Infra-red Satellite Images of
the 1999 Cosmonaut Sea Polynya
Here are examples of infra-red
satellite images of the Cosmonaut Sea. The images are from an
instrument called the Advanced Very High Resolution Radiometer
(AVHRR) that flies on the NOAA family of polar orbiting satellites.
The AVHRR collects visible and infra-red radiation reflected (in
the case of visible radiation) and emitted (in the case of infra-red
radiation) from the earth's surface and/or clouds. The nomimal
resolution of AVHRR imagery is 1 km by 1km.
On this site we present
both full resolution imagery, as collected by the NOAA-15 satellite,
as well as imagery subsampled to a horizontal resolution of 4
km by 4km as collected by the NOAA-14 satellite. The scale of
the features that are of intersest shows up best in the high resolution
NOAA 15 imagery.
Infra-red imagery provides
one with information about the temperature at which the various
objects in the scene are radiating at. The imagery was obtained from NOAA's
Satellite Active Archive (SAA) and processed with Seaspace's
Terascan software.
The imagery has been processed so
that cold surfaces appear white while warm surfaces appear black.
Hence the Antractic land mass shows
up as being white, Sea Ice, which is warmer than the land mass,
has a mottled grey appearance. Depending
on their height, clouds are either white or gray. Open water,
which is the warmest surface
in the scenes, appears black.
Superimposed on the images
is the 50% sea ice concentration isoline as determined from passive
microwave satellite data.