Cirrus (Ci)

The high cloud par excellence. A cloud genus of frayed appearance and easy identification, made up of a set of separate cloud units, of gleaming white color and shaped like delicate filaments, banks, or narrow bands. The word cirrus is a Latin term meaning strands of hair or a mane, which describes its appearance very well. Cirrus clouds cross the skies between 8 and 12 kilometers of altitude and are entirely made up of ice crystals, which reflect most of the solar radiation striking them, hence their resplendent whiteness. According to the Atlas Internacional de Nubes of the WMO, this cloud genus can present up to five different species (fibratus, uncinus, spissatus, castellanus and floccus) and four varieties (intortus, radiatus, vertebratus and duplicatus).