Saturday, November 17, 2012
Wasaga Beach Condensation Trails
Contrails form through the injection of water vapor into the atmosphere by exhaust fumes from a jet engine. If the surrounding air is cold enough, a state of saturation is attained and ice crystals develop, producing a contrail.
If the air in which the contrail develops has a low relative humidity, the cloud particles will quickly evaporate. Even in the presence of higher relative humidities, upper-level winds can spread a contrail apart to produce a horizontal sheet-like cloud. For a contrail to remain in tact for a long period of time, the air must have a high relative humidity in the presence of relatively light winds.