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Northern Italy
The
image represents the region of Alessandria, Piemonte. The Tanaro river flows
from the left to the upper part of the image; near the top, just before the
confluence with the Bormida river, lies the city of Alessandria, identifiable
by yellow bright points. The other small pointed areas in yellow are other villages,
while the two dark "stripes" crossing themself left to Alessandria
are highways.
The colours in the image are achieved by merging an image of the 9th of November
1994 (assigned to the red chanel), one of the 4th of October 1994 (green), and
an artificial channel (blue) which is the second principal component of the
two scenes. This allows the visualization also small changes between the two
acquisition dates.
The most significant changes are marked in cyan and show the flooded areas mainly
located along the Tanaro river, representing a total surface within the image
of 15,7 km2. A small lake on the upper left side of the city of Alessandria
is imaged as a darker, blue patch, revealing that no changes occurred between
the two dates. The other colours are only due to a much higher humidity on the
9 November respect to the 4 October: orange-red are bare soil, green are meadows
and yellow settlements and orchyards (wineyards, etc.).
(Earth Watching Team/Eurimage, Rome)
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,
atmospheric chemistry
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