Description Cirrocumulus and differences with similar clouds
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Cirrocumulus
Thin, white patch, sheet or layer of cloud without shading, composed of very small elements in the form of grains, ripples, etc., merged or separate, and more or less regularly arranged; most of the elements have an apparent width of less than one degree.


Main differences between Cirrocumulus and similar clouds of other genera
(a) Cirrus and Cirrostratus
Cirrocumulus in rounded tufts or in the form of small rounded turrets rising from a common base may be confused with Cirrus presenting a similar appearance. The distinguishing criterion is that the Cirrocumulus tufts or turrets, in contrast with those of Cirrus, have an apparent width of less than one degree, when observed at an angle of more than 30 degrees above the horizon. A sheet of Cirrocumulus differs from Cirrus and Cirrostratus in that it is rippled or subdivided into very small cloudlets; it may include fibrous, silky or smooth portions (characteristic of Cirrus and Cirrostratus ) which, however, do not collectively constitute its greater part.

(b) Altocumulus
Cirrocumulus differs from Altocumulus in that most of its elements are very small (by definition, of an apparent width less than one degree when observed at an angle of more than 30 degrees above the horizon) and without shading.