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I wanted to know what the scientists had to say about the increased contrails (white lines in our sky that spread out, turning our blue skies white), so I researched, found the most amazing research, and wrote to the University of Utah Meteorology Department hoping to address this issue in our inversion/pollution prone area that is covered with contrails almost daily.

The NASA affiliated research I found proved the following:

1.  Contrails are increasing in numbers, doubling by 2015 and quadrupling by 2050 if nothing is done.

2.  Contrails do affect our weather

3.  A contrail-sensitive area can be predicted between 1-6 hours in advance

4.  Because contrails can be predicted, contrails can also be reduced and/or increased

Below the orange squiggly is the letter I sent to the U of Utah on February 25, 2013.  It was one of those days that started out with bright blue skies, not a cloud in sight until the contrails began and didn't stop until the sky turned white.  Here's a 2/25 noon pic of contrails above SLC valley

2:25:2013 SLC Contrails 2 12-45PM

Sadly, the links to a couple of the research papers I read no longer work.  This is the message that now appears:

The NASA technical reports server will be unavailable for public access
while the agency conducts a review of the site's content to ensure that it
does not contain technical information that is subject to U.S. export control laws
and regulations and that the appropriate reviews were performed.
The site will return to service when the review is complete.
We apologize for any inconvenience this may cause.
Granted, the research papers included long, complicated mathematical equations that could teach other countries about this science and I guess that is proprietory information?

Fortunately, before the articles were taken down by NASA, I did copy and paste the information written that substantiates the items listed above.

I will let you be the judge.

Here's the letter:

Good morning, Professor

I have been studying/tracking local contrails as a non-scientific observer for a couple of years and found research that verifies some of my conclusions.  I wanted to share both with you for your opinions.

I am writing today because of the high quantity of contrails I am observing this morning, with hopes that you might have a chance to observe them as well.

Of particular interest to me is what appears to be a trend.  Specifically, in front of a system the contrails seem to increase dramatically.  I understand the conglomerate of atmospheric conditions that might facilitate these.  However, as it is proven that heavy contrails can affect weather, I wonder if these are planned and, if not, if we might provide some input to the industry to plan flights in order to reduce them over our populated areas.

I found this research paper that clearly states that the altitude of flights can directly determine the creation of contrails.  The paper also states that creation of contrails will double between the years of 1992 and 2015 and quadruple by 2050.

Evaluation of Contrail Reduction Strategies Based on Aircraft Flight Distances

""This paper evaluates a set of contrail reduction strategies based on the flight range of aircraft as contrail reduction strategies have different impacts on aircraft depending on how they plan to fly...

The strategy for reducing the persistent contrail formation is to minimize the contrail frequency index by altering the aircraft’s cruising altitude....

The global mean contrail coverage in 1992 was estimated to double by 2015, and quadruple by 2050 due to predicted increase in air traffic.3

Studies suggest that the environmental impact from persistent contrails are estimated to range from three to four times, to ten times larger than from aviation-induced emissions. To address minimizing environmental impacts due to contrails, methods to reduce aircraft induced persistent contrails have been proposed.""

The paper concludes that contrails creation can be reduced by 75% by simply adjusting flight altitudes.
The percentages of the reductions are similar with different α values for long- distance flights. For the top three contrail days in April, 2010, the contrail frequency index per 1,000 miles for medium-range, long-range, and transcontinental flights can be reduced by an average of 75%.
The authors of the paper above have also written the following paper, which you CAN read.

A Linear Programming Approach to the Development of Contrail Reduction Strategies SatisfyingOperationally Feasible Constraints

A class of strategies has been proposed to reduce contrail formation in the United States airspace. A 3D grid based on weather data is built and the cruising altitude level of aircraft is adjusted to avoid the persistent contrail potential area with the consideration to fuel-efficiency.

Also, in this paper below, it states that the production of contrails can even be predicted ahead of time.  If so, isn't it possible that contrail production over the Wasatch Front can be reduced if meteorologists and the aviation industry could work in concert with each other.

Prediction and Use of Contrail Frequency Index for Contrail Reduction Strategies

"The objective of this paper is to derive a class of indices that can identify and predict, up to six hours in advance, regions of airspace with high potential for contrail formation.

""Traffic and weather forecasts were used to generate the predicted contrail frequency index. The indices are used to identify air traffic control centers and altitudes with high contrail formation activities over the next one to six hours."

V. Conclusions
This paper described a methodology to predict contrail frequency index for contrail reduction. A class of predicted indices that reflects the severity of airspace contrail formation frequency was derived. The indices consist of weather forecast and actual and historical air traffic data. The results show that the predicted indices are affected more by changing atmospheric conditions than by small daily variations of traffic. For the data tested, the one-hour predicted contrail index is highly correlated with the actual index, resulting in an average correlation coefficient of 0.85 and is lower with longer prediction time. The average correlation coefficient between the actual index and the two-hour, three-hour, and six-hour predicted index are 0.72, 0.64, and 0.52, respectively. In terms of developing strategies for contrail reduction, there is a 83.47% success rate to identify centers with contrail frequency index greater than a threshold, 69.24% using two-hour index, 58.31% using three-hour index, and 38.92% using six-hour index. The method of using predicted contrail frequency index for contrail reduction shows promise but requires detailed future evaluation in a fast-time traffic flow management simulation environment."

In this Prediction paper, Salt Lake is shown as one of seven areas that "need a reduction strategy"    Again, inversions in SLC create dangerously toxic air that is harming residents.

Contrails creation can be predicted 2

For implementing a contrail reduction strategy, the centers with high contrail frequency indices need to be identified. As an example, the contrail reduction strategy may be enabled when the centers have indices higher than 100. This would affect seven centers including Los Angeles Center (ZLA), Salt Lake City Center (ZLC), Albuquerque Center (ZAB), Dallas/Fort Worth Center (ZFW), Houston Center (ZHU), Jacksonville Center (ZJX), and Miami Center (ZMA). All of the one-hour, two-hour, and three-hour prediction indices are able to correctly identify the centers that need a reduction strategy with the exception that the three- hour predicted index fails to identify ZHU.
What is really interesting is the ability to very accurately predict when contrails will be created, from the Contrail Prediction paper cited above:

Contrails creation can be predicted accurately

The evidence indicates that a decrease in contrails is possible by simply adjusting the altitude of medium range flights, which my analysis* indicates are the flights creating our contrails.  

A few of the scientists that wrote the above papers agree with me.   Specifically, in this paper:

Aircraft Trajectory Optimization and Contrails Avoidance in the Presence of Winds

""There are indications that persistent contrails can lead to adverse climate change, although the complete effect on climate forcing is still uncertain.

A flight trajectory optimization algorithm with fuel and contrails models, which develops alternative flight paths, provides policy makers the necessary data to make tradeoffs between persistent contrails mitigation and aircraft fuel consumption.

This study develops an algorithm that calculates wind-optimal trajectories for cruising aircraft while avoiding the regions of airspace prone to persistent contrails formation."" (emphasis mine)

Lastly, I have watched a heavy day of contrails spread out and completely cover an AM blue sky by mid afternoon.  Admittedly, I lack a scientific background; however, I am curious about the effects this contrail sky cover might have on our inversion problem (Salt Lake/Utah counties have one of the highest particulate pollution problems in the country).

Based on the above research and the scientific clout of the U of U's meteorology professionals, is it possible that the airlines could be asked/required to, at the very least, adjust their flight patterns and/or altitudes to eliminate contrail creation when we are in the throes of our unhealthy air quality periods?

Thank you for your consideration and time addressing my questions.  

*My Tracking the Contrails technique using FlightAware website

I have been using FlightAware to find out what airline/plane is creating contrails in our area.  

Specifically, I open FlightAware in two screens which I put side by side on my iMac.

Both are opened to the SLC airport link. When I observe a heavy contrail, I go to FlightAware on the left screen, find the plane ID and enter it into the Flight Number box on my right screen.  The planes that create the contrails are always the green planes.  The torquiose planes are the flights arriving/departing from the SLC airport and fly low enough to avoid creating contrails.

Steps to observe and identify flights creating contrails for Salt Lake area (use your own airport for your area):

1.  Open FlightAware SLC.  Link

2.  Click on the 4 arrows to bring up larger view of KSLC air space activity.  This will bring up a large view.  Increase screen size to fill left half of computer screen

3.  Open new window.  Then open FlightAware SLC.  Link

4.  Move to right half of computer screen, making sure that the Flight/Tail# identification Box is visible

5.  When a contrail is observed, find the plane (again always green colored).  If the Flight/Tail# isn't displayed, hovering the cursor over the green plane will usually display the ID.  If that doesn't work, click on the plane.  This will create a view of just the specific plane's history.  You will then have to reopen KSLC for viewing entire airspace in the left hand screen.

6.  Enter the Flight/Tail# info into the Flight/Tail# box on the right screen Flight/Aware and observe the flight history, which includes altitude.

7.  I also use this webcam which often shows the contrails I track.  It would be very helpful if the archival records included recent items.
Salt Lake Valley Hazecam (Full Size Image at Bottom of Page) @

I have observed many days over the past couple of years.  

I have observed that many airlines create these heavy contrails; however, only when flying at the altitudes conducive to contrail creation, explained by the research above.

I have also observed that the flight paths of many of the contrail creators seem to illogically fly directly over our most polluted areas en route, literally going out of their way to do so.

Here's a good example. Airplane WJA1486.  This plane flight frequently, if not bi-daily, creates a contrail over our valley.  If you click on each day of WJA1486's flights beneath the map, you will see a consistent pattern of flying over our most polluted air spaces.

At 11:50 AM (February 25, 2013) this flight, WJA1486, created a heavy contrail.  It didn't have to fly over our area if a direct path had been chosen.  Why did it?

I also wonder if Utah's many cloud seeding, ground-based generators help set up the contrail conditions?  

See map of Utah's weather modification generator sites here:

Lastly, I wonder if the atmospheric conditions being created with contrails and intentional weather modification technology west of the Rockies could, in any way, contribute to setting up areas to the east of the Rockies for more intense weather events?  

I understand that much more measuring and detail recording would be required to make a case for asking airlines to be more considerate of our sensitive area; however, I believe the above is an easy technique to begin do so.  

I think it is possible, over time, to prove that these contrails do, in fact, impact our local weather and air pollution and, more importantly, can be avoided with the cooperation of the airlines.

I would like to volunteer to help if you see any merit in doing so to either help prevent some of our country's extreme weather events and/or help reduce Utah's horrible air pollution.

Again, thank you if you have read this far.  Today's whitening sky is definitely the result of heavy contrails.  Lastly, could these have an effect on The field campaign for the Persistent Cold-Air Pool Study?  


I didn't get a response, sadly.  And, hopefully the NASA affiliated research papers I found and read before writing to the U of U Professor will return so you, too, can read them in their entirely.


Contrails can be predicted and reduced by changing flight altitude and/or avoiding, when possible, areas conducive to contrail creation.  Conversely, contrails can predicted and increased if the atmosphere is conducive.

A heavy contrail presence, or lack thereof, can affect weather although online research provides conflicting outcomes.

From New Scientist

Contrails warm the world more than aviation emissions

From the Christian Science Monitor

Airplane contrails and their effect on temperatures

Here's a visual demonstration of contrails becoming cirrus clouds from NASA

NASA Satellite Spies Aircraft Contrails On the Move


For those wishing to do more research, the authors of the papers cited above are

Neil Y. Chen and Banavar Sridhar
NASA Ames Research Center, Moffett Field, CA 94035-1000


Hok K. Ng ‡ University of California, Santa Cruz, Moffett Field, CA 94035-1000

Another paper by the above authors:


Contrails create cirrus clouds.  Cirrus clouds affect weather.  This is for the scientists among us:  Cirrus Clouds have a great influence on weather. Scientific Paper


Do you see lots of contrails in your area?

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Comment Preferences

  •  Well dones. I think you're spot on. (6+ / 0-)

    And as someone directly impacted by the inversion and local weather, I want answers!

    Send it to Gephart!

    Mindfulness is the first necessity of sanity and survival and the first casualty of Consumer Culture.

    by Words In Action on Fri Mar 22, 2013 at 01:21:20 PM PDT

    •  Would you sent it to Gephart? Please... (2+ / 0-)
      Recommended by:
      Words In Action, RiveroftheWest

      So many of the planes I have tracked could have easily avoided our air space.

      It's difficult to be happy knowing so many suffer. We must unite.

      by War on Error on Fri Mar 22, 2013 at 01:28:07 PM PDT

      [ Parent ]

      •  I'll try it out. (2+ / 0-)
        Recommended by:
        War on Error, RiveroftheWest

        Mindfulness is the first necessity of sanity and survival and the first casualty of Consumer Culture.

        by Words In Action on Fri Mar 22, 2013 at 01:42:02 PM PDT

        [ Parent ]

        •  It is important to note that NONE of the planes (3+ / 0-)

          flying in and out of SLC create contrails, although the question arises:  How much do they contribute to pollution.

          The contrails are from planes flying over SLC en route.  I believe, based on our unhealthy air, that we have a right to ask them to divert when we are suffering from our toxic inversions.

          The cloud cover these planes create cannot be helpful in scientific ways beyond my ability to present.

          I was disappointed the U of U professor didn't respond, btw.

          It's difficult to be happy knowing so many suffer. We must unite.

          by War on Error on Fri Mar 22, 2013 at 01:54:16 PM PDT

          [ Parent ]

          •  There's no percentage (1+ / 0-)
            Recommended by:
            War on Error

            in taking the time it would require to respond to such a complex letter for a mere random member of the public.  He's busy writing grants and jetting to meetings.  And  honestly, responding to your letter would require as much effort as you put into it; it's quite involved and while I don't know the science here, it's likely that there are a lot of complexities you didn't pick up in your research that he would have to explain to you from scratch if he wanted to explain at all.  Which he doesn't, because you're a layman and 1) it does nothing to advance his reputation and 2) it's godawful difficult explaining technical matters to a layman, ESPECIALLY for someone who's been working in the field for thirty years and tends to think in jargon.

            Your best bet for getting academic response, attention, and explanation of the things you don't know (and don't know that you don't know) is to talk to a graduate student or postdoctoral fellow.  They are closer to the "uninitiated" level and can still function in the English language (although they might require alcohol as a solvent in order to do so).  If you can build up a good relationship with such a person, THEN they might introduce you to their patron professor.

  •  There should be an app for that! (1+ / 0-)
    Recommended by:
    War on Error

    Yes, contrails are temperature related so altitude changes could help greatly. And the altitude changes would probably often be rather small. Get on it, geeks.

    We're fools whether we dance or not, so we might as well dance.

    by PowWowPollock on Fri Mar 22, 2013 at 01:31:10 PM PDT

    •  I added a couple of charts. (0+ / 0-)

      The scientists have been able to predict when an area is highly conducive to creating contrails.  If this is the case, then I believe there is a case for toxic air Utah to ask the flyover planes to cease and desist when we are having our harmful inversions.  Your thoughts?

      It's difficult to be happy knowing so many suffer. We must unite.

      by War on Error on Fri Mar 22, 2013 at 01:56:27 PM PDT

      [ Parent ]

      •  There is no basis in air pollution control (2+ / 0-)
        Recommended by:
        War on Error, mbayrob

        for saying or claiming that aircraft condensation trails have any effect at all on photochemical oxidant and PM 2.5 atmospheric transport and formation for regional, ground level ozone problems......either in Utah or anywhere else.

        The most serious environmental problems posed by aviation are:

        1.   Greenhouse gas emissions

        2.   Adverse effects on stratospheric ozone

        3.    Local airport area NOX emissions from takeoffs and landings

        •  In my area, contrails create a cirrus cloud (1+ / 0-)
          Recommended by:

          cover.  Literally, the sky goes from bright blue to white by the end of the day.  The contrails continue through the night, and we often awake to a white sky with no discernable clouds.

          My question is:

          What effect(s) do a dense cirrus cloud cover have on the ability for an inversion to lift?

          I know there are many variables comprised to create the inversion.  I would like to find some scientific data on the effects of plane-made cirrus clouds on inversion creation and/or maintenance.

          Thank you for commenting.

          It's difficult to be happy knowing so many suffer. We must unite.

          by War on Error on Fri Mar 22, 2013 at 04:24:18 PM PDT

          [ Parent ]

          •  You said: (0+ / 0-)
            "I would like to find some scientific data on the effects of plane-made cirrus clouds on inversion creation and/or maintenance."
            Formation of temperature inversions is a ground-based phenomena related to net infrared transfer effects on the atmosphere from the ground up.  There isn't any connection at all to aviation condensation trails at 35,000 feet....none.
            •  TY for forcing me to dig deeper (0+ / 0-)

              Forget the airplanes once a heavy, long-lasting cirrus cloud cover is produced, which happens frequently here regardless of the month.

              Inversions are mostly winter events because of the set up, as you stated

              cold air
              warm air (inversion layer)
              cold air

              It is possible that the plane-made cirrus cover could exacerbate the inversion because of the nature of the heavy cirrus cover.

              This paper addresses this

              Radiation Parameterization for Three-Dimensional Inhomogeneous Cirrus Clouds: Application to Climate Models

              I appreciate your patience.  Perhaps if you can provide scientific reports stating that cirrus clouds have no effects on inversion, I could be persuaded.

              My thinking is

              Cirrus clouds radiate solar heat and can help create and/or perpetuate the inversion layer.

              Planes are creating a cirrus cloud cover with their contrails.

              Planes contrails can exacerbate an inversion.

              Contrail creation can be predicted.

              Planes can avoid creating contrails over areas that are already experiencing an inversion.

              Contrail reduction was recommended for SLC by the reseachers above, in the diary.  See chart

              Also, this research paper is a wealth of information

              On the Transition of Contrails into Cirrus Clouds

              It's difficult to be happy knowing so many suffer. We must unite.

              by War on Error on Fri Mar 22, 2013 at 06:25:16 PM PDT

              [ Parent ]

              •  I'd actually encourage you to stop (0+ / 0-)

                because what you're doing is trying to create a conflation that has nothing to do at all with how the atmosphere works, what a temperature inversion is physically and why they form.   In doing so, you're engaging in a form of anti-science conduct, which is why I suggest you stop.

  •  Time for 5000 mph trains. (3+ / 0-)
    Recommended by:
    War on Error, Miss Jones, Jim P

    ... running in a tube under vacuum.

    It's actually quite serious : Vactrain.

    I deal in facts. My friends are few but fast.

    by Farugia on Fri Mar 22, 2013 at 01:39:21 PM PDT

  •  The NASA tech server being down is a (12+ / 0-)

    big damn deal.  Thanks very much, Rep. Frank Wolf (R-VA).  From Secrecy News yesterday:

    NASA Watch and The Unwanted Blog linked the move to a statement from Rep. Frank Wolf on Monday concerning alleged security violations at NASA Langley Research Center.

    “NASA should immediately take down all publicly available technical data sources until all documents that have not been subjected to export control review have received such a review and all controlled documents are removed from the system,” Rep. Wolf said.

    In other words, all NASA technical documents, no matter how voluminous and valuable they are, should cease to be publicly available in order to prevent the continued disclosure of any restricted documents, no matter how limited or insignificant they may be.

    The body of knowledge pulled from public access is so large, one policy analyst predicts it will never go back online because NASA won't be able to get the resources needed to review it all.

    More on it from SpaceRef.

    Worth a diary, WoE, if you have the time.

    "Injustice wears ever the same harsh face wherever it shows itself." - Ralph Ellison

    by KateCrashes on Fri Mar 22, 2013 at 01:51:51 PM PDT

  •  One thing that bugs me about them (2+ / 0-)
    Recommended by:
    War on Error, lenzy1000

    is when the military jets flying high (on practice flights, I guess) make deliberate x's in the sky. They seem to be the ones making the most contrails over my urban area - almost everyday. It is obviously done on purpose and done over and over again.

    It is visual pollution of the beautiful blue sky, if nothing else.

    It also reminds me how much money we waste on the military and so-called defense.

    •  My favorite as a giant capital "A" over SLCity (3+ / 0-)

      Very artsy.

      Is it the military?

      Try using the FlightAware app mentioned above, with instructions on how to find out who is coloring your blue sky white.

      Also, because the weather people etc are not acknowledging the role contrails are having on our sky cover, there are a lot of people quite convinced we are being poisoned.  "Chemtrails" are a huge issue online.  A simple inclusion in the nightly news report like "Well, those darn planes turned our sky white again today" could help people feel less frightened perhaps.

      It's difficult to be happy knowing so many suffer. We must unite.

      by War on Error on Fri Mar 22, 2013 at 02:21:39 PM PDT

      [ Parent ]

    •  Um, (1+ / 0-)
      Recommended by:

      do you really think they are deliberately making 'x's' in the sky to upset you?  And deliberately and purposefully doing it over and over again?


      "We will never have the elite, smart people on our side."~Little Ricky Santorum

      by Dahankster on Fri Mar 22, 2013 at 02:21:47 PM PDT

      [ Parent ]

      •  Actually, until the contrail issue is addressed (2+ / 0-)
        Recommended by:
        David Futurama, Farugia

        more broadly, people are left to their own conclusions.

        Check the last link in the diary, the NASA link.  Apparently "X"s are not so unusual as you will see in NASA's satellite pic.

        Of course David doesn't take contrails in his area personally any more than the citizens of SLC took the giant A over their city.

        : ))

        It's difficult to be happy knowing so many suffer. We must unite.

        by War on Error on Fri Mar 22, 2013 at 02:25:54 PM PDT

        [ Parent ]

        •  The contrails might be an issue... (1+ / 0-)
          Recommended by:
          War on Error

          but I feel that they might be not a significant cause of anything, at least in how you've laid it out in this diary.

          That 'A' that you happened to see over SLC happens to be a navigational point that is on the ground that aircraft use for navigation.  You can think of it as a junction if you like, but that is the reason why those contrails join at that point.  Even with the use of GPS, aircraft still use points in space and navigate by them.

          I have flown fighter aircraft and one of the things that I wanted to know was what the 'marking' layer was.  That marking layer was the altitude where I would provide a contrail and could easily be seen well over 30 miles away.  I want at all times to stay out of that altitude.  In a clear sky a visual on the bad guy is worth a thousand radar sweeps.  Therefore, I want to stay out of the contrails.

          The airlines are trying to get the most altitude and use the least fuel and are in the contrails all the time.  There are many reasons, but the contrail (or marking) layer go up and down everyday and depends on the composition of the atmosphere.  Typically, it is well above 30,000 feet.  The airlines fly between 29-45K', right in the prime area to create contrails.

          BTW, those 'A's turn into 'X's if the aircraft fly diverging vectors.

          "We will never have the elite, smart people on our side."~Little Ricky Santorum

          by Dahankster on Fri Mar 22, 2013 at 02:44:38 PM PDT

          [ Parent ]

          •  Great comment. (0+ / 0-)

            I have observed what you state.

            However,  if the cover created by so many contrails over our area are contributing to prolonged and harmful inversions, they the airlines can find a way to stop covering the populated areas of Utah when our inversions are happening.

            I was pleased to find research backing up the ability to spare us.

            The "marking" is interesting.  Again, why would they mark a populated area?

            It's difficult to be happy knowing so many suffer. We must unite.

            by War on Error on Fri Mar 22, 2013 at 02:49:43 PM PDT

            [ Parent ]

            •  Here's the thing... (1+ / 0-)
              Recommended by:
              War on Error

              we know what the marking layer is.  Only the fighter aircraft really care what it is.  We stay out of it in our training areas.  

              The airlines really don't care about that layer and fly over populated areas all the time.  If the airlines could fly at a lower altitude, use less fuel and make more money, they would do it.

              I have done both (airline and military) and SLC is a normal pathway into southern California, that is why you see so many contrails there.  The military aircraft at Hill aren't normally producing them.

              "We will never have the elite, smart people on our side."~Little Ricky Santorum

              by Dahankster on Fri Mar 22, 2013 at 03:06:04 PM PDT

              [ Parent ]

      •  asdf (3+ / 0-)

        I didn't say they are doing it to "upset me". Learn to read.

        I said they are doing it deliberately and that it bugs me.

        I'm sure they don't care what I think, nor what anybody on the ground thinks. It is probably just part of their training and flight hours.

        Ruins a perfectly good sky. The weather and pollution implications, I'm not sure of, but the diarist makes some interesting points.

        •  asdf x2 (0+ / 0-)

          You assumed that it was the military, also assumed it was deliberately.  You also said that they are doing this over an urban area.  

          All of those are most likely wrong assumptions as I explain upthread.

          I am with you on weather pollution. However you make assumptions that you haven't proven and I can guarantee making contrails in the sky are not a part of any training program.  

          Thanks for making sure I can read.  Reading is fundamental.

          "We will never have the elite, smart people on our side."~Little Ricky Santorum

          by Dahankster on Fri Mar 22, 2013 at 02:59:49 PM PDT

          [ Parent ]

          •  asdf (0+ / 0-)

            Well, I have seen what I have seen with my own eyes.

            You can think I am lying or mistaken.

            I have seen fighter jets flying way over the commercial traffic. The commercial traffic flies fairly low during the day over my house because they are headed to a nearby airport.

            Flying nearly straight up making a contrail and going back within minutes and crossing that contrail. Usually there are two jets in the sky when this happens and it used to be mostly on weekends, leading me to think it was Guard folks keeping up their hours.

            I have seen this too many times to count. My vision is 20/15. I known what I've seen. They deliberately make an X. I don't know why. I don't much care why, but they do it. And it is ugly.

            As far as your guarantees, ain't worth much to me. I know what I have seen. No one guys knows everything the Air Force, National Guard, and Navy do all around the world and all their flight training methods.

            •  Wow... (0+ / 0-)

              you have 20/15 vision?  Kewl!

              You still don't know what you are talking about. I guess the only commercial traffic you see is headed to the airport that is nearby.  Uh huh.  Have you ever been on an airplane? You know they do fly to other places and flew from other places, right?  

              Listen, I have been a professional doing this for over a quarter of a century.  I am not trying to fool anybody here.  You can believe me, or you can keep guessing as to what the hell is happening.  Ya know, since I guess Guard folks are going straight up making contrails (no they aren't!)

              You don't have to take my guarantee.  I don't know everything, but you have shown me you don't know much in this arena.

              I never said you were lying, but you are mistaken.

              "We will never have the elite, smart people on our side."~Little Ricky Santorum

              by Dahankster on Fri Mar 22, 2013 at 06:37:26 PM PDT

              [ Parent ]

    •  I have them making u-turns near my home (3+ / 0-)

      To the left of this picture(east) there is an airport 50 miles away. There aren't any airports within within 100 miles to the right of this picture(west). I observed one that stopped producing a contrail in the skies above only to return one hour later and continue where he left off. The amount of activity has also changed. When Bush was president it was an everyday occurance now it only seems to happen when we have above normal temps.

      Some people have short memories

      by lenzy1000 on Fri Mar 22, 2013 at 05:12:14 PM PDT

      [ Parent ]

  •  Interesting diary with very good questions (5+ / 0-)

    I recall how much science came out of the lack of contrails in the days after 9/11, fascinating and alarming stuff.

    I see contrails over my skies (north coast California) more often than not, but we're not a polluted area like SLC.

    Fry, don't be a hero! It's not covered by our health plan!

    by elfling on Fri Mar 22, 2013 at 02:21:46 PM PDT

  •  Thanks, I now have an answer to my conspiracy (2+ / 0-)
    Recommended by:
    War on Error, RiveroftheWest

    theorist lover. In my gut I knew this chem-trails stuff was nonsense, I just didn't understand the science of contrails well enough to rebut him, and usually found myself just nodding along to appease him.

    •  You can also print out the instructions (1+ / 0-)
      Recommended by:

      on how to use FlightAware to find out what airlines/planes are making the contrails over your friend's sky.

      Often, there is some modicum of reality within a CT theory; however, the Chemtrail story is frightening people and needs to be addressed more openly imo, especially as it is predicted that more and more contrails will be appearing over time.

      And information hole can easily become a conspiracy theory.

      It's difficult to be happy knowing so many suffer. We must unite.

      by War on Error on Fri Mar 22, 2013 at 03:12:49 PM PDT

      [ Parent ]

  •  I wonder (1+ / 0-)
    Recommended by:
    War on Error

    If increased contrails would help to offset global warming.


    And not a single word in the entire diary about "chemtrails".  My tinfoil hat is upset.

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