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More Los Angeles Fire Images
Triple-digit temperatures, e
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9/1/09
| Description |
Triple-digit temperatures, extremely low relative humidities, dense vegetation that has not burned in decades, and years of extended drought are all contributing to the explosive growth of wildfires throughout Southern California. The Station fire, which began Aug. 26, 2009, in La Canada/Flintridge, not far from NASA's Jet Propulsion Laboratory, had reportedly burned 105,000 acres (164 square miles) of the Angeles National Forest by mid-day Aug. 31, destroying at least 21 homes and threatening more than 12,000 others. It is one of four major fires burning in Southern California at the present time. This image was acquired mid-morning on Aug. 30 by the backward (northward)-viewing camera of the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite. The image is shown in an approximate perspective view at an angle of 46 degrees off of vertical. The area covered by the image is 245 kilometers (152 miles) wide. Several pyrocumulus clouds, created by the Station Fire, are visible above the smoke plumes rising from the San Gabriel Mountains north of Los Angeles in the left-center of the image. Smoke from the Station fire is seen covering the interior valleys along the south side of the San Gabriel Mountains, along with parts of the City of Los Angeles and Orange County, and can be seen drifting for hundreds of kilometers to the east over the Mojave Desert. The accompanying plots are histograms that display the heights of the smoke plumes and wind speeds. In this data set, the plume is injecting smoke more than 7 kilometers (4.3 miles) above sea level. MISR observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. This image was generated from a portion of the imagery acquired during Terra orbit 51601. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. The MISR data were obtained from the NASA Langley Research Center Atmospheric Science Data Center. JPL is a division of the California Institute of Technology. Image Credit: NASA/GSFC/LaRC/JPL, MISR Team |
| Date |
9/1/09 |
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LOS ALAMOS FIRE IMAGED BY NA
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The fire that has raged out
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5/19/00
| Date |
5/19/00 |
| Description |
The fire that has raged out of control this month near Los Alamos, New Mexico, was captured in a series of images by the Multi-angle Imaging Spectro-Radiometer (MISR) on NASA's Terra satellite. The picture is available at http://www.jpl.nasa.gov/pictures/misr These true-color images covering north-central New Mexico capture the bluish-white smoke plume of the Los Alamos fire, just west of the Rio Grande river. The middle image is a downward-looking or "nadir" view taken by MISR. As the satellite flew from north to south, the instrument viewed the scene from nine different angles. The top image was taken by the MISR camera looking 60 degrees forward along its orbit, whereas the bottom image looks 60 degrees aft. The fire plume stands out more dramatically in the steep-angle views. Its color and brightness also change with angle. By comparison, a thin, white water cloud appears in the upper right portion of the scene, and is most easily detected in the top image. MISR scientists use these angle-to-angle differences to monitor particulate pollution and to identify different types of haze. Such observations allow scientists to study how airborne particles interact with sunlight, a measure of their impact on Earth's climate system. The images are about 400 km (250 miles) wide. The spatial resolution of the nadir image is 275 meters (300 yards), resolution is 1.1 kilometers (1,200 yards) for the off-nadir images. North is toward the top. MISR is managed by the Jet Propulsion Laboratory, a division of the California Institute of Technology, for NASA' s Office of Earth Science, Washington, D.C. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. ##### Photo credit: NASA/GSFC/JPL, MISR Science Team. |
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Nicaraguan Volcanoes The tru
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| Description |
Nicaraguan Volcanoes The true-color image at left is a downward-looking (nadir) view of the area around the San Cristobal volcano, which erupted the previous day. This image is oriented with east at the top and north at the left. The right image is a stereo anaglyph of the same area, created from red band multi-angle data taken by the 45.6-degree aftward and 70.5-degree aftward cameras on the Multi- angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite. View this image through red/blue 3D glasses, with the red filter over the left eye. A plume from San Cristobal (approximately at image center) is much easier to see in the anaglyph, due to 3 effects: the long viewing path through the atmosphere at the oblique angles, the reduced reflection from the underlying water, and the 3D stereoscopic height separation. In this image, the plume floats between the surface and the overlying cumulus clouds. A second plume is also visible in the upper right (southeast of San Cristobal). This very thin plume may originate from the Masaya volcano, which is continually degassing at a slow rate. The spatial resolution is 275 meters (300 yards). 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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Multi-Angle Views of the App
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| Description |
Multi-Angle Views of the Appalachian Mountains The true-color image at left is a downward-looking (nadir) view of the eastern United States, stretching from Lake Ontario to northern Georgia, and spanning the Appalachian Mountains. The three images to the right are also in true-color, taken by the forward 45.6-degree, 60.0-degree, and 70.5-degree cameras, respectively, of the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite. As the slant angle increases, the line- of-sight through the atmosphere grows longer, and a pall of haze over the Appalachians becomes progressively more apparent. You can see a similar effect by scanning from near-nadir to the horizon when standing on a mountain top or looking out an airplane window. MISR uses this multi-angle technique to monitor particulate pollution and to distinguish different types of haze. These observations reveal how airborne particles are interacting with sunlight, a measure of their impact on Earth's climate system. The images are about 400 km (250 miles) wide, and the spatial resolution is 1.1 kilometers (1,200 yards). North is toward the top. 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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Multi-Angle View of the Cana
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A multi-angle view of the Ca
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| Description |
A multi-angle view of the Canary Islands in a dust storm, 29 February 2000. At left is a true-color image taken by the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite. This image was captured by the MISR camera looking at a 70.5-degree angle to the surface, ahead of the spacecraft. The middle image was taken by the MISR downward- looking (nadir) camera, and the right image is from the aftward 70.5-degree camera. The images are reproduced using the same radiometric scale, so variations in brightness, color, and contrast represent true variations in surface and atmospheric reflectance with angle. Windblown dust from the Sahara Desert is apparent in all three images, and is much brighter in the oblique views. This illustrates how MISR's oblique imaging capability makes the instrument a sensitive detector of dust and other particles in the atmosphere. Data for all channels are presented in a Space Oblique Mercator map projection to facilitate their co-registration. The images are about 400 km (250 miles) wide, with a spatial resolution of about 1.1 kilometers (1,200 yards). North is toward the top. 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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Multi-angle Images of Hudson
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At left is a true-color imag
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| Description |
At left is a true-color image from the downward-looking (nadir) camera on the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite. The false-color image at right is a composite of red band data taken by the MISR forward 45.6-degree, nadir, and aftward 45.6-degree cameras, displayed in blue, green, and red colors, respectively. Color variations in the left image highlight spectral (true-color) differences, whereas those in the right image highlight differences in angular reflectance properties. The purple areas in the right image are low cloud, and light blue at the edge of the bay is due to increased forward scattering by the fast (smooth) ice. The orange areas are rougher ice, which scatters more light in the backward direction. This example illustrates how multi-angle viewing can distinguish physical structures and textures. Data for all channels are presented in a Space Oblique Mercator map projection to facilitate their co- registration. The images are about 400 km (250 miles) wide with a spatial resolution of about 275 meters (300 yards). North is toward the top. 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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Pine Island Glacier, Antarct
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These two images of Pine Isl
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4/3/01
| Date |
4/3/01 |
| Description |
These two images of Pine Island Glacier in Antarctica show the recently discovered 25-kilometer (15-mile) long crack that scientists expect will turn into a large iceberg within the next 18 months. The views from NASA's Multi-angle Imaging SpectroRadiometer (MISR) on the Terra satellite also reveal differences in the ice sheet's surface texture, highlighting surface fractures and enabling distinction of rough crevasses from smooth blue ice. The image data shown was acquired on December 12, 2000, during Terra orbit 5246. At left is a conventional, true-color image from the downward-looking (nadir) camera. The false-color image at right is a composite of red-band data taken by the MISR forward 60-degree, nadir, and aftward 60-degree cameras, displayed in red, green and blue, respectively. Color variations in the true-color image at left highlight spectral differences. In the multi-angle composite, on the other hand, color variations act as a proxy for differences in the angular reflectance properties of the scene. In this representation, clouds show up as light purple. Blue to orange gradations on the surface indicate a transition in ice texture from smooth to rough. For example, the bright orange carrot-like features are rough crevasses on the glacier's tongue. In the conventional nadir view, the blue ice labeled "rough crevasses"' and "smooth blue ice" are similarly colored, but the multi-angle composite reveals their different textures, with the smoother ice appearing dark purple instead of orange. This could be an indicator of different mechanisms by which this ice is exposed. The multi-angle view also reveals subtle roughness variations on the frozen sea ice between the glacier and the open water in Pine Island Bay. To the left of the 'icebergs' label are chunks of floating ice. Smaller icebergs embedded in the frozen sea ice are visible below and to the right of the label. These small icebergs are associated with dark streaks. Analysis of the illumination geometry suggests that these streaks are surface features, not shadows. Wind-driven motion and thinning of the sea ice in the vicinity of the icebergs are a possible explanation. Recently, Robert Bindschadler, a glaciologist at the NASA Goddard Space Flight Center discovered in Landsat 7 imagery a newly-formed crack traversing the Pine Island Glacier. This crack is visible as an off-vertical dark line in the MISR nadir view. In the multi-angle composite, the crack and other stress fractures show up very clearly in bright orange. Radar observations of Pine Island Glacier in the 1990's showed the glacier to be shrinking, and the newly discovered crack is expected to eventually lead to the calving of a major iceberg. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calf., for NASA's Office of Earth Science, Washington, D.C. 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/JPL/GSFC/LaRC, MISR Team ##### |
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Home Reef Reborn
| title |
Home Reef Reborn |
| description |
In the South Pacific, south of Late Island along the Tofua volcanic arc in Tonga, the volcanic island Home Reef is being re-born. The island is thought to have emerged after a volcanic eruption in mid-August that also spewed large amounts of floating pumice into Tongan waters and swept across to Fiji about 350 km (220 miles) to the west of where the new island formed. In 2004, a similar eruption created an ephemeral island about 0.5 by 1.5 km (0.3 by 0.9 miles) in size, it was no longer visible in an ASTER image acquired November 2005. This simulated natural color image shows the vegetation-covered stratovolcanic island of Late Island in the upper right. Home Reef is found in the lower left. The two bluish plumes are hot seawater that is laden with volcanic ash and chemicals, the larger one can be traced for more than 14 km (8.4 miles) to the east. The image was acquired Oct. 10, 2006 and covers an area of 24.3 by 30.2 km. It is located at 18.9 degrees south latitude, 174.7 degrees west longitude. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitors the changing surface of our planet. It is one of five Earth-observing instruments launched Dec. 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Image credit: NASA/GSFC/METI/ERSDAC/JAROS and U.S./Japan ASTER Science Team |
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Pine Island Glacier Calving
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| Title |
Pine Island Glacier Calving (WMS) |
| Abstract |
The Pine Island Glacier is the largest discharger of ice in Antarctica and the continent's fastest moving glacier. Even so, when a large crack formed across the glacier in mid 2000, it was surprising how fast the crack expanded, 15 meters per day, and how soon the resulting iceberg broke off, mid-November, 2001. This iceberg, called B-21, is 42 kilometers by 17 kilometers and contains seven years of glacier outflow released to the sea in a single event. This series of images from the MISR instrument on the Terra satellite not only shows the crack expanding and the iceberg breakoff, but the seaward moving glacial flow in the parts of the Pine Island Glacier upstream of the crack. |
| Completed |
2005-03-09 |
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Floods in Gonaives, Haiti
| Title |
Floods in Gonaives, Haiti |
| Description |
The floods that claimed the lives of at least 1,500 Haitians and left as many missing, also filled a large lake basin outside of Gonaives. The basin, which was a dry dust bowl on August 8, 2001, was still completely covered with water on October 3, 2004, two weeks after Hurricane Jeanne's heavy rains induced the flooding. Some of the water may have been present before the floods, but the recent influx of water has pushed the lake far beyond its shores. According to the Associated Press, the lake has covered the primary road connecting Gonaives to Haiti's capital, Port-au-Prince, with over a meter (four feet) of water, making food delivery difficult. The road can be seen here, a blurred white line under the dark blue water. The grey area at the end of the road near the shore is Gonaives. These images were acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]). They were made by combining the infrared, near infrared, and red wavelengths (ASTER bands 4, 3, & 2). In this treatment, bare land appears pink, healthy croplands are light green, and concrete structures such as city buildings have a grey or deep purple tone. NASA image created by Jesse Allen, Earth Observatory using data obtained courtesy of the of NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ]. |
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Floods in Gonaives, Haiti
| Title |
Floods in Gonaives, Haiti |
| Description |
The floods that claimed the lives of at least 1,500 Haitians and left as many missing, also filled a large lake basin outside of Gonaives. The basin, which was a dry dust bowl on August 8, 2001, was still completely covered with water on October 3, 2004, two weeks after Hurricane Jeanne's heavy rains induced the flooding. Some of the water may have been present before the floods, but the recent influx of water has pushed the lake far beyond its shores. According to the Associated Press, the lake has covered the primary road connecting Gonaives to Haiti's capital, Port-au-Prince, with over a meter (four feet) of water, making food delivery difficult. The road can be seen here, a blurred white line under the dark blue water. The grey area at the end of the road near the shore is Gonaives. These images were acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]). They were made by combining the infrared, near infrared, and red wavelengths (ASTER bands 4, 3, & 2). In this treatment, bare land appears pink, healthy croplands are light green, and concrete structures such as city buildings have a grey or deep purple tone. NASA image created by Jesse Allen, Earth Observatory using data obtained courtesy of the of NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ]. |
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A Summer View of Russia's Le
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| Title |
A Summer View of Russia's Lena Delta and Olenek River |
| Description |
These views of the Russian Arctic were acquired by NASA's Multi-angle Imaging SpectroRadiometer (MISR) instrument on July 11, 2004. The brief arctic summer had transformed the frozen tundra and the thousands of lakes, channels, and rivers of the Lena Delta into a fertile wetland, and the usual blanket of thick snow had melted from the vast plains and taiga forests. The images show an area in the northern part of the Sakha Republic in eastern Siberia. The Olenek River wends northeast from the bottom of the images to the upper left, and the delta through which the mighty Lena River empties into the Laptev Sea dominate the top portions of the images. Creating accurate maps of vegetation structure is essential for understanding the seasonal exchanges of energy and water at the Earth's surface and for preserving biodiversity. The left-hand image is a natural-color image from MISR's nadir (vertical-viewing) camera, in which the rivers appear murky due to sediment, and photosynthetically active vegetation appears green. The center image is also from MISR's nadir camera, but is a false-color view in which the predominant red color is due to the brightness of vegetation at near-infrared wavelengths. Apart from the Lena Delta, the most photosynthetically active regions are within the lower half of the image and throughout the great stretch of land that curves across the Olenek River.  The relatively barren ranges of the Volyoi Mountains appear as the pale tan-colored area to the right of image center. The right-hand image is a multiangle, false-color view made from the red band data of the 60-degree-backward, nadir, and 60-degree-forward cameras, displayed as red, green and blue, respectively. Water appears blue in this image because sun glint makes smooth, wet surfaces look brighter at the forward camera's view angle. Much of the landscape and many low clouds appear purple because these surfaces are both forward and backward scattering, and clouds that are further from the surface appear in a different spot for each view angle, creating a rainbow-like appearance. The highly vegetated region in the natural-color nadir image exhibits a faint greenish hue in the multi-angle composite. This subtle effect suggests that the nadir camera is observing more of the brighter, underlying surface than the oblique cameras, providing information about the distribution and density of trees and shrubs in this area. The Multiangle Imaging SpectroRadiometer observes the daylit Earth continuously, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ], provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 24273. The panels cover an area of about 230 kilometers x 420 kilometers, and utilize data from blocks 30 to 34 within World Reference System-2 path 134. 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 courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Raytheon/JPL). |
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Floods in Kansas and Missour
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| Title |
Floods in Kansas and Missouri |
| Description |
Floods that started with heavy rain on June 26, 2007, still surrounded parts of Coffeyville, Kansas, on July 9, when the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) flying on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image. Coffeyville was flooded on July 1, when the swollen Verdigris River burst through a levee. Water swamped neighborhoods and businesses, including the Coffeyville Resources Refinery. Though the refinery had been shut down in anticipation of the flooding, it leaked more than 42,000 gallons of crude oil into the Verdigris River, reported the Environment News Service. [ http://www.ens-newswire.com/ens/jul2007/2007-07-03-01.asp ] The Environmental Protection Agency [ http://www.epa.gov/region7/cleanup/coffeyville/index.html ] was coordinating with Coffeyville Resources to clean up the spill and to ensure that oil did not contaminate drinking water downstream. In these false-color images, the city of Coffeeville is silver and white. Vegetation is red, bare earth is pale gray, and water is dark blue. The Coffeyville Resources Refinery is the concentrated mass of silver, accented with large, white circular storage tanks, northeast of the city. In the top image, the refinery is surrounded by a pool of blue flood water. The lower image, taken on May 19, 2007, shows the area in normal conditions. Downstream from the refinery (to the south) is a grid of streets surrounded by plant-covered land. A few clusters of buildings line the larger streets, but few other large buildings are evident in the area, indicating that this is probably a residential neighborhood. Residual oil-tainted water creates traces of dark blue in the eastern half of the neighborhood. Smudges of blue west of the refinery indicate that the river flooded this part of the city as well. Beyond these areas, the flooded river seemed to remain confined behind levees on its flood plain. The high levees resemble dark red walls hemming in defined geometric shapes, which are filled with water in the top image, but are mud-gray in the lower image. Additional flooding along the Verdigris River is shown in the large image. A broader view [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14353 ] of floods in southeastern Kansas is available in the Natural Hazards section of the Earth Observatory. You can download a 15-meter-resolution KMZ file of Coffeyville [ http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/kansas_ast_2007187.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image by Jesse Allen, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. |
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Floods in Kansas and Missour
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| Title |
Floods in Kansas and Missouri |
| Description |
Floods that started with heavy rain on June 26, 2007, still surrounded parts of Coffeyville, Kansas, on July 9, when the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) flying on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image. Coffeyville was flooded on July 1, when the swollen Verdigris River burst through a levee. Water swamped neighborhoods and businesses, including the Coffeyville Resources Refinery. Though the refinery had been shut down in anticipation of the flooding, it leaked more than 42,000 gallons of crude oil into the Verdigris River, reported the Environment News Service. [ http://www.ens-newswire.com/ens/jul2007/2007-07-03-01.asp ] The Environmental Protection Agency [ http://www.epa.gov/region7/cleanup/coffeyville/index.html ] was coordinating with Coffeyville Resources to clean up the spill and to ensure that oil did not contaminate drinking water downstream. In these false-color images, the city of Coffeeville is silver and white. Vegetation is red, bare earth is pale gray, and water is dark blue. The Coffeyville Resources Refinery is the concentrated mass of silver, accented with large, white circular storage tanks, northeast of the city. In the top image, the refinery is surrounded by a pool of blue flood water. The lower image, taken on May 19, 2007, shows the area in normal conditions. Downstream from the refinery (to the south) is a grid of streets surrounded by plant-covered land. A few clusters of buildings line the larger streets, but few other large buildings are evident in the area, indicating that this is probably a residential neighborhood. Residual oil-tainted water creates traces of dark blue in the eastern half of the neighborhood. Smudges of blue west of the refinery indicate that the river flooded this part of the city as well. Beyond these areas, the flooded river seemed to remain confined behind levees on its flood plain. The high levees resemble dark red walls hemming in defined geometric shapes, which are filled with water in the top image, but are mud-gray in the lower image. Additional flooding along the Verdigris River is shown in the large image. A broader view [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14353 ] of floods in southeastern Kansas is available in the Natural Hazards section of the Earth Observatory. You can download a 15-meter-resolution KMZ file of Coffeyville [ http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/kansas_ast_2007187.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image by Jesse Allen, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. |
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Angora Fire
| Title |
Angora Fire |
| Description |
On the weekend of June 23, 2007, a wildfire broke out south of Lake Tahoe, which stretches across the California-Nevada border. By June 28, the Angora Fire [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14323 ] had burned more than 200 homes and forced some 2,000 residents to evacuate, according to The Seattle Times and the Central Valley Business Times. On June 27, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite captured this image of the burn scar left by the Angora fire. The burn scar is dark gray, or charcoal. Water bodies, including the southern tip of Lake Tahoe and Fallen Leaf Lake, are pale silvery blue, the silver color a result of sunlight reflecting off the surface of the water. Vegetation ranges in color from dark to bright green. Streets are light gray, and the customary pattern of meandering residential streets and cul-de-sacs appears throughout the image, including the area that burned. The burn scar shows where the fire obliterated some of the residential areas just east of Fallen Leaf Lake. According to news reports, the U.S. Forest Service had expressed optimism about containing the fire within a week of the outbreak, but a few days after the fire started, it jumped a defense, forcing the evacuation of hundreds more residents. Strong winds that had been forecast for June 27, however, did not materialize, allowing firefighters to regain ground in controlling the blaze. On June 27, authorities hoped that the fire would be completely contained by July 3. According to estimates provided in the daily report from the National Interagency Fire Center, [ http://www.nifc.gov/information.html ] the fire had burned 3,100 acres (about 12.5 square kilometers) and was about 55 percent contained as of June 28. Some mandatory evacuations remained in effect. You can download a 15-meter-resolution KMZ file of the Angora fire [ http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/tahoe_ast_2007178.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image by Jesse Allen, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. |
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Ash Plume from Karymsky
| Title |
Ash Plume from Karymsky |
| Description |
The Karymsky Volcano in far northeastern Russia had been erupting several times a day for about a week prior to emitting this ash plume on June 19, 2006. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured this false-color image. In this picture, red indicates vegetation, which is lush around the volcano but very sparse on its slopes. The water of Karymskoye Lake appears in blue. The volcano's barren sides are dark gray, and the volcanic plume and nearby haze appear in white or gray. Karymsky Volcano is the most active volcano in the eastern volcanic zone of the Kamchatka Peninsula. The volcano is composed of alternating layers of hardened lava, ash, and rocks. Historical eruptions have involved explosive eruptions of lava fragments and the release of volcanic gases. At the time of the June 19 eruption, Karymsky had an alert status of orange, indicating that a small ash eruption was expected or confirmed, but not likely to exceed an altitude greater than 7,620 meters (25,000 feet) above sea level. NASA image created by Jesse Allen, Earth Observatory, using expedited ASTER data provided the NASA/GSFC/MITI/ERSDAC/JAROS and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Bockfjorden
| Title |
Bockfjorden |
| Description |
Far north within the Arctic Circle off the northern coast of Norway lies a small chain of islands known as Svalbard. These craggy islands have been scoured into shape by ice and sea. The effect of glacial activity can be seen in this image of the northern tip of the island of Spitsbergen. Here, glaciers have carved out a fjord, a U-shaped valley that has been flooded with sea water. Called Bockfjorden, the fjord is located at almost 80 degrees north, and it is still being affected by glaciers. The effect is most obvious in this image in the tan layer of silty freshwater that floats atop the denser blue water of the Arctic Ocean. The fresh water melts off land-bound glaciers and flows over the sandstone, collecting fine red-toned silt. In this image, the tan-colored fresh water flows northward up the fjord and is being pushed to the east side of the fjord by the rotation of the Earth. Glaciers here and elsewhere on Spitsbergen are cold bottom glaciers, which means that they are frozen to the ground rather than floating on top of a thin layer of melt water. The glaciers are also land glaciers since their terminus (end) lies on land, rather than floating on the water (a tidewater glacier). Land glaciers grow and retreat slowly, balancing fresh snow with the melting and draining of old ice. Their rate of growth or retreat can be affected by global warming. In most cases, including the glaciers around Bockfjorden, global warming has caused glaciers to retreat from increased melting. On the eastern side of Svalbard, however, glaciers are growing from enhanced snowfall. The reason for this pattern remains only one of many intriguing unanswered questions of Arctic science in the islands. The Advanced Spaceborne Thermal Emission and Reflection Radiometer, (ASTER [ http://asterweb.jpl.nasa.gov/ ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured this false-color image on June 26, 2001. The image was created by combining near-infrared, red, and green wavelenghts (ASTER bands 3, 2, & 1 respectively). NASA image created by Jesse Allen, Earth Observatory, using data obtained from the Goddard Earth Sciences DAAC [ http://daac.gsfc.nasa.gov/ ] courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Breakup of the World's Large
…
| Title |
Breakup of the World's Largest Iceberg |
| Description |
Iceberg B-15A was the largest iceberg in the world (measuring about 11,000 square kilometers) when it broke away from Western Antarctica's Ross Ice Shelf in March 2000. It held that distinction for over three years until splitting into two pieces in early October, 2003. The Multi-angle Imaging SpectroRadiometer (MISR) acquired these views of the new iceberg B-15J (resting against Ross Island) and B-15A (now free to drift into the Southern Ocean) on October 26. Several massive icebergs (including B-15A) had migrated during 2000 and 2001 and ground against Ross Island [ http://www-misr.jpl.nasa.gov/gallery/galhistory/2002_jan_02.html ], forming a barrier that influenced wind and current patterns and altered the regional ecology. The two images provide information on both the spectral and angular reflectance properties of ice types in the region. The left-hand panel is a false-color view from MISR's vertical-viewing (nadir) camera in which near-infrared, red and blue spectral data are displayed as red, green, and blue, respectively. Because of the tendency of water to absorb near-infrared wavelengths, some ice types exhibit an especially bright blue hue in this display. The right-hand panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60 degree forward-viewing, nadir, and 60 degree backward-viewing cameras are displayed as red, green, and blue, respectively. In the southern latitudes, MISR's backward-pointing cameras receive a stronger signal from surfaces that predominantly forward scatter sunlight (these tend to be smooth surfaces), and MISR's forward-pointing cameras receive a stronger signal from surfaces that predominantly backscatter sunlight (these tend to be rougher surfaces). Thus, the colors in this representation highlight textural properties of elements within the scene, with blue tones indicating smoother surfaces and red/orange hues indicating rougher surfaces. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 20511. The panels cover an area of 129 kilometers x 221 kilometers, and utilize data from blocks 153 to 155 within World Reference System-2 path 56. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ]. Text by Clare Averill (Raytheon/JPL). |
|
Breakup of the World's Large
…
| Title |
Breakup of the World's Largest Iceberg |
| Description |
Iceberg B-15A was the largest iceberg in the world (measuring about 11,000 square kilometers) when it broke away from Western Antarctica's Ross Ice Shelf in March 2000. It held that distinction for over three years until splitting into two pieces in early October, 2003. The Multi-angle Imaging SpectroRadiometer (MISR) acquired these views of the new iceberg B-15J (resting against Ross Island) and B-15A (now free to drift into the Southern Ocean) on October 26. Several massive icebergs (including B-15A) had migrated during 2000 and 2001 and ground against Ross Island [ http://www-misr.jpl.nasa.gov/gallery/galhistory/2002_jan_02.html ], forming a barrier that influenced wind and current patterns and altered the regional ecology. The two images provide information on both the spectral and angular reflectance properties of ice types in the region. The left-hand panel is a false-color view from MISR's vertical-viewing (nadir) camera in which near-infrared, red and blue spectral data are displayed as red, green, and blue, respectively. Because of the tendency of water to absorb near-infrared wavelengths, some ice types exhibit an especially bright blue hue in this display. The right-hand panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60 degree forward-viewing, nadir, and 60 degree backward-viewing cameras are displayed as red, green, and blue, respectively. In the southern latitudes, MISR's backward-pointing cameras receive a stronger signal from surfaces that predominantly forward scatter sunlight (these tend to be smooth surfaces), and MISR's forward-pointing cameras receive a stronger signal from surfaces that predominantly backscatter sunlight (these tend to be rougher surfaces). Thus, the colors in this representation highlight textural properties of elements within the scene, with blue tones indicating smoother surfaces and red/orange hues indicating rougher surfaces. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 20511. The panels cover an area of 129 kilometers x 221 kilometers, and utilize data from blocks 153 to 155 within World Reference System-2 path 56. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ]. Text by Clare Averill (Raytheon/JPL). |
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Brins Fire Near Sedona, AZ
| Title |
Brins Fire Near Sedona, AZ |
| Description |
Northeast of Sedona, Arizona, the Brins Fire continued to threaten parts of Oak Creek Canyon on June 23, 2006. This image from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite shows the Brins Fire and the town of Sedona. The image doesn't appear exactly like a digital photo because it uses ASTER's observations of shortwave and near-infrared light to make the burned area stand out from the unburned vegetation. Vegetation appears red, the burn scar appears charcoal, and bare ground or thinly vegetated ground appears tan or yellow. Route 89, sections of which have been closed by the fire, runs in a gray ribbon through Sedona and Oak Creek Canyon. The haze in the scene may be a mixture of smoke and thin clouds. According to reports from the National Interagency Fire Center [ http://www.nifc.gov/nicc ] on June 26, the Brins Fire was threatening residences, commercial structures, endangered species habitat, and the Oak Creek watershed and Scenic Highway. On that date, the agency estimated the fire was 4,222 acres and about 50 percent contained. NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Floods in the Midwestern Uni
…
| Title |
Floods in the Midwestern United States |
| Description |
August 2007 was the wettest month ever recorded for many places in Minnesota, Iowa, and Wisconsin, with rainfall totals ranging from 23.86 inches in Hokah, Minnesota, to 12.79 inches in Winona Dam, Minnesota, said the National Weather Service. [ http://www.crh.noaa.gov/crnews/display_story.php?wfo=arx&storyid=9990&source=0 ] While the entire month was rainy, much of the rain fell on August 18-20, when several thunderstorms rolled across the region. The thunderstorms triggered disastrous flooding in several Midwest communities, including La Crosse, Wisconsin. A little over 10 inches of rain fell in La Crosse in the 24-hour period that spanned August 18 and August 19, and flash floods resulted. Combined with rains from the rest of August, this rainfall let La Crosse set a new monthly precipitation record of 17 inches. By August 27, when the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image, the floods had largely retreated, though visible signs of flooding remained. Compared to the lower image, acquired on September 7, 2006, the landscape to the west of the Mississippi River is pocked with pools of water. The city of La Crosse, the bright white and gray grid on the east side of the river, appears to have dried out. The city appears much as it did nearly a year earlier with no visible sign of flooding. You can download a 15-meter-resolution KMZ file of the 2007 image of La Crosse [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Sep2007/lacrosse_ast_2007239.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Floods in the Midwestern Uni
…
| Title |
Floods in the Midwestern United States |
| Description |
August 2007 was the wettest month ever recorded for many places in Minnesota, Iowa, and Wisconsin, with rainfall totals ranging from 23.86 inches in Hokah, Minnesota, to 12.79 inches in Winona Dam, Minnesota, said the National Weather Service. [ http://www.crh.noaa.gov/crnews/display_story.php?wfo=arx&storyid=9990&source=0 ] While the entire month was rainy, much of the rain fell on August 18-20, when several thunderstorms rolled across the region. The thunderstorms triggered disastrous flooding in several Midwest communities, including La Crosse, Wisconsin. A little over 10 inches of rain fell in La Crosse in the 24-hour period that spanned August 18 and August 19, and flash floods resulted. Combined with rains from the rest of August, this rainfall let La Crosse set a new monthly precipitation record of 17 inches. By August 27, when the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image, the floods had largely retreated, though visible signs of flooding remained. Compared to the lower image, acquired on September 7, 2006, the landscape to the west of the Mississippi River is pocked with pools of water. The city of La Crosse, the bright white and gray grid on the east side of the river, appears to have dried out. The city appears much as it did nearly a year earlier with no visible sign of flooding. You can download a 15-meter-resolution KMZ file of the 2007 image of La Crosse [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Sep2007/lacrosse_ast_2007239.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Central Pyrenees
| Title |
Central Pyrenees |
| Description |
The Alps may be more famous, but the Pyrenees have been around much longer—tens of millions of years longer, in fact. These mountains formed between 100 and 150 million years ago when the landmass that Spain occupies pushed into the one that France occupies. The mountains have served as a natural barrier between the Iberian Peninsula (Spain and Portugal) and the rest of Europe ever since. Stretching east to west across 430 square kilometers (267 miles), the Pyrenees fall mostly within Spain's borders, but also pass into the independent state of Andorra. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA 's Terra [ http://terra.nasa.gov ] satellite captured this image of part of the Central Pyrenees—the highest part of the range—on August 1, 2000. In this false-color image, clouds appear white, snow appears pale blue, vegetation appears green, and bare ground appears as either pink or dark, bluish-purple. Water on the ground appears dark blue (or nearly black). In this shot, the vegetated areas are mostly to the north, and the peaks to the south are mostly bare rock. In the large image, patches of dark purple that are visible along rivers and in valley floors are probably developed areas. As mountain peaks rise higher, the land they support rises above the treeline (the topmost elevation where trees can grow). At even higher altitudes, hardly any plants can survive at all, so the highest mountain peaks show just snow or bare rock. This mountain chain owes its ruggedness to granite, a volcanic rock that erodes slowly. The mountains also contain other rocks: gneiss and limestone. Glaciers didn't act on the Pyrenees as extensively as they did on the Alps, so these mountains don't sport big lakes left behind by glaciers. They do have water, however, including many small lakes and waterfalls. NASA image created by Jesse Allen, Earth Observatory, using ASTER data made available by NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Chiliques Volcano, Chile
| Title |
Chiliques Volcano, Chile |
| Description |
The Chiliques volcano, which hasn't erupted in at least 10,000 years, is now showing signs of life. This pair of images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) shows the volcano in visible and nrea-infrared light (top) and thermal infrared (lower). The thermal infrared image shows hot spots in the summit crtaer caused by magma just under the surface. For more information, read: Dormant Volcanoes Shows Signs of Life [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www.jpl.nasa.gov/images/earth/volcano/index.html ] Image courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://asterweb.jpl.nasa.gov/ ] |
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Chiliques Volcano, Chile
| Title |
Chiliques Volcano, Chile |
| Description |
The Chiliques volcano, which hasn't erupted in at least 10,000 years, is now showing signs of life. This pair of images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) shows the volcano in visible and nrea-infrared light (top) and thermal infrared (lower). The thermal infrared image shows hot spots in the summit crtaer caused by magma just under the surface. For more information, read: Dormant Volcanoes Shows Signs of Life [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www.jpl.nasa.gov/images/earth/volcano/index.html ] Image courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://asterweb.jpl.nasa.gov/ ] |
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Cloud Heights of Frances and
…
| Title |
Cloud Heights of Frances and Ivan |
| Description |
NASA's Multi-angle Imaging SpectroRadiometer [ http://www-misr.jpl.nasa.gov ] (MISR) captured these images and cloud-top height retrievals of Hurricane Frances on September 4, 2004, when the eye sat just off the coast of eastern Florida, and Hurricane Ivan on September 5, after the storm had devastated Grenada and was heading toward the central and western Caribbean. Hurricane Frances made landfall in the early hours of September 5, and was downgraded to Tropical Storm status as it swept inland through the Florida panhandle and continued northward. Following on the heels of Frances is Hurricane Ivan, which is on record as the strongest tropical hurricane to form at such a low latitude in the Atlantic, and was the most powerful storm to have hit the Caribbean in nearly a decade. The ability of forecasters to predict the intensity and amount of rainfall associated with hurricanes still requires improvement, especially on the 24- to 48-hour timescale vital for disaster planning. To improve the operational models used to make hurricane forecasts, scientists need to better understand the multi-scale interactions at the cloud, mesoscale and synoptic scales that lead to hurricane intensification and dissipation, as well as the various physical processes that determine hurricane intensity and rainfall distributions. Because these uncertainties with regard to how to represent cloud processes still exist, it is vital that the model findings be evaluated against hurricane observations whenever possible. Two-dimensional maps of cloud height such as those shown here offer an unprecedented opportunity for comparing simulated cloud fields against actual hurricane observations. The lefthand panel in each image pair is a natural-color view from MISR's nadir camera. The righthand panels are cloud-top height retrievals produced by automated computer recognition of the distinctive spatial features between images acquired at different view angles. These results indicate that at the time that these images were acquired, clouds within Frances and Ivan had attained altitudes of 15-16 kilometers (9-10 miles) above sea level, respectively. The height fields pictured here are uncorrected for the effects of cloud motion. Wind-corrected heights (which have higher accuracy but coarser spatial coverage) are within about 1 kilometer of the heights shown here. (Visit the Earth Observatory's Natural Hazards Severe Storms [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?topic=storm ] section to view more recent images of Hurricanes Ivan and Frances.) The MISR observes the daylit Earth continuously and every 9 days views the entire globe between 82° north and 82° south latitude. These data products were generated from a portion of the imagery acquired during Terra [ http://terra.nasa.gov ], orbits 25081 and 25094. The panels cover an area of 380 kilometers x 924 kilometers, and utilize data from within blocks 65 to 87 within World Reference System-2 paths 14 and 222, respectively. 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. NASA image courtesy GSFC/LaRC/JPL, MISR Team. [ http://www-misr.jpl.nasa.gov ] Text acknowledgment: Clare Averill (Raytheon/Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign). |
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Grassfire in Iceland
| Title |
Grassfire in Iceland |
| Description |
At the end of March 2006, a grassfire broke out in western Iceland, perhaps as a result of a smoldering cigarette butt. Although this area near the coast to the northwest of the country's capital, Reykjavik, is typically very wet, a period of persistent north winds dried out the grass and made it flammable. The fire burned for several days, threatening farms and livestock and resulting in Iceland's largest fire in its recorded history. This image from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite was captured on April 6, 2006. The burned area appears as a large brownish-charcoal splotch in the center of the image. The fire started inland and burned all the way to the coast. This is a false-color image, and unburned vegetation appears red, clouds appear white, and the Atlantic Ocean (image left) appears nearly black. Several partially ice-covered lakes are scattered across the burned landscape, these lakes appear light blue. NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov ] |
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Gravity Waves Ripple over Ma
…
| Title |
Gravity Waves Ripple over Marine Stratocumulus Clouds |
| Description |
In this natural-color image from the Multi-angle Imaging SpectroRadiometer (MISR), a fingerprint-like gravity wave feature occurs over a deck of marine stratocumulus clouds. Similar to the ripples that occur when a pebble is thrown into a still pond, such "gravity waves" sometimes appear when the relatively stable and stratified air masses associated with stratocumulus cloud layers are disturbed by a vertical trigger from the underlying terrain, or by a thunderstorm updraft or some other vertical wind shear. The stratocumulus cellular clouds that underlie the wave feature are associated with sinking air that is strongly cooled at the level of the cloud-tops—such clouds are common over mid-latitude oceans when the air is unperturbed by cyclonic or frontal activity. This image is centered over the Indian Ocean (at about 38.9° South, 80.6° East), and was acquired on October 29, 2003. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82° north and 82° south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 20545. The image covers an area of 245 kilometers x 378 kilometers, and uses data from blocks 121 to 122 within World Reference System-2 path 134. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Raytheon/JPL). |
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Day Fire in Southern Califor
…
| Title |
Day Fire in Southern California |
| Description |
While the outline of a fire may be hidden by thick smoke in a photo-like, "natural-color" image, "false-color" images that use visible as well as short-wave or near-infrared light observed by remote-sensing instruments can reveal details on the ground. This pair of images shows the Day Fire in southern California northwest of Los Angeles on September 19, 2006. The images are based on data collected by an aircraft-based sensor called MASTER, [ http://masterweb.jpl.nasa.gov/ ] a simulator for two sensors on NASA's Terra [ http://terra.nasa.gov ] satellite. (NASA uses airborne simulators to cross-check the accuracy of satellite data.) In the natural-color version (bottom), dingy white smoke hangs over most of the scene, hiding the outline of the fire. But in the infrared-enhanced version (top), the actively burning areas around the perimeter of the blaze are obvious as glowing pink and yellow spots, while the smoke fades into a transparent blue. Unburned vegetation appears green, while the burned area appears in shades of brown and gold. The MASTER instrument simulates the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensors on Terra. The instrument can be mounted on several different aircraft, including NASA's ER-2 [ http://www.nasa.gov/centers/dryden/news/FactSheets/FS-046-DFRC.html ] and WB-57 [ http://jsc-aircraft-ops.jsc.nasa.gov/wb57/index.html ] airplanes. NASA images created by Jesse Allen, Earth Observatory, using data provided by the ER-2/MASTER team. |
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Day Fire in Southern Califor
…
| Title |
Day Fire in Southern California |
| Description |
While the outline of a fire may be hidden by thick smoke in a photo-like, "natural-color" image, "false-color" images that use visible as well as short-wave or near-infrared light observed by remote-sensing instruments can reveal details on the ground. This pair of images shows the Day Fire in southern California northwest of Los Angeles on September 19, 2006. The images are based on data collected by an aircraft-based sensor called MASTER, [ http://masterweb.jpl.nasa.gov/ ] a simulator for two sensors on NASA's Terra [ http://terra.nasa.gov ] satellite. (NASA uses airborne simulators to cross-check the accuracy of satellite data.) In the natural-color version (bottom), dingy white smoke hangs over most of the scene, hiding the outline of the fire. But in the infrared-enhanced version (top), the actively burning areas around the perimeter of the blaze are obvious as glowing pink and yellow spots, while the smoke fades into a transparent blue. Unburned vegetation appears green, while the burned area appears in shades of brown and gold. The MASTER instrument simulates the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensors on Terra. The instrument can be mounted on several different aircraft, including NASA's ER-2 [ http://www.nasa.gov/centers/dryden/news/FactSheets/FS-046-DFRC.html ] and WB-57 [ http://jsc-aircraft-ops.jsc.nasa.gov/wb57/index.html ] airplanes. NASA images created by Jesse Allen, Earth Observatory, using data provided by the ER-2/MASTER team. |
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Dewatering Effects from the
…
| Title |
Dewatering Effects from the Gujarat Earthquake |
| Description |
MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. This data product was generated from a portion of the imagery acquired during Terra orbits 5736 and 5969. The full-size images cover an area of 215 kilometers x 156 kilometers, and utilize data from blocks 71 to 72 within World Reference System-2 path 151. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Acro Service Corporation/JPL) and David J. Diner (JPL)., browse image of orbit 5969 (380 KB JPEG) On January 26, 2001, when India's Republic Day is normally celebrated, a devastating earthquake hit the state of Gujarat. About 20,000 people died and millions were injured throughout the region. The earthquake had a magnitude of 7.7 on the Richter scale. After the earthquake, local residents reported a mixture of water and sediments fountaining from the Earth. These effects, referred to as dewatering, can result from intense ground shaking by strong earthquakes in regions with shallow water tables. Scientists initially observed dewatering in parts of the Rann of Kutch (a large salt pan in northern Gujarat), and in areas close to the earthquake epicenter. Recent research utilizes the unique capabilities of the Multi-angle Imaging SpectroRadiometer (MISR) instrument to observe earthquake-related dewatering over a broader area (related story: NASA Satellite Helps Scientists See Effects of Earthquakes in Remote Areas [ http://earthobservatory.nasa.gov/Newsroom/NasaNews/2003/2003020511146.html ]). This research is published in the February 4, 2003, issue of EOS Transactions of the American Geophysical Union. These two false-color MISR images were acquired before and after the event, on January 15 and 31, respectively. The earthquake epicenter was located about 80 kilometers east of the city of Bhuj, situated in the lower part of the images. The later image depicts numerous areas where groundwater flowed up to the surface, including within the Rann of Kutch, as well as near the Indo-Pakistani border. These regions of earthquake-associated surface water are apparent up to 200 kilometers from the earthquake's epicenter. Water was observed in many remote areas, especially near the Indo-Pakistani border, which were not easily accessible to survey teams on the ground. Changes in reflection at different view angles and in the near-infrared spectral region assist with the identification of surface water, which appears here in shades of blue and purple. In these visualizations, data from the red band of MISR's most obliquely backward and forward-viewing cameras are displayed as red and blue, respectively, and data from the near-infrared band of MISR's vertically-downward viewing (nadir) camera are displayed as green. Water bodies tend to be more absorbing in the near-infrared, and to be brighter in the view acquired by the more sun-facing (in this case, the 70-degree forward) camera. This combination enhances the ability to distinguish wet surfaces. True color and multi-angle visualizations [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=4810 ] of these data were also released in April 2001. 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. The |
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Dewatering Effects from the
…
| Title |
Dewatering Effects from the Gujarat Earthquake |
| Description |
MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. This data product was generated from a portion of the imagery acquired during Terra orbits 5736 and 5969. The full-size images cover an area of 215 kilometers x 156 kilometers, and utilize data from blocks 71 to 72 within World Reference System-2 path 151. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Acro Service Corporation/JPL) and David J. Diner (JPL)., browse image of orbit 5969 (380 KB JPEG) On January 26, 2001, when India's Republic Day is normally celebrated, a devastating earthquake hit the state of Gujarat. About 20,000 people died and millions were injured throughout the region. The earthquake had a magnitude of 7.7 on the Richter scale. After the earthquake, local residents reported a mixture of water and sediments fountaining from the Earth. These effects, referred to as dewatering, can result from intense ground shaking by strong earthquakes in regions with shallow water tables. Scientists initially observed dewatering in parts of the Rann of Kutch (a large salt pan in northern Gujarat), and in areas close to the earthquake epicenter. Recent research utilizes the unique capabilities of the Multi-angle Imaging SpectroRadiometer (MISR) instrument to observe earthquake-related dewatering over a broader area (related story: NASA Satellite Helps Scientists See Effects of Earthquakes in Remote Areas [ http://earthobservatory.nasa.gov/Newsroom/NasaNews/2003/2003020511146.html ]). This research is published in the February 4, 2003, issue of EOS Transactions of the American Geophysical Union. These two false-color MISR images were acquired before and after the event, on January 15 and 31, respectively. The earthquake epicenter was located about 80 kilometers east of the city of Bhuj, situated in the lower part of the images. The later image depicts numerous areas where groundwater flowed up to the surface, including within the Rann of Kutch, as well as near the Indo-Pakistani border. These regions of earthquake-associated surface water are apparent up to 200 kilometers from the earthquake's epicenter. Water was observed in many remote areas, especially near the Indo-Pakistani border, which were not easily accessible to survey teams on the ground. Changes in reflection at different view angles and in the near-infrared spectral region assist with the identification of surface water, which appears here in shades of blue and purple. In these visualizations, data from the red band of MISR's most obliquely backward and forward-viewing cameras are displayed as red and blue, respectively, and data from the near-infrared band of MISR's vertically-downward viewing (nadir) camera are displayed as green. Water bodies tend to be more absorbing in the near-infrared, and to be brighter in the view acquired by the more sun-facing (in this case, the 70-degree forward) camera. This combination enhances the ability to distinguish wet surfaces. True color and multi-angle visualizations [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=4810 ] of these data were also released in April 2001. 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. The |
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Diverse Terrain of Iran's Da
…
| Title |
Diverse Terrain of Iran's Dasht-e Lut |
| Description |
Roughly 480 by 320 kilometers (300 by 200 miles), Dasht-e Lut is a large salt desert in southeastern Iran. The desert fills a low basin that stretches southward from the Khorasan province into the Kerman province. Although the entire salt desert has just one name, it has more than one appearance. These natural-color images, captured by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite show landscapes so different, one can scarcely imagine they come from the same part of the world, let alone the same desert basin. The picture on the left shows part of the central portion of Dasht-e Lut. The strong diagonal lines result from wind erosion that has carved deep troughs and sharp ridges into the landscape. These wind-sculpted ridges are known as yardangs, and geologic research [ http://disc.gsfc.nasa.gov/geomorphology/GEO_8/GEO_PLATE_E-19.HTML ] has determined that Iran contains some of the world's largest yardangs. ASTER acquired this image on May 13, 2006. The picture on the right shows part of the southeastern portion of Dasht-e Lut. This area consists of sand, and it contains some of the world's tallest dunes, some reaching a height of 300 meters (1,000 feet). In this image, the white areas are saltpans—the aftermath of water that drained into the basins among the dunes and later evaporated. Golden dunes make swirling pattenrs across the image, becoming less tightly packed in the bottom of the scene. ASTER acquired this image on July 17, 2003. Dasht-e Lut's dramatic landscapes are a popular remote-sensing target. Astronauts on the International Space Station photographed [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17226 ] salt lakes from Dasht-e Lut and nearby faulted rocks on February 28, 2006. NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Diverse Terrain of Iran's Da
…
| Title |
Diverse Terrain of Iran's Dasht-e Lut |
| Description |
Roughly 480 by 320 kilometers (300 by 200 miles), Dasht-e Lut is a large salt desert in southeastern Iran. The desert fills a low basin that stretches southward from the Khorasan province into the Kerman province. Although the entire salt desert has just one name, it has more than one appearance. These natural-color images, captured by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite show landscapes so different, one can scarcely imagine they come from the same part of the world, let alone the same desert basin. The picture on the left shows part of the central portion of Dasht-e Lut. The strong diagonal lines result from wind erosion that has carved deep troughs and sharp ridges into the landscape. These wind-sculpted ridges are known as yardangs, and geologic research [ http://disc.gsfc.nasa.gov/geomorphology/GEO_8/GEO_PLATE_E-19.HTML ] has determined that Iran contains some of the world's largest yardangs. ASTER acquired this image on May 13, 2006. The picture on the right shows part of the southeastern portion of Dasht-e Lut. This area consists of sand, and it contains some of the world's tallest dunes, some reaching a height of 300 meters (1,000 feet). In this image, the white areas are saltpans—the aftermath of water that drained into the basins among the dunes and later evaporated. Golden dunes make swirling pattenrs across the image, becoming less tightly packed in the bottom of the scene. ASTER acquired this image on July 17, 2003. Dasht-e Lut's dramatic landscapes are a popular remote-sensing target. Astronauts on the International Space Station photographed [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17226 ] salt lakes from Dasht-e Lut and nearby faulted rocks on February 28, 2006. NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Diverse Terrain of Iran's Da
…
| Title |
Diverse Terrain of Iran's Dasht-e Lut |
| Description |
Roughly 480 by 320 kilometers (300 by 200 miles), Dasht-e Lut is a large salt desert in southeastern Iran. The desert fills a low basin that stretches southward from the Khorasan province into the Kerman province. Although the entire salt desert has just one name, it has more than one appearance. These natural-color images, captured by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite show landscapes so different, one can scarcely imagine they come from the same part of the world, let alone the same desert basin. The picture on the left shows part of the central portion of Dasht-e Lut. The strong diagonal lines result from wind erosion that has carved deep troughs and sharp ridges into the landscape. These wind-sculpted ridges are known as yardangs, and geologic research [ http://disc.gsfc.nasa.gov/geomorphology/GEO_8/GEO_PLATE_E-19.HTML ] has determined that Iran contains some of the world's largest yardangs. ASTER acquired this image on May 13, 2006. The picture on the right shows part of the southeastern portion of Dasht-e Lut. This area consists of sand, and it contains some of the world's tallest dunes, some reaching a height of 300 meters (1,000 feet). In this image, the white areas are saltpans—the aftermath of water that drained into the basins among the dunes and later evaporated. Golden dunes make swirling pattenrs across the image, becoming less tightly packed in the bottom of the scene. ASTER acquired this image on July 17, 2003. Dasht-e Lut's dramatic landscapes are a popular remote-sensing target. Astronauts on the International Space Station photographed [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17226 ] salt lakes from Dasht-e Lut and nearby faulted rocks on February 28, 2006. NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
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Heard Island Volcano
| Title |
Heard Island Volcano |
| Description |
Closer to Antarctica than any other major landmass, Heard Island sits in the far southern Indian Ocean two-thirds of the way from Madagascar to Antarctica. At the center of the remote, ice-covered island are the Big Ben massif, a large section of the Earth's crust that has been pushed up into a dense, rocky mountain by tectonic action, and an active volcano, Mawson Peak. The geologic activity that formed these features continues in the form of frequent eruptions from Mawson Peak. The volcano's current phase of activity began in May 2006, and it continued through December 2006, when the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured this image. Made with both infrared and visible light, the image shows signs of volcanic activity on December 8, 2006. A glowing dot of red on Mawson Peak is thought to be a small lava lake in the summit crater. A fresh lava flow extends 700 meters east of the crater, creating a dark blue smudge on the otherwise even field of snow, which is blue-green in this false-color image. The rocky Big Ben Massif south of Mawson Peak similarly wrinkles the surface of the snow, though some of the apparent roughness may actually be icy clouds. Previous volcanic episodes, including those in 2000-2001 and 2003-2004, have lasted about a year. Due to its isolated location, Heard Island is rarely visited, and satellite imagery provides the only regular information on eruptive activity. NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ]. Image interpretation provided by Matt Patrick and Anna Colvin, Michigan Technological University. [ http://www.mtu.edu/ ] |
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Dust Shrouds the Eastern Med
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| Title |
Dust Shrouds the Eastern Mediterranean |
| Description |
On October 18, 2002, a large dust plume extended across countries bordering the eastern Mediterranean Sea. Information on the horizontal and vertical extent of the dust are provided by these views from the Multi-angle Imaging SpectroRadiometer (MISR). The left-hand panel portrays the scene as viewed by the instrument's vertical-viewing (nadir) camera. Here only some of the dust over eastern Syria and southeastern Turkey can be discerned. The dust is much more obvious in the center panel, which is a view from MISR's most steeply forward-looking camera. In addition, this perspective makes shadows cast by clouds onto the dust layer more apparent, providing a visual clue that the dust is at a lower altitude than these clouds. The right-hand panel is an elevation field derived from automated MISR stereoscopic processing, in which the heights of clouds and certain parts of the dust plume are retrieved. Because the stereoscopic approach makes use of features within the images that exhibit spatial contrast, heights for much of the dust plume (as well as the ocean surface) could not be retrieved, and these areas are shown in dark gray. Clouds within the image area are situated between about 2 and 5.5 kilometers above sea level, and the dust is located below most of the cloud, at heights of about 1.5 kilometers or less. When the stereo retrieval determines that a location is at a near-surface altitude, digital terrain elevation data are displayed instead. The highest clouds in this scene appear as the orange and red areas, and mountainous regions are displayed in light blue and green. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 15072. The panels cover an area of about 380 kilometers x 827 kilometers, and utilize data from blocks 58 to 65 within World Reference System-2 path 174. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Acro Service Corporation/Jet Propulsion Laboratory). |
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Dust Shrouds the Eastern Med
…
| Title |
Dust Shrouds the Eastern Mediterranean |
| Description |
On October 18, 2002, a large dust plume extended across countries bordering the eastern Mediterranean Sea. Information on the horizontal and vertical extent of the dust are provided by these views from the Multi-angle Imaging SpectroRadiometer (MISR). The left-hand panel portrays the scene as viewed by the instrument's vertical-viewing (nadir) camera. Here only some of the dust over eastern Syria and southeastern Turkey can be discerned. The dust is much more obvious in the center panel, which is a view from MISR's most steeply forward-looking camera. In addition, this perspective makes shadows cast by clouds onto the dust layer more apparent, providing a visual clue that the dust is at a lower altitude than these clouds. The right-hand panel is an elevation field derived from automated MISR stereoscopic processing, in which the heights of clouds and certain parts of the dust plume are retrieved. Because the stereoscopic approach makes use of features within the images that exhibit spatial contrast, heights for much of the dust plume (as well as the ocean surface) could not be retrieved, and these areas are shown in dark gray. Clouds within the image area are situated between about 2 and 5.5 kilometers above sea level, and the dust is located below most of the cloud, at heights of about 1.5 kilometers or less. When the stereo retrieval determines that a location is at a near-surface altitude, digital terrain elevation data are displayed instead. The highest clouds in this scene appear as the orange and red areas, and mountainous regions are displayed in light blue and green. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ] provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 15072. The panels cover an area of about 380 kilometers x 827 kilometers, and utilize data from blocks 58 to 65 within World Reference System-2 path 174. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Acro Service Corporation/Jet Propulsion Laboratory). |
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Hurricane Katrina
| Title |
Hurricane Katrina |
| Description |
Goddard Space Flight Center, Greenbelt, MD. JPL is managed for NASA by the California Institute of Technology. Images and movie courtesy of NASA/GSFC/LaRC/JPL, MISR Team. Caption details provided by Clare Averill (Raytheon ITSS/Jet Propulsion Laboratory), David J. Diner, Mike Garay and Ralph Kahn (Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign)., MISR stereo-height estimates (not shown here) indicate that the highest clouds reach 18-19 kilometers above the surface of the Earth. The stereo anaglyph shows relative height variations and enhances the appearance of thin clouds, such as those that mark the series of gravity waves north-east of the eyewall. Atmospheric gravity waves are caused by air displacements in an otherwise stable air layer. In this case, the gravity waves are above the hurricane arms in the upper troposphere, and were probably generated as the towering storm updraft tried to push into the stable air between the troposphere and the stratosphere (known as the tropopause). Some of Katrina's cloud tops were about 2 kilometers above the tropopause. Such high "overshooting tops" are also characteristic of strong and rapidly growing storms. The animation progresses from MISR's most forward-pointing camera, which views the scene first, to the most backward-pointing camera, which views the scene last. It was created by aligning the views from all 9 cameras using the high clouds within the eyewall as a reference point. North is at the top. The convective cloud towers, especially those along the eastern sides of the inner and outer eyewalls, attain the highest altitudes and indicate that the storm is strengthening. Those areas that do not exhibit cloud-top convection are clouds experiencing vertical wind shear, and tend to be lower than the towering cloud structures. The vertical and horizontal development of the convective clouds and the formation of an outer ring of growing clouds (referred to as an "eyewall replacement cycle") also indicate rapid strengthening. During this stage of hurricane development, an outer band of clouds may gradually move inward to replace the existing hurricane eyewall, causing the central pressure to increase and weaken the storm in the short term. However, eyewall replacement may sometimes be a forerunner for rapid strengthening in the longer term. This was the case with Hurricane Katrina, whose central pressure increased slightly on Saturday, but then dropped again significantly on Sunday when Katrina became a Category 5 storm. Observing the development of a concentric eyewall at this spatial and temporal resolution is a unique feature of these MISR observations. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously, viewing the entire globe between 82 degrees North and 82 degrees South latitude every nine days. The still images each cover an area of about 827 kilometers by 380 kilometers, and the animation covers an area of about 202 kilometers by 214 kilometers. The data products were generated from a portion of the imagery acquired during Terra orbit 30280 and utilize data from blocks 69 to 74 within World Reference System-2 path 17. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's, This image and animation from NASA's Multi-angle Imaging SpectroRadiometer (MISR) show the strong convective development of Hurricane Katrina on Saturday, August 27, as it moved west through the Gulf of Mexico. Over 7 minutes during which all 9 MISR cameras viewed Katrina, the animation captures the cloud-top sides, the counterclockwise rotation of the eyewall, and the bubbling growth of the towering cloud structures. At this time, Katrina was undergoing rapid development— it had just been upgraded to a Category 3 hurricane, and within 24 hours it would reach Category 5. On Monday morning when the eyewall made landfall over the United States, it was a Category 4 storm. Hurricane Katrina was one of the most powerful and destructive storms on record for the Atlantic Basin. The image above is a false-color view (near-infrared, red, and blue wavelengths of reflected light displayed as red, green and blue) from MISR's nadir (pointing straight down) camera. In the image above, north is up. The high resolution image linked above shows a wider view of this false-color image, with north to the left. The vegetated Alabama coast in the upper left-hand corner in this high-resolution image appears in red hues. The bottom panel in the high-resolution image is a 3-D stereo anaglyph created with red band data from MISR's 70-degree-forward-viewing and 60-degree-forward-viewing cameras, displayed as red and green/blue, respectively. To observe the height variations in 3-D, you will need to use red/blue glasses. [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] |
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Hurricane Katrina
| Title |
Hurricane Katrina |
| Description |
Goddard Space Flight Center, Greenbelt, MD. JPL is managed for NASA by the California Institute of Technology. Images and movie courtesy of NASA/GSFC/LaRC/JPL, MISR Team. Caption details provided by Clare Averill (Raytheon ITSS/Jet Propulsion Laboratory), David J. Diner, Mike Garay and Ralph Kahn (Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign)., MISR stereo-height estimates (not shown here) indicate that the highest clouds reach 18-19 kilometers above the surface of the Earth. The stereo anaglyph shows relative height variations and enhances the appearance of thin clouds, such as those that mark the series of gravity waves north-east of the eyewall. Atmospheric gravity waves are caused by air displacements in an otherwise stable air layer. In this case, the gravity waves are above the hurricane arms in the upper troposphere, and were probably generated as the towering storm updraft tried to push into the stable air between the troposphere and the stratosphere (known as the tropopause). Some of Katrina's cloud tops were about 2 kilometers above the tropopause. Such high "overshooting tops" are also characteristic of strong and rapidly growing storms. The animation progresses from MISR's most forward-pointing camera, which views the scene first, to the most backward-pointing camera, which views the scene last. It was created by aligning the views from all 9 cameras using the high clouds within the eyewall as a reference point. North is at the top. The convective cloud towers, especially those along the eastern sides of the inner and outer eyewalls, attain the highest altitudes and indicate that the storm is strengthening. Those areas that do not exhibit cloud-top convection are clouds experiencing vertical wind shear, and tend to be lower than the towering cloud structures. The vertical and horizontal development of the convective clouds and the formation of an outer ring of growing clouds (referred to as an "eyewall replacement cycle") also indicate rapid strengthening. During this stage of hurricane development, an outer band of clouds may gradually move inward to replace the existing hurricane eyewall, causing the central pressure to increase and weaken the storm in the short term. However, eyewall replacement may sometimes be a forerunner for rapid strengthening in the longer term. This was the case with Hurricane Katrina, whose central pressure increased slightly on Saturday, but then dropped again significantly on Sunday when Katrina became a Category 5 storm. Observing the development of a concentric eyewall at this spatial and temporal resolution is a unique feature of these MISR observations. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously, viewing the entire globe between 82 degrees North and 82 degrees South latitude every nine days. The still images each cover an area of about 827 kilometers by 380 kilometers, and the animation covers an area of about 202 kilometers by 214 kilometers. The data products were generated from a portion of the imagery acquired during Terra orbit 30280 and utilize data from blocks 69 to 74 within World Reference System-2 path 17. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's, This image and animation from NASA's Multi-angle Imaging SpectroRadiometer (MISR) show the strong convective development of Hurricane Katrina on Saturday, August 27, as it moved west through the Gulf of Mexico. Over 7 minutes during which all 9 MISR cameras viewed Katrina, the animation captures the cloud-top sides, the counterclockwise rotation of the eyewall, and the bubbling growth of the towering cloud structures. At this time, Katrina was undergoing rapid development— it had just been upgraded to a Category 3 hurricane, and within 24 hours it would reach Category 5. On Monday morning when the eyewall made landfall over the United States, it was a Category 4 storm. Hurricane Katrina was one of the most powerful and destructive storms on record for the Atlantic Basin. The image above is a false-color view (near-infrared, red, and blue wavelengths of reflected light displayed as red, green and blue) from MISR's nadir (pointing straight down) camera. In the image above, north is up. The high resolution image linked above shows a wider view of this false-color image, with north to the left. The vegetated Alabama coast in the upper left-hand corner in this high-resolution image appears in red hues. The bottom panel in the high-resolution image is a 3-D stereo anaglyph created with red band data from MISR's 70-degree-forward-viewing and 60-degree-forward-viewing cameras, displayed as red and green/blue, respectively. To observe the height variations in 3-D, you will need to use red/blue glasses. [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] |
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Hurricane Katrina
| Title |
Hurricane Katrina |
| Description |
Goddard Space Flight Center, Greenbelt, MD. JPL is managed for NASA by the California Institute of Technology. Images and movie courtesy of NASA/GSFC/LaRC/JPL, MISR Team. Caption details provided by Clare Averill (Raytheon ITSS/Jet Propulsion Laboratory), David J. Diner, Mike Garay and Ralph Kahn (Jet Propulsion Laboratory) and Greg McFarquhar (University of Illinois at Urbana-Champaign)., MISR stereo-height estimates (not shown here) indicate that the highest clouds reach 18-19 kilometers above the surface of the Earth. The stereo anaglyph shows relative height variations and enhances the appearance of thin clouds, such as those that mark the series of gravity waves north-east of the eyewall. Atmospheric gravity waves are caused by air displacements in an otherwise stable air layer. In this case, the gravity waves are above the hurricane arms in the upper troposphere, and were probably generated as the towering storm updraft tried to push into the stable air between the troposphere and the stratosphere (known as the tropopause). Some of Katrina's cloud tops were about 2 kilometers above the tropopause. Such high "overshooting tops" are also characteristic of strong and rapidly growing storms. The animation progresses from MISR's most forward-pointing camera, which views the scene first, to the most backward-pointing camera, which views the scene last. It was created by aligning the views from all 9 cameras using the high clouds within the eyewall as a reference point. North is at the top. The convective cloud towers, especially those along the eastern sides of the inner and outer eyewalls, attain the highest altitudes and indicate that the storm is strengthening. Those areas that do not exhibit cloud-top convection are clouds experiencing vertical wind shear, and tend to be lower than the towering cloud structures. The vertical and horizontal development of the convective clouds and the formation of an outer ring of growing clouds (referred to as an "eyewall replacement cycle") also indicate rapid strengthening. During this stage of hurricane development, an outer band of clouds may gradually move inward to replace the existing hurricane eyewall, causing the central pressure to increase and weaken the storm in the short term. However, eyewall replacement may sometimes be a forerunner for rapid strengthening in the longer term. This was the case with Hurricane Katrina, whose central pressure increased slightly on Saturday, but then dropped again significantly on Sunday when Katrina became a Category 5 storm. Observing the development of a concentric eyewall at this spatial and temporal resolution is a unique feature of these MISR observations. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously, viewing the entire globe between 82 degrees North and 82 degrees South latitude every nine days. The still images each cover an area of about 827 kilometers by 380 kilometers, and the animation covers an area of about 202 kilometers by 214 kilometers. The data products were generated from a portion of the imagery acquired during Terra orbit 30280 and utilize data from blocks 69 to 74 within World Reference System-2 path 17. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, DC. The Terra satellite is managed by NASA's, This image and animation from NASA's Multi-angle Imaging SpectroRadiometer (MISR) show the strong convective development of Hurricane Katrina on Saturday, August 27, as it moved west through the Gulf of Mexico. Over 7 minutes during which all 9 MISR cameras viewed Katrina, the animation captures the cloud-top sides, the counterclockwise rotation of the eyewall, and the bubbling growth of the towering cloud structures. At this time, Katrina was undergoing rapid development— it had just been upgraded to a Category 3 hurricane, and within 24 hours it would reach Category 5. On Monday morning when the eyewall made landfall over the United States, it was a Category 4 storm. Hurricane Katrina was one of the most powerful and destructive storms on record for the Atlantic Basin. The image above is a false-color view (near-infrared, red, and blue wavelengths of reflected light displayed as red, green and blue) from MISR's nadir (pointing straight down) camera. In the image above, north is up. The high resolution image linked above shows a wider view of this false-color image, with north to the left. The vegetated Alabama coast in the upper left-hand corner in this high-resolution image appears in red hues. The bottom panel in the high-resolution image is a 3-D stereo anaglyph created with red band data from MISR's 70-degree-forward-viewing and 60-degree-forward-viewing cameras, displayed as red and green/blue, respectively. To observe the height variations in 3-D, you will need to use red/blue glasses. [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
Gulf Coast cities weren't the only land surfaces to take a beating from Hurricane Katrina in August 2005. Barrier islands stretching from Texas to Florida were also scoured by the wind and waves of the powerful storm. Permanent changes to the shape and elevation of Timbalier Island and its northeastern companions are visible in this pair of infrared-enhanced images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite. Timbalier Island, the largest island pictured here, sits at the interface between the Gulf of Mexico (south) and Terrebonne Bay (north) along the Louisiana coast southwest of New Orleans. Compared to the image from 2000 (bottom), a large swath of bright sand dominates the eastern side of Timbalier Island in the September 13 image, having either been piled there or exposed by waves and storm surge. To the east-northeast, two small, curving islands have disappeared completely, while farther north, the fierce seas turned two small slots in a barrier island into a single large gap. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
Gulf Coast cities weren't the only land surfaces to take a beating from Hurricane Katrina in August 2005. Barrier islands stretching from Texas to Florida were also scoured by the wind and waves of the powerful storm. Permanent changes to the shape and elevation of Timbalier Island and its northeastern companions are visible in this pair of infrared-enhanced images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite. Timbalier Island, the largest island pictured here, sits at the interface between the Gulf of Mexico (south) and Terrebonne Bay (north) along the Louisiana coast southwest of New Orleans. Compared to the image from 2000 (bottom), a large swath of bright sand dominates the eastern side of Timbalier Island in the September 13 image, having either been piled there or exposed by waves and storm surge. To the east-northeast, two small, curving islands have disappeared completely, while farther north, the fierce seas turned two small slots in a barrier island into a single large gap. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
Gulf Coast cities weren't the only land surfaces to take a beating from Hurricane Katrina in August 2005. Barrier islands stretching from Texas to Florida were also scoured by the wind and waves of the powerful storm. Permanent changes to the shape and elevation of Horn and Petit Bois Islands south of Pascagoula, Mississippi, are visible in these infrared-enhanced images captured by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite. The eastern and western tips of Horn island have been eroded so greatly that they are now below sea level, their white sandy beaches (August 7 image) now covered by blue water (September 17 image). The sound (northern) side of the island is layered with sand, which stands out in grayish-white against the red of vegetation. On Petit Bois Island, the changes appear more subtle, but there, too, the red of the island's vegetation appears softened by bright sand. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
Gulf Coast cities weren't the only land surfaces to take a beating from Hurricane Katrina in August 2005. Barrier islands stretching from Texas to Florida were also scoured by the wind and waves of the powerful storm. Permanent changes to the shape and elevation of Horn and Petit Bois Islands south of Pascagoula, Mississippi, are visible in these infrared-enhanced images captured by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite. The eastern and western tips of Horn island have been eroded so greatly that they are now below sea level, their white sandy beaches (August 7 image) now covered by blue water (September 17 image). The sound (northern) side of the island is layered with sand, which stands out in grayish-white against the red of vegetation. On Petit Bois Island, the changes appear more subtle, but there, too, the red of the island's vegetation appears softened by bright sand. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
A fringe of barrier islands line the coast of Mississippi, protecting the mainland from the pounding waves of most ocean storms, but the islands could not shelter the mainland from Hurricane Katrina's exceptionally powerful storm surge. The battering waves ate away at the islands, permanently altering their shape. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image of East and West Ship Islands and Cat Island on September 8, 2005. The lower image is made up of two difference ASTER scenes. The scene on the left was acquired on June 4, 2005, while the scene on the right was taken on April 22, 2001. A diagonal line where the ocean changes color indicates the division between the two images. The most dramatic change can be seen in East Ship Island. Compared to April 2001, most of East Ship Island has disappeared beneath the ocean by September 8, 2005. Some of the erosion may have occurred in other storms between 2001 and 2005, but Katrina is probably responsible for much of the damage. The ghost shores of the island are faintly visible under the water as a lighter shade of blue. West Ship Island, which hosts a civil war fort and a historic lighthouse, and Cat Island have also shrunk slightly. The southern tip of Cat Island is missing and the pointed tips of Ship Island have been rounded out. The section of the northwestern shore that holds the lighthouse and fort seems to be unchanged. East and West Ship Islands are no strangers to the type of erosion Katrina inflicted on them. The islands had been a single island until Hurricane Camille cleft it in two in 1969. In general, barrier islands are constantly changing, their shorelines building and eroding at remarkable speed, with dramatic change occurring routinely when powerful storms strike. In competition with nature, humans also have a large impact on barrier islands. Such islands are popular vacation spots. Construction can interfere with beach building and can degrade the vegetation that anchors dunes on the islands. Of the barrier islands along the U.S. coast, East Ship Island is one of the few that remains in its natural state, unchanged by population. To preserve the islands, Congress added them to Gulf Islands National Seashore [ http://www.nps.gov/guis/extended/MIS/MNature/Islands.htm ], the United States' largest national seashore, under the National Park Service. Cat Island forms the western boundary of the park, which consists of a string of islands along the Mississippi and Florida coasts, including East and West Ship Island. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
A fringe of barrier islands line the coast of Mississippi, protecting the mainland from the pounding waves of most ocean storms, but the islands could not shelter the mainland from Hurricane Katrina's exceptionally powerful storm surge. The battering waves ate away at the islands, permanently altering their shape. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image of East and West Ship Islands and Cat Island on September 8, 2005. The lower image is made up of two difference ASTER scenes. The scene on the left was acquired on June 4, 2005, while the scene on the right was taken on April 22, 2001. A diagonal line where the ocean changes color indicates the division between the two images. The most dramatic change can be seen in East Ship Island. Compared to April 2001, most of East Ship Island has disappeared beneath the ocean by September 8, 2005. Some of the erosion may have occurred in other storms between 2001 and 2005, but Katrina is probably responsible for much of the damage. The ghost shores of the island are faintly visible under the water as a lighter shade of blue. West Ship Island, which hosts a civil war fort and a historic lighthouse, and Cat Island have also shrunk slightly. The southern tip of Cat Island is missing and the pointed tips of Ship Island have been rounded out. The section of the northwestern shore that holds the lighthouse and fort seems to be unchanged. East and West Ship Islands are no strangers to the type of erosion Katrina inflicted on them. The islands had been a single island until Hurricane Camille cleft it in two in 1969. In general, barrier islands are constantly changing, their shorelines building and eroding at remarkable speed, with dramatic change occurring routinely when powerful storms strike. In competition with nature, humans also have a large impact on barrier islands. Such islands are popular vacation spots. Construction can interfere with beach building and can degrade the vegetation that anchors dunes on the islands. Of the barrier islands along the U.S. coast, East Ship Island is one of the few that remains in its natural state, unchanged by population. To preserve the islands, Congress added them to Gulf Islands National Seashore [ http://www.nps.gov/guis/extended/MIS/MNature/Islands.htm ], the United States' largest national seashore, under the National Park Service. Cat Island forms the western boundary of the park, which consists of a string of islands along the Mississippi and Florida coasts, including East and West Ship Island. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
A fringe of barrier islands line the coast of Mississippi, protecting the mainland from the pounding waves of most ocean storms, but the islands could not shelter the mainland from Hurricane Katrina's exceptionally powerful storm surge. The battering waves ate away at the islands, permanently altering their shape. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image of East and West Ship Islands and Cat Island on September 8, 2005. The lower image is made up of two difference ASTER scenes. The scene on the left was acquired on June 4, 2005, while the scene on the right was taken on April 22, 2001. A diagonal line where the ocean changes color indicates the division between the two images. The most dramatic change can be seen in East Ship Island. Compared to April 2001, most of East Ship Island has disappeared beneath the ocean by September 8, 2005. Some of the erosion may have occurred in other storms between 2001 and 2005, but Katrina is probably responsible for much of the damage. The ghost shores of the island are faintly visible under the water as a lighter shade of blue. West Ship Island, which hosts a civil war fort and a historic lighthouse, and Cat Island have also shrunk slightly. The southern tip of Cat Island is missing and the pointed tips of Ship Island have been rounded out. The section of the northwestern shore that holds the lighthouse and fort seems to be unchanged. East and West Ship Islands are no strangers to the type of erosion Katrina inflicted on them. The islands had been a single island until Hurricane Camille cleft it in two in 1969. In general, barrier islands are constantly changing, their shorelines building and eroding at remarkable speed, with dramatic change occurring routinely when powerful storms strike. In competition with nature, humans also have a large impact on barrier islands. Such islands are popular vacation spots. Construction can interfere with beach building and can degrade the vegetation that anchors dunes on the islands. Of the barrier islands along the U.S. coast, East Ship Island is one of the few that remains in its natural state, unchanged by population. To preserve the islands, Congress added them to Gulf Islands National Seashore [ http://www.nps.gov/guis/extended/MIS/MNature/Islands.htm ], the United States' largest national seashore, under the National Park Service. Cat Island forms the western boundary of the park, which consists of a string of islands along the Mississippi and Florida coasts, including East and West Ship Island. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
Dauphin Island guards the mouth of Mobile Bay, Alabama, from the open waters of the Gulf of Mexico. Though not directly under the eye of the storm, the island was blasted with a powerful storm surge when Hurricane Katrina came ashore on August 29, 2005. When the storm passed, Dauphin Island had been divided in two. On September 10, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image of the permanently altered island. A large inlet has been cut across the island in the same spot that a much smaller inlet existed before the storm. The western tip of the island has also been washed away, though no other changes are obvious. Miraculously, the thin causeway that connects the island to the mainland appears to be intact. In these images, vegetation is red while sand is a brilliant white. Barrier islands are constantly changing with shorelines building and eroding at remarkable speed. The islands are also routinely shaped by powerful storms, sometimes dramatically breaking apart as Dauphin Island broke under Katrina's wrath. Barrier islands often absorb the brunt of a hurricane's storm surge, offering some protection to the mainland shore. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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Hurricane Katrina Erodes the
…
| Title |
Hurricane Katrina Erodes the U.S. Gulf Coast |
| Description |
Dauphin Island guards the mouth of Mobile Bay, Alabama, from the open waters of the Gulf of Mexico. Though not directly under the eye of the storm, the island was blasted with a powerful storm surge when Hurricane Katrina came ashore on August 29, 2005. When the storm passed, Dauphin Island had been divided in two. On September 10, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image of the permanently altered island. A large inlet has been cut across the island in the same spot that a much smaller inlet existed before the storm. The western tip of the island has also been washed away, though no other changes are obvious. Miraculously, the thin causeway that connects the island to the mainland appears to be intact. In these images, vegetation is red while sand is a brilliant white. Barrier islands are constantly changing with shorelines building and eroding at remarkable speed. The islands are also routinely shaped by powerful storms, sometimes dramatically breaking apart as Dauphin Island broke under Katrina's wrath. Barrier islands often absorb the brunt of a hurricane's storm surge, offering some protection to the mainland shore. NASA images courtesy Jesse Allen, Earth Observatory, using data obtained courtesy of the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team [ http://asterweb.jpl.nasa.gov/ ] |
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