Friday, September 16, 2011

Why are there so many contrails today?

Driving in to work this morning, I noticed there were an awful lot of contrails in the sky. Why, I wondered, were there so many today?

[Holy contrails, Batman!]

Is it because it's a cold day today? Perhaps because we just had a front come through? To find out, I gave my old meteorology professor from Embry-Riddle Aeronautical University a call.

My guess is that you have a lot of moisture in the air there right now, Dr. Randell Barry said. Really? That's it? It's all because of water vapor? I'll explain it to you how he explained it to me. From the beginning...

Contrails (or "Cirrus aviaticus" if you're feeling snooty) are the long, skinny clouds that form behind airplanes. As with any other cloud, they need condensation and a little dust to form. Luckily for them, passing airplanes provide both. All the air has to do is be full of moisture.

Air can only hold so much water vapor - water in its gaseous form - before the water condenses, turning into a liquid. As air cools, the amount of water vapor it can hold decreases. Once air cools to a certain point - called the dew point - the air is saturated: It is full of water. That's when condensation happens. Clouds form in saturated air when water vapor attaches to fine particles like dust, salt or ice (formally known as "condensation nuclei") and condenses.

As long as the air temperature is close to the dew point, we know the air is full of water vapor and close to being saturated. At airplane cruising altitude, this air is ripe for contrail formation. The plane does the rest of the work.

Airplane exhaust contains both water vapor and some fine particles, Dr. Barry explained. When added to the surrounding moist air, the water vapor is enough to saturate the air, allowing the water vapor to condense on the small particles. And voila: Just like that, a cloud is born!

To prove his point, we pulled up an image of the United States taken by a weather satellite. On a water vapor image, bright white areas indicate moist air while dark gray areas indicate dry air. Sure enough, sitting over the eastern half of the U.S. was a huge area of moist air.

[This water vapor image, taken by a GOES weather satellite, shows an area of moist air covering the eastern half of the United States.]

To get 3D perspective, we then consulted a sounding - a chart that shows the data taken by a weather balloon. In the sounding below taken from the Dulles Airport area in Virginia, the temperature is represented by a black line while the dew point is shown as an orange line.

Right around 26,000 feet, the two lines approach one another, telling us that the air temperature and the dew point temperature there were close. The air at that height was full of water vapor. The two lines stay near one another all the way to the top of the sounding, so we can expect that airplanes flying at just about any cruising altitude in the Dulles area would find perfect conditions for contrail-making.

[This sounding taken from the University of Wyoming website shows the temperatures and dew points recorded by a weather balloon as it rose above Dulles Airport.]

That's all there is to it, then. As long as the air and dew point temperatures are close in the region where airplanes fly, contrails are likely. If the air is moist enough, the contrails may linger for a while. Otherwise, they may vanish almost as soon as they came. This morning, though, they lingered.

42 comments:

  1. It's because the jets are releasing particals of aluminum and barium into the atmosphere. The records are there for the reading in the archives of congress. Plus there is no fewer than 80 law-suits going on right now to try and stop spraying. I thought this was common knowledge.

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    1. What kind of aluminum and barium?

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    2. I was a kid in the 60's and 70's and I remember distinctly that the sky was on a clear day super blue and the low cumulus clouds were amazing to look at against the clear jet blue sky. And no, there were not a lot of contrails in the sky. I should know, I lived by an airport with jets flying by all day long. Going forward today, the sky is a milky mess of chemtrial clouds dispersed along with HARP formed clouds. Weather modification is a fact by the Government, and military whistle blowers abound with information about what is going on. I am a true believer of chemtrails. The sky is not the sky of my childhood. The rain patterns have definitely changed where I live. We don't get rain storms that would last for days. Rain is forecast but cloud patterns are always broken up when it arrives. Rain is spotty at best and last for maybe short bursts. I remember warm fronts of rain would sometimes last for a week on end, not anymore.

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    3. Spot on Mr Way, same here.
      Would often lie in a field watching aircraft in my younger days, trails dissipated in a few aircraft lengths and left NOTHING!
      These people are trying to get us used to the idea that they are spraying nano particulates into the atmosphere, up to no good in my view

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    4. This thread explains why we have an anti-science, orange criminal buffoon in the White House. Anti-intellectualism is destroying a once-proud nation. Too many people won't accept reality any longer. They want to believe in drama and conspiracy and it will be the eventual end of our country if we don't figure out a way to once again educate people effectively.

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    5. then tell the government to stop all the lies and furthering technologies to harm our planet and human and animal life.

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  2. in the eighties when i was a kid we never saw contrails ... airliners could afford to waste the fuel. remember this, contrails are made by applying flaps thus condensing the air ,causing a vapor cloud in the vacuum zone. what we are seeing in our skys are not harmless contrails.

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    1. Aircraft do not and never have used flaps at cruse altitudes. Flaps are used to slow the aircraft for landing and crate more lift for take off.

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    2. You never looked up. I was a kid in the 60s and 70s and remember seeing persistent contrails. One can find pictures of persistent contrails going back some 70 years. http://metabunk.org/threads/pre-1995-persistent-contrail-archive.487/

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    3. Exactly, you could take the pictures of a bomber raids in WOII as an example. They left the sky filled with contrails after they passed by.

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    4. The sky used to be clear, I have hundreds of photos taken across the USA since the 1950's. I moved to the S.W. 23 years ago & the "persistent contrails" (chemtrails) only became an every day occurrence about 10-12 years ago. I live in Az. and we hardly ever have clear, blue skies anymore. Wake up.

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    5. Yeah, think about how many planes were flying around 23 years ago dude. Even 12 years ago there would have been far less. Not to mention all those budget airlines popping up left right and centre now with cheap airfares. You're genuinely surprised as to why you're seeing more contrails than in the 1950s? You conspiracy theorists are more stupid than I thought, theres anywhere upwards of 70-80,000 flights world wide each DAY now, half of which are flying over the USA. Get a grip buddy, or a tin foil hat.....

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    6. Thank you I don't know how people can't just make a simple observation, why would they start appearing more and more over the years? I guess our air has more moisture now. I'm only 18 and I can just think back and realize that it was not happening this much to where I notice it and if I saw them this much as a kid I sure as hell would've been curious! I love nature and love to observe things like clouds and everything in general but I've only in the last few years started to notice more and more being present. It's like everyone has just been staring at the ground. And about that "more flights" claim, how about just 3 years ago? I was not seeing this many at that time and I lived in an area right next to a river, just in the last couple years I have seen more and more and more, get a grip.

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  3. with the power of the internet it should be quite easy to verify the hypothesis that there may be added particulate to air plane exhaust given the above explanation. People looking at trails in a certain area would be able to look up the GEOS data to see if they were in fact in a dry or wet zone for a given period and then relate the dissipation of contrails as fast or slow over a given period. Not an exacting qualitative study, but more of a qualitative does this make sense thing.

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  4. I have to agree with other anonomous posters that while I appreciate that WDBJ7 attempted to explain contrails, I don't think these are contrails at all. These tasted and smelled like hairspray mixed with bugspray yesterday, and they were OUT of normal flight patterns. WDBJ7, PLEASE INVESTIGATE WHY THERE WERE SO MANY PLANES OUT TO LEAVES THESE YESTERDAY PLEASE. Maybe they are 'just' vapor trails...however, my question is WHY WERE THERE SO MANY PLANES ON A WEDNESDAY MORNING to begin with...what were they doing out of their flight patterns.....and why the bad taste and smell associated with them please? Please do investigate this.

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    1. Thank you for asking questions being concerned about the way the sky looks today it's off the scale ridiculous contrails used to dissipate behind the jet they didn't linger and turn into clouds

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    2. The weather is being manipulated all you have to do is pay attention look up sky looks like crap most of the time with a bunch of streaks from Jets and the focus seems to be the sun blocking it solar radiation Plan B perhaps the Solar Shield courtesy of John holdren

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  5. I'm a diff anonymous guy, but i've looked into this as a layperson. contrails form occasionally behind planes under certain atmospheric conditions, but those dissipate relatively quickly. they do not spread out and form clouds as in the above pics. the aluminum barium thing, from what i've looked into, is a bit hysterical and based on a questionable lab analysis of a ground sample allegedly taken after 'spray filaments' fell to the ground after a spraying, but i still have to research that more. my memory of the report is that levels weren't any higher than normal levels... b

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    1. Thank you. Finnally a person not claiming endless conspiracies but who still notices there is something wrong with our present so called contrails.
      I, like many commenters here are also a nature lover. Particularly blue skies with well defined clouds and great sunsets in the evening.
      In the sixties as a young kid I traveled a lot (Germany to the US then to Peru then to England ). I also took a summer vacation with my mom to a few European countries .
      In 1970 I finally came back to the US. I NEVER SAW ANY PERSISTANT CONTRAILS EVER back then.
      I find it rather strange how so many people worship science today so much so that they will believe science even if science challenges their own perception.
      These people if science told them to jump off a bridge and told them they could fly and gave them a nice mathematical formula to prove it they would have no hesitation to jump.
      Besides that no one realized that there are two sciences. Theoretical and applied or technology. Funny thing though. technology never challenges my observations.
      Now to be clear. I loved to fly. And every time I flew I managed to get a window seat. I never saw thick white flumes coming out of the engines. HOWEVER I did see EVERY TIME a thin vapor trail coming off the end of the WING at CRUISING ALTITUDE.
      Also scientists (technologists ) specifically state that contrails only occur at altitudes above 25,000 ft where temperatures are about -50 F.
      I see them flying above so clearly that I know they are flying at about 5,000 ft and a huge flume of white mist comes out the back. When I lived in Peru I lived at 10,000 ft in the Andy mountains. It never got -50 degrees.
      I am no conspiracy theorist but no one really wants to tell the truth.
      However I now live on Long Island NY and there are VERY FEW persistent or even large flumes of white clouds. Yes there are some but we get days when there are non. The rest of the time a few in a day. So I am lucky and still see a fairly clean sky. Still quite blue.

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  6. 1. Barium and the other substances said to be present in "chemtrails" are pretty darned expensive to be spraying around willy-nilly.
    2. Thousands of people work in aircraft construction and maintenance. Hundreds of old planes sit in aircraft 'graveyards' across the US. And yet, nobody has ever found any physical apparatus on any plane (except crop dusters) suitable for emitting sprays.

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  7. I'm thinking that contrails are normal but would provide a great opportunity for scientists to "seed" to reduce global warming. Additional condensation nuclei (Aluminum etc. nanoparticles) could be secretly added to jet fuel at the refinery and few people would know. Since no whistle blowers have come forward with proof of this, it probably isn;t hasppening. Good idea though if global warming gets out of hand.

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    1. they are green housing us with questionable chemicals and you feel this~ is an appropriate reaction to global warming ... hello~!?!This is quite possibly contributing factor escalating the "green house effect" if it reflect's the sun fine but if everyone is more subject to alsheimers syndrome and aluminum poising is there perhaps a better agent or solution than flying night and day and poising the land and see with harsh chemical saturation's... think about it~

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    2. If you want to ruin a jet engine, add small aluminum particles to its fuel...

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    3. What no one seems to be able answer is why there will suddenly be 10 or 15 "contrails" in the sky criss-crossing each other all at once. Are there that many planes all flying over the same area of the country at once? That's the part that seems suspicious.

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    4. Well if conditions are right for contrails to persist longer than a few minutes you get lots of contrails crisscrossing the sky. There are about 80,000 flights/day in the US with 1/3 of them commercial flights that will at some point be at high altitude where contrails typically form.

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  8. If the link below doesn't help you understand why there are so many contrails these days, you really are ignoring reality. How could there NOT be tons of contrails with all these planes in the air? Website showing all the planes CURRENTLY in the air over the US: https://flightaware.com/live/

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  9. I'm real Anon Fam. Any time a "conspiracy" is born just keep digging, feds create theories to throw us off the scent, air travel exploded, if you live under a flight path, you're being doused with a watery jet fuel oil slick, the kind you see in ports with tankers going in & out all day, they don't want people complaining in their billions and undermining the urban airport industry now do they so "Chemtrails" is born, anyone pointing at clouds is now a conspiracy nut to be mocked.

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  10. i forget the exact year but in mid 80's or early 90's there was a world Olympics held in japan, china, korea? one of those east asian countries that the US government with that countries assistance did infact spew chemicals throughout the region in order to attempt to control the weather for that years olympics
    It has been going on for year and as more people pull their faces out of their useless cell phones and look up at the world, the evidence is unignorable.

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    1. Got a reference for more info, by any chance?

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    2. That was the 2008 Summer Olympics, China actually said they would keep the weather nice the whole time. After about 11 days during the race-walk competition it started pouring rain, it was hilarious. I like to think they did that on purpose.

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  11. I would say the government might be complicit in certain practices but blaming the “GOVERNMENT” (caps intended) is shooting yourself...a voter in a democracy...in the foot. YOU are the government...start to own it and stop blaming and get big corporations out of the government pocket. People talk about how bureaucratic and inefficient government is...big businesses are just as inefficient the bigger they get. Put your effort and anger in the right place. Run for a local office...serve and realize how easy governing is...NOT. Nothing and no one is all bad...many things are mostly bad (Hitler, etc) but they don’t get that way on their own...people help them directly or inadvertently...even by their opposition sometimes. The best we can do is try to understand what we distrust and dislike and change it if we discover it really is what we thought it was.

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    1. there is no true democracy. or true way of government at all. this life is a mere simulation of 3-d paralleled universe. coincidence does not exist. the common people (un-knowledged) citizens of earth are all controlled by powers unknown. just know that this game were in right now goes way past what any of us can truly understand...for that part of history hasnt revealed its face yet. or rather they have not shown us.

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  12. Simply put, The local scheduled air traffic averages about 50 daily flights (arrivals and departures listed at TLH). There are frequently more than a dozen criss-crossing "contrails" visible at one given moment in Tallahassee (geographically isolated far from any other air traffic). I call bullshyte (numbers don't lie, but the DOD accounting has to the tune of 15 trillion in the last 15 yrs)

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  13. Over Long Island especially on a beautiful day or right after a storm we get tons of criss crossing trails across our sky.
    I often wonder if this is why we are getting snow into the good part of spring? Also last snow we had some of it had a blue look to it? hmmmmmm?

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    1. What part of Long Island do you live in ? I live on the north shore and I get days where I never see persistent contrails. On the worst days only like one or two days in a week you see a few but never kris cross. I find most days are very beautiful. Long Island has some of the bluest skies I have seen in a long time.

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  14. There's no doubt NASA engineering the weather they're worried about all the other countries trying to do the same thing and of course the United States has to be number one just like making the first nuclear bomb

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  15. I grew up in the 1970's and 1980's Sydney, Australia, and never saw a contrail until, I moved to the United Kingdom in the 1990's. As Sydney had a much warmer air temperature than Glasgow, and the fact almost all planes landed in Sydney, there were very few high altitude flights to be seen, and so I guessed contrails only happened at higher altitudes. I look up now, in Prestwick airspace on the west coast of Scotland, and the sky is covered in parallel contrails heading trans-Atlantic.

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  16. May14-17-none (4days)
    May18-CHEMTRAILS (1day)
    May19-22-none (4days)
    May23-CHEMTRAILS (1day)
    May24-28-none (5days)
    May29-30CHEMTRAILS (2days)
    May31-June3-none (4days)
    June4-5-CHEMTRAILS (2days)
    June6-9-none (4days)
    June10-CHEMTRAILS (1day)
    June11-13-none (3days)
    June14-15-CHEMTRAILS(2days)
    June16-July4-none (18days)
    18 DAYS - NOT 1 CHEMTRAIL!!!
    July5-10-CHEMTRAILS (6days)
    July11-15-none (5days)
    July16-17-CHEMTRAILS (2days)
    July18-20-none (3days)
    July21-CHEMTRAILS (1day)
    July-22-27-none (5days)
    July-28-CHEMTRAILS (1day)
    July-29-Aug-14-none (17days)
    17 DAYS NOT 1 CHEMTRAIL!!!
    August-15-CHEMTRAILS (1day) August16-19-none (4days)
    August-20-CHEMTRAILS (1day)
    August-21-23-none (3days)
    August-24-CHEMTRAILS (1day)
    August-25-27-none (3days)
    Aug-28-29-CHEMTRAILS(2days)
    Aug-30-Sep-25-none(27days)!!!!
    27 DAYS NOT 1 CHEMTRAIL DAY
    Aug-26-27-CHEMTRAILS(2days)

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  17. There were never as many trails in the sky years ago I have many pictures and you don't see anything in the sky except for bright blue and not leaving a trail now everyday I go outside the sky is littered with these trails and they're getting bigger and more frequent as the years go by

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