Ci compared with Ac

(Section 2.3.1.6.3)

Cirrus is distinguished from Altocumulus by:

• Mainly fibrous or silky appearance
• Absence of cloud elements in the form of laminae, rolls, etc
• Usual absence of any shading and only partial shading in the species spissatus
• Absence of undulations
• Absence of virga
• Absence of a corona