Lots of contrails yesterday: Beautiful contrails tens of miles long: The ice particles descending to the ground, getting wider as time passes. But I could be wrong.

Streets Loc: Euless, TX.

Beautiful contrails tens of miles long: The ice particles descending to the ground, getting wider as time passes. But I could be wrong.

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Architect1776 Loc: In my mind

Streets wrote:

Beautiful contrails tens of miles long: The ice particles descending to the ground, getting wider as time passes. But I could be wrong.

PaulBrit Loc: Merlin, Southern Oregon

Contrails are a good sign of atmospheric pressure with long contrails indicating lower pressure and short ones higher pressure. Lovely photographs!

howIseeit Loc: Kootenays, BC Canada

PaulBrit wrote:

Contrails are a good sign of atmospheric pressure with long contrails indicating lower pressure and short ones higher pressure. Lovely photographs!

Of course.... Mask adviseble for taking picture at time of such natural phenomen...

RCJets Loc: Virginia

PaulBrit wrote:

Contrails are a good sign of atmospheric pressure with long contrails indicating lower pressure and short ones higher pressure. Lovely photographs!

I have never heard of contrails being associated with pressure. Pilots set their altimeters to standard pressure (29.92 ) above 18,000 ft. That assures that an aircraft flying from one location that may have a low pressure meeting another aircraft coming from a high pressure area will be guarented seperation based on using the same altimeter setting.

Contrails are really based on the moisture content at the altitude they are flying at. A lot of lingering contrails would indicate a high moisture content at the altitude they are at.

frankraney Loc: Clovis, Ca.

RCJets wrote:

I have never heard of contrails being associated w... (show quote)

Just what I thought. But, since it's is frozen moisture, it has been as is posted here.

selmslie Loc: Fernandina Beach, FL, USA

frankraney wrote:

Just what I thought. But, since it's is frozen moisture, it has been as is posted here.

Ice is frozen water.

If the moisture content (water vapor) is too high and the temperature is below freezing, moisture can turn directly into ice. This can happen when an airplane passes through air that is nearly saturated with water vapor. The result is a contrail.

There are no other chemicals involved besides H2O and air but a little bit of dust in the air can provide a place for the water molecules to get together.

Ice can also transform directly into water vapor by sublimation, without passing through the liquid state.

That's why you can put wet laundry on the clothesline in freezing conditions and it will first freeze but ultimately it will dry without getting wet again.

For a full explanation see Why doesn't the moisture freeze out of the air when the air temperature is below freezing?

frankraney Loc: Clovis, Ca.

selmslie wrote:

Ice is frozen water. br br If the moisture cont... (show quote)

Scotty, I understand. What I was doing was replying to, and agreeing, that contrails are described as being caused by jets, and they have been mentioned here as the op did, several times, because I think what the op has posted have also become known as contrails.

Btw, military jets mix environmental air with the exhaust to minimize contrails.

selmslie Loc: Fernandina Beach, FL, USA

frankraney wrote:

Scotty, I understand. What I was doing was replying to, and agreeing, that contrails are described as being caused by jets, and they have been mentioned here as the op did, several times, because I think what the op has posted have also become known as contrails.

Btw, military jets mix environmental air with the exhaust to minimize contrails.

There were contrails before jets arrived. They were common during WW2.

They come about from a disturbance in the air at the right combination of altitude and water vapor content when disturbed by any object that is large enough and moving at the right speed. Internal combustion is not a prerequisite.

Streets Loc: Euless, TX.

howIseeit wrote:

Of course.... Mask adviseble for taking picture at time of such natural phenomen...

You seem to be on my frequency. No one commented on the "ice falling to the ground" If you are interested in coal ash, google "the Dan River tragedy". Another reason why coal ash is considered to be what they are dumping at 45,000 feet.

Streets Loc: Euless, TX.

Ten days later. same time and shooting position. It was about the same temperature. Why no contrails? Have they stopped flying?

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selmslie Loc: Fernandina Beach, FL, USA

Streets wrote:

Ten days later. same time and shooting position. It was about the same temperature. Why no contrails? Have they stopped flying?

Just by looking at the clouds you can tell that the weather was different in your original post than it was for this last image.

Here are two simple Google searches that took only a couple of seconds each:
Weather Whys: Why do airplane contrails form on some days but not others?
Why do airplane contrails form on some days but not on others?

Do you really need this to be spoon-fed to you?

This is elementary school general science. Most of us understood it by the time we graduated from eighth grade. Why didn't you?

Streets Loc: Euless, TX.

There were no natural clouds in any of the photos submitted. I have been associated with aviation since the age of fourteen when I worked at the Detroit City Airport as an aircraft polisher and mechanics helper. Four years of fighter fire control systems. A year plus with Convair on F102 fire control system. Two years as a tech rep on fire control systems. Six years as a field engineer with General Precision/Link on various flight simulators, Including the Apollo Mission Simulator at MSC Houston. Next came two years at American Airlines as Link field engineer on their first digital flight simulator which culminated in my joining the airline where I remained for 26 years in the simulator engineering group at their Flight Academy.

selmslie Loc: Fernandina Beach, FL, USA

Streets wrote:

There were no natural clouds in any of the photos submitted. I have been associated with aviation since the age of fourteen. ...

The first image contains cirrus clouds above the contrails. The second image has cumulus clouds that are much closer to the ground. Both types of clouds are natural and common.

Take a look at examples of natural cloud types: Cloud Classifications and Characteristics. It explains high level clouds (above 20,000 feet) where you will find clouds whose names that begin with "cirro". That's where you are likely to see contrails. It also describes the kinds of clouds below 20,000 feet where contrails are rare.

Despite your fixation on contrails we have to wonder why you have never learned about any of this. Have you ever been up in an airplane?

Did you look at the link I sent to you from the Smithsonian Magazine Science Officially Debunks Chemtrails, But the Conspiracy Will Likely Live On? It contains the following hilarious comment: According to Public Policy Polling, about five percent of Americans believe in chemtrails. That’s more than the four percent who believe lizard people are taking over our politics... Do you also believe in lizard people?