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Floods in Southern Africa
| Title |
Floods in Southern Africa |
| Description |
A black web of water surrounds the Zambezi River in the top image, captured by the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite on February 10, 2007. Mozambique was experiencing its worst floods in six years when the Zambezi flowed over its banks in January and February 2007, reported the United Nations Office for the Coordination of Humanitarian Affairs (OCHA [ http://www.reliefweb.int/rw/RWB.NSF/db900SID/YZHG-6YCQR4?OpenDocument&rc=1&emid=FL-2007-000011-ZMB ]). As of February 12, an estimated 29 people had died and 60,000 had been evacuated from the river's banks. Early and heavy rains fell over the entire Zambezi Basin, pushing the Zambezi and many of its tributaries into flood stage. The floods are likely to worsen as the 2,574-kilometer-long river receives water from its swollen tributaries in Angola, Namibia, Zambia, and Malawi. Releases from the massive Cahora Bassa Reservoir, [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14110 ] which is reaching its capacity, are also expected to make flooding worse along the lower Zambezi. These images show the lower Zambezi where it meets the Shire River flowing south from Malawi, one of the most severely affected regions in Mozambique. The top image provides a remarkably cloud-free view of the floods, while the lower image, taken on December 31, 2006, shows the region before the rains started in January. The images were made with a combination of infrared and visible light to highlight the presence of water on the ground. Water is black or dark blue, while plant-covered land is green. Bare earth is tan and pink, and clouds are pale blue and white. Fires are outlined in red. Images such as these and photo-like, true-color images are provided by the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?FAS_SMozambique/2007041 ] on a daily basis. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Floods in Southern Africa
| Title |
Floods in Southern Africa |
| Description |
A black web of water surrounds the Zambezi River in the top image, captured by the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite on February 10, 2007. Mozambique was experiencing its worst floods in six years when the Zambezi flowed over its banks in January and February 2007, reported the United Nations Office for the Coordination of Humanitarian Affairs (OCHA [ http://www.reliefweb.int/rw/RWB.NSF/db900SID/YZHG-6YCQR4?OpenDocument&rc=1&emid=FL-2007-000011-ZMB ]). As of February 12, an estimated 29 people had died and 60,000 had been evacuated from the river's banks. Early and heavy rains fell over the entire Zambezi Basin, pushing the Zambezi and many of its tributaries into flood stage. The floods are likely to worsen as the 2,574-kilometer-long river receives water from its swollen tributaries in Angola, Namibia, Zambia, and Malawi. Releases from the massive Cahora Bassa Reservoir, [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14110 ] which is reaching its capacity, are also expected to make flooding worse along the lower Zambezi. These images show the lower Zambezi where it meets the Shire River flowing south from Malawi, one of the most severely affected regions in Mozambique. The top image provides a remarkably cloud-free view of the floods, while the lower image, taken on December 31, 2006, shows the region before the rains started in January. The images were made with a combination of infrared and visible light to highlight the presence of water on the ground. Water is black or dark blue, while plant-covered land is green. Bare earth is tan and pink, and clouds are pale blue and white. Fires are outlined in red. Images such as these and photo-like, true-color images are provided by the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?FAS_SMozambique/2007041 ] on a daily basis. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Dust Plumes off Namibia
| Title |
Dust Plumes off Namibia |
| Description |
Many plumes of desert dust (tan pixels) were streaming westward off the coasts of Angola (top) and Namibia (bottom) in southwestern Africa on June 9, 2004. Notice the dark green color of the ocean beneath the dust plumes, indicating the presence phytoplankton thriving in the surface waters there. The frequent influx of iron-rich desert dust settling into the ocean here?together with cold, nutrient-rich waters upwelling from the depths?make these some of the most biologically productive ocean waters on Earth. This true-color image was acquired on June 9, 2004, by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA?s Terra satellite. The high-resolution image available here is 500 meters per pixel, but the image is also available at additional resolutions. [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2004161-0609/Namibia.A2004161.0930 ] Image courtesy Jacques Descloitres, MODIS Rapid Response Team, NASA-Goddard Space Flight Center |
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Dust Plumes off Namibia
| Title |
Dust Plumes off Namibia |
| Description |
Whisps of white dust sweep off of northern Namibia?s Skeleton Coast in this Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) image, acquired on June 9, 2004 by NASA?s Terra [ http://terra.nasa.gov/ ] satellite. The image has been draped over data from the Shuttle Radar Topography Mission [ http://www2.jpl.nasa.gov/srtm/ ] to show changes in elevation. The resulting 3-D image could help pinpoint the source of blowing dust, though in this image, the source is not entirely clear. In the lower right corner are the peaks of the Kaokoveld Mountains. The view of the coast shown here is similar to one a person might have standing (or flying) over Namibia's northern border looking south-southwest. Image by Frank Eckardt, Department of Environmental Science, University of Botswana, based on data from the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC and SRTM data courtesy NASA/JPL/NIMA/USGS, SRTM [ http://www2.jpl.nasa.gov/srtm/ ] Science Team. |
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Dust Plumes off Namibia
| Title |
Dust Plumes off Namibia |
| Description |
Whisps of white dust sweep off of northern Namibia?s Skeleton Coast in this Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) image, acquired on June 9, 2004 by NASA?s Terra [ http://terra.nasa.gov/ ] satellite. The image has been draped over data from the Shuttle Radar Topography Mission [ http://www2.jpl.nasa.gov/srtm/ ] to show changes in elevation. The resulting 3-D image could help pinpoint the source of blowing dust, though in this image, the source is not entirely clear. In the lower right corner are the peaks of the Kaokoveld Mountains. The view of the coast shown here is similar to one a person might have standing (or flying) over Namibia's northern border looking south-southwest. Image by Frank Eckardt, Department of Environmental Science, University of Botswana, based on data from the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC and SRTM data courtesy NASA/JPL/NIMA/USGS, SRTM [ http://www2.jpl.nasa.gov/srtm/ ] Science Team. |
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Hydrogen Sulfide Eruption Al
…
| Title |
Hydrogen Sulfide Eruption Along the Coast of Namibia |
| Description |
A milky green cloud of water off the Namib Desert coast of Namibia in southern Africa is a tell-tale sign of sulfur rising to the surface. The yellowish clouds of sulfur come from hydrogen sulfide gas produced by anaerobic bacteria (bacteria that can live without oxygen) at the ocean floor. In this region, strong currents bring abundant food from the bottom of the ocean to nurture large plant and animal populations. As the surface life dies, it sinks to the bottom of the ocean, where it becomes food for anaerobic bacteria.. The bacteria release hydrogen sulfide gas, which produces pure sulfur when it reacts with oxygen near the surface. In the first stages of the reaction, the sulfur appears white, and in this image creates a milky-green green tinge to the water. When the transformation is more complete, the yellowish sulfur and the blue water will combine to make the plume appear very green. The hydrogen sulfide gas is highly toxic to fish. Periodic die-offs of whole populations of fish and other commercial seafood are ongoing concerns for the regional fishing industry. This true-color Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) image was acquired by the Terra [ http://terra.nasa.gov/ ] satellite on March 5, 2004. The diagonal stripes that run across the image mark the beginning and end of the rotation of MODIS' double-sided scan mirror. The scan lines are caused by small differences between the two sides of the scan mirror. The high-resolution image provided above is at MODIS? maximum resolution of 250 meters per pixel. The image is available in additional resolutions [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2004065-0305/Namibia.A2004065.0930 ]. Image courtesy Jacques Descloitres, MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC |
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Hydrogen Sulfide Eruption Al
…
| Title |
Hydrogen Sulfide Eruption Along the Coast of Namibia |
| Description |
*Hydrogen Sulfide Eruption Along the Coast of Namibia* Bright colors in the ocean waters off the coast of Namibia tell a story of marine life and death. In this region of the South Atlantic, winds push the warm surface water westward, and cold waters from the bottom of the ocean rush up in their place. The cold water carries with it the nutrients that have sunk to the ocean floor, providing a boon to ocean life. In particular, microscopic plants called phytoplankton thrive on the added nutrients. In turn, these tiny plants are a source of food for many other ocean dwellers. In this Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) image acquired on April 10, 2004, by the Terra [ http://terra.nasa.gov/ ] satellite, a dark green swirl of water in the ocean shows where a colony of phytoplankton bloom. The individual plants grow quickly, then die after a few days. Their remains sink to the ocean floor where bottom-dwelling bacteria break them down. Eventually, the bacteria use all of the oxygen, and a second form of bacteria take over. These bacteria, anaerobic bacteria, release toxic hydrogen sulfide gas as they consume the decomposing plants. The gas rises to the surface along the Namibian coast, where it turns to pure sulfur in reaction to oxygen in the water. The yellow sulfur tints the blue water a bright green in this satellite image. Called hydrogen sulfide eruptions, the phenomenon has only been observed along the Namibian coast. Sadly, the decomposing plants are lethal to the life they once supported. Hydrogen sulfide gas can kill large populations of fish and other marine life. As a result, the waters off the coast of Namibia are closely monitored by the regional fishing and aquaculture industry. Image courtesy Jacques Descloitres, MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC |
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Hydrogen Sulfide Eruptions a
…
| Title |
Hydrogen Sulfide Eruptions along the Coast of Namibia |
| Description |
On April 18, 2004, the Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) on the Aqua [ http://aqua.nasa.gov/ ] satellite detected several bright green hydrogen sulfide eruptions along the coast of Namibia. The eruptions, which are deadly to fish, occur when bacteria release hydrogen sulfide gas as they break down dead plants and animals that have sunk to the sea floor. As the gas rises to the surface, it interacts with oxygen to form solid white sulfur, which tints the water the bright green color seen here. Hydrogen sulfide eruptions happen frequently off the shore of Namibia because of patterns in the ocean currents called upwelling. In this region, cold water pushes nutrients from the ocean floor to the surface, where ocean life thrives. In particular, large colonies of microscopic ocean plants, phytoplankton, grow in the nutrient rich water, forming the dark green swirls seen in this image. As the plants use all of the nutrients, they die and sink to the sea floor where bacteria consume them. The bacteria release toxic hydrogen sulfide gas into the soil. Eventually, the toxic gas erupts from the soil. In addition to the bright waters seen by satellites, the event is marked by massive fish die-offs and a strong smell that resembles rotten eggs. To date, hydrogen sulfide eruptions have only been observed off the shore of Namibia. Additional eruptions can be seen further down the coast at 250 meters per pixel in the high-resolution image provided above. The image is also available in additional resolutions [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2004109-0418/Namibia.A2004109.1235 ]. The MODIS instrument on the Terra [ http://terra.nasa.gov/ ] satellite captured an earlier phase of the eruption on April 17, 2004 [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2004108-0417/Namibia.A2004108.0915 ]. Image courtesy Jacques Descloitres, MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC |
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Hydrogen Sulfide Eruptions A
…
| Title |
Hydrogen Sulfide Eruptions Along the Coast of Namibia |
| Description |
People living along Namibia?s desert coast have long been familiar with the rotten egg smell that periodically emanates from the Atlantic Ocean. With an economy that is largely based on fishing, the locals are also used to seeing millions of fish die whenever the unpleasant scent fills the air. The smell and the fish die-off are caused by hydrogen sulfide erupting from decaying plants on the sea floor. In the southeast Atlantic Ocean, strong ocean currents carry nutrient-rich deep-ocean water to the surface. The waters nourish free-floating microscopic plants, called phytoplankton, and other sea life. When the plants die, they sink to the ocean floor where bacteria begin to break them down. The oxygen is quickly used in the decay process, and anaerobic bacteria take over. These bacteria emit hydrogen sulfide gas as a by-product. The gas builds on the ocean floor until it erupts suddenly. When it reaches the surface, the hydrogen combines with oxygen to form water, allowing solid white sulfur to precipitate into the ocean. Of itself, hydrogen sulfide gas is toxic to fish, but this reaction with oxygen also creates deadly low-oxygen conditions in the ocean. The reaction at the surface also makes hydrogen sulfide eruptions visible in satellite imagery. The white sulfur reflects light, tinting the water bright green along the Namibian coast. On May 12, 2004, the Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) on NASA?s Terra [ http://terra.nasa.gov/ ] satellite captured this image of a hydrogen sulfide eruption in progress. Along the coast, milky green sections of ocean show where hydrogen sulfide gas is coming up. Offshore, a phytoplankton bloom forms a bright green swirl in the ocean water, proof of the productivity that triggers the deadly eruptions. Both the image above and the full image are at MODIS? maximum resolution of 250 meters per pixel. The image is available in additional resolutions [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2004133-0512/Namibia.A2004133.0905 ]. NASA GSFC image courtesy Jacques Descloitres, MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] |
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Fires in Central and Souther
…
| Title |
Fires in Central and Southern Africa |
| Description |
The southern Africa burning season is still underway as farmers and ranchers light fires to clear fields for planting and to renew rangeland vegetation. Numerous fires (red dots) were detected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA?s Terra satellite through Angola (top left quadrant) and Zambia (top right quadrant) and tapering off in Namibia (bottom left quadrant) and Botswana (bottom right quadrant). The green broomstick-shaped feature south of image center is the vegetation of the Okavango River Delta. The highly reflective area to its southeast is the Makgadikgadi Salt Pans. Another salt flat, called Etosha Pan, is visible south of the Angola-Namibia border. This image was acquired on September 12, 2002. Image by Jesse Allen, based on data from the MODIS Rapid Response Team at NASA-GSFC |
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Seasonal floods along the Za
…
| Title |
Seasonal floods along the Zambezi River |
| Description |
Officials in Namibia worked quickly to evacuate more people in the southern Caprivi Strip as a second wave of flooding on the Zambezi River pushed south toward Lake Liambezi. The lake has been dry since 1985, and the flood waters are expected to spread quickly as the lake fills. The Caprivi Strip began to flood in early February, far earlier than the typical rainy season floods. This year?s floods have affected some 50,000 people and are being called the worst floods the region has seen since 1958. The Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) on the Terra [ http://terra.nasa.gov/ ] satellite acquired this image on April 17, 2004. At 250 meters per pixel, the image shows how wide-spread the black flood waters are against the tan and green land. In places, the dark channel of the Zambezi River can be seen as a thin line cutting diagonally across the flood plain. Image courtesy Jesse Allen, based on data from the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC |
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Seasonal floods along the Za
…
| Title |
Seasonal floods along the Zambezi River |
| Description |
On April 12, 2004, the clouds that typically shroud Western Zambia this time of year cleared long enough to give the Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) on the Terra [ http://terra.nasa.gov/ ] satellite this clear view of the flooded Zambezi River. The river floods during the rainy season every year, but this year, the waters are higher than usual. Recent news reports say that 21,000 households in Western and Northwestern Zambia have been affected by the Zambezi floods so far. The flooding began in December 2003, and increased as the region received far more rain than normal. Now the river is covering most of the plains that line its banks, limiting access to the schools and health centers that are not submerged. Fields of maize and rice have also been covered by the floods. The high waters on this stretch of the Zambezi are also troubling to the already water-logged communities downstream. As these flood waters have moved down into northeast Namibia?s Caprivi Strip, they have affected 20,000 people, killing six. Now officials expect the river to continue to expand in the coming weeks. This image shows the Zambezi River in Zambia just north of the Namibian border. Flowing down across the lower left corner of the image is the Cuando River, which also appears to be flooded with black water surrounding the green lines that mark the river?s usual banks. This section of the Cuando River runs along the border of Zambia and Angola. In this false color image, water is black, and vegetation is bright green. A few white and light blue clouds skirt the edges of the scene. The high-resolution image provided above is at MODIS? maximum resolution of 250 meters per pixel. Image courtesy Jesse Allen, based on data from the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC |
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Sulfur Plume Off Namibia
| Title |
Sulfur Plume Off Namibia |
| Description |
Off the coast of Namibia in southwest Africa, a cold, deep current snakes northward past the Namib Desert carrying icy waters from deep in the Southern Ocean off Antarctica. Year-round southerly winds cause the warmer surface waters near the coast to be deflected westward away from shore, and the cold waters of the Benguela Current rise up from the depths to replace them. In the ocean, the welling up of cold water has a positive influence on living organisms. As ocean organisms grow and reproduce in the surface waters of the ocean, they use up the nutrients there. Cold waters welling up from deep in the ocean replenish those nutrients and often result in a rapid increase in marine plant life, called a bloom. The individual, microscopic plants, called phytoplankton, live just a few days, and when they die their remains sink to the bottom of the ocean, where they build up in the mud on the coastal floor. Bottom-dwelling bacteria chew through this rich belt of coastal mud, decomposing the phytoplankton remains. The result of this decomposition can be seen in this true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from the Terra satellite on January 9, 2003, in which the coastal waters appear milky-green. Some bacteria consume oxygen as they break down the plant remains, giving off carbon dioxide and water as by-products. But eventually, all the oxygen is used up. At that point, other bacteria take over the decomposition. These bacteria use a form of sulfur when they decompose the organic matter, and give off hydrogen sulfide gas as a by- product. The hydrogen sulfide gas periodically bubbles up from the ocean bottom, and when it encounters more oxygen-rich water near the surface, a chemical reaction occurs that transforms the sulfide gas into pure sulfur. In the first stages of the reaction, the sulfur appears white, and in this image creates a milky-green green tinge to the water. When the transformation is more complete, the plume will look very green?a mixture of the yellow sulfur and blue water. Ironically, the region?s high productivity is also one of its greatest threats, since the hydrogen sulfide gas resulting from such an explosion of life and its inevitable decay is highly toxic to the fish and other marine animals that feed off the phytoplankton. Periodic die-offs of whole populations of fish and other commercial seafood are ongoing concerns for the regional fishing industry. Image courtesy Jacques Descloitres, MODIS Rapid Response Team at NASA GSFC |
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Flooding In Namibia
| Title |
Flooding In Namibia |
| Description |
In early May 2003, heavy rains in south central Africa led to flooding along Namibia?s Caprivi Strip. High waters along the Zambezi River and its tributaries displaced 25,000 people. The floodwaters can be seen in this false-color image (right) acquired on May 14, 2003, by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA?s Terra spacecraft. The floodwaters resemble a lake in the center of the image. In March, the flooding was much less extensive (left, acquired on March 27, 2003). During the dry season, this lake would be completely absent and the Zambezi River would resemble a barely visible, thin line. In this false-color image, water is black. Clouds appear as pale blue and white, and vegetated land is green and yellow. Image by Jesse Allen, based on data from the MODIS Rapid Response Team at NASA-GSFC |
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Flooding In Namibia
| Title |
Flooding In Namibia |
| Description |
In early May 2003, heavy rains in south central Africa led to flooding along Namibia?s Caprivi Strip. High waters along the Zambezi River and its tributaries displaced 25,000 people. The floodwaters can be seen in this false-color image (right) acquired on May 14, 2003, by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA?s Terra spacecraft. The floodwaters resemble a lake in the center of the image. In March, the flooding was much less extensive (left, acquired on March 27, 2003). During the dry season, this lake would be completely absent and the Zambezi River would resemble a barely visible, thin line. In this false-color image, water is black. Clouds appear as pale blue and white, and vegetated land is green and yellow. Image by Jesse Allen, based on data from the MODIS Rapid Response Team at NASA-GSFC |
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Flooding in Namibia
| Title |
Flooding in Namibia |
| Description |
Several days of heavy rain triggered devastating floods in south-central Namibia at the end of February 2006. The rains filled the Hardap Dam, and on Saturday, February 25, the water flowed through the flood gates and flooded the city of Mariental. When the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image on February 27, the overflow of water had swollen the Fish River south of the city. The bright green agricultural region around the city was also still flooded when this image was taken. According to the United Nations Office for the Coordination of Humanitarian Affairs, 122 houses and 80 businesses were submerged at the time of this image. Two people drowned in the floods. These images are shown in false color. Plant-covered land is green, with agricultural land much brighter than natural vegetation. Bare earth is tan and pink, water is blue, and clouds are pale blue and white. The lower image shows the Hardap region on February 15 before the rains started. NASA images created by Jesse Allen, Earth Observatory, using data obtained from the Goddard Earth Sciences DAAC. |
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Flooding in Namibia
| Title |
Flooding in Namibia |
| Description |
Several days of heavy rain triggered devastating floods in south-central Namibia at the end of February 2006. The rains filled the Hardap Dam, and on Saturday, February 25, the water flowed through the flood gates and flooded the city of Mariental. When the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image on February 27, the overflow of water had swollen the Fish River south of the city. The bright green agricultural region around the city was also still flooded when this image was taken. According to the United Nations Office for the Coordination of Humanitarian Affairs, 122 houses and 80 businesses were submerged at the time of this image. Two people drowned in the floods. These images are shown in false color. Plant-covered land is green, with agricultural land much brighter than natural vegetation. Bare earth is tan and pink, water is blue, and clouds are pale blue and white. The lower image shows the Hardap region on February 15 before the rains started. NASA images created by Jesse Allen, Earth Observatory, using data obtained from the Goddard Earth Sciences DAAC. |
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Flooding In Namibia: Natural
…
nasa, nasanaturalhazards
In early May 2003, heavy rai
…
namibia_14may03_721_3
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2003-05-14 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
namibia_14may03_721_3 |
|
Flooding In Namibia: Natural
…
nasa, nasanaturalhazards
In early May 2003, heavy rai
…
namibia_14may03_721_3
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2003-05-14 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
namibia_14may03_721_3 |
|
Aircraft on SAFARI : Image o
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nasa, nasaimageofthedaygalle
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The South African Regional S
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safari_er2
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2000 |
| creator |
NASA -- Photograph by EOS Project Science Office |
| identifier |
safari_er2 |
|
Flooding on the Zambezi Rive
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nasa, nasanaturalhazards
* eoimages.gsfc.nasa.gov/ima
…
zambezi_amo_2006101
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-04-11 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
zambezi_amo_2006101 |
|
Floods in Namibia: Natural H
…
nasa, nasanaturalhazards
* eoimages.gsfc.nasa.gov/ima
…
Namibia_TMO_2008085
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008-03-25 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_TMO_2008085 |
|
Floods in Southern Africa: N
…
nasa, nasanaturalhazards
* eoimages.gsfc.nasa.gov/ima
…
Mozambique_TMO_2007041
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-01-10 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Mozambique_TMO_2007041 |
|
Floods in Namibia: Natural H
…
nasa, nasanaturalhazards
* eoimages.gsfc.nasa.gov/ima
…
Namibia_TMO_2008075
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008-03-15 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_TMO_2008075 |
|
Sulfur Plume Off Namibia: Im
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nasa, nasaimageofthedaygalle
…
Off the coast of Namibia in
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Namibia.TMOA2003009
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2003-01-09 |
| creator |
NASA -- Image courtesy Jacques Descloitres, rapidfire.sci.gsfc.nasa.gov MODIS Rapid Response Team at NASA GSFC |
| identifier |
Namibia.TMOA2003009 |
|
Flooding in Namibia: Natural
…
nasa, nasanaturalhazards
* eoimages.gsfc.nasa.gov/ima
…
namibia_TMO_2006058
| mediatype |
IMAGE |
| mediatype |
image |
| date |
February 27, 2006 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
namibia_TMO_2006058 |
|
Dust Plumes off Namibia: Nat
…
nasa, nasanaturalhazards
Many plumes of desert dust (
…
Namibia_TMO2004161
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-06-09 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_TMO2004161 |
|
Dust Plumes off Namibia: Nat
…
nasa, nasanaturalhazards
Whisps of white dust sweep o
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Namibia2_TMO_2004161
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-06-09 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia2_TMO_2004161 |
|
Dust Plumes off Namibia: Nat
…
nasa, nasanaturalhazards
Whisps of white dust sweep o
…
Namibia2_TMO_2004161
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-06-09 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia2_TMO_2004161 |
|
Fires in Central and Souther
…
nasa, nasanaturalhazards
The southern Africa burning
…
angola_12sep02
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2002-09-12 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
angola_12sep02 |
|
Hydrogen Sulfide Eruption Al
…
nasa, nasanaturalhazards
Bright colors in the ocean w
…
Namibia_TMO2004101
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-04-10 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_TMO2004101 |
|
Hydrogen Sulfide Eruption Al
…
nasa, nasanaturalhazards
Bright colors in the ocean w
…
Namibia_TMO2004101
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-04-10 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_TMO2004101 |
|
Seasonal floods along the Za
…
nasa, nasanaturalhazards
Officials in Namibia worked
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terra_zambezi_17apr04
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-04-17 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
terra_zambezi_17apr04 |
|
Hydrogen Sulfide Eruptions a
…
nasa, nasanaturalhazards
On April 18, 2004, the modis
…
Namibia_AMO2004109
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-04-18 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_AMO2004109 |
|
Hydrogen Sulfide Eruptions A
…
nasa, nasanaturalhazards
People living along Namibia'
…
ge_13155
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-05-12 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_13155 |
|
Hydrogen Sulfide Eruptions A
…
nasa, nasanaturalhazards
People living along Namibia'
…
ge_13155
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-05-12 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_13155 |
|
Hydrogen Sulfide Eruption Al
…
nasa, nasanaturalhazards
A milky green cloud of water
…
Namibia_TMO2004065
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-03-05 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_TMO2004065 |
|
Hydrogen Sulfide Eruption Al
…
nasa, nasanaturalhazards
A milky green cloud of water
…
Namibia_TMO2004065
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-03-05 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_TMO2004065 |
|
MISR Images Zambia and Botsw
…
PIA02621
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
MISR Images Zambia and Botswana |
| Original Caption Released with Image |
These MISR images of Zambia and Botswana, Africa were acquired on August 25, 2000 during Terra orbit 3655. The left image is a "true" color view from the vertical-viewing (nadir) camera. True color means that the images acquired through MISR's red, green, and blue filters, respectively, are displayed as red, green, and blue when creating the digital image. The middle image combines data from the green, red, and near-infrared bands. The right image contains red band data only, but is a composite of imagery from the nadir (An), 70.5-degrees forward (Df), and 70.5-degrees aftward (Da) cameras. The color variations in the multi-angle composite arise not from how the different parts of the scene reflect light at different wavelengths, but rather, at different angles. The distinctive fan-like feature on the left of each image is the highly vegetated Okavango Delta, a mosaiced network of grasslands and water channels, observed here during the dry season. The town of Maunis at its southeastern edge. Note how the plant life, which is highly reflective in the near-infrared, shows up as bright red in the middle image. Vegetation also preferentially reflects light back toward the source of illumination, so in the right image, the Df camera image, which is displayed in green, is brighter in this region. The body of water in the upper right is the Itezhi-Tezhi Dam, fed by the Kafue River in Zambia. At the lower left, south of the Okavango Delta, is Lake Ngami. A smoke plume is present at the southern edge of the lake. This plume and others show up in shades of blue and purple in the multi-angle composite as a result of the manner in which the smoke particles scatter sunlight. Other landmarks include the Ntwetwe Pan, whose western edge is visible as the bright area in the lower right. The Zambezi River enters from the upper left and wends its way southeast, passing the Caprivi Strip, a narrow panhandle in northeast Namibia. The greater abundance of vegetation here testifies to the high rainfall that occurs during the wet season. Near the right-hand edge of the images is the location where the Zambezi plunges into Victoria Falls, considered to be among the most spectacular waterfalls in the world. 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. |
|
Seasonal Surface Changes in
…
PIA04320
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Seasonal Surface Changes in Namibia and Central Angola |
| Original Caption Released with Image |
Brightness variations in the terrain along a portion of southwestern Africa are displayed in these views from the Multi-angle Imaging SpectroRadiometer (MISR). The panels portray an area that includes Namibia's Skeleton Coast and Etosha National Park as well as Angola's Cuando Cubango. The top panels were acquired on March 6, 2001, during the region's wet season, and the bottom panels were acquired on September 1, 2002, during the dry season. Corresponding changes in the abundance of vegetation are apparent. The images on the left are natural color (red, green, blue) images from MISR's vertical-viewing (nadir) camera. The images on the right represent one of MISR's derived surface products. The radiance (light intensity) in each pixel of the so-called "top-of-atmosphere" images on the left includes light that is reflected by the Earth's surface in addition to light that is transmitted and reflected by the atmosphere. The amount of radiation reflected by the surface into all upward directions, as opposed to any single direction, is important when studying Earth's energy budget. A quantity called the surface "directional hemispherical reflectance" (DHR), sometimes called the "black-sky albedo", captures this information, and is depicted in the images on the right. MISR's multi-angle views lead to more accurate estimates of the amount of radiation reflected into all directions than can be obtained as a result of looking at a single (e.g., vertically downward) view angle. Furthermore, to generate this surface product accurately, it is necessary to compensate for the effects of the intervening atmosphere, and MISR provides the ability to characterize and account for scattering of light by airborne particulates (aerosols). The DHR is called a hemispherical reflectance because it measures the amount of radiation reflected into all upward directions, and which therefore traverses an imaginary hemisphere situated above each surface point. The "directional" part of the name describes the illumination geometry, and indicates that in the absence of an intervening atmosphere, light from the Sun illuminates the surface from a single direction (that is, there is no diffuse skylight, hence the "black-sky" terminology). The DHR is retrieved over land surfaces in each of MISR's four wavelength bands, and the images on the right are red, green, blue spectral composites. Regions where DHR could not be derived, either due to an inability to retrieve the necessary atmospheric characteristics or due to the presence of clouds, are shown in dark gray. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbits 6466 and 14388. The panels cover an area of about 380 kilometers x 760 kilometers, and utilize data from blocks 102 to 107 within World Reference, System-2 path 181. 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. |
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