Debunking "Contrails don't Persist" with a Study of 70 Years of Books on Clouds

Graham2001

Active Member
A 1905 book on clouds has been uploaded to Project Gutenberg, the scans of the illustrations are not perfect, but the show quite clearly that clouds back then look like clouds now.

Cloud Studies by Arthur W. Clayden (1905)

http://www.gutenberg.org/ebooks/55126

The authors introduction recommends the book to meteorologists, artists and anyone who is interested in the sky.
 

SR1419

Senior Member.

mikret

New Member
Result: Every single book on clouds that I could find for the last 70 years says that contrails can persist for hours.


can persist for hours - --
I'm not sure that a few hours, but I'm sure that I watched 30-40 minutes ..
everything depends on the weather and the airplane.
 

Mick West

Administrator
Staff member
can persist for hours - --
I'm not sure that a few hours, but I'm sure that I watched 30-40 minutes ..
everything depends on the weather and the airplane.

To see them persist for hours you usually have to look at satellite image, as the wind has generally carried them out of view after a couple of hours. They also spread out, and it's hard to distinguish them from other clouds.

I think more commonly people see contrail cover that last hours, and don't realize it's from different contrails. Like:
Source: https://www.youtube.com/watch?v=kQekGClN5GE
 

L. Baker

New Member
One problem I have in telling people that contrails can actually persist, and can even spread out to cover the sky, is that people tend to be suspicious of random people on the internet. So I decided to simply let 70 years of books on clouds speak for themselves.
There are many things to consider when talking about contrail formation. Just off the top of my head, and not in any particular order:

1. Atmospheric profile (temperature, humidity, and pressure with respect to height.)
2. Partial vapour pressure with respect to ice.
3. Partial vapour pressure with respect to water.
4. Condensation (or sublimation) nuclei.
5. Cosmic radiation levels.
6. Fuel and exhaust gas composition.
7. Aircraft velocity.
8. Aircraft elevation.
9. Aircraft type
10. Engine types and configuration.
11. Wake turbulence.
12. Exhaust turbulence.
13. Exhaust velocity and volume.
14. Atmospheric winds
15. Season
16. Time of day
17. Latitude and longtitude
16. Angle of view
17. Sizes, shapes, and properties of constituent water droplets or ice crystals.
18. Additional layers of clouds or contrails)
.

Remember that all of these things determine what a contrail will look like from the ground. You cannot start with the "look" of or shape of a contrail and make statements about what all the determining factors are. That is pure silliness and is a trap that many fall into.
 
Last edited by a moderator:

Mick West

Administrator
Staff member


This has been posted before, but the version I saw before was the reprint without the last paragraph. This is the original, from:
https://books.google.com/books?id=N...ts=bpfzssIufW&pg=RA4-PA13#v=onepage&q&f=false


Cloud Formation by Supercharged Plane

An altitude flight was made in the morning at McCook Field, recently, by Lieut. J. A. Macready in a LePere with supercharged Liberty. When the airplane reached a height of 26—27,000 feet at 11.50 a. m., a long feathery white streamer was observed forming behind a rapidly moving dark speck. The cloud was of the cirrus variety, well defined at its edges and apparently ten to fifteen times the width of the plane. The sky behind the first portion was clear blue with no other clouds in the near neighborhood. The first streamer seemed perhaps two miles long. Then a gap of one-quarter mile. The second streamer formed with a background of light cirrus cloud and after two or three miles the plane seemed to go into the cirrus background for the streamer formation ceased while an apparent path of blue continued beyond for a way in the cirrus cloud. The whole streamer may have been three miles long. After twenty minutes the streamer had drifted and spread until it merged indistinguishably with the other cirrus clouds visible. The weather conditions at the time were generally very clear, warm, with perhaps 0.1 of the sky in cirrus clouds.

The observer reported as having observed nothing unusual; occasionally the motor would give a burst of black exhaust gas. The pilot thought he remembered having passed through a stratum that felt damp. Clouds at this altitude are necessarily ice crystals, or needles, and it is difficult to determine the cause of the cloud formation under consideration. Possible contributing causes are: Water in exhaust; dust and carbon particles in exhaust serving as cloud nuclei; convective currents due to disturbance caused by passage of plane. Conditions of humidity were undoubtedly ideal for the formation of cloud at that altitude.

Content from External Source
It's interesting because even back then, in the very first few times that planes had flown at that altitude, the causes of contrail cloud formation were broadly understood.
 

Mick West

Administrator
Staff member
Lieutenant MacReady was quite the badass back then, there's more detailed accounts of his flights here:
https://media.defense.gov/2011/Apr/25/2001330216/-1/-1/0/110425-D-LN615-004.pdf

With some early chemtrailing (Actually cropdusting, also in 1921):
Metabunk 2018-02-17 10-26-14.jpg

His own account of the 1921 flight (attached) is fascinating, although he does not mention the contrails — presumably not having seen them form behind him (or it might actually have been a later flight)
 

Attachments

  • Pages 289-292 from MacReady 110425-D-LN615-004.pdf
    450.7 KB · Views: 572
Last edited:

Graham2001

Active Member
Not a book, but a 1920 film (With modern royalty free music.) about clouds by the US Department of Agriculture, again it shows that clouds back then are no different from clouds now.

 

Leifer

Senior Member.
Ere
20181214_123335.jpg 20181214_123322.jpg 20181216_003058.jpg 20181216_003155.jpg Here are some photo records of an encyclopedia from 1988...describing "contrails".
This evidence was found in a "group buy" of cheap, nearly uselessbooks for theatre background decoration.
One of them was World Encyclopedia 1988.
 

Trailblazer

Moderator
Staff member
Not a cloud book, but I'm reading the diaries of the politician Alan Clark (1928-1999), and this entry from summer 1983 caught my eye:

upload_2019-4-17_11-43-53.png

Google Books link

Clearly describing persistent spreading contrails over southern England.
 

Scaramanga

Member
Chemtrail advocates often say that they've only started seeing parallel lines of cirrus type clouds in the sky in recent years. Well...one of the things I inherited from a relative who was in the RAF Royal Observer Corps was a copy of the 1938 Meteorological Glossary. And here is what it says on cirrus clouds...


img163.jpg
 

Normah

New Member
One problem I have in telling people that contrails can actually persist, and can even spread out to cover the sky, is that people tend to be suspicious of random people on the internet. So I decided to simply let 70 years of books on clouds speak for themselves.


Result: Every single book on clouds that I could find for the last 70 years says that contrails can persist for hours.

The problem is that we're seeing persistent contrails in the dead heat of summer which is nowhere near -40 C.
 
Last edited by a moderator:

Miss VocalCord

Senior Member.

Attachments

  • 1580752168828.png
    1580752168828.png
    333.3 KB · Views: 397
Last edited:

Trailblazer

Moderator
Staff member
The problem is that we're seeing persistent contrails in the dead heat of summer which is nowhere near -40 C.
Many passenger airliners have information displays on the TV screens on board which show the current altitude, speed, location and often the external air temperature. Have a look next time you are on a plane. No matter how hot it is on the ground, chances are it will be somewhere in the -40C range or below when you are at cruising altitude.

1580991928214.png
 

Alexandria Nick

Active Member
Almost counter-intuitively, higher surface temperatures actually increase icing conditions at altitude. Specifically, small ice crystals affecting engines and sensors are more likely to form in relation to thunderstorm systems and tropical storms, two places with surface temperatures higher than normal. Most of the research right now is going into figuring out what size the ice crystals are and how, exactly, they're formed because they currently can't be tracked on radar.

https://journals.ametsoc.org/doi/full/10.1175/JTECH-D-15-0246.1
Flights 12 and 13 were the only flights to be performed in the same long-lasting quasi-stationary system, a tropical storm, and for these two flights, the concentrations of large ice particles were found to be higher than in all other clouds sampled at the same temperature level. MMDs mostly exceed 500 μm and even reached 2 mm. Moreover, in these flights MMD tended to increase with increasing TWC, the opposite trend found for the classical shorter-lived oceanic MCS.
Content from External Source
What that's saying is that in the course of that particular study, that the areas around a tropical storm were producing more ice at altitude than regular thunderstorms, despite the temperature at altitude being the same. The higher water and surface temperatures under a tropical storm are lofting more moisture up to the level where ice can form, because there's a higher rate of evaporation.
 
Top