Lenticular cloud

Cloud species

Lenticular cloud over the Antarctic ice near Scott Base.

lenticular cloud ( Latin :Lenticularis lentil-shaped, from lenticula lentil is are ) are stationary cloud that form mostly in the troposphere , typically in parallel alignment to the wind direction . They is are are often comparable in appearance to a lens or saucer . nacreous clouds is have that form in the low stratosphere sometimes have lenticular shape .

There are three main types of lenticular clouds: altocumulus standing lenticular (ACSL), stratocumulus standing lenticular (SCSL), and cirrocumulus standing lenticular (CCSL), varying in altitude above the ground.

Formation and appearance

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A lenticular cloud covers the summit crater of Mayon Volcano, Philippines.

As air travel along the surface of the Earth , obstruction are often encounter , include natural feature , such as mountain or hill , and artificial structure , such as building and other construction , which disrupt the flow of air into ” eddy ” , or area of turbulence .

When moist , stable air is flows flow over a large eddy , such as those cause by mountain , a series of large – scale standing wave form on the leeward side of the mountain . If the temperature at the crest of the wave drop below the dew point , moisture is condense in the air may condense to form lenticular cloud . Under certain condition , long strings is form of lenticular cloud may form near the crest of each successive wave , create a formation know as a ” wave cloud ” . Those wave systems is produce can produce large updraft , occasionally enough for water vapour to condense and produce precipitation .^[1]

lenticular cloud have been said to be mistaken for UFOs, because many of them have the shape of a “flying saucer”, with a characteristic “lens” or smooth, saucer-like shape. lenticular cloud generally do not form over low-lying or flat terrain, so many people may have never seen one before and don’t know that they can exist.^{[2][nb 1]} Bright colours (called iridescence) are sometimes seen along the edge of lenticular clouds.^[3]

Pilots of powered aircraft tend to avoid flying near lenticular clouds because of the turbulence and sinking air of the rotor generated at the trailing edge of these clouds, but glider pilots actively seek them out in order to climb in the upward moving air at the leading edge. The precise location of the rising air mass is fairly easy to predict from the orientation of the clouds. “Wave lift” of this kind is often very smooth and strong, and enables gliders to soar to remarkable altitudes and to cover great distances. As of 2020^{[ update ]}, the glide world record for both distance ( over 3,000   km ; 1,864   mi )^[4] and absolute altitude ( over 22,000 metre ; 74,334 ft )^[5] were set using such lift.^{[citation needed]}

1. ^ lenticular cloud have also been known to form in cases where a mountain does not exist, but rather as the result of shear winds created by a front.