Cumulonimbus Clouds (Cb)

Scheme.jpg: Large Cumulonimbus clouds below the lower cloud limit are surrounded by a zone where warm air is drawn from the neighbourhood into the cloud and then transported upwards. During ascent the air parcel experiences adiabatic expansion with associated cooling. If this air parcel is sufficiently humid cloud droplets are generated. Hence the released latent heat induces additional warming and thus enhances the convection.

On the left hand side of the photo-graphs a part of a large Cumulonimbus can be recognized. The anvil was located directly above the photographer. Looking closely at it a hazy zone with "stripes" can be noticed below the cloud. The "stripes" mark the areas where the surrounding air enters the cloud. Therefore the "stripes" visualize the way of the streamlines of the inflowing air.

CbInflow1-9.jpg: F. Stroh (Research Center Juelich GmbH), S. Borrmann, Darwin, Northern Territory, Australia, SCOUT-O3 field campaign, 23 November 2005, 6:03 to 6:06 p.m. local time