Throughout history, the rising and falling waters of the mighty Nile
River have directly impacted the lives of the people who live along
its banks. These images of the area around Sudan's capital city of
Khartoum capture the river's dynamic nature. Acquired by the
Multi-angle Imaging SpectroRadiometer's nadir (vertical-viewing)
camera, they display the extent of the Nile waters before and after
the onset of the rainy seasons of 2000 (top pair) and 2001 (bottom
pair). The images are displayed in "false color", using the camera's
near-infrared, green, and blue bands. With this particular spectral
combination, water appears in shades of blue and turquoise, and highly
vegetated areas show up as bright red.
Originating in Uganda and Ethiopia, respectively, the waters of the
White Nile (western branch) and Blue Nile (eastern branch) converge at
Khartoum (about half-way between image center and the left-hand
side), and continue to flow northward as the Great Nile. Although the
most obvious feature in these images is the increased width of the
White Nile between spring and summer, careful inspection shows that
the Great Nile is at its widest in August 2001 (note in particular
the area between the clouds near the top of this panel). Heavy rains
in the Blue Nile catchment area of the Ethiopian highlands led to a
rapid overflow of the river's floodwaters into the main stream of the
Great Nile, leading to extensive flooding, the worst effects of which
occurred north of Khartoum. According to the Food and Agriculture
Organization of the United Nations, tens of thousands of people have
fled their homes, and the number of people in need of urgent food
assistance in Sudan, estimated at three million earlier in the year,
was likely to increase with the onset of these floods.
South of the confluence of the White Nile and the Blue Nile, the area
of a cross-hatched appearance is the irrigated plain of El Gezira. The
Gezira irrigation scheme uses water from the Makwar Dam (now called
the Sennar Dam), located across the Blue Nile south of Khartoum. Among
the main agricultural products of this region are cotton, millet,
peanuts and fodder crops.
Overall prospects for Sudan's 2001 grain crop were already poor prior
to the flooding due to a late start of the rainy season in parts of
the country. Following two consecutive years of serious drought,
precipitation arrived too late to save the grain harvest that normally
begins in late August. Lower harvests for the past two years coupled
with depletion of stocks have led to a rise in cereal prices, reducing
access to food for the Sudan's poorer citizens, already suffering from
the effects of Africa's longest running civil war.
Each of these images represents an area of about 130 kilometers x 150
kilometers. The data were obtained during Terra orbits 1922, 3553,
7281, and 8912.
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.
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