Clear Air Turbulence
Clear-air turbulence (CAT) is the turbulent movement of air masses in the absence of any visual cues such as clouds, and is caused when bodies of air moving at widely different speeds meet.
The atmospheric region most susceptible to CAT is the high troposphere at altitudes of around 7,000–12,000 metres (23,000–39,000 ft) as it meets the tropopause. Here CAT is most frequently encountered in the regions of jet streams. At lower altitudes it may also occur near mountain ranges. Thin cirrus cloud can also indicate high probability of CAT.
CAT can be hazardous to the comfort, and even safety, of air travel.
Read more about Clear Air Turbulence: Detection, Factors That Increase CAT Probability, Effects On Aircraft
Famous quotes containing the words clear, air and/or turbulence:
“When I’m carried away, isn’t it clear that my heart contradicts my mouth?”
—Jean Racine (1639–1699)
“Then, that no region of the universe
Should remain void of life, the floor of heaven
Was peopled with the stars and godlike forms,
The seas became the abode of glittering fish.
Earth took the beasts and mobile air the birds.
A holier animal was wanting.”
—Ovid (Publius Ovidius Naso)
“their eyes still fixed, hoping to find once more,
Being by Calvary’s turbulence unsatisfied,
The uncontrollable mystery on the bestial floor.”
—William Butler Yeats (1865–1939)