Cirrus Clouds (Ci)

Four images of the "clamp-like" Cirrus uncinus clouds are shown here. The uncinus cloud in CiUncinus1.jpg arose above an Altocumulus layer. The "clamps" are generated by ice particles which sediment from the cloud into a slowly moving air layer below. The particles that have declined most stay farthest behind the cloud.

In CiUncinus1.jpg the upper Cirrus cloud has almost been already dissolved so that nearly only the clamps can be noticed. A widely spread Cirrus stratus layer is pictured in CiUncinus2.jpg. In CiUncinus3.jpg and CiUncinus4.jpg the ice-crystals fall vertically top down at first, before they get into an air layer with large wind velocity.

CiUncinus1.jpg: S. Borrmann, Ingelheim, Germany, July 2001

CiUncinus2.jpg: S. Borrmann, Frankfurt Airport, on the ground, 17 December, 2:34:41 p.m.

CiUncinus3+4.jpg : S. Borrmann, Ingelheim, Germany, 21 June 2005,
7:44 a.m.