Message-Id: <v01540b00b17506262944@[204.188.208.63]>
Date: Tue, 5 May 1998 11:50:58 -0800
To: "Pinhole Listserv" <pinhole@exploratorium.edu>
From: pwilding@marin.k12.ca.us (Peter Wilding)
Subject: Re: Pinhole Daily Digest
Rob,
Re : Cumulonimbus cloud bases.
The flat bottom of cumulonimbus clouds is the altitude at which the air
parcel that is rising to produce the cloud, first reaches its condensation
temperature, the dew point for that particular air. The air is rising over
a significant area and so produces an extensive flat bottomed cloud.
Clear air turbulence is often associated with jet stream activity at high
altitude. High speed jets develop shearing effects relative to the slower
moving air all around the core. This can produce the variable wind speed
directions which make feeding time on jets at cruising altitude so
entertaining.
Peter Wilding.
- Every Science --- Peter Wilding -- California SS&C --
- Every Student --- pwilding@marin.k12.ca.us --
- Every Year Home fax and phone 415 892 3054--
- Coordinated Science Series - Cambridge University Press--