Contrails and Weather, Hernando Island

OK, fair observation.

The condition for contrails to persist is called ice-supersaturated. This means that the relative humidity is so high that the air temperature is below the frost point temperature.

In the situation where the RH is so high that the air temperature is approaching the dew point temperature, forecasters would be predicting cloudy or overcast. This is because there are plenty of cloud condensation nuclei (CCN) in the air for the water vapor to condense on, so liquid water cloud formation can occur quite readily. In the case of cirrus cloud (high cloud), the droplets freeze more or less spontaneously because the temperature is below the homogeneous nucleation temperature - about -42°C. (This is not to be confused with the temperature often quoted in connection with contrail formation.)

Back to the condition of ice-supersaturation. This condition is pretty uninteresting from a weather forecasting point of view. There are essentially no ice nuclei (IN), so ice clouds will not form. (The humidity has to go even higher to water saturation before clouds start to form from condensation as described above.)

So these regions are uninteresting, because nothing happens there, so weather forecasters don't track them and are generally unaware of them. They have plenty of other factors to concern themselves with than to worry about persistent contrail formation. They could, I suppose, if enough of the weather forecast following public expressed enough interest in being informed about it.

I was a weather forecaster at one time. I used ti include the occurrence of spectacular mountain wave cloud in my forecasts if I thought, after suitable investigation, there would be some good mountain wave action. Usually the forecaster following me would remove those parts of my forecasts - mountain waves or not. Some people just don't care.

I hope this is useful.

Cortes Island is way up at the head of the sound inside Vancouver Island! I would have thought it was pretty cloudy there on the (greater) west coast due to the eastward movement of the North Pacific weather systems. When you say "which is quite often", how often do you mean?
 
but they never mention the only clouds in the sky will be jet trails.

Actually in the photo posted I see mostly normal cirrus clouds.

Know that the formation of cirrus clouds is a natural occurrence, and will be a pre-cursor to incoming weather changes even if airplanes had never been invented (there is old sailor yore dating back centuries...using clouds to predict storms when at sea).
 
Actually in the photo posted I see mostly normal cirrus clouds.

Know that the formation of cirrus clouds is a natural occurrence, and will be a pre-cursor to incoming weather changes even if airplanes had never been invented (there is old sailor yore dating back centuries...using clouds to predict storms when at sea).

By the angles and linearity though, they could easily be contrail induced cirrus. Hard to tell.
 
Actually in the photo posted I see mostly normal cirrus clouds.

Know that the formation of cirrus clouds is a natural occurrence, and will be a pre-cursor to incoming weather changes even if airplanes had never been invented (there is old sailor yore dating back centuries...using clouds to predict storms when at sea).

thanks all for your comments. I am not a weather expert but I know cirrus clouds from jet trails when I see them, as I said I am a full time sailor with a full view of the sky.

I have seen the jets lay these trails. I have also seen this many times. the only clouds in this picture are jet trails. and further more they spread and block the sun. you might assume these jet trails are cirrus clouds but I seen them laid by the jets and often.

from my observations these jet trails spread across the sky and they never use to. nasa calls them spreading persistent contrails, I have seen this happen any time of the year. in the summer at the end of dry spells when the government predicts. the jets come and the weather changes.

if the sky is blue and the jets cloud the sky I would say this is weather changing and in effect solar radiation management.

some scientests are calling for solar radiation management.

David Keith, a Canadian environmental scientist and Harvard professor, is describing is a controversial form of Geoengineering called Solar Radiation Management.
It may be a crude fix, but, he says it may be just the kind of solution we need to stave off catastrophic climate change in a world that's waited too long to shift away from fossil fuels. http://www.cbc.ca/thecurrent/episode/2014/12/02/renewable-energy-climate-change/

from my observation and others it has been happening for many years.
 
from my observation and others it has been happening for many years.

Yes, contrails have been clouding the sky since the 1940s. It's a byproduct of air travel. There are variosu historical accounts here:
http://contrailscience.com/persisting-and-spreading-contrails/
example:


For scientific discussion, see, for example, all these articles on contrails. In particular the one titled “Airborne Observations of Contrail Effects on the Thermal Radiation Budget“, from 1970:

The spreading of jet contrails into extensive cirrus sheets is a familiar sight. Often, when persistent contrails exist from 25,000 to 40,000 ft, several long contrails increase in number and gradually merge into an almost solid interlaced sheet.
[....]
Contrail development and spreading begins in the morning hours with the start of heavy jet traffic and may extend from horizon to horizon as the air traffic peaks. Fig. 1 is a typical example of midmorning contrails that occured on 17 December 1969 northwest of Boulder. By midafternoon, sky conditions had developed into those shown in Fig. 2 an almost solid contrail sheet reported to average 500 m in depth.​

Content from External Source
 
Spreading contrails are effectively identical to cirrus clouds: the water from the aircraft exhaust is only a tiny fraction (maybe 0.01%) of the total water in a "mature" contrail.

This study by Gaby Rädel and Keith Shine at Reading University (UK) tries to put figures on the additional cloud cover created by contrails: http://onlinelibrary.wiley.com/doi/10.1029/2007JD009117/pdf

You'll see that as far back as 2002, contrail cover was considered to be over 1% for much of the Lower 48 and Western Europe.

upload_2014-12-3_17-20-21.png

However it is quite difficult to say whether or not the cirrus clouds would have formed anyway, in the absence of aircraft. Either way, contrails are considered to have a slight global warming effect, which is the exact opposite of what "solar radiation management" would try to achieve. The two things are not related at all.

You might think it counterintuitive that cirrus blocking the sun would have a warming effect, but in fact although they slightly cool the Earth during the day, they act as a blanket at night and keep temperatures up (nights with clear skies are generally much colder than cloudy nights).
 
thanks all for your comments. I am not a weather expert but I know cirrus clouds from jet trails when I see them, as I said I am a full time sailor with a full view of the sky.

I have seen the jets lay these trails. I have also seen this many times. the only clouds in this picture are jet trails. and further more they spread and block the sun. you might assume these jet trails are cirrus clouds but I seen them laid by the jets and often.

They do look like jet trails here. However, I would like to point out that jet contrails are more or less cirrus clouds, except manmade. Jet contrails are vapor trails that eject moisture into a freezing atmosphere.

from my observations these jet trails spread across the sky and they never use to. nasa calls them spreading persistent contrails, I have seen this happen any time of the year. in the summer at the end of dry spells when the government predicts. the jets come and the weather changes.

Well yes, they can spread like a mat of cirrus, because they bear similar properties--that being deposited water vapor and thus ice crystals. This doesn't always happen of course, as it depends on atmospheric conditions, but it's not unusual.

if the sky is blue and the jets cloud the sky I would say this is weather changing and in effect solar radiation management.

some scientests are calling for solar radiation management.

Jets can cloud the sky, but there is no evidence that it is solar radiation management. There are many proposals for solar radiation management, but conventional atmospheric science explains the behavior of jet contrails to look exactly as depicted on many photographs and youtube videos just fine.

David Keith, a Canadian environmental scientist and Harvard professor, is describing is a controversial form of Geoengineering called Solar Radiation Management.
It may be a crude fix, but, he says it may be just the kind of solution we need to stave off catastrophic climate change in a world that's waited too long to shift away from fossil fuels. http://www.cbc.ca/thecurrent/episode/2014/12/02/renewable-energy-climate-change/

from my observation and others it has been happening for many years.

Poor David Keith. He was actually a professor at one of the Universities I attended, though I never actually attended one of his classes. Seems like a nice guy though. Kind of sucks that his picture gets posted on the dartboards of some individuals out there.

But on the topic, he mentions "sulfuric acid particles" in the "stratosphere." While many jetliners can climb to the lower stratosphere depending on what latitude it is at (the further south the better), and also their weight, the question here is whether or not they are actually doing it at present. Given the article came out yesterday, it seems to be a subject that is still being discussed. Watching the Tedtalk, he also addresses his reservations on geoengineering, and that he would like more exposure on examining his proposals.

But to get to my point, let's ask some important questions here:
First, is what you see explainable by conventional science? If you look at the photos above, and if you can fathom that jet emissions are water vapor deposited into the atmosphere, and that such depositions are similar to cirrus, then the answer should be a yes.

If the answer is still no, then the next question is, what exactly does one think is being left by aircraft?

Is this being done globally or to a sufficient extent that it actually addresses issues with solar radiation and what not?

Where are these aircraft coming from?

What type of aircraft are they?

What supplies these aircraft?

Are there enough aircraft to do this?

Who runs these aircraft?

At some point, if you keep asking the questions, you might encounter a bit of a brick wall. What David Keith proposes is arguably cheap (at least according to him), but it still seems like a large scale operation that wouldn't be a secret either.
 
I have seen this happen any time of the year. in the summer at the end of dry spells when the government predicts. the jets come and the weather changes.

I would suggest that you consider that the conditions conducive to persistent contrails (humid air at flight level) are often found in advance of approaching weather fronts.

The jets are always there...its the weather that changes that allows to contrails to persist.




 
jet are changing the weather. to my observations. lots. you can explain deny or reason or prove otherwise but I have seen jets change many blue sky days grey. and I have proved it. I cannot take to much time proving why or what, I have no idea, just internet babble. but I know what I see. jets change the weather. lots and lots of times. I did not take this video
but I have did observe the jet trails this day.
as to those last photos, I did see short bursts of jet trails that made smaller less long clouds too. those clouds are made from jets. this is after a long hot spell and the weather was a forcasted change. this was the change. jet trails.
 
I appreciate the challenges and I do accept your unwillingness to believe what I see but one day for your own good you may. I am not making this up. jets change the weather. lots. believe what or why you want. I only can show you what I see. I can reason and I can show you. it is hard to believe jet grey our skys enough that people are pissed, but
that I can prove.
 
I appreciate the challenges and I do accept your unwillingness to believe what I see but one day for your own good you may. I am not making this up. jets change the weather. lots. believe what or why you want. I only can show you what I see. I can reason and I can show you. it is hard to believe jet grey our skys enough that people are pissed, but
that I can prove.

Jets do change the weather a bit, nobody has ever denied that. In fact it was in the news 35 years ago.
 
not just sailors like me think this. ex premier of b.c. canada bill vanderzalm is a chemtrail activist. the whole council of redding California agreed because of citizens discontent to measure nano particles geoengineering and chemtrails.
 
I don't care how or why... jets change the weather. more over I see the government agents predict these jet clouds.
 
not just sailors like me think this. ex premier of b.c. canada bill vanderzalm is a chemtrail activist. the whole council of redding California agreed because of citizens discontent to measure nano particles geoengineering and chemtrails.
You are making a huge (and incorrect) leap from "jet contrails increase cloud cover" (which they do) to talking about "nano particles" and geoengineering.

How could a "chemtrail" that wasn't made of water spread out and form a cirrus cloud? It couldn't - it would be impossible. The very fact that contrails can spread out into cirrus is proof of the fact that they are in fact made of water - or, to be more specific, ice crystals.
 
oh wait. I see only jet trails. I make a distinction from what I see and what i read. I bring this up to show how many care that jets change the weather. not a little. I think even if the chemtrail folks are wrong it is a metaphor for how much the citizens think the government hates them. that the government would spray all of us for our own good is the stuff of science fiction and fact.
 
I appreciate the challenges and I do accept your unwillingness to believe what I see

long slender clouds do not spread and grey the whole sky

We do believe what you see...that contrails often persist and spread and if there are enough of them create a sheet of cirrus clouds.

This research paper from 40 yrs ago describes EXACTLY what you see today...and what you believe didn't used to happen:

"It is often observed that contrails spread considerably...Under favorable conditions, a lateral spread of kilometers is observed...If sufficient air traffic exists, an entire overcast of contrail cirrus may develop and persist for hours with rapid growth in the ice budget of individual contrails."
Content from External Source
http://ciresweb.colorado.edu/science/groups/pielke/classes/atoc7500/knollenberg72.pdf


Its not a new phenomenon...its been observed for as long as planes have flown high enough...but there are a lot more planes in the sky than 40yrs ago.

BTW- nothing David Keith has researched or advocated involved visible, persistent trails from commercial jets.
 
so jets change the weather enough to make many people depressed such any cloudy day and that is ok? is it ok if the government and some scientests agree to make more persistant spreading contrails for our own good?
 
so jets change the weather enough to make many people depressed such any cloudy day and that is ok?

I can only speak for myself but I do not get depressed when I see persistent contrails. They are a trade-off with the benefits of air travel. Its a trade off I am ok with.

is it ok if the government and some scientests agree to make more persistant spreading contrails for our own good?

No scientists or governments have agreed to do this so or are even suggesting do so....so, the question is moot
 
I think even if the chemtrail folks are wrong it is a metaphor for how much the citizens think the government hates them. that the government would spray all of us for our own good is the stuff of science fiction and fact.

It appears you came with the preconceived idea that the government has to be involved in jet trails. No one here is advocating that you bend for a government. Jets in general are known to leave contrails that may potentially spread, and this is the point that for some odd reason, keeps getting twisted in such a way that somehow some top-secret supershill government agency is "spraying" the populace against their will.
 
ex permier bill Vander Zalm requested information on climate-control engineering being done by the government. Many suspect that cloud-like streams left by airplanes are chemical trails, or “chemtrails” that contain unknown substances used to alter the weather.
The former B.C. premier received 47 pages of documents from the federal government. Six pages were blank, and 10 pages had some portions blacked out.
The retired politician said that the papers prove that Canada is into geo-engineering. “There’s no doubt about it,” http://www.straight.com/news/650216...s-canadian-government-geo-engineering-climate
 
ex permier bill Vander Zalm requested information on climate-control engineering being done by the government. Many suspect that cloud-like streams left by airplanes are chemical trails, or “chemtrails” that contain unknown substances used to alter the weather.
The former B.C. premier received 47 pages of documents from the federal government. Six pages were blank, and 10 pages had some portions blacked out.
The retired politician said that the papers prove that Canada is into geo-engineering. “There’s no doubt about it,” http://www.straight.com/news/650216...s-canadian-government-geo-engineering-climate

Okay, so an ex Premier follows the chemtrail movement. Or another way of saying this is that he buys into a fringe theory. Does that seem surprising to you given that he's probably not an atmospheric scientist, meteorologist, nor a pilot? Or do you think that actually proves that jets are "spraying"?

Perhaps it will be more enlightening to actually see this document.

Here's Environment Canada's response to the ex premier:
http://www.straight.com/news/412071...st-rejects-bill-vander-zalms-chemtrail-theory

Meteorologists naturally reject chemtrails of course. I guess one can say that since Environment Canada is part of the "government," they might be in on it as well. But man, the coverup gets bigger every time!
 
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so jets change the weather enough to make many people depressed such any cloudy day and that is ok? is it ok if the government and some scientests agree to make more persistant spreading contrails for our own good?
Again, you have a major misconception. Nobody is deliberately making more contrails. In fact scientists would like to DECREASE the amount of persistent contrails, because they increase the global warming effect, which "solar radiation management" would try to decrease.

Solar radiation management, or geoengineering, has nothing to do with contrails. It would involve spraying doplets (probably sulfate) way up in the stratosphere, almost twoce the altitude that commercial jets fly at. These would be invisible from the ground, and the aircraft releasing them would not be leaving contrails either.

There have been studies of how to reroute aircraft to avoid areas where contrails would form. This would reduce their environmental impact, but would make flights longer and more expensive, so don't expect that to happen!
 
@ Spiral,

I really suggest reading through the whole contrail section of this site and see how the evidence stacks up. On one side there is a lot of 'chemtrail' claims, based on bad science, conspiracy theory paranoia, extremely lateral thinking and inexpert observation that jump to illogical conclusions and seam to suggest that these lines in the sky are Government / NWO / alien lizard people / crazed scientists / (insert fave bad guy here) - plans to - control population / control our minds / induce weather warfare / change the climate / (insert fave reason here).

On the other hand there is a lot more evidence based on sound science, informed observation, knowledge of the aerospace and aviation industry, political and economic analysis, historical archives etc that shows that contrails are a well known and well studied phenomena, which have been around since at least WW1 and while they do have some environmental impact, are in no way the big bad fingers of cloudy death the conspiracy crowd will have you believe.

There are also threads that show you how you can check the evidence for yourself, right down to the ability to check which plane is laying which trail, and how the weather will effect and is effecting what you are seeing.

And here you will find reasoned arguments and debate around this (and many other subjects). Despite what critics of this site and others like it will have you believe, we are not right wing government dis-info agents, shills, sheeple and NWO plants seeking to hide and bury the truth. We are seeking answers and truth like everyone else, It is just that people here like to weigh up all available evidence before reaching conclusions, and all to often the real evidence, once picked over and analysed points to far more mundane answers than the knee jerk paranoia the CT crowd thrive on. We also welcome debate and counter argument, provided it can be backed up with hard evidence. Try posting contrail evidence on a chemtrail site and then count the seconds before your insulted and banned.

And one final point, yes your right, scientist and climatologists are debating if contrails and the possibility of very high altitude 'spraying' could in someway stablise the global climate. Here's a few links you may find of interest..
http://www.bbc.co.uk/news/world-africa-30229874
http://www.bbc.co.uk/news/science-environment-30197085
(I posted a few quotes from these links yesterday in another thread so wont repeat them here)

BUT as the above stories explain, scientists are also well aware of the potential fall out, environmentally, politically and economically of such actions and lay out as many reasons why the idea is a bad idea as they say are good.

Hope you enjoy your stay and the debates and all that is asked for in return is politeness and a mind that is open to analytical deduction.
 
the whole council of redding California agreed because of citizens discontent to measure nano particles geoengineering and chemtrails.

OK. Are the results of that testing available or are you jumping to a conclusion about what they might show?
 
the whole council of redding California agreed because of citizens discontent to measure nano particles geoengineering and chemtrails.

I don't think they actually agreed to do that. Just maybe look into the topic a bit more.
 
Spiral please focus and show that you have read and properly considered people's replies to you. (you don't have to reply to them all, but it seems like you are just brushing off people's points.)
Remember, the stratosphere - where the proposal to do solar radiation management would happen - is not the level at which you see clouds or where planes fly; and contrails have definitely spread out and lingered long before now so you saying they never used to is wrong.

Are you aware of how much traffic is flying above you that aren't leaving persistant contrails right now? https://flightaware.com/live/
Try and get an idea of how much traffic there is at any given time over your head, now imagine what happens when the conditions are right for contrails to persist and spread, which will often be ahead of an approaching front, just as the weathermen predict.
If you observe a contrail being laid, you can post your information here and users can track down what flight it is likely to be.
 
jet are changing the weather. to my observations. lots. you can explain deny or reason or prove otherwise but I have seen jets change many blue sky days grey. and I have proved it. I cannot take to much time proving why or what, I have no idea, just internet babble. but I know what I see. jets change the weather. lots and lots of times. I did not take this video but I have did observe the jet trails this day.
as to those last photos, I did see short bursts of jet trails that made smaller less long clouds too. those clouds are made from jets. this is after a long hot spell and the weather was a forcasted change. this was the change. jet trails.

The photos I've posted above were to debunk your OP claim:
they never mention the only clouds in the sky will be jet trails. (emphasis mine)
There were not only jet trails but natural cirrus clouds. Let's look at a big picture. Here are the MODIS satellite images taken on July 17, 2014. The Terra image of the area was taken at 19:40 UTC (12:40 PDT):

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=AERONET_Saturn_Island.2014198.terra.250m

The Aqua image was taken about two hours later, at 21:25 UTC (14:25 EDT):

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=AERONET_Saturn_Island.2014198.aqua.250m

There are plenty of contrails above Vancouver Island in both images. The busy traffic between Asia and the States is joined here by the flights between the West Coast and Alaska. There are natural cirrus clouds too, carried by the high altitude wind across the air traffic routes. This wind also blows away contrails: some well spread contrails seen near Hernando Island in the Terra image are not there in the later Aqua image. The wind speed at the contrail altitudes can be about or even above 100 mph (faster than a car), so the contrail from a plane that passed above you would disappear out of view in less than two hours. The haze you may see at that time would have come from a different place hundred miles upwind.

The aged contrails in your OP picture probably were formed on the other (Pacific) side of Vancouver Island and then carried further inland, together with natural cirrus clouds formed at the island's North and South ends.
 
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ex permier bill Vander Zalm requested information on climate-control engineering being done by the government. Many suspect that cloud-like streams left by airplanes are chemical trails, or “chemtrails” that contain unknown substances used to alter the weather.
The former B.C. premier received 47 pages of documents from the federal government. Six pages were blank, and 10 pages had some portions blacked out.
The retired politician said that the papers prove that Canada is into geo-engineering. “There’s no doubt about it,” http://www.straight.com/news/650216...s-canadian-government-geo-engineering-climate

From the article:
"Many suspect that cloud-like streams left by airplanes are chemical trails, or “chemtrails” that contain unknown substances used to alter the weather."
Content from External Source
Suspicions do not equal evidence. This is just the usual claims based on the supposedly "odd" appearance of contrails and the idea that normal contrails aren't supposed to persist, which is demonstrably wrong.
 
The aged contrails in your OP picture probably were formed on the other (Pacific) side of Vancouver Island and then carried further inland, together with natural cirrus clouds formed at the island's North and South ends.
the winds were very slow that day and the jets trails did age, right in front of my eyes not on the other side of the Vancouver islands. they also continued to spread and somehow there was a thunder storm the next day all predicted days before by government weather agents. I did not see any natural clouds on those days except for a haze over Vancouver island seen from lund b.c.
 
the winds were very slow that day and the jets trails did age, right in front of my eyes not on the other side of the Vancouver islands. they also continued to spread and somehow there was a thunder storm the next day all predicted days before by government weather agents. I did not see any natural clouds on those days except for a haze over Vancouver island seen from lund b.c.
Wind speed at sea level and wind speed at altitude can be very different, a calm still day on the ground doesn't mean a calm still day at 30,000 feet.
 
this was a pattern all hot summer long. they sprayed all day today too. I know what I see. jets are changing the weather and thousands agree many don't believe their own eyes. I know what I see and I hear, the government even predicts cloudy days when the only clouds are jet trails.
 
Wind speed at sea level and wind speed at altitude can be very different, a calm still day on the ground doesn't mean a calm still day at 30,000 feet.
I don't know the wind speed. I saw the jets . I took pictures of them. I watched them spread all day
 
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