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Red River (USA & Canada), April 1997
In the second half of april the regions of North Dakota (USA)
and Manitoba (Canada) had some of the worst flooding
in their history, with severe damage to the towns and farmland over
very large areas. The Red River Valley is subject to frequent
flooding due to spring runoff of melting snow, but it is rarely
so extensive. The flood was the largest flood in the region this
century due to the double quantity of snow during the winter and
a major snowstorm in early April. The flood reached its peak at
the US-Canadian border around April 26, but continued to increase
further north along the Red River Valley. A new lake formed in
Canada (centred at Morris, near the town of Winnipeg, Manitoba)
which reached a width of 50 km and over 100 km in length.
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ERS-2 SAR Mosaic
This image is obtained by mosaicking ten
ERS-2 SAR images of four (two for each track) different
acquisitions (one before the flooding and one during)
along the Red River. The image is georeferenced to the
north and shows the eastern part of North Dakota, part of
the western Minnesota (the Red River is the State
boundary) and (at the top of the image) the southern part
of Canada. The flooded areas appear in dark Blue and are
located mainly below the river. The town of Fargo, badly
hit by the waters, lies below the flooded area at the
lower part of the image (clearly evident in the high
resolution image).
The town of Grand Forks is located
at the bottom of the flooded area visible in the upper
left corner of the right track image.
Within both higher resolution images rectangular
fields are clearly shown, with different brightness
according to the different crops. The highways and major
communication links appear as darker lines.
Click the image to see two higher resolution
versions from each subsequent image two further zooms are
possible:
(Left track 366 * 553 pixels, 105 Kb JPEG)
(Right track 588 * 1070 pixels, 227 Kb JPEG)
Image area coverage: 250 x 500 Km
Technical information about the image:
- Satellite / Sensor: ERS-2 SAR
- Acquisition date: 25 April 1997
- Orbit: 10530 - Frames 2637, 2655, 2673
- Acquired by: Gatineau (Canada)
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NOAA AVHRR images during flooding |
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19 April day pass band 3 In this image
the fire in the town of Grand Forks is also visible.
Darker areas represent flooding.
Click on the thumbnail to see the full image:
(278 * 459 pixels, 15 Kb JPEG)
Image area coverage: 150 x 300 Km
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19 April day pass band 4 (brightness
temperature) Same acquisition of the previous image,
but with a different band and on all the river extension.
Black areas are clouds (cold).
Click on the thumbnail to see the full image:
(278 * 754 pixels, 40 Kb JPEG)
Image area coverage: 150 x 500 Km
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22 April day pass band 4 (brightness
temperature) On the 22 the flood extension on the
upper part of the image is increased. Black areas are
clouds (cold).
Click on the thumbnail to see the full image:
(278 * 577 pixels, 40 Kb JPEG)
Image area coverage: 150 x 400Km
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24 April night pass band 4 (brightness
temperature) In this nightime image the flooding is
quite evident because warmer than the land. The flooding
appears brighter.
Click on the thumbnail to see the full image:
(278 * 730 pixels, 32 Kb JPEG)
Image area coverage: 150 x 500 Km
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Print version