Name: Jared
Status: student
Grade: 4-5
Location: CA
Country: N/A
Date: 6/21/2005
Question:
My son Jared ask me these questions after looking
at the flat bottoms of our storm clouds. What determines the lower
altitude of rain cloud? Is there a formula to calculate the bottom
position of the clouds?
Replies:
Replies:
Jared,
The bottom of a cloud occurs at the elevation where the
air becomes saturated with water. This is called the
lifting condensation level. The air is cooled to this point
either by lifting of a layer of air (yielding a stratus cloud
layer) or by a upwards moving convective plume (yielding
individual cumulus clouds).
Equations to determine the bottom of a cloud are beyond the
scope of this web site. However, data from a radiosonde sounding
can be used to determine the height at which the air temperature
in a parcel of air would be cooled to the dew point temperature
(where saturation would occur), as a rough estimate of the height
at which a cloud would occur.
David R. Cook
Atmospheric Physics and Chemistry Section
Environmental Research Division
Argonne National Laboratory
NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.
