[DOC] [TLE] Contrail - Wikipedia [PAR] Contrails or vapor trails are line-shaped clouds sometimes produced by aircraft 
engine exhaust, typically at aircraft cruise altitudes several miles above the 
Earth's surface. Contrails are composed primarily of water, in the form of ice 
crystals. ... They can also form closer to the ground when the air is very cold and 
has enough... [DOC] [TLE] Why do some planes leave long trails, but others don't?  Contrail ... [PAR] Mar 5, 2010 ... When the air is wet and cold enough the trails can stay around for a long ... 
Seemingly clear air also contains exactly the same kind of variation in layers. ..... 
Above the level clouds form (I call this wet) ...... Many people make it sound as if 
it's just water vapour that comes out the jet engine and the contrails... [DOC] [TLE] Why do jets leave a white trail in the sky? - Scientific American [PAR] Jets leave white trails, or contrails, in their wakes for the same reason you can ... 
The water vapor contained in the jet exhaust condenses and may freeze, and this 
... forms a cloud very similar to the one your hot breath makes on a cold day. Jet 
... a sign of fair weather, whereas a thick, long-lasting contrail reflects humid air at
... [DOC] [TLE] White Lines in the Sky: A Conspiracy? - SkyManBob.com [PAR] Mar 10, 2009 ... Nor does one appear when it's low. ... This is a contrail, a short white line behind 
the jet's engines. ... If the air mass is very humid, the exhaust's soot particles enter 
the ... like cloud seeding  to produce a thicker contrail as surrounding .... of cold 
air were true, planes would also leave behind these trails. [DOC] [TLE] vapour trail | aerology | Britannica.com [PAR] Vapour trail, also called Condensation Trail, orContrail, streamer of cloud 
sometimes observed behind an airplane flying in clear, cold, humid air. ... be 
distorted by the winds, and sometimes it spreads outwards to form a layer of 
cirrus cloud. ... Meteorology entails the systematic study of weather and its 
causes, and provides. [DOC] [TLE] Condensation trail - definition and synonims of condensation trail ... [PAR] Like all clouds, contrails are made of water, in the form of a suspension of billions 
of .... Its implementation is based on analysing how often the term condensation 
... is frequently observed behind aircraft flying in clear, cold, humid air: the moving 
... Vapour trail, also called Condensation Trail, or Contrail, is a stream of cloud... [DOC] [TLE] Student Resource Glossary [PAR] Absolute humidity, The mass of water vapor in a given volume of air. ... moist air 
moves over a cold surface and the air cools to below its dew point. ... 
Condensation nuclei, Also called cloud condensation nuclei. ... Contrail (
condensation trail), A cloudlike streamer frequently seen forming behind aircraft 
flying in clear, cold,... [DOC] [TLE] Conspiracy Theories: What are those planes that leave thick white ... [PAR] An engine (jet or propeller) burns hydrocarbon fuel (gasoline or kerosene), which 
combines ... If it's too warm, too cold, too dry or too wet, the contrails don't form. ... 
Many people say things like vaccines and airplane vapor trails are part of .... 
Which planes fly at a very high altitude and leave stream of cloud behind? Are 
they... [DOC] [TLE] How are 'contrails' made by airplanes? - Page 1 - RunRyder [PAR] The condensation trail left behind jet aircrafts are called contrails. ... in relation to 
the other factors in the air that cause visible moisture like a cloud or fog. ... Just a 
longggg stream of ice. ... condensation trail(Or contrail; also called vapor trail.) 
... observed to form behind aircraft flying in clear, cold, humid air. [DOC] [TLE] c [PAR] Atmospheric conditions devoid of wind or any other air motion. ... A weak low 
pressure circulation that may form off the Southern California coast. ... It is also 
the least common cloud type, often

Question: Also called a vapor trail, it's a cloud-like streamer that forms behind jets in clear, cold, humid air
Answer: Contrail