

    Technically you probably could get an aerodynamic contrail from a glider. It's just rather unlikely. The high humidity required would probably be a factor, as gliders tend to fly only in nice weather, for obvious reasons.
     
    Last edited: Nov 20, 2013
  5. Pete Tar

    Pete Tar Senior Member

    Can an aerodynamic contrail persist and spread? That was what I was looking for. Any photos of experimental high-altitude gliders in action?
     
  6. Mick West

    Mick West Administrator Staff Member

    Only if it forms in an ice-supersaturate region. Most aerodynamic contrails form at relatively low altitudes, relative humidity with respect to water is below 100% so the trails are short-lived.

    The lift on a glider's wing might be too low to make much of a contrail, if at all.
     
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  7. Pete Tar

    Pete Tar Senior Member

    How about Felix Baumgartner?
    mqdefault.
     
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  8. JFDee

    JFDee Senior Member

    A sequence in this glossy documentary (" ... From Above" type) introduces a 'hail buster'.
    Good shots of the flare-like silver iodide dispenser. Narration in German.

    A stupid rule in Germany limits the availability of the online video to seven days (from yesterday). If someone should find it useful, creating a local copy may be advised.

    The sequence in question starts at 24:27

    http://www.zdf.de/ZDFmediathek/beit...n-oben-3-Land---in-HD%21?bc=sts;suc&flash=off
     
  9. Mick West

    Mick West Administrator Staff Member

    You should able to download it directly from: http://nrodl.zdf.de/none/zdf/13/05/130522_dvo3_landhd_tex_1596k_p13v9.mp4 518 MB though.

    Here's a 3 minute 30MB clip of the cloud seeding sequence:

    https://www.metabunk.org/files/Deutschland von oben 3 - Cloud Seeding clip.mov

    It shows nicely what cloud seeding looks like ... small plane in a cloud with no visible trails.

    [​IMG]
     
    Last edited: Nov 20, 2013
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  10. Leifer

    Leifer Senior Member

    Vädersolstavlan

    (Swedish for "The Sun Dog Painting")

    Artist Urban Målare, Jacob Elbfas
    Year 1535, 1636
    Type Oil-on-panel
    Dimensions 163 cm × 110 cm (64 in × 43 in)
    Location Storkyrkan, Stockholm
    [​IMG]

    Maybe the earliest depiction of an Atmospheric Halo, 22deg. halo, parhelic circle, with sun dogs.

    ...interesting quote from the top link:
    [​IMG]
    Credit: User: Ben-Zin on german wikipedia, there NOAA, original "Bild:Halo.jpg" in german wikipedia uploaded by (9. Okt 2002), reuploaded by de:Benutzer:Karl Bednarik (15. Feb 2004) after filename conflict
     
    Last edited by a moderator: Nov 20, 2013
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  11. Ross Marsden

    Ross Marsden Senior Member

    This phrase sticks out for me:
     
  12. Hama Neggs

    Hama Neggs Senior Member

    I don't know where to put this, and maybe it's old news for people here, but just look at this:

    http://globalskywatch.com/stories/my-chemtrail-story/index.html#.Ue8PdtK1GSp

    Look at the organization and work which has gone into this. I'm just amazed. It's mostly based on the notion that normal contrails are so rare that most people have never seen one, but it is greatly fleshed-out, with page after page of details and conspiracy stuff. No wonder people believe this stuff. Anybody ever deal directly with this guy? Move this post or just delete it, if it's not of interest.
     
  13. Mick West

    Mick West Administrator Staff Member

    Yeah, try a search here for Russ Tanner, he's come up before.
     
  14. Hama Neggs

    Hama Neggs Senior Member

    Yes, I see. I assume his story about professional airline pilots contacting him to thank him and stating that they have never seen a contrail come from a jet engine is just a flat-out lie.
     
  15. Steve Funk

    Steve Funk Active Member

  16. Jay Reynolds

    Jay Reynolds Senior Member

    Could just be people pulling the wool over his eyes, knowing he is gullible enough to accept anything which might confirm his previous beliefs.
     
  17. Ross Marsden

    Ross Marsden Senior Member

    (I'm assuming you are referring to Hamma Neggs' comment about Russ Tanner and his airline pilots story.)
    He talks about disinfo agents, pretending to be supporters of the fight who saying outrageous things to discredit him and his followers (such as his example of the caller asking for funding to shoot down, Dane's response to that, etc).
    These "airline pilots" could well be disinfo agents, actually supporters of the fight and possibly his own followers, phoning him pretending to be airline pilots. I suppose that is what you mean by "people pulling the wool over his eyes". I'm suggesting it's his own people, or at least chemtrail believers from the wider field.
     
  18. Tom Upton

    Tom Upton New Member

    this image is oddly very beautiful in its own way. Like the recent Hubble photographs of the celestial bodies. What a great way to see information!
    ~TEU

    [​IMG]

    Smaller:
    [​IMG][/quote]
     
    Last edited by a moderator: Nov 20, 2013
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  19. Ross Marsden

    Ross Marsden Senior Member

    The original is probably on this page: http://www.nasa.gov/multimedia/imagegallery/image_feature_2393.html

     
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  20. cloudspotter

    cloudspotter Senior Member

    This is pretty amazing to watch and a good video to show those bemoaning the lack of blue skies http://apod.nasa.gov/apod/ap130724.html

    As an afterthought - you can also see contrails and high level clouds preceding the bad weather. I could watch that all day.
     
    Last edited: Jul 26, 2013
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  21. TomC

    TomC Member

    Stumbled on these 2 stories on contrails from the daily mail. For those of you not from the UK, this is the tabloid that routinely prints sensationalist populist nonsense, blames everything on immigrants and the eu, thinks global warming is a hoax and gets outraged about porn but yet is creepily obsessed with women's bodies.

    Anyway, the 2 stories actually put across the basic science reasonably well, and contain some good pictures, although the second does whip up a little hysteria about the contrails blocking the sun

    http://www.dailymail.co.uk/sciencet...pture-commercial-jet-engine-trails-space.html
    http://www.dailymail.co.uk/sciencet...ttack-vapours--jet-trails-block-sunshine.html

    The best thing though is this diagram in the second article.
    [​IMG]

    Oh, and the comments, which are hilarious. Of course it is all a part of the big disinformation campaign...
     
    Last edited by a moderator: Nov 20, 2013
  22. Ross Marsden

    Ross Marsden Senior Member

    As I understand the contrail formation process, there are some problems with that diagram.
    It does not mention condensation.
    It points to small blue balls in two places and labels them as "water vapour" in one place and "water droplets" in another.
    Sulphates, Nitrates and soot (combustion products) play more of a role in the formation, especially the freezing, than the hydrocarbons (from incomplete combustion).
    It shows no gap at all between trails and the engine. The red shading, I suppose, is meant to represent high gas temperature; so what does the white represent?

    I suppose the problem is how to illustrate that the trail becomes visible (condensation) where the mixture of exhaust + environment reaches water saturation. Freezing of all the condensed vapour then follows aided by the sulphates, nitrates and soot, and possibly ice that froze just earlier, but I think the latter is a small player (I could be wrong). The resulting ice particles grow by the deposition of surplus vapour in the ice-supersaturated air of the environment to form the cirrus we eventually see. There are some schematics sketches that do show this in the literature.
     
  23. Mick West

    Mick West Administrator Staff Member

    Yeah, it's a rather confused diagram. Better than nothing I suppose. At least the end result is essentially correct. Jet engines make water, which makes clouds. It's a start.
     
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  24. MikeC

    MikeC Closed Account

    it mentions condensation in item 3 - "These crystals act as nuclei around which more water condenses...."
     
  25. Mick West

    Mick West Administrator Staff Member

    Which is wrong. As it accretes (turns from gas to solid). It condenses in step 2, where they say it freezes. Backwards.
     
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  26. Ross Marsden

    Ross Marsden Senior Member

    Yes, it has the process all wrong. "condensation" is there in completely the wrong place which is why I missed it!
     
  27. Hama Neggs

    Hama Neggs Senior Member

    This isn't a graphic, but I don't know where to post it. It's Rosalind Peterson admitting to having no proof of chemtrails. Enjoy. If this is old news, just delete it.

    QUOTE ROSALIND PETERSON: "In 10 years of research..... I have no proof whatsoever that the jets are releasing anything but jet fuel emissions."
     
    Last edited: Aug 7, 2013
  28. TomC

    TomC Member

    I think accretion is the process of super cooled water freezing on contact with an existing ice crystal, deposition is the phase change from gas to solid.

    I think the issue with the diagram is there are many processes going on in cloud physics, condense and freeze are the 2 that are probably best understood by the general public.

    From what I remember for persistent contrails, we essentially need an environment in which (after the addition of water vapor from the exhaust) the vapor pressure is greater than that for saturation with respect to water (i think if it is greater than that with respect to ice, but not water then a contrail will form, but will not be persistent).
    Then, there are quite a few physical processes going on...

    Water vapor condensing onto cloud condensation nuclei (of which there are many) to form super cooled water droplets.
    If the air is cooler than around -40c, super cooled water freezing spontaneously to form ice crystals (think this is where the -40 rule of thumb comes from).
    Ice crystals forming (and growing) through deposition of water vapor onto ice nuclei (much less common than regular condensation nuclei from what I remember)
    Ice crystals growing through accretion with liquid water.
    Ice crystals growing through aggregation (bumping into each other and sticking together)

    So I guess you could sum it up as..
    Water vapor condenses into water droplets
    Water droplets freeze to make ice crystals
    Ice crystals grow through deposition, accretion and aggregation.
    Ice crystals = clouds

    Water's a tricky substance... I remember when being taught met our lecturer commenting on how lucky we are that water can exist in all 3 phases at the temperatures found in the troposphere, and if it weren't for this we'd have no clouds or rain
     
  29. Mick West

    Mick West Administrator Staff Member

    Ah, I've been using accretion exchangeably with deposition. Darn, I've got a bit of editing to do.
     
  30. Ross Marsden

    Ross Marsden Senior Member

    I have a chart that I have screenshot in 3 different poses.

    Here they are:
    The axes are temperature (horizontal) and water vapour partial pressure (vertical).
    The static parts show the saturation vapour pressure with respect to ice, and the saturation vapour pressure with respect to water.
    The area below the ice line is unsaturated, and cloud won't form there; any cloud in this region will eventually dissipate.

    The area between the ice line and the water line is where the air is supersaturated with respect to ice, but unsaturated with respect to water.
    In the presence of ice, there is a surplus of water vapour and it will deposit on any ice present until the water vapour partial pressure decreases below the saturation pressure for ice. If there is supercooled liquid water in this region it will evaporate because this region is unsaturated with respect to water.

    Above the water line is saturated with respect to water, and will be in cloud - either of ice crystals or supercooled water droplets.

    For condensation or freezing to occur, there must be cloud condensation nuclei (CCN, for condensation) or freezing nuclei (FN, for freezing).
    There is an abundance of CCN in the atmosphere, so moist air brought above the blue line (by any process; cooling, mixing) will immediately and spontaneously condense to form a visible cloud.
    In the atmosphere there are very few FN, so air brought into the region between the ice and water line will not form an ice cloud unless some freezing nuclei turn up.

    The variable part of the charts is a line that represents the mixing of exhaust gasses (from way up to the top right, "off the chart"), and the environment (bottom, labelled).
    The Relative Humidity with respect to ice (RHw) and with respect to ice (RHi) is shown as a percentage.
    These are formed by the ratio between the water vapour pressure (WVP) of the environment and the saturation WVP with respect to water (blue), and the saturation WVP with respect to ice (cyan), respectively (vertical lines in red, blue and cyan).

    This first pose of this chart represents the jet exhaust gasses mixing with the environment and NOT forming a contrail.
    Even though the mixture is ice saturated for a while, it is never water saturated - it never crosses the water saturation line.
    TvVP_noContrail.


    The second pose represents the jet exhaust gasses mixing with the environment and forming an ephemeral contrail.
    The mixture condenses where the temperature is about -38°C (in this case). The droplets of supercooled water freeze by various processes, spontaneously if the temperature is below about -42°C, or seeded by soot, or sulphur dioxide in solution (H2SO4), nitrate, etc.
    Mixing continues out of the water saturation zone with no change since there is no water - it's all ice particles/crystals.
    Mixing continues (towards the environment condition) through the ice saturated zone, and out. Now the ice is in the unsaturated zone, and starts to evaporate, and so the contrail dissipates.
    TvVP_EphemeralContrail.

    The third pose of this chart represents the jet exhaust gasses mixing with the environment and forming an persistent contrail.
    The mixture condenses where the temperature is about -36°C (in this case). The droplets of supercooled water freeze by various processes, as in the pose above.
    Mixing continues out of the water saturation zone with no change since it's all ice particles/crystals.
    Mixing continues towards the environment condition which is in this case is in side the ice-supersaturated zone.
    Now the ice cannot evaporate - the air is already ice saturated. So the contrail persists, and the individual ice crystals grow in size by the deposition of the surplus water vapour directly onto the ice.
    TvVP_PersistentContrail.
     
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  31. Mick West

    Mick West Administrator Staff Member

    Last edited: Nov 20, 2013
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  32. TomC

    TomC Member

    Yes, aside from slip up with using "condense" in the wrong place I think the diagram from the mail does a really good job. It gives a basic description of what is going on in language that makes logical sense to people not familiar with contrails.

    Engines produce water, which is what clouds are made of.
     
    Last edited by a moderator: Nov 20, 2013
  33. Mick West

    Mick West Administrator Staff Member

    Then there's this classic explanation from 1943, essentially the same:
    [​IMG]
     
    Last edited: Nov 20, 2013
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  34. TomC

    TomC Member

    From 1943! That's brilliant!

    Incidentally, does anyone know where "normal contrails don't persist" idea originated?

    It is the bedrock of the Chemtrails theory and yet unlike almost all their other claims they never cite any "evidence" to support it.

    E.g. The Govt. is geo engineering because we found a patent.
    Contrails don't persist because..... ???

    At least with their other ideas there is some flawed logic behind them, but with the key one that underpins the whole theory and is often the first thing mentioned to people new to the conspiracy to get them to believe it, there is no logic behind it at all, no supporting argument whatsoever! (Well, aside from "I don't remember them doing that when I was younger").

    Unfortunately, it seems that when you point this out to people they are so far indoctrinated that they essentially believe all the scientific research that contradicts their theory has been fabricated by the government.

    If the govt was clever enough to create fake science saying contrails persist and destroy science saying they didn't, how come they forgot to cover up the patents on geo engineering and research into cloud seeding etc.??
     
    Last edited by a moderator: Nov 20, 2013
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  35. Mick West

    Mick West Administrator Staff Member

    I keep asking them that question. They don't ever have an answer. The most common thing is "your breath does not persist on a cold day"
     
  36. Ross Marsden

    Ross Marsden Senior Member

    Thanks.
    The charts I posted there have scaled axes, and the saturation vapor pressure lines have been calculated and are drawn correctly.
    In addition, I hope I have explained the difference between RHw and RHi, and how they are calculated.
     
  37. Ross Marsden

    Ross Marsden Senior Member

    But, actually, on a cold enough and humid enough day, it totally does!
     
  38. Mick West

    Mick West Administrator Staff Member

    Indeed it does. I discussed this with Dane, and he asked why (in Alaska) it does not leave a long trail behind you like a jet engine. I explained this is because people are a lot smaller than a jet engine, and a lot closer to the trail than a viewer 6 miles below. He seemed unconvinced.
     
  39. Ross Marsden

    Ross Marsden Senior Member

    The other (obvious) thing is that it doesn't happen every day, but on certain (ice fog) days, it does happen. It is most noticeable with vehicle exhausts.
     
  40. Mick West

    Mick West Administrator Staff Member

    Which I also told him.
     
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