The chemtrails ruined my blue sky! Here's why...

a reply to: Tucket

contrails are man made clouds. They form the same way clouds do. Here is a bit of info on that.

Clouds form when the invisible water vapour in the air condenses into visible water droplets or ice crystals. There is water around us all the time in the form of tiny gas particles, also known as water vapour. There are also tiny particles floating around in the air - such as salt and dust - these are called aerosols.

link to more knowledge.

a reply to: network dude
So why wasnt there any natural cloud formation in the sky at 9am in Robs first pics?

a reply to: Gatman30

I'm not very educated on the subject, what is a contrail? And why are so many people saying that chemtrails are a myth? a reply

Here maybe these will help.

science.howstuffworks.com...

contrailscience.com...

conspiracies.skepticproject.com...

a reply to: Tucket

There is some in those first images, increasing later on. The earlier lack of them could be down to lower relative humidity or lack of aerosols to trigger the process. Flights can be the trigger for cloud formation if RHI is high enough but CCN's aren't sufficiently abundant already.

Why do you think it's related to the heat of the exhaust?

a reply to: Tucket

So why wasnt there any natural cloud formation in the sky at 9am in Robs first pics?

Well if the nuclei isn't there for a cloud to form they won't. Unlike a contrail that creates the nuclei for the contrail to form which is why you didn't see clouds but did see the contrails to form.

Does that help answer your question?

Just in case here you go...

Now, boys and girls, CLOUDS need two elements in order to form -- particles and moisture. They require condensation nuclei (small particulates) for water vapor to adhere to. The size of these nuclei is about seven microns (picture a red blood cell). Clouds also need conditions of about 70% humidity before they amass at various levels of our troposphere. Clouds hang around for a long time, and come in basic varieties: cirrus (high altitude, feathery looking), cumulus (puffy and fat, with noticeable vertical dimension), and stratus (low-hanging ... those sheets of gray that create an overcast day).

www.aboutthesky.com...

originally posted by: Tucket
a reply to: Rob48

"Within less than an hour the trails were expanding and merging into cloud."

Thats well before the moisture rolled in.

Within an hour of the trails starting to form. As I said they started at about 9.30.

"The small amount of ice in the exhaust provides nucleation sites for cloud."

But theres only a limited amount of crystals formed due to the limited amount of heat available. Are you suggesting that hours after the Jet has passed, there is still exhaust heat available for nucleation?

What do you mean? Heat doesn't cause nucleation. Quite the reverse: the exhaust has to cool down and let the water condense, then freeze. That's why there is a short gap after the engines with no visible trail: the exhaust is too hot at first.

Because the air was too dry. That is the whole point of this thread! Once the air becomes moister, the trails can start to form.

Look at the charts. The air went from less than 30% humidity to over 90%. Here is the map with the scale on. 06z = 7am BST.



At 8 am it was clear blue sky. At around 9am I saw a few patchy bits of contrail here and there. By 9.30 there was a proper grid pattern. By 10 there was lots of cloud.

My point is that you only see contrails forming when the moisture is high enough.

Lots of people seem to think the trails cause the weather to change, but in fact it is the coming change of weather that makes the trails visible!

originally posted by: Rob48

originally posted by: Tucket
a reply to: Rob48

"Within less than an hour the trails were expanding and merging into cloud."

Thats well before the moisture rolled in.

Within an hour of the trails starting to form. As I said they started at about 9.30.

"The small amount of ice in the exhaust provides nucleation sites for cloud."

But theres only a limited amount of crystals formed due to the limited amount of heat available. Are you suggesting that hours after the Jet has passed, there is still exhaust heat available for nucleation?

What do you mean? Heat doesn't cause nucleation. Quite the reverse: the exhaust has to cool down and let the water condense, then freeze. That's why there is a short gap after the engines with no visible trail: the exhaust is too hot at first.

Arent you answering your own question? In order for nucleation there must be subcooling taking place, right?

originally posted by: Rob48
Because the air was too dry.

So why then did the Contrails continue in their formation if the air was too dry?





edit: I have to take off for a while. Ill stop by in an hour or so.

a reply to: Rob48

Instead of looking up try looking down and around. Yes we are sky people. We live in the sky/atmosphere. But our feet are on the ground. Around us the environment we live in is greatly affected by the amount of light reaching us. That is affected strongly by the jet exhaust above us. A clear blue sky is accompanied by a healthy environment in which 'natural' amounts of light reach us. A heavily polluted sky is accompanied by a dull immediate environment. Congratulations on bringing some science to the chemtrail/contrail dilemma. But really isn't this all misdirection? The important issue affecting us is the health or ill health caused by the use of these silly jet powered passenger planes.

When people of whatever persuasion complain about the lack of a 'normal' blue sky what they are really affected by is the lack of light at ground level caused directly by ill-advised individuals buying tickets, waiting in queues, and flying off to god knows where for whatever ridiculous reason. I know people who have travelled long distances by sailboat, bicycle and on foot. If you really need to travel you can do it that way. Chemtrail issue over.

a reply to: Kester

That is affected strongly by the jet exhaust above us.

And this isn't affected by clouds, as they are more prevalent daily than contrails in the world?

a reply to: Kester

waiting in queues, and flying off to god knows where for whatever ridiculous reason. I know people who have travelled long distances by sailboat, bicycle and on foot. If you really need to travel you can do it that way. Chemtrail issue over.

If it were only that easy.

And that wouldn't stop the chemtrail issue, as the believers will just come up with something else they consider chemtrails.

They have been doing it since the mid 90's, and will go strong as long as there is money to be made from the gullible.

a reply to: tsurfer2000h

Arguable from observation here.

a reply to: tsurfer2000h

T shirts, anyone? I totally agree with you there. Debt based fiat currency supplied by private financiers can be easily accumulated by misleading the gullible.

originally posted by: Kuroodo

I think you mean "contrail" and "persistent contrail".

Two planes travelling at just a couple of thousand feet different altitudes can produce very different contrails:



In this example a plane at 35,000 feet would be in close to 100% humidity and leave a persistent trail, but one at 38,000 feet wouldn't.

That chart shows you just how sharply the conditions can change between two flight levels.

In my post above I said "subcooling" when I shouldve said "supercooling." Apologies..Its been awhile since refrigeration school.

a reply to: Rob48

I have a question OP can they turn on/off the spraying? I was at work the other day taking a break and noticed a plane in the sky leaving a contrail I just assumed it was normal until it looked like some one took an eraser to part of the trail. This happened a about 5-6 times across the sky. It was like they were turning it on/off.

originally posted by: tsurfer2000h
a reply to: Tucket

So why wasnt there any natural cloud formation in the sky at 9am in Robs first pics?

Well if the nuclei isn't there for a cloud to form they won't. Unlike a contrail that creates the nuclei for the contrail to form which is why you didn't see clouds but did see the contrails to form.

Does that help answer your question?

Almost, Surfer. But I also want to know why Contrails continue to form even after there is no heat left for supercooling(the nucleation process).

originally posted by: SubTruth
a reply to: Rob48

I have a question OP can they turn on/off the spraying? I was at work the other day taking a break and noticed a plane in the sky leaving a contrail I just assumed it was normal until it looked like some one took an eraser to part of the trail. This happened a about 5-6 times across the sky. It was like they were turning it on/off.

No of course they can't "turn it off". It's the exhaust of the jet engine. Turning off the engines in flight is generally frowned upon.

What you were seeing was air close to the critical humidity level. Some areas were moist enough for trails to form but some weren't.

Like this (a photo I took last week)