Comment: For skeptics of this 2010 article the ambiguity of disinformation is contained in the sections colored in blue:
(1) “significant amount of moisture” is intentionally vague. The USAF contrail science facts document requires that relative humidity (RH) be near saturation. The definition of saturation is a RH in excess of 80- 90% at the altitude where the aircraft is flying. USAF Contrail Facts Says:
” If the atmosphere is near saturation, the contrail may exist for some time. Conversely, if the atmosphere is dry, the contrail will dissipate quickly.”
The sky image in the article below shows no atmospheric data to confirm the white lines in the sky are actually persistent contrails of water vapour. It would be more correct to say these lines appear to be “persistent jet trails” of unknown emissions content. The RH above 25,000 feet in this photo is statistically far more likely to be < 40% rather than > 80 to 90%. We know this because high altitude atmospheric conditions are measured and archived to allow anyone to demonstrate the rarity of near-saturated conditions of RH above 25,000 ft to their personal satisfaction. Investigator, Cliff Carnicom published data on this issue and anyone can create their own spread sheet from the U. Wyoming archives to duplicate Carnicom’s findings. (Carnicom research)
(2) “The level of moisture in the air at high altitudes is unrelated to weather conditions at ground level, which is why it is possible to see contrails on a clear day.”
It’s a quantum stretch to imply that the atmosphere above 25,000 feet is frequently saturated with water vapour when historic data establishes near-saturated conditions above this altitude are “rare”
Carnicom commented on the attempt to disinform the public as he exposes NASA’s duplicity as “Brazen Propaganda” (more)
Finally, many good people are overwhelmed by the enormity of this conspiracy to mislead the public on the criminal contamination of our breathable atmosphere – an unalienable right. But too may of us have decoded the crimes of mass deception perpetrated by “the dark side” of unelected bureaucrats and appointed gangsters.
Attack of the vapours – how jet trails block out the sunshine (source)
By Oliver Tree
UPDATED: 28 June 2010
If you are jetting off for an exotic holiday this summer, spare a thought for those you leave behind.
Because it seems that sun-seekers are responsible for leaving the rest of us languishing under grey skies – thanks to the emissions from aircraft engines.
These vapour trails create clouds which, experts claim, can block out sunlight for millions. This is the reason that our skies appeared unusually blue when the Icelandic volcano Eyjafjallajokull was erupting, and all flights over Britain were banned.
The phenomenon occurs when aircraft fly above 25,000ft, where the air temperature is around minus 30C. This causes water vapour emitted by the engines to crystallise and form the familiar white streaks across the sky, known as contrails.
These can be short-lived. But if there is already a (1) significant amount of moisture in the atmosphere they can linger for hours, as the (2) excess water vapour from the engines tips the surrounding air past its saturation point.
This acts as a catalyst to speed up the natural process of cloud formation. Cirrus clouds – the wisp-like formations seen at high altitude – begin to form around the contrails.
The level of moisture in the air at high altitudes is unrelated to (2) weather conditions at ground level, which is why it is possible to see contrails on a clear day.
Reading University’s Professor Keith Shine, an expert in clouds, said that those formed by aircraft fumes could linger ‘for hours’, depriving those areas under busy flight paths, such as London and the Home Counties, of summer sunshine.
‘People from abroad are amazed by the number of vapour trails in the skies over London,’ he said. ‘When the air is wet enough, the cloud formed by contrails can last for hours.’
Experts have warned that, as a result, the amount of sunlight hitting the ground could be reduced by as much as ten per cent. Professor Shine added: ‘Over the busiest areas in London and the South of England, this high-level cloud could cover the sky, turning bright sunshine into hazy conditions for the entire area. I expect the effects will get worse as the volume of air traffic increases.’
In a 2009 Met Office study into the effects of contrails, scientists from a number of UK institutions used a weather satellite to track a large military aircraft as it circled over the North Sea. The team expected high-level winds to disperse its contrails without trace.
But instead they helped to form clouds, which the researchers were astonished to find eventually covered a massive 20,000 square miles.