Uveliko pocela implementacija plana za smanjenje broja ljudi

Condensation Trails ("contrails")
from Aircraft Engine Exhaust
Contrails (short for "condensation
trails") are line-shaped clouds
sometimes produced by aircraft
engine exhaust. The combination of
high humidity and low temperatures
that often exists at aircraft cruise
altitudes allows the formation of
contrails. Contrails are composed
primarily of water (in the form of ice
crystals) and do not pose health
risks to humans. Contrails have
been a normal effect of aviation
since its earliest days. Depending
on the temperature and the amount
of moisture in the air at the aircraft
altitude, contrails can either
evaporate quickly or they can persist and grow. Engine exhaust produces only a small portion of
the water that forms ice in persistent contrails. Persistent contrails are mainly composed of
water naturally present along the aircraft flight path.
Aircraft engines emit water vapor, carbon dioxide (CO2), small amounts of nitrogen oxides
(NOx), hydrocarbons, carbon monoxide, sulfur gases, and soot and metal particles formed by
the high-temperature combustion of jet fuel during flight. Of these emittants, only water vapor is
necessary for contrail formation. Sulfur gases are also of potential interest because they lead to
the formation of small particles. Particles suitable for water droplet formation are necessary for
contrail formation. Initial contrail particles, however, can either be already present in the
atmosphere or formed in the exhaust gas. All other engine emissions are considered
nonessential to contrail formation.
For a contrail to form, suitable
conditions must occur immediately
behind a jet engine in the expanding
engine exhaust plume. A contrail will
form if, as the exhaust gases cool
and mix with surrounding air, the
humidity becomes high enough (or,
equivalently, the air temperature
becomes low enough) for liquid
water to condense on particles and
form liquid droplets. If the local air is
cold enough, these newly formed
droplets then freeze and form ice
particles that make up a contrail.
Because the basic processes are
very well understood, contrail formation for a given aircraft flight can be accurately predicted if
atmospheric temperature and humidity conditions are known.
After the initial formation of ice, a
contrail evolves in one of two ways.
If the humidity is low, the contrail will
be short-lived. Newly formed ice
particles will quickly evaporate. The
resulting contrail will extend only a
short distance behind the aircraft. If
the humidity is high, the contrail will
be persistent. Newly formed ice
particles will continue to grow in size
by taking water from the surrounding
atmosphere. The resulting lineshaped
contrail extends for large
distances behind an aircraft.
Persistent contrails can last for
hours while growing to several
kilometers in width and 200 to 400
meters in height. Contrails spread
because of air turbulence created by
the passage of aircraft, differences
in wind speed along the flight track,
and possibly through effects of solar
heating.
Thus, the surrounding atmosphere’s
conditions determine to a large
extent whether or not a contrail will
form after an aircraft’s passage, and
how it evolves. Other factors that
influence contrail formation include
engine fuel efficiency, which affects
the amount of heat and water
emitted in the exhaust plume.
Contrails become visible roughly about a wingspan distance behind the aircraft. Contrails can
be formed by propeller or jet turbine powered aircraft. During WWII, large formations of bombers
left strikingly remarkable contrail formations. Typical contrails are shown below.
The contrails formed by the exhaust at high altitude are typically white and very similar to cirrus
clouds. As the exhaust gases expand and mix with the atmosphere, the contrail diffuses and
spreads. It is very difficult to distinguish aged contrails from cirrus clouds. It is very difficult to
distinguish aged contrails from cirrus clouds. At sunsets, these contrails can be visibly eyecatching
and striking as they reflect the blue, yellow, and red spectrum of the reflected sunlight.
Persistent contrails are of interest to
scientists because they affect the
cloudiness of the atmosphere.
Scientists in the United States,
Europe, and elsewhere have studied
contrail formation, occurrence, and
persistence, and research efforts on
these topics continue. Shown below
is a photo taken from the research
aircraft Falcon of the German
Aerospace Center (Deutsches
Zentrum fh r Luft- und Raumfahrt
(DLR) at about flight level 33,300
feet of an Airbus A340 with contrails
(left) and a Boeing 707 without
contrails (right). This illustrates a
scientific effort to evaluate the
effects of different engine
characteristics on contrail formation

The "Chemtrail" Hoax
A hoax that has been around since 1996 accuses the Air Force of being involved in spraying the
US population with mysterious substances and show various Air Force aircraft "releasing
sprays" or generating unusual contrail patterns. Several authors cite an Air University research
paper titled "Weather as a Force Multiplier: Owning the Weather in 2025"
(http://www.au.af.mil/au/databa...earch/ay1996/acsc/96-025ag.htm) that suggests the Air
Force is conducting weather modification experiments. The purpose of that paper was part of a
thesis to outline a strategy for the use of a future weather modification system to achieve
military objectives and it does not reflect current military policy, practice, or capability.
The Air Force's policy is to observe and forecast the weather. The Air Force is focused on
observing and forecasting the weather so the information can be used to support military
operations. The Air Force is not conducting any weather modification experiments or programs
and has no plans to do so in the future.
The "Chemtrail" hoax has been investigated and refuted by many established and accredited
universities, scientific organizations, and major media publications.
Claims and Facts
Claim: Long-lasting contrails are something new and they have abnormal characteristics.
Fact: Contrails can remain visible for very long periods of time with the lifetime a function of the
temperature, humidity, winds, and aircraft exhaust characteristics. Contrails can form many
shapes as they are dispersed by horizontal and vertical wind shear. Sunlight refracted or
reflected from contrails can produce vibrant and eye-catching colors and patterns. Observation
and scientific analysis of contrails and their duration date back to at least 1953.
Claim: Grid patterns of contrails in the sky are evidence of a systematic spraying operation.
Fact: The National Airspace System of the United States is orientated in an east-west and
north-south grid with aircraft flying at designated 2000 foot increments of elevation. Contrails
formed by aircraft may appear to form a grid as the winds disperse the contrails. More contrails
are seen in recent years due to the growth in the civil aviation market. The FAA is responsible
for the NAS and Air Force aircraft operate under the same rules and procedures as civilian
aircraft when using the NAS.
Claim: There are reported outbreaks of illness after the appearance of "Chemtrails"
Fact: There is no such thing as a "Chemtrail". Contrails are safe and are a natural
phenomenon. They pose no health hazard of any kind. If there are massive outbreaks of
illnesses, your local health department should be able to tell you if it is an abnormal event. Local
health departments generally network together when they start seeing problems. If there is a
problem, the CDC will get involved.
Claim: Samples taken have shown the presence of the "DOD patented" bacteria pseudomonas
fluorescens.
Fact: The bacteria claimed to be DOD developed and patented is actually a common, naturally
occurring bacteria. The U.S. Patent Office (www.uspto.gov) lists 181 patents involving
pseudomonas fluorescens, none of which are held by DOD.

Evo popis zemalja gde se aktivno vrsi zaprasivanje: