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Fires on Borneo and Sumatra
| Title |
Fires on Borneo and Sumatra |
| Description |
In Sumatra and Indonesia, seasonal fires and the thick smoke they produce plagued the islands for nearly two months in late 2006. Beginning in mid-September 2006, the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] and Aqua [ http://aqua.nasa.gov ] satellites detected numerous fires in daily images of the area. This image was captured by Aqua MODIS on November 5, 2006. Active fire locations are marked with red dots. Thick smoke spreads between the two islands, the grayish haze mingling with brighter clouds. Many factors contribute to the fires, which usually start from agricultural burning, but often spread into adjacent tropical forest. When the forests have been degraded by logging, they become much more prone to fire. In addition, climate fluctuations, such as droughts that occur in concert with El Niño events, can make the fires worse. During droughts, the typically soggy forest floor of these lowland forests dries out. The thick layer of dead vegetation on the forest floor, peat, becomes flammable and produces enormous quantities of smoke when it burns. You can download a 250-meter-resolution KMZ file [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Nov2006/indonesia_amo_2006309.kmz ] of Borneo and Sumatra for use with Google Earth. [ http://earth.google.com/download-earth.html ] NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of the MODIS Rapid Response [ http://rapidfire.sci.gsfc.nasa.gov/ ] team. |
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Floods in East Africa
| Title |
Floods in East Africa |
| Description |
Kenya gets most of its rainfall in two doses: a long rainy season that runs from March or April through July or August, and a short rainy season that starts in September or October and usually tapers off in December. As if trying to make up for lack of rain during the 2005 short rainy season, [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17250 ]which failed entirely, the rainy season that started in October 2006 proved to be unusually heavy. Some locations in Kenya received as much as 200 millimeters more rain than average in October. The heavy rain fell on drought-baked ground, triggering extensive flooding in northern Kenya. The East Africa Standard, [ http://allafrica.com/stories/200610280016.html ] a Nairobi newspaper, reported on October 28 that 10 people had died in the flooding and more than 75,000 were made homeless. The Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured the top image of flooding in northern Kenya on October 30, 2006. Aquamarine, sediment-laden flood water runs through the Laga Bogal and Laga Bor river channels and spreads across the surrounding landscape in places. The Lorian Swamp, in the lower-right corner of the image, appeared dry on October 14, when the lower image was captured. By October 30, water flowed through the swamp. The rain has also spurred plant growth. The arid landscape assumed a green tint in the two weeks that passed between October 14 and October 30. In these false-color images, made with both infrared and visible light, vegetation is bright green, bare or sparsely vegetated ground is tan-pink, and clouds are pale blue and white. In this type of image, water is typically black or dark blue, but sediment has given the water a blue-green color in the top image. Eastern Africa regularly goes through cycles of drought and floods, possibly driven by El Niño. El Niño is a cyclical warming of ocean waters in the central and eastern Pacific that can alter weather patterns around the world. In general, El Niño causes drought in some regions like Indonesia, Australia, and the Philippines, while bringing excess rain to others, including East Africa and the southwestern United States. In September 2006, NASA's JASON satellite recorded a mild El Niño [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17419 ] in the tropical Pacific Ocean. At the same time, drought [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13943 ] was settling in over Australia and heavy rain pounded East Africa.Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NAfrica_3_07 ] of East Africa are provided by the MODIS Rapid Response Team at NASA Goddard Space Flight Center. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Floods in East Africa
| Title |
Floods in East Africa |
| Description |
Kenya gets most of its rainfall in two doses: a long rainy season that runs from March or April through July or August, and a short rainy season that starts in September or October and usually tapers off in December. As if trying to make up for lack of rain during the 2005 short rainy season, [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17250 ]which failed entirely, the rainy season that started in October 2006 proved to be unusually heavy. Some locations in Kenya received as much as 200 millimeters more rain than average in October. The heavy rain fell on drought-baked ground, triggering extensive flooding in northern Kenya. The East Africa Standard, [ http://allafrica.com/stories/200610280016.html ] a Nairobi newspaper, reported on October 28 that 10 people had died in the flooding and more than 75,000 were made homeless. The Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured the top image of flooding in northern Kenya on October 30, 2006. Aquamarine, sediment-laden flood water runs through the Laga Bogal and Laga Bor river channels and spreads across the surrounding landscape in places. The Lorian Swamp, in the lower-right corner of the image, appeared dry on October 14, when the lower image was captured. By October 30, water flowed through the swamp. The rain has also spurred plant growth. The arid landscape assumed a green tint in the two weeks that passed between October 14 and October 30. In these false-color images, made with both infrared and visible light, vegetation is bright green, bare or sparsely vegetated ground is tan-pink, and clouds are pale blue and white. In this type of image, water is typically black or dark blue, but sediment has given the water a blue-green color in the top image. Eastern Africa regularly goes through cycles of drought and floods, possibly driven by El Niño. El Niño is a cyclical warming of ocean waters in the central and eastern Pacific that can alter weather patterns around the world. In general, El Niño causes drought in some regions like Indonesia, Australia, and the Philippines, while bringing excess rain to others, including East Africa and the southwestern United States. In September 2006, NASA's JASON satellite recorded a mild El Niño [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17419 ] in the tropical Pacific Ocean. At the same time, drought [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13943 ] was settling in over Australia and heavy rain pounded East Africa.Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NAfrica_3_07 ] of East Africa are provided by the MODIS Rapid Response Team at NASA Goddard Space Flight Center. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Floods in East Africa
| Title |
Floods in East Africa |
| Description |
Severe drought early in 2006 followed by widespread flooding [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13795 ] during August crippled Ethiopia. In late October and early November, the disaster continued to develop as heavy rain once again sent the Wabe Shebele River over its banks. The swollen river grew to twice its normal size, inundating towns that line its fertile banks, reported the World Food Program [ http://www.alertnet.org/thenews/newsdesk/WFP/4d4580f3cc2d9d49654e66a8daf84c16.htm ]. More than 60 people died in the floods, and many more were impacted. On November 1, 2006, skies cleared, providing the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite a clear view of the floods in southeastern Ethiopia. The Wabe Shabele spreads several kilometers across its flood plain, its water ranging from inky black to light blue. The scene is shown in infrared-enhanced false color to highlight the presence of water on the ground. In this color combination, made with both visible and infrared light, water is typically black, as it is in the lower reaches of the river in this image. Elsewhere in the scene, however, water is light blue because sediment in the water scatters light. The pale blue color blends with the light green of newly growing plants, making it difficult to tell just how extensive the floods are on the west bank of the river. Other waterways on either side of the Wabe Shabele are also filled with mud-laden, light blue water. The lower image, taken on October 7, shows the Wabe Shabele under normal conditions. Though the river is prone to flooding, the attractiveness of living along its banks is clear from this image. Little vegetation is growing in the arid region except along the river's banks, which are lined in green. Conditions changed by November 1. The same rainfall that caused the floods also spurred plant growth, and the landscape went from a barren tan-pink to verdant green. Lines of high clouds, pale blue and white in this false-color image, are scattered across both images. Like much of East Africa, southeastern Ethiopia goes through a regular cycle of floods and droughts. The cycle is in part driven by El Niño, a cyclical warming of ocean waters in the central and eastern Pacific that can alter weather patterns around the world. In general, El Niño causes drought in some regions, such as Indonesia, Australia, and the Philippines, while bringing excess rain to others, including East Africa and the southwestern United States. In September 2006, NASA's JASON satellite recorded a weak El Niño [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17419 ] in the tropical Pacific Ocean. At the same time, drought [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13943 ], was settling in over Australia, and heavy rain pounded East Africa. NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the MODIS Rapid Response [ http://rapidfire.sci.gsfc.nasa.gov/ ] team. |
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Floods in East Africa
| Title |
Floods in East Africa |
| Description |
Severe drought early in 2006 followed by widespread flooding [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13795 ] during August crippled Ethiopia. In late October and early November, the disaster continued to develop as heavy rain once again sent the Wabe Shebele River over its banks. The swollen river grew to twice its normal size, inundating towns that line its fertile banks, reported the World Food Program [ http://www.alertnet.org/thenews/newsdesk/WFP/4d4580f3cc2d9d49654e66a8daf84c16.htm ]. More than 60 people died in the floods, and many more were impacted. On November 1, 2006, skies cleared, providing the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite a clear view of the floods in southeastern Ethiopia. The Wabe Shabele spreads several kilometers across its flood plain, its water ranging from inky black to light blue. The scene is shown in infrared-enhanced false color to highlight the presence of water on the ground. In this color combination, made with both visible and infrared light, water is typically black, as it is in the lower reaches of the river in this image. Elsewhere in the scene, however, water is light blue because sediment in the water scatters light. The pale blue color blends with the light green of newly growing plants, making it difficult to tell just how extensive the floods are on the west bank of the river. Other waterways on either side of the Wabe Shabele are also filled with mud-laden, light blue water. The lower image, taken on October 7, shows the Wabe Shabele under normal conditions. Though the river is prone to flooding, the attractiveness of living along its banks is clear from this image. Little vegetation is growing in the arid region except along the river's banks, which are lined in green. Conditions changed by November 1. The same rainfall that caused the floods also spurred plant growth, and the landscape went from a barren tan-pink to verdant green. Lines of high clouds, pale blue and white in this false-color image, are scattered across both images. Like much of East Africa, southeastern Ethiopia goes through a regular cycle of floods and droughts. The cycle is in part driven by El Niño, a cyclical warming of ocean waters in the central and eastern Pacific that can alter weather patterns around the world. In general, El Niño causes drought in some regions, such as Indonesia, Australia, and the Philippines, while bringing excess rain to others, including East Africa and the southwestern United States. In September 2006, NASA's JASON satellite recorded a weak El Niño [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17419 ] in the tropical Pacific Ocean. At the same time, drought [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13943 ], was settling in over Australia, and heavy rain pounded East Africa. NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the MODIS Rapid Response [ http://rapidfire.sci.gsfc.nasa.gov/ ] team. |
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Jason Satellite Observes Mil
…
PIA01939
Sol (our sun)
Altimeter
| Title |
Jason Satellite Observes Mild El Nino in 2006 |
| Original Caption Released with Image |
In September 2006, NASA satellite data indicated that El Niño had returned to the tropical Pacific Ocean, although it was relatively weak. As of early October, scientists were not sure if the event would persist, and it was much less intense than the last major El Niño episode, which happened in 1997-1998. That event brought devastating floods to California that cost millions of dollars in damage while severe drought struck Indonesia, Australia, and the Philippines. Among the ocean characteristics that signal developing El Niño events is a change in average sea surface height compared to normal sea level. When water warms, it expands a little, which changes its volume slightly. When heat begins to build up in the Pacific during an El Niño event, the sea surface height begins to creep up. NASA observes changes in average sea surface height using its Jason satellite. The image is based on the average of 10 days of data centered on September 15, 2006, compared to the long-term average of observations from 1993-2005. In this image, places where the Pacific sea surface height is higher (warmer) than normal are yellow, orange, and red, and places where the sea surface is lower (cooler) than normal are blue and purple. Green shows where conditions are near normal. The swath of red in the center of the scene reveals that an El Niño was in progress when Jason observed the Pacific. El Niño is a cyclical warming of the ocean waters in the central and eastern tropical Pacific that generally occurs every 3 to 7 years. It is linked with changes in air pressure and high-level winds that can affect weather worldwide. Typically peaking during the Northern Hemisphere winter months, El Niño is the warm phase of the El Niño/Southern Oscillation. It alternates with La Niña, the cooling of ocean waters in the same region of the Pacific. According to Bill Patzert, oceanographer and climatologist at NASA's Jet Propulsion Laboratory, "The present conditions indicate that the intensity of this El Niño is too weak to have a major influence on current weather patterns. But, if the ocean waters continue to warm and spread eastward, this event would likely strengthen, perhaps bringing much-needed rainfall to the southwestern and southeastern United States this winter." The Jason satellite carries a dual-frequency radar altimeter. This instrument beams microwave pulses-at 13.6 and 5.3 Gigahertz, respectively-downward toward the Earth. To determine the ocean's height, the instrument precisely measures the time it takes for the microwave pulses to bounce off the surface and return to the spacecraft. This measure, multiplied by the speed of light, gives the range from the satellite to the ocean surface. The joint U.S.-French Topex/Poseidon mission is managed by the JPL for NASA's Science Mission Directorate, NASA Headquarters, Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena. Research on Earth's oceans using Jason and other, space-based capabilities is conducted by NASA's Science Mission Directorate to better understand and protect our home planet. For more information on NASA's ocean surface topography missions, see http://sealevel.jpl.nasa.gov/ [ http://sealevel.jpl.nasa.gov/ ] or to view the latest Jason data see http://sealevel.jpl.nasa.gov/science/jason1-quick-look/ [ http://sealevel.jpl.nasa.gov/science/jason1-quick-look/ ]. |
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