© Michael Bruhn
Docklands, Melbourne, Victoria, Australia
Latitude: 37° 49' 10'' S
Longitude: 144° 57' 8'' E
04 October 2005 1645 (Local Time)
Camera direction: towards NW
Image P/S code: P.1.13
Image I.D.: 5863
CL = 0, CM = 0, CH = 2
In this photograph we see Cirrus mostly in the form of an extensive, fairly dense, whitish patch of cloud; this identifies it as the species spissatus. When viewed towards the Sun, spissatus appears greyish and may be dense enough to obscure the Sun entirely. Along the top edge of the cloud, the supplementary feature fluctus can be seen. Fluctus is usually a short-lived wave formation, generally found on the top surface of the cloud and in the form of curls or breaking waves. It is also known as “Kelvin-Helmholtz waves”, although it is not especially well developed in this image.
Links in the image description will highlight features on the image. Mouse over the features for more detail.
The 0000 UTC Melbourne Airport, Victoria, Australia (WMO 94866) sounding shows a low-level inversion at 900 hPa. Between 900 and 340 hPa, the atmosphere is very dry. At 340 hPa (about 8 600 m), we see high-level moisture to the tropopause. 8 600 m is the likely height of the Cirrus cloud in the image.