Cumulonimbus Clouds (Cb)

Different scenes are displayed here, where the convective vertical momentum of upwards moving Cumulonimbus clouds was sufficient enough in order to penetrate the layers of Cirrus clouds above. The cruising altitude was 11300 m and the surrounding temperature was -54 °C. Penetration1.jpg to Penetration4.jpg shows a Cumulonimbus calvus cloud, which shows no signs of icing yet. Taking a hasty look at Penetration4.jpg one could recognize a pileus by mistake. The sequence Penetration5.jpg to Penetration15.jpg was taken quickly one after another and shows detailed views of a Cb penetrating a thin Cirrus veil.

In this case it was necessary to observe the cloud for a while to be sure that it is not a pileus, but an already existing, extremely thin Cirrus layer. This one was lifted by the Cb convection at first and was finally penetrated. Penetration16.jpg and Penetration17.jpg display how the major tower of a Cumulonimbus incus cloud penetrates the Cirrus shield. Shear winds occur above the ambos which transport the upper part of the swelling Cb to the left. Similar penetrations can be found in chapter Cumulus penetrating.

Penetration1-17.jpg: S. Borrmann, flight Varig RG2375 from Fortaleza to Sao Paulo in Brazil, 2 March 2004, between 5:15 p.m. and 5:35 p.m.

Camera Parameters

Olympus E-1 SLR with a 14-54 mm objective. Exposure and selectivity choice (100 ASA) was performed by the camera. The images were taken in the sRGB colour range with a resolution of 2560 x 1920 Pixel x 24 colours.