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Central Africa Dust Storm
| Title |
Central Africa Dust Storm |
| Description |
An intense dust storm across Central Africa nearly hides the land from the view of the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite on March 8, 2004. In the heart of Africa, the dust is hanging over the countries of (clockwise from top left) Nigeria, Cameroon, Chad, and the Central African Republic. A few fires (marked in red) were still able to be detected through the thick air, and their smoke may be contributing to the haze. The high-resolution image provided above is 500 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions. Image courtesy Jeff Schmaltz, MODIS Rapid Response Team, NASA-GSFC |
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Dust Storm in Chad
| Title |
Dust Storm in Chad |
| Description |
A dust storm blew through part of eastern Chad on June 11, 2006. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] flying onboard NASA's Terra [ http://terra.nasa.gov/ ] satellite captured this image of the storm as it blew toward Lake Chad. In this image, the dust appears as a wisp of pale beige set against a darker tan background. Lake Chad, near the border with Nigeria and Cameroon, is barely visible in this image, although it has been easily discernible in other [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=11952 ] satellite images. Although large, Lake Chad is shallow, and it is not the lowest point in Chad. Sitting at an even lower elevation is the Bodele Depression in eastern central Chad. The Bodele Depression, [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=12581 ] part of a former lake bed or inland sea, is one of the world's most active sources of windblown dust, and it was likely the source of this storm. A study published in 2004 demonstrated that dust storms move more rapidly [ http://eobglossary.gsfc.nasa.gov/Newsroom/NewImages/images.php3?img_id=16534 ] across the depression than previously assumed. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. The MODIS Rapid Response Team provides daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NAfrica_2_05/ ] of this region. |
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Dust Storm in the Bodele Dep
…
| Title |
Dust Storm in the Bodele Depression |
| Description |
The air over central Africa was bright with blowing dust (top) and what is probably a mixture of dust and smoke (left center) when this image of the area around Lake Chad (large green area above image center) was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite was captured on November 28, 2004. In addition to the dust storm in the Bodele Depression north of Lake Chad, numerous fires (locations marked in red) burning in the Sahel and savannas of Nigeria, Cameroon, Chad, and the Central Africa Republic were contributing to the atmospheric haze. NASA image created by Jesse Allen, Earth Observatory, using data obtained from the Goddard Land Processes DAAC. |
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Dust Storm in the Bodele Dep
…
| Title |
Dust Storm in the Bodele Depression |
| Description |
A dust storm in Central Africa that began in late December 2004 intensified in the first week of January 2005. In the southern Sahara Desert, a large low-lying area known as the Bodele Depression is one of the largest sources of wind-blown dust on Earth. In this image from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite, captured on January 6, the thick cloud of dust begins in Chad (upper right) and spreads outward over neighboring countries. Along the southern edges of the cloud, smaller rivers of dust weave over the green landscapes of the Sahel and savannas in Nigeria, Cameroon, and the Central African Republic. In the bottom of the scene, an arc of fires spreads across those countries as well. The red dots show the locations where MODIS detected active fires. The widespread nature of the fires and the time of year suggest that these fires are being set intentionally for agricultural purposes. Though not necessarily immediately hazardous, such large-scale burning can have a strong impact on weather, climate, human health, and natural resources. The high-resolution image provided above is 500 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions. Image courtesy Jacques Descloitres, MODIS Rapid Response Team, NASA-Goddard Space Flight Center |
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Dust Storm off Western Sahar
…
| Title |
Dust Storm off Western Sahara Coast |
| Description |
In central and western Africa on February 14, 2005, waves of dust billowed outward from interior deserts, blanketing more than a dozen countries with a tan-colored haze that ultimately stretched out over the Atlantic Ocean. Dust is particularly thick in the countries to the south of Lake Chad, including Cameroon and Nigeria. The thickness of the dust in those areas almost completely hides the underlying savanna, giving the image the appearance of a watercolor painting. This image was made by combining observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA?s Terra [ http://terra.nasa.gov ] satellite during two consecutive overpasses of the satellite. Image courtesy the MODIS Rapid Response Team [ http://rapidfire.s,ci.gfc.nasa.gov ], NASA-GSFC |
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Dust Storms from Africa's Bo
…
| Title |
Dust Storms from Africa's Bodele Depression |
| Description |
Once serving as part of the floor for a much larger Lake Chad, the area now known as the Bodele Depression, located at the southern edge of the Sahara Desert in north central Africa, is slowly being transformed into a desert landscape. In the mid-1960s, Lake Chad was about the size of Lake Erie. But persistent drought conditions coupled with increased demand for freshwater for irrigation have reduced Lake Chad to about 5 percent of its former size. As the waters receded, the silts and sediments resting on the lakebed were left to dry in the scorching African sun. The small grains of the silty sand are easily swept up by the strong wind gusts that occasionally blow over the region. Once heaved aloft, the Bodele dust can be carried for hundreds or even thousands of kilometers. The remnants of Lake Chad appear as the olive-green feature set amid the tan and light brown hues of the surrounding landscape where the countries of Chad, Niger, Nigeria, and Cameroon all share borders. The Bodele Depression was the source of some very impressive dust storms that have swept over West Africa [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=11939 ] and the Cape Verde Islands [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=11935 ] in recent days. This true-color image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS), flying aboard NASA?s Terra satellite, on February 7, 2004. A similar image was acquired later that same day by the MODIS instrument aboard NASA?s Aqua satellite. The high-resolution image available here is 500 meters per pixel, but both scenes are available at up to 250 meters per pixel?the sensor?s maximum resolution. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov/ ] at NASA GSFC |
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Dust Storms from Africa's Bo
…
| Title |
Dust Storms from Africa's Bodele Depression |
| Description |
Once serving as part of the floor for a much larger Lake Chad, the area now known as the Bodele Depression, located at the southern edge of the Sahara Desert in north central Africa, is slowly being transformed into a desert landscape. In the mid-1960s, Lake Chad was about the size of Lake Erie. But persistent drought conditions coupled with increased demand for freshwater for irrigation have reduced Lake Chad to about 5 percent of its former size. As the waters receded, the silts and sediments resting on the lakebed were left to dry in the scorching African sun. The small grains of the silty sand are easily swept up by the strong wind gusts that occasionally blow over the region. Once heaved aloft, the Bodele dust can be carried for hundreds or even thousands of kilometers. The remnants of Lake Chad appear as the olive-green feature set amid the tan and light brown hues of the surrounding landscape where the countries of Chad, Niger, Nigeria, and Cameroon all share borders. The Bodele Depression was the source of some very impressive dust storms that have swept over West Africa [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=11939 ] and the Cape Verde Islands [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=11935 ] in recent days. This true-color image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS), flying aboard NASA?s Terra satellite, on February 7, 2004. A similar image was acquired later that same day by the MODIS instrument aboard NASA?s Aqua satellite. The high-resolution image available here is 500 meters per pixel, but both scenes are available at up to 250 meters per pixel?the sensor?s maximum resolution. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov/ ] at NASA GSFC |
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Saharan Dust Storm
| Title |
Saharan Dust Storm |
| Description |
A dust storm swept across the Sahara Desert on May 10, 2006, moving dust across Niger, Nigeria, Cameroon, and Chad. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] flying onboard the Terra [ http://terra.nasa.gov/ ] satellite took this picture the same day. In this image, the dust appears as a pale beige plume that sweeps westward over the desert. White clouds dot the skies around the fringes of the storm. NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC |
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Floods Across Africa's Sahel
| Title |
Floods Across Africa's Sahel |
| Description |
A tangle of rivers weaves across the uneven landscape of southwestern Chad, creating the wetlands that surround the Logone River. The backbone of the intersecting rivers in these images, the Logone flows northeast through Chad, forming part of the border with Cameroon, before joining the Chari River and emptying into Lake Chad. On September 26, 2006, 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, the wetlands around the Logone were dark with water. Western Chad, like many other countries in Africa's Sahel region, experienced widespread flooding because of unusually heavy rains in August and September. According to the Dartmouth Flood Observatory, [ http://www.dartmouth.edu/%7efloods/Archives/2006sum.htm ] floods in Chad and Nigeria displaced tens of thousands of people and caused extensive agricultural and infrastructure losses. In the top image, floods, not evident two weeks earlier, form dark pools along the Logone River. These images are displayed in false color to highlight the presence of water. Here, water is black or dark blue, clouds are pale blue and white, plant-covered land is green, and lightly vegetated land is tan. Natural-color and false-color [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NAfrica_3_05/2006269 ] images of Chad are available from the MODIS Rapid Response Team twice daily. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Floods Across Africa's Sahel
| Title |
Floods Across Africa's Sahel |
| Description |
A tangle of rivers weaves across the uneven landscape of southwestern Chad, creating the wetlands that surround the Logone River. The backbone of the intersecting rivers in these images, the Logone flows northeast through Chad, forming part of the border with Cameroon, before joining the Chari River and emptying into Lake Chad. On September 26, 2006, 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, the wetlands around the Logone were dark with water. Western Chad, like many other countries in Africa's Sahel region, experienced widespread flooding because of unusually heavy rains in August and September. According to the Dartmouth Flood Observatory, [ http://www.dartmouth.edu/%7efloods/Archives/2006sum.htm ] floods in Chad and Nigeria displaced tens of thousands of people and caused extensive agricultural and infrastructure losses. In the top image, floods, not evident two weeks earlier, form dark pools along the Logone River. These images are displayed in false color to highlight the presence of water. Here, water is black or dark blue, clouds are pale blue and white, plant-covered land is green, and lightly vegetated land is tan. Natural-color and false-color [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NAfrica_3_05/2006269 ] images of Chad are available from the MODIS Rapid Response Team twice daily. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Widely Scattered Fires acros
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| Title |
Widely Scattered Fires across Central Africa |
| Description |
This pair of images from December 11, 2002, shows the diurnal (daily cycle) fire patterns in central Africa. The top image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite in the morning, while the bottom image was captured by the MODIS on the Aqua satellite in the afternoon. From left to right, this image spans the countries of Nigeria, Cameroon, Chad, and the Central African Republic. At bottom right, a portion of Democratic Republic of Congo is visible. As the day progressed, fire activity (indicated by red dots) increased markedly. The increase is due to both human and environmental factors. Many, if not most, of these fires are set by humans for agricultural purposes: clearing farmland, returning nutrients to the soil, regenerating pasture. People become more active over the course of the day, and fire occurrence increases. Fire activity is also influenced by increasing temperatures and decreasing humidity as the morning progresses to afternoon. This increases the potential for planned fires to get out of control or to burn larger areas than intended. Another interesting difference between the morning and afternoon overpasses is how the relative position of the sun and the satellite during each overpass changes the appearance of the vegetation. Notice that in the Terra overpass, when the light from the sun would have been coming from the southeast, the vegetation at the right of the image appears dark, and the vegetation in the left half of the image appears bright. During the Aqua overpass, the reverse is true: the sun is coming from the southwest, and the vegetation appears bright in the east and dark in the west. This apparent change in surface observations due to change in the relative positions of the sun and the spacecraft is referred to as the bidirectional effect, and scientists must take the effect into consideration when using satellite data to study surface features on Earth. Image courtesy Jacques Descloitres, MODIS Rapid Response Team at NASA GSFC |
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Widely Scattered Fires acros
…
| Title |
Widely Scattered Fires across Central Africa |
| Description |
This pair of images from December 11, 2002, shows the diurnal (daily cycle) fire patterns in central Africa. The top image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite in the morning, while the bottom image was captured by the MODIS on the Aqua satellite in the afternoon. From left to right, this image spans the countries of Nigeria, Cameroon, Chad, and the Central African Republic. At bottom right, a portion of Democratic Republic of Congo is visible. As the day progressed, fire activity (indicated by red dots) increased markedly. The increase is due to both human and environmental factors. Many, if not most, of these fires are set by humans for agricultural purposes: clearing farmland, returning nutrients to the soil, regenerating pasture. People become more active over the course of the day, and fire occurrence increases. Fire activity is also influenced by increasing temperatures and decreasing humidity as the morning progresses to afternoon. This increases the potential for planned fires to get out of control or to burn larger areas than intended. Another interesting difference between the morning and afternoon overpasses is how the relative position of the sun and the satellite during each overpass changes the appearance of the vegetation. Notice that in the Terra overpass, when the light from the sun would have been coming from the southeast, the vegetation at the right of the image appears dark, and the vegetation in the left half of the image appears bright. During the Aqua overpass, the reverse is true: the sun is coming from the southwest, and the vegetation appears bright in the east and dark in the west. This apparent change in surface observations due to change in the relative positions of the sun and the spacecraft is referred to as the bidirectional effect, and scientists must take the effect into consideration when using satellite data to study surface features on Earth. Image courtesy Jacques Descloitres, MODIS Rapid Response Team at NASA GSFC |
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Dust Storms from Africa's Bo
…
nasa, nasanaturalhazards
Once serving as part of the
…
Bodele_TMO2004042
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-02-11 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Bodele_TMO2004042 |
|
Fires across the Sahel : Ima
…
nasa, nasaimageofthedaygalle
…
Each year in March and April
…
modis_sahel_2001061
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2001-03-02 |
| creator |
NASA -- Image courtesy Jacques Descloitres, modland.nascom.nasa.gov/ MODIS Land Rapid Response Team. |
| identifier |
modis_sahel_2001061 |
|
Saharan Dust Storm: Natural
…
nasa, nasanaturalhazards
A dust storm swept across th
…
sahara_tmo_2006130
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-05-10 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
sahara_tmo_2006130 |
|
Dust Storms from Africa's Bo
…
nasa, nasanaturalhazards
Once serving as part of the
…
Bodele_TMO2004038
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-02-07 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Bodele_TMO2004038 |
|
Floods Across Africa's Sahel
…
nasa, nasanaturalhazards
* eoimages.gsfc.nasa.gov/ima
…
Chad_TMO_2006269
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-09-26 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Chad_TMO_2006269 |
|
Central Africa Dust Storm: N
…
nasa, nasanaturalhazards
An intense dust storm across
…
WestAfrica.A2004068
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-03-08 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
WestAfrica.A2004068 |
|
Dust Storm off Western Sahar
…
nasa, nasanaturalhazards
In central and western Afric
…
NAfrica_dust.TMOA2005045
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-02-14 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
NAfrica_dust.TMOA2005045 |
|
Dust Storm in the Bodele Dep
…
nasa, nasanaturalhazards
The air over central Africa
…
terra_bodele_28nov04
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-11-28 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
terra_bodele_28nov04 |
|
Landslides in Cameroon: Imag
…
nasa, nasaimageofthedaygalle
…
The steep forested slopes of
…
aster_cameroon_08mar04
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-03-08 |
| creator |
NASA -- Image courtesy MITI, ERSDAC, JAROS, and the U.S./Japan asterweb.jpl.nasa.gov/ ASTER Science Team , caption information courtesy www.treemail.nl/privateers/cameroun/index.htm ParBleu technologies. |
| identifier |
aster_cameroon_08mar04 |
|
Dust Storm in the Bodele Dep
…
nasa, nasanaturalhazards
A dust storm in Central Afri
…
CAfrica.TMOA2005006
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-01-06 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
CAfrica.TMOA2005006 |
|
Dust Storm in Chad: Natural
…
nasa, nasanaturalhazards
A dust storm blew through pa
…
chad_tmo_2006162
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-06-11 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
chad_tmo_2006162 |
|
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