Cirriform rotor cloud observed on a Canadian Arctic ice cap

ABSTRACT

A thin rotor cloud was observed on the lee side of Penny Ice Cap in the Canadian Arctic on 21 April 1996. The cloud consisted of thin cirriform layers, so that its motion was clearly observed. By means of time-lapse camera photography, the velocity of the cloud rotation was estimated to be around 2 m s^sup -1^. It is suggested that the existence of a high humidity layer at the bottom of an inversion layer is a key factor for the formation of the thin rotor cloud.

A rotor cloud, a rolling cloud driven by wind, was observed on an ice cap in the Canadian Arctic. As a…