The shape and size of cellular patterns within marine stratocumulus
cloud layers can change dramatically with the prevailing meteorological
conditions. These views from the Multi-angle Imaging SpectroRadiometer
provide an example of very large scale closed cells, and can be
contrasted with the small cells described in an earlier image release.
As described in that release, cellular structures are associated with
the sinking of air that is strongly cooled at the level of the cloud-tops.
This type of scene is fairly typical of mid-latitude oceanic clouds
unperturbed by cyclonic or frontal activity.
When the cell centers are cloudy and the main sinking motion is
concentrated at cell boundaries, the cells are referred to as "closed".
The cell diameters in this image range from 40 to 100 kilometers
(about twice the average size of closed cells in general) and show
an increased brightness at the cell centers, giving them a mogul-like
appearance. Because the cloud-top heights do not vary substantially
across the cells, the distinctive appearance is more likely due to
an increased concentration of cloud droplets at their centers.
The left-hand panel shows a part of the swath captured by MISR's
nadir (vertical-viewing) camera on November 25, 2001 (Terra orbit 10318)
and is displayed at a resolution of 1.1 kilometers per pixel. The
right-hand panel highlights part of this scene at a resolution
of 275 meters, and is centered at approximately 49.2 degrees south
latitude and 179.9 degrees east longitude, covering an area of about
233 kilometers x 240 kilometers. The images utilize data from blocks
123 to 135 within World Reference System-2 path 68.
MISR was built and is managed by NASA's Jet Propulsion Laboratory,
Pasadena, CA, for NASA's Office of Earth Science, Washington, DC.
The Terra satellite is managed by NASA's Goddard Space Flight Center,
Greenbelt, MD. JPL is a division of the California Institute of
Technology.
Image credit: NASA/GSFC/LaRC/JPL, MISR Team.L, MISR Team.
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