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Thunderstorms over Brazil
| Title |
Thunderstorms over Brazil |
| Description |
This photograph, acquired in February 1984 by an astronaut aboard the space shuttle, shows a series of mature thunderstorms located near the Parana River in southern Brazil. With abundant warm temperatures and moisture-laden air in this part of Brazil, large thunderstorms are commonplace. A number of overshooting tops and anvil clouds are visible at the tops of the clouds. Storms of this magnitude can drop large amounts of rainfall in a short period of time, causing flash floods. However, a NASA-funded researcher has discovered that tiny airborne particles of pollution may modify developing thunderclouds by increasing the quantity and reducing the size of the ice crystals within them. These modifications may affect the clouds? impact on the Earth?s ?radiation budget,? or the amount of radiation that enters and leaves our planet. Steven Sherwood, a professor at Yale University, found that airborne aerosols reduce the size of ice crystals in thunderclouds and may reduce precipitation as well. Using several satellites and instruments including NASA?s Total Ozone Mapping Spectrometer (TOMS) and NASA?s Tropical Rainfall Measuring Mission (TRMM) satellite, Sherwood observed how airborne pollution particles (aerosols) affect large thunderstorms, or cumulonimbus clouds in the tropics. Common aerosols include mineral dust, smoke, and sulfates. An increased number of these particles create a larger number of smaller ice crystals in cumulonimbus clouds. As a result of their smaller size, the ice crystals evaporate from a solid state directly into a gas, instead of falling as rain. Sherwood noted that this effect is more prevalent over land than open ocean areas. Previous research by Daniel Rosenfeld of Hebrew University revealed that aerosols and pollution reduced rainfall in shallow cumulus clouds of liquid water, which do not have the capability to produce as much rainfall. Sherwood expanded on that research by looking at cumulonimbus clouds with more ice particles. Studies have also proven that ice particles are smaller in the upper reaches of thunderclouds when there is more pollution and when the rising air in the clouds (convection) is stronger. Aerosols seem to have the most influence on seasonal and longer timescales such as during the warmer months when plants and undergrowth are burned to clear fields. Over areas where biomass burning occurs, such as South America, aerosols have been found to reduce the diameter of ice crystals in the clouds by as much as 20 percent. Areas over deserts, such as Africa's Sahel Region where dust is a primary aerosol, there was a 10 percent decrease in the diameter of ice crystals in cumulonimbus clouds. Aerosol particles are necessary for clouds to form, and it has been suspected that clouds might be altered by large concentrations of them. By looking at ten years of aerosol data and statistically analyzing many thunderclouds, Sherwood was able to confirm that they were affected. Sherwood found that ice, crystals are smaller in clouds over continents than oceans, which could be attributed to the amount of pollution generated over land. The highest values occur widely over Northern Africa, where desert dust and smoke from agricultural burning occur. Intermediate values prevail over much of Asia, through the Indonesia region and into the south Pacific. The largest ice crystal sizes were found over the eastern Pacific and southern Indian Oceans. Sherwood?s article, ?Aerosols and Ice Particle Size in Tropical Cumulonimbus,? appears in the May 1, 2002, issue of the American Meteorological Society "Journal of Climate". This work was performed under the NASA Earth Observing System/Interdisciplinary Science (IDS) program under the Earth Science Enterprise (ESE). Image STS41B-41-2347 [ http://earth.jsc.nasa.gov/photoinfo.cgi?PHOTO=STS41B-41-2347 ] was provided by the Earth Sciences and Image Analysis Laboratory [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eol.jsc.nasa.gov/ ] at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eol.jsc.nasa.gov/sseop/ ] |
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Tsunami Inundation, North of
…
PIA06671
Sol (our sun)
ASTER, SIR-C/X-SAR
| Title |
Tsunami Inundation, North of Phuket, Thailand ASTER Images and SRTM Elevation Model |
| Original Caption Released with Image |
Figure 1 The Indian Ocean coastline north of Phuket, Thailand is a major tourist destination that was in the path of the tsunami produced by a giant offshore earthquake on December 26, 2004. This disaster resulted in a heavy loss of life. These simulated natural color ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) images show a 27 kilometer (17-mile) long stretch of coast 80 kilometers (50 miles) north of the Phuket airport in the Khao Lak area on December 31 (middle) and also two years earlier (left). The changes along the coast are obvious (changing from green to grey) where the vegetation was stripped away by the tsunami. The image on the right is a copy of the later ASTER scene but it includes highlighting in red for areas that have elevations within 10 meters (33 feet) of sea level. This elevation information was supplied by the Shuttle Radar Topography Mission (SRTM). The red areas appear to include most of the tsunami inundated areas. The geographic correspondence of the imaged damage and the highlighted elevation range is quite good in the middle and upper parts of the scene and is consistent with an early field report of about 10 meters of inundation. In the south, the elevation range corresponds to a much wider area than the actual damage, but this is to be expected for areas increasingly far from the coast. Offshore bathymetry (depth variations), coastal landforms, distance from the coast, and additional factors other than elevation range control the damage extent. But elevation measurements along the coast, as provided by SRTM, give a general indication of areas at risk, as now confirmed by ASTER. ASTER images Earth to map and monitor the changing surface of our planet 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). These data provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. ASTER is one of five Earth-observing instruments launched December 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. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour,, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C. Size: 9.75 x 27.6 kilometers (6.0 x 17.1 miles), Location: 8.6 degrees North latitude, 98.3 degrees East longitude Orientation: Top is 8.25 degrees east of North Image Data: ASTER Bands 1, 2, 3 mixed for simulated true color. Date Acquired: November 15, 2002 and December 31, 2004 (ASTER), February 2000 (SRTM) |
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Tsunami Inundation, North of
…
PIA06671
Sol (our sun)
ASTER, SIR-C/X-SAR
| Title |
Tsunami Inundation, North of Phuket, Thailand ASTER Images and SRTM Elevation Model |
| Original Caption Released with Image |
Figure 1 The Indian Ocean coastline north of Phuket, Thailand is a major tourist destination that was in the path of the tsunami produced by a giant offshore earthquake on December 26, 2004. This disaster resulted in a heavy loss of life. These simulated natural color ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) images show a 27 kilometer (17-mile) long stretch of coast 80 kilometers (50 miles) north of the Phuket airport in the Khao Lak area on December 31 (middle) and also two years earlier (left). The changes along the coast are obvious (changing from green to grey) where the vegetation was stripped away by the tsunami. The image on the right is a copy of the later ASTER scene but it includes highlighting in red for areas that have elevations within 10 meters (33 feet) of sea level. This elevation information was supplied by the Shuttle Radar Topography Mission (SRTM). The red areas appear to include most of the tsunami inundated areas. The geographic correspondence of the imaged damage and the highlighted elevation range is quite good in the middle and upper parts of the scene and is consistent with an early field report of about 10 meters of inundation. In the south, the elevation range corresponds to a much wider area than the actual damage, but this is to be expected for areas increasingly far from the coast. Offshore bathymetry (depth variations), coastal landforms, distance from the coast, and additional factors other than elevation range control the damage extent. But elevation measurements along the coast, as provided by SRTM, give a general indication of areas at risk, as now confirmed by ASTER. ASTER images Earth to map and monitor the changing surface of our planet 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). These data provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. ASTER is one of five Earth-observing instruments launched December 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. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour,, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C. Size: 9.75 x 27.6 kilometers (6.0 x 17.1 miles), Location: 8.6 degrees North latitude, 98.3 degrees East longitude Orientation: Top is 8.25 degrees east of North Image Data: ASTER Bands 1, 2, 3 mixed for simulated true color. Date Acquired: November 15, 2002 and December 31, 2004 (ASTER), February 2000 (SRTM) |
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Sulfur Dioxide Plume from Mt
…
PIA09937
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Sulfur Dioxide Plume from Mt. Etna Eruption 2002 as Detected with AIRS Data |
| Original Caption Released with Image |
Mt. Etna, a volcano on the island of Sicily, erupted on October 26, 2002. Preliminary analysis of data taken by the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite on October 28 shows the instrument can provide an excellent means to study the evolution and structure of the sulfur dioxide plume emitted from volcanoes. These data also demonstrate that AIRS can be used to obtain the total mass of sulfur dioxide injected into the atmosphere during a volcanic event, information that may help us to better understand these dangerous natural occurrences in the future. The image clearly shows the sulfur dioxide plume. This image was created by comparing data taken at two different frequencies, or channels, and creating one image that highlights the differences between these two channels. Both channels are sensitive to water vapor, but one of the channels is also sensitive to sulfur dioxide. By subtracting out the common water vapor signal in both channels, the sulfur dioxide feature remains and shows up as an enhancement in the difference image. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena. |
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Perspective View, Mt. Etna,
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PIA03370
Sol (our sun)
ASTER, C-Band Interferometri
…
| Title |
Perspective View, Mt. Etna, Italy & the Aeolian Islands |
| Original Caption Released with Image |
Italy's Mount Etna and the Aeolian Islands are the focus of this perspective view made from an Advanced Spaceborne Thermal and Emission Radiometer (ASTER) image from NASA's Terra spacecraft overlaid on Shuttle Radar Topography Mission (SRTM) topography. The image is looking south with the islands of Lipari and Vulcano in the foreground and Etna with its dark lava flows on the skyline. Vulcano also hosts an active volcano, the cone of which is prominent. In late October 2002, Etna erupted again, sending lava flows down the north and south sides of the volcano. The north flows are near the center of this view, but the ASTER image is from before the eruption. In addition to the terrestrial applications of these data for understanding active volcanoes and hazards associated with them such as lava flows and explosive eruptions, geologists studying Mars find these data useful as an analog to martian landforms and geologic processes. In late September 2002, a field conference with the theme of Terrestrial Analogs to Mars focused on Mount Etna allowing Mars geologists to see in person the types of features they can only sample remotely. Elevation data used in this image was acquired by SRTM aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C. Size: Varies across scene Location: 38.25 degrees North latitude, 15 degrees East longitude Orientation: Looking south Image Data: ASTER bands 2, 3, 1 as red, green, blue, respectively. Original Data Resolution: SRTM 1 arc-second (30 meters or 98 feet) Date Acquired: February 2000 (SRTM), July 29, 2001 (ASTER) |
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Perspective View, Mt. Etna,
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PIA03371
Sol (our sun)
ASTER, C-Band Interferometri
…
| Title |
Perspective View, Mt. Etna, Italy |
| Original Caption Released with Image |
Italy's Mount Etna is the focus of this perspective view made from an Advanced Spaceborne Thermal and Emission Radiometer (ASTER) image from NASA's Terra spacecraft overlaid on Shuttle Radar Topography Mission (SRTM) topography. The image is looking south with dark lava flows from the 1600's (center) to 1981 (long flow at lower right) visible in the foreground and the summit of Etna above. The city of Catania is barely visible behind Etna on the bay at the upper left. In late October 2002, Etna erupted again, sending lava flows down the north and south sides of the volcano. The north flows are near the center of this view, but the ASTER image is from before the eruption. In addition to the terrestrial applications of these data for understanding active volcanoes and hazards associated with them such as lava flows and explosive eruptions, geologists studying Mars find these data useful as an analog to martian landforms and geologic processes. In late September 2002, a field conference with the theme of Terrestrial Analogs to Mars focused on Mount Etna, allowing Mars geologists to see in person the types of features they can only sample remotely. Elevation data used in this image was acquired by SRTM aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C. Size: Varies across scene Location: 38 degrees North latitude, 15.5 degrees East longitude Orientation: Looking south Image Data: ASTER bands 2, 3, 1 as red, green, blue, respectively. Original Data Resolution: SRTM 1 arc-second (30 meters or 98 feet) Date Acquired: February 2000 (SRTM), July 29, 2001 (ASTER) |
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Dongting Lake, China
PIA03858
Sol (our sun)
ASTER
| Title |
Dongting Lake, China |
| Original Caption Released with Image |
These images show dramatic change in the water at Dongting Lake in Hunan province, China. A flood crest surged down the Yangtze River in late August of this year, but the embankments made by residents there held. The left image was acquired on September 2, 2002 and shows the extent of the lake. The right image was obtained March 19, 2002 before the flooding began. These images were acquired on September 2, 2002 and March 19,2002 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. 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 will image Earth for the next 6 years to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 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. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader, Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system. Size: 39.1 x 119.4 km (22.4 x 74.0 miles)Location: 30.1 deg. North lat., 112.9 deg. East long. Orientation: North at top Image Data: ASTER bands 1,2, and 3. Original Data Resolution: 15 mDates Acquired: September 2 and March 19, 2002 |
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Biscuit Fire, OR
PIA03856
Sol (our sun)
ASTER
| Title |
Biscuit Fire, OR |
| Original Caption Released with Image |
In southwest Oregon, the Biscuit Fire continues to grow. This image, acquired from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite on August 14, 2002, shows the pillars of smoke arising from the fires. Active fire areas are in red. More than 6,000 fire personnel are assigned to the Biscuit Fire alone, which was 390,276 acres as of Thursday morning, August 15, and only 26 percent contained. Among the resources threatened are thousands of homes, three nationally designated wild and scenic rivers, and habitat for several categories of plants and animals at risk of extinction. Firefighters currently have no estimate as to when the fire might be contained. 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 will image Earth for the next six years to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 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. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. science team leader, Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long-term research effort to understand and protect our home planet. Size: 45 by 60 kilometers (27.9 by 37.2 miles) Location: 42.1 degrees North latitude, 124.1 degrees West longitude Orientation: North at top Image Data: ASTER bands 1, 2, 3 and 8. Original Data Resolution: 15 and 30 meters (49.2 and 98.4 feet) Date Acquired: August 14, 2002 |
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Hurricane Lili Heads for Lou
…
PIA03728
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Hurricane Lili Heads for Louisiana Landfall |
| Original Caption Released with Image |
Characteristics of a strengthening Category 3 Hurricane Lili are apparent in these images from the Multi-angle Imaging SpectroRadiometer(MISR), including a well-developed clearing at the hurricane eye. When these views were acquired on October 2, 2002, Lili was approaching the Gulf coast of the United States and rapidly strengthening toward Category 4 status. The storm's power reached its peak less than twelve hours later, and although it weakened overnight, this was still a dangerous system as it blew across the Louisiana coast on the morning of October 3. Lili was the first hurricane to make landfall in the United States since Hurricane Irene in 1999. Twenty-eight parishes in Louisiana were declared disaster areas, yet this hurricane fortunately caused much less damage than what could have resulted from an event of this magnitude. The top panel uses data from MISR's vertical-viewing (nadir) camera and data from the red, near-infrared, and blue spectral bands is displayed as red, green and blue to create a false-color view in which land surfaces appear bright green. The nadir and stereo anaglyph views are identical in their band choices, except that the anaglyph uses data from the 26-degree forward-viewing camera for the red band. The images are oriented with north to the left. Observing the spectacular three-dimensional structure of the hurricane eyewall and of convective thunderclouds present in the storm's spiral arms requires the use of red-blue glasses, with the red filter placed over your left eye. Information on ordering glasses can be found here [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ]. 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. These data products were generated from a portion of the imagery acquired during Terra orbit 14844. The panels cover an area of about 380 kilometers x 985 kilometers, and utilize data from blocks 67 to 73within World Reference System-2 path 21. 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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Dust Shrouds the Eastern Med
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PIA03731
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Dust Shrouds the Eastern Mediterranean |
| Original Caption Released with Image |
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. 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. 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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New NASA Imagery Sheds Addit
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PIA07227
Sol (our sun)
ASTER
| Title |
New NASA Imagery Sheds Additional Perspectives on Tsunami |
| Original Caption Released with Image |
The island of Phuket on the Indian Ocean coast of Thailand is a major tourist destination and was also in the path of the tsunami that washed ashore on December 26, 2004, resulting in a heavy loss of life. These simulated natural color ASTER images show a 27 kilometer (17-mile) long stretch of coast north of the Phuket airport on December 31 (right), along with an image acquired two years earlier (left). The changes along the coast are obvious where the vegetation has been stripped away. These images are being used to create damage assessment maps for the U.S. Agency for International Development (USAID) Office of Foreign Disaster Assistance. 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 monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 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. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate. Size: 9.8 by 27.6 kilometers (6.1 by 17.1 miles) Location: 8.6 degrees North latitude, 98.2 degrees East longitude Orientation: North at top Image Data: ASTER bands 3,2, and 1 Original Data Resolution: 15 meters (49.2 feet) Dates Acquired: November 15, 2002, and December 31, 2004 |
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Mt. Etna, Italy
PIA03881
Sol (our sun)
ASTER
| Title |
Mt. Etna, Italy |
| Original Caption Released with Image |
On Sunday, November 3, 2002, Mt. Etna's ash-laden plume was imaged by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. The plume is seen blowing toward the south-southeast, over the city and airport of Catania, Sicily. The previous day, the plume was blowing toward the northwest, and posed no hazard to Catania. The current eruption of Mt. Etna, Europe's most active volcano, began on October 27. These sorts of observations from space may help civil defense authorities mitigate hazards from active eruptions. Space data may also help scientists evaluate the behavior and effects volcanic eruptions have on our global climate system. 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 monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 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. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. science team leader, Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long-term research effort to understand and protect our home planet. Through the study of Earth, NASA will help to provide sound science to policy and economic decision-makers so as to better life here, while developing the technologies needed to explore the universe and search for life beyond our home planet. Size: 50.8 by 76.5 kilometers (31.5 by 47.4 miles) Location: 37.6 degrees North latitude, 15.1 degrees East longitude Orientation: North at top Image Data: ASTER bands 1, 2 and 3 Original Data Resolution: 15 meters (49.2 feet) Date Acquired: November 3, 2002 |
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Average Tropical Relative Hu
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PIA00523
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Average Tropical Relative Humidity from AIRS, Dec-Feb 2002-2005 |
| Original Caption Released with Image |
The average tropospheric relative humidity from AIRS for the four December-February periods during 2002 through 2005. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena. |
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Multi-angle Portrayals of Mt
…
PIA03733
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Multi-angle Portrayals of Mt. Etna's Plume |
| Original Caption Released with Image |
These images from the Multi-angle Imaging SpectroRadiometer (MISR) capture the energetic eruption of Sicily's Mount Etna volcano on October 29, 2002. Viewing Etna's eruptive activities at MISR's multiple observation angles reveals the structure and relative heights of several plumes emanating from the volcano. The image panels are a natural-color view from MISR's vertical-viewing (nadir) camera (top), and a 3D stereo anaglyph (bottom). In the anaglyph, data from the 70-degree and 60-degree forward-looking cameras are displayed as red and green-blue, respectively. (For the 60-degree camera, 275-m red band data were used to spatially "sharpen" the green and blue 1.1-km resolution imagery). With the aid of red-blue glasses, the three-dimensional nature of the ash plume and the relative heights of plume and clouds can be discerned. Glasses should be worn with the red filter placed over your left eye. Information on ordering glasses can be found at http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ]. Also provided is a "fly-over"""animation, which progresses according to the sequence in which the MISR cameras observed this scene. Both the "fly-over" and the stereo anaglyph allow the structure of both the main, dark plume and several lighter-colored plumes to be observed. The animation uses all nine MISR cameras. As the Terra satellite passes overhead, the 70-degree forward-viewing camera views a scene first, followed by the 60, 46 and 26-degree forward-viewing cameras, the nadir camera, and the four backward-viewing cameras. It takes approximately seven minutes for all nine cameras to view an area. 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. These images were generated from a portion of the data acquired during Terra orbit 15233 and have been oriented with north to the left. The still image panels cover an area of about 297 kilometers x 133 kilometers, and utilize data from blocks 60 to 62 within World Reference System-2 path 187. 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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Windswept Shores of the Aral
…
PIA04324
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Windswept Shores of the Aral Sea |
| Original Caption Released with Image |
. The Little Aral Sea is located near the left-hand edge of these images, and the eastern portion of the Large Aral is below image center. Of the two major rivers that once fed the Aral Sea, the freshwater contribution from the Amu Darya River is now negligible. The Syr Darya River now only feeds the Little Aral. Depletion of the Aral Sea has led to soil and water salination and agrochemical contamination. The retreating shoreline leaves the surface encrusted with salt and with agrochemicals brought in by the rivers. As the Sea's moderating climatic influence has diminished, temperature variations in the region have altered, resulting in colder winters and hotter, drier summers. When strong westerly winds occur, large quantities of saline dust (and agrochemical toxins) can travel several hundred kilometers. In these images, several groups of low cumulus clouds are clustered over open bodies of water and are identifiable in the stereo view by their height above the surface. A number of large white streaks extend eastward toward the Kyzylkum desert. Although their altitude cannot be ascertained from the nadir image, the stereo anaglyph shows that they are close to, or at, the surface. Several of these features originate from the eastern edge of the Large Aral, and may be associated with windblown snow and/or salt particles carried aloft. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 15741. The panels cover an area of about 370 kilometers x 300 kilometers, and use data from blocks 53 to 56 within World Reference System-2 path 160. 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 ofTechnology., As recently as the 1960's the Aral Sea of Kazakhstan and Uzbekistan was the fourth-largest inland sea in the world. Since then, its water volume has dropped by about 80% due to extensive irrigation systems developed during the Soviet era to produce cotton and other crops. What was once a single body of water has now separated into several smaller seas. Since the separation of the Little Aral from the Large Aral in 1987, the shores of what had once been an island in the middle of the Large Aral (Vozrozhdeniya Island) have expanded to form a land bridge that almost completely separates the eastern and western parts of the Large Aral. These views from the Multi-angle Imaging SpectroRadiometer (MISR) portray the Little Aral and the eastern Large Aral at the onset of winter, on December 3, 2002. A natural-color view from MISR's nadir camera is shown at top, while the bottom panel is a 3D stereo anaglyph in which red-band data from the 60-degree forward-viewing camera is combined with green and blue-band data from the nadir (vertical-viewing) camera. To facilitate stereo viewing, the images have been rotated so that north is toward the left and east is toward the top. Viewing the anaglyph in 3D requires the use of red-blue glasses, with the red filter placed over your left eye. Information on ordering glasses can be found at http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] |
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Ice Types in the Beaufort Se
…
PIA04300
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Ice Types in the Beaufort Sea, Alaska |
| Original Caption Released with Image |
Determining the amount and type of sea ice in the polar oceans is crucial to improving our knowledge and understanding of polar weather and long term climate fluctuations. These views from two satellite remote sensing instruments, the synthetic aperture radar (SAR) on board the RADARSAT satellite and the Multi-angle Imaging SpectroRadiometer (MISR), illustrate different methods that may be used to assess sea ice type. Sea ice in the Beaufort Sea off the north coast of Alaska was classified and mapped in these concurrent images acquired March 19, 2001 and mapped to the same geographic area. To identify sea ice types, the National Oceanic and Atmospheric Administration (NOAA) National Ice Center constructs ice charts using several data sources including RADARSAT SAR images such as the one shown at left. SAR classifies sea ice types primarily by how the surface and subsurface roughness influence radar backscatter. In the SAR image, white lines delineate different sea ice zones as identified by the National Ice Center. Regions of mostly multi-year ice (A) are separated from regions with large amounts of first year and younger ice (B-D), and the dashed white line at bottom marks the coastline. In general, sea ice types that exhibit increased radar backscatter appear bright in SAR and are identified as rougher, older ice types. Younger, smoother ice types appear dark to SAR. Near the top of the SAR image, however, red arrows point to bright areas in which large, crystalline "frost flowers" have formed on young, thin ice, causing this young ice type to exhibit an increased radar backscatter. Frost flowers are strongly backscattering at radar wavelengths (cm) due to both surface roughness and the high salinity of frost flowers, which causes them to be highly reflective to radar energy. Surface roughness is also registered by MISR, although the roughness observed is at a different spatial scale. Older, rougher ice areas are predominantly backward scattering to the MISR cameras, whereas younger, smoother ice types are predominantly forward scattering. The MISR map at right was generated using a statistical classification routine (called ISODATA) and analyzed using ice charts from the National Ice Center. Five classes of sea ice were found based upon the classification of MISR angular data. These are described, based on interpretation of the SAR image, by the image key. Very smooth ice areas that are predominantly forward scattering are colored red. Frost flowers are largely smooth to the MISR visible band sensor and are mapped as forward scattering. Areas mapped as blue are predominantly backward scattering, and the other three classes have statistically distinct angular signatures and fall within the middle of the forward/backward scattering continuum. Some areas that may be first year or younger ice between the multi year ice floes are not discernible to SAR, illustrating how MISR potentially can make a unique contribution to sea ice mapping. 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. This data product was generated from a portion of the imagery acquired during Terra orbit 6663. The MISR image has been cropped to include an area that is 200 kilometers wide, and utilizes data from blocks 30 to 33 within World Reference System-2 path 71. 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 ofTechnology. |
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Oil Slicks on Lake Maracaibo
…
PIA04331
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Oil Slicks on Lake Maracaibo, Venezuela |
| Original Caption Released with Image |
Several oil slicks occurred on Lake Maracaibo in northwestern Venezuela between December 2002 and January 2003, and were observed by various satellite instruments. These images from the Multi-angle Imaging SpectroRadiometer (MISR) provide new information relating to one such event near the center of Lake Maracaibo on December 26, 2002. In unpolluted areas, the water surface is "ruffled" by wind and the resulting wave facets divert reflected rays into many directions. An oil film dampens the presence of small wind-driven "capillary" waves, resulting a smoother, more mirror-like surface. Also, oil is more strongly absorbing than the surrounding water. Therefore, at most viewing angles, a surface slick will appear darker than the surrounding unpolluted areas, whereas near the specular angle (the angle at which a perfect mirror reflects light) it will appear brighter. Simultaneous observation at multiple view angles therefore enhances the reliability of oil-slick detection using optical imaging. An example of how the optical contrast of an oil film on a water surface changes as a function of viewing angle is illustrated by these false-color MISR images, comprised of near-infrared, red and blue spectral data at three different angles, using the vertical-viewing camera (left), the 26°-forward-viewing camera (center) and the 46°-forward-viewing camera (right). A swirly area in the middle of the lake appears darker than the surrounding waters at both the nadir and 46° views, but brighter than the surrounding waters at the 26° view. Of the three images, only the 26° camera observes close to specular reflection angle. Lake Maracaibo is the largest lake in South America. The lake is somewhat saline, since it is connected to the Gulf of Venezuela by a narrow strait in the north. Venezuela is the largest oil producing nation in the Western Hemisphere, and the Lake Maracaibo basin includes the largest oil fields and almost a quarter of this nation's population. 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. These data products were generated from a portion of the imagery acquired during Terra orbit 16081. The panels cover an area of 72 kilometers x 225 kilometers, and utilize data from blocks 81 to 83 within World Reference System-2 path 8. 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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Seasonal Surface Changes in
…
PIA04320
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Seasonal Surface Changes in Namibia and Central Angola |
| Original Caption Released with Image |
Brightness variations in the terrain along a portion of southwestern Africa are displayed in these views from the Multi-angle Imaging SpectroRadiometer (MISR). The panels portray an area that includes Namibia's Skeleton Coast and Etosha National Park as well as Angola's Cuando Cubango. The top panels were acquired on March 6, 2001, during the region's wet season, and the bottom panels were acquired on September 1, 2002, during the dry season. Corresponding changes in the abundance of vegetation are apparent. The images on the left are natural color (red, green, blue) images from MISR's vertical-viewing (nadir) camera. The images on the right represent one of MISR's derived surface products. The radiance (light intensity) in each pixel of the so-called "top-of-atmosphere" images on the left includes light that is reflected by the Earth's surface in addition to light that is transmitted and reflected by the atmosphere. The amount of radiation reflected by the surface into all upward directions, as opposed to any single direction, is important when studying Earth's energy budget. A quantity called the surface "directional hemispherical reflectance" (DHR), sometimes called the "black-sky albedo", captures this information, and is depicted in the images on the right. MISR's multi-angle views lead to more accurate estimates of the amount of radiation reflected into all directions than can be obtained as a result of looking at a single (e.g., vertically downward) view angle. Furthermore, to generate this surface product accurately, it is necessary to compensate for the effects of the intervening atmosphere, and MISR provides the ability to characterize and account for scattering of light by airborne particulates (aerosols). The DHR is called a hemispherical reflectance because it measures the amount of radiation reflected into all upward directions, and which therefore traverses an imaginary hemisphere situated above each surface point. The "directional" part of the name describes the illumination geometry, and indicates that in the absence of an intervening atmosphere, light from the Sun illuminates the surface from a single direction (that is, there is no diffuse skylight, hence the "black-sky" terminology). The DHR is retrieved over land surfaces in each of MISR's four wavelength bands, and the images on the right are red, green, blue spectral composites. Regions where DHR could not be derived, either due to an inability to retrieve the necessary atmospheric characteristics or due to the presence of clouds, are shown in dark gray. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbits 6466 and 14388. The panels cover an area of about 380 kilometers x 760 kilometers, and utilize data from blocks 102 to 107 within World Reference, System-2 path 181. MISR was built and is managed by NASA's Jet Propulsion Laboratory,Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center,Greenbelt, MD. JPL is a division of the California Institute of Technology. |
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Global and Seasonal Surface
…
PIA04335
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Global and Seasonal Surface Albedos from MISR |
| Original Caption Released with Image |
Global models of the Earth system need accurate measurements of how much solar energy is reflected and absorbed by surfaces because this energy drives processes such as plant photosynthesis, snow melt, and longwave reradiation. These images from the Multi-angle Imaging SpectroRadiometer (MISR) provide global, seasonal summaries of a quantity called the Directional Hemispherical Reflectance (DHR), also sometimes referred to as the "black-sky" albedo. The amount of sunlight reflected from a surface, relative to the incident amount, is called the albedo. Bright surfaces have albedo near unity, and dark surfaces have albedo near zero. The DHR refers to the amount of spectral radiation reflected into all upward directions through an imaginary hemisphere situated above each surface point. The "directional" part of the name describes how, in the absence of an intervening atmosphere, light from the Sun would illuminate the surface from a single direction (that is, there is no diffuse skylight, hence the name "black-sky" albedo). To generate this product accurately, it is necessary to compensate for the effects of the atmosphere, and MISR's multi-angle retrieval techniques are used to screen clouds and account for the light scattered by airborne particulates (aerosols). The four image panels show DHR as it was retrieved over land surfaces in MISR's red, green, blue spectral bands (left), and near-infrared, red, blue spectral bands (right), for the seasonal periods December 2001 through February 2002 (top), and June 2002 through August 2002 (bottom). A one-year movie is also provided. Since relatively little sunlight reaches the polar regions during winter, the images were cropped to include only the area which is illuminated in both hemispheres during winter and summer. Noteworthy features include seasonal vegetation and the advance and retreat of the snow line. Regions where DHR could not be derived, either due to an inability to retrieve the necessary atmospheric characteristics or due to the presence of clouds, are shown in black. Further global summaries of the DHR (and other surface and vegetation products) from MISR are now available at the NASA Langley Atmospheric Sciences Data Center [ http://eosweb.larc.nasa.gov/ ]. 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. 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. |
|
Global and Seasonal Aerosol
…
PIA04333
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Global and Seasonal Aerosol Distributions from MISR |
| Original Caption Released with Image |
, depict global aerosol amount, expressed as the aerosol optical depth (or optical thickness) in MISR's green spectral band (558 nanometers). MISR algorithms retrieve aerosol amount, along with information about particle properties, from the variation in scene brightness over nine different view angles and four wavelengths. These maps were generated from data acquired during the December 2001 through November 2002 time period, and show column-integrated aerosol optical depth averaged over half-degree by half-degree grid cell areas (about 60 kilometer rectangles at low latitudes). The maps include aerosol particles of various sizes and from multiple sources, including biomass burning, mineral dust, sea salt and regional industrial pollution. A color scale is used to represent optical depth, relatively clear sky is indicated by blue and purple pixels, whereas hazier atmosphere is indicated by red, orange, yellow or green pixels. Good continuity across the land-ocean boundary is observed between the eastern Atlantic Ocean and the Saharan desert source region. Deserts are the main sources of mineral dust, and MISR obtains aerosol optical depth at visible wavelengths over these bright areas. In the southern hemisphere, elevated aerosol amounts during the austral spring (September-October-November) are associated with the increased biomass burning that occurs in South America, Southern Africa and Australia during these months. Over northeastern Asia and Europe, aerosol amounts are higher during the boreal spring season (March-April-May). Other noteworthy features are the spatial separation of African aerosol sources into two distinct bands during the June-July-August season, a peak for Central American aerosol during the March-April-May fire season, and changes that occur over the Indian subcontinent and southeastern Asia over the course of the year. One of the most challenging steps in obtaining good aerosol retrievals is the screening of clouds. The MISR algorithm uses several techniques, including radiometric (brightness) and stereoscopic cloud-detection masks. The high aerosol amounts over homogeneous ice sheets (Antarctica and Greenland) are probably an artifact of cloud screening limitations in these areas. Introduction of additional cloud masks and other product improvements are subjects of continuing work by the MISR team. 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. 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., Global summaries of aerosol optical thickness from the Multi-angle Imaging SpectroRadiometer (MISR) instrument are now available at the NASA Langley Atmospheric Sciences Data Center [http://eosweb.larc.nasa.gov/ [ http://eosweb.larc.nasa.gov/ ]]. These four panels and a 1-year movie |
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Drought and Burn Scars in So
…
PIA04321
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Drought and Burn Scars in Southeastern Australia |
| Original Caption Released with Image |
More than 2 million acres were consumed by hundreds of fires between December 2002 and February 2003 in southeastern Australia's national parks, forests, foothills and city suburbs. These images were acquired on February 14, 2002 (left) and February 17, 2003 (right) by the Multi-angle Imaging SpectroRadiometer (MISR) instrument onboard NASA's Terra satellite. The year 2002 was one of Australia's hottest and driest on record, and the acreage burnt during the summer 2002-2003 fire season in Victoria, the Australian Capital Territory and southern New South Wales, is the largest since 1938-1939, when more than 3 million acres were scorched. The extent of the burnt area and the dry conditions as of February 2003 are indicated by these contrasting false-color views. Both image panels display data from the near-infrared, red and blue spectral bands of MISR's downward-viewing (nadir) camera, as red, green and blue, respectively. This display technique causes healthy vegetation to appear red and burnt areas to show as dark brown. The data displayed from the two dates were processed identically to preserve relative brightness variations. Vegetation changes related to the dry conditions (not related to the brown burn scars) are also indicated in the February 2003 panel, where many previously red areas exhibit instead the pale yellow-brown of the underlying soils and geology. Significant reduction in the surface area of several large and important water bodies are also apparent. The diminished extent of Lake Hume (along the left-hand edge) in the later date provides a good example. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbits 14999 and 16858. The panels cover an area of about 208 kilometers x 286 kilometers, and utilize data from blocks 118 to 121 within World Reference System-2 path 91. 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 ofTechnology. |
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Lutzow-Holm Bay and the Shir
…
PIA04319
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Lutzow-Holm Bay and the Shirase Glacier, Antarctica |
| Original Caption Released with Image |
These views from the Multi-angle Imaging SpectroRadiometer (MISR) portray the Lutzow-Holm Bay region of Queen Maud Land, East Antarctica, on September 5,2002. Although Queen Maud Land remains one of the least studied regions of Antarctica, Lutzow-Holm Bay is an exception. Syowa (pronounced 'Showa') Station is the Japanese Antarctic Research Expedition base situated on Ongul Island, just off the eastern coast of the Bay (in the top right-hand portion of these views). Scientists there have studied changes in the ice sheet and sea level for several decades. Large outlet glaciers, such as the fast-flowing Shirase Glacier in the lower right-hand corner of these images, are the primary drainage systems for the Antarctic ice sheet. These two views provide information on both the spectral and angular reflectance properties of the region and can be used to understand the geophysical environment. The top panel shows the region from MISR's downward-looking (nadir) camera and is a false-color view in which the near-infrared, green and blue spectral bands have been displayed as red, green and blue. Because of the tendency of water to absorb near-infrared wavelengths, some ice types exhibit an especially bright blue hue in this display. The lower panel is a multi-angular composite from three MISR cameras in which changes in reflection at different view angles, as well as in the near-infrared spectral region, assist with the identification of rough and smooth ice surfaces. In this display, red band data from MISR's 60-degree forward and backward-viewing cameras are displayed as red and blue, respectively, and near-infrared data from the nadir camera are displayed as green. Using this technique, surfaces that predominantly exhibit backward scattering (generally rough surfaces) appear red/orange, and surfaces that predominantly exhibit forward scattering (generally smooth surfaces) appear in blue hues. Clouds (and other surfaces that exhibit both forward and backward scattering) appear purple. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuouslyand every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 16454. The panels cover an area of about 335 kilometers x 257 kilometers, and utilize data from blocks 145 to 147 within World Reference System-2 path 151. |
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Aerosols over Houston and Ga
…
PIA04303
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Aerosols over Houston and Galveston Bay |
| Original Caption Released with Image |
). These MISR views portray Houston and Galveston Bay on September 12, 2002, and display data from three of MISR's nine cameras along with a map of retrieved aerosol optical thickness. The left-hand panel is a natural-color view from MISR's vertical-viewing(nadir) camera. The center images cover the same geographic area, from the perspectives of the 70-degree forward-viewing and 70-degree backward viewing cameras. The appearance of haze is enhanced in these oblique views, and the overall area appears significantly brighter in the oblique forward view because the atmospheric particles scatter more sunlight into the forward direction. Due to geometric parallax, clouds appear to move relative to the ground as the view angle changes. At right is a map of aerosol optical depth, a measure of the amount of aerosol present in the atmosphere and one of several key variables used to characterize their climatic and environmental influence. The extent of haze across Galveston Bay can be identified by the presence of light blue and green pixels, and places where clouds or other factors precluded a retrieval are shown in dark grey. MISR uses the changes in the atmosphere's ability to transmit light and the variation in scene brightness at different viewing angles to retrieve aerosol optical depth, and to deduce some information about particle properties, such as size, shape and composition. These data are being used as part of the Houston regional air quality study. Airborne pollution particles that contribute to the poor air quality come in part from upwind power plants and petrochemical manufacturing facilities. Over a dozen local observing stations are scattered across the area to monitor air quality. The MISR aerosol data help provide a context into which the particulate pollution sources, the monitoring site observations,and locations downwind, can all be placed. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 14553. The panels cover an area of 380 kilometers x 704 kilometers, and utilize data from blocks 65to 69 within World Reference System-2 path 25. 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 ofTechnology., In the year 2000 Houston officially exceeded Los Angeles as the city with the worst air quality in the United States. Since then, major research has been underway to characterize the type, extent and sources of air pollutants in and around Houston. The Multi-angle Imaging SpectroRadiometer(MISR) is participating in work underway to study Houston's air quality (see http://www.jpl.nasa.gov/Earth/features/houston.cfm [ http://www.jpl.nasa.gov/Earth/features/houston.cfm ] |
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AIRS First Light Data: Easte
…
PIA00326
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Eastern Mediterranean, June 14, 2002 |
| Original Caption Released with Image |
Four images of the Mediterranean obtained concurrently on June 14, 2002 from the three instruments that make up the Atmospheric Infrared Sounder experiment system aboard NASA's Aqua spacecraft. The system features thousands of individual channels that observe Earth in the visible, infrared and microwave spectral regions. Each channel has a unique sensitivity to temperature, moisture, surface conditions and clouds. This visible light image from the AIRS instrument shows a band of white clouds extending from the Adriatic Sea over Greece to the Black Sea. The AIRS image (figure 1) at 900 cm-1 (11 micrometers) measures actual surface or cloud top temperatures. In it, land and ocean boundaries are well defined, with land appearing as warmer (darker red) than the ocean. The band of cold high cumulus clouds appears blue, with the darkest blue most likely a large thunderstorm. The 150 gigahertz channel from the Humidity Sounder for Brazil instrument (figure 2) is sensitive to moisture, ice particles and precipitation. The dry land temperature is comparable to the 11 micrometer temperatures, but over ocean this channel measures the temperature of moisture in the mid troposphere. The cold, blue areas off Sicily and in the Aegean Sea represent unusually dry areas over the ocean. There, clouds appear as green filaments--likely areas of precipitation. The 31.4 gigahertz channel from the Advanced Microwave Sounding Unit instrument (figure 3) is not affected by clouds. NASA's Atmospheric Infrared Sounder (AIRS) onboard NASA's Aqua spacecraft, began sending high quality data on June 12, 2002. This "first light" data is exceeding the expectations of scientists, confirming that the AIRS experiment is well on its way to meeting its goals of improving weather forecasting, establishing the connection between severe weather and climate change, determining if the global water cycle is accelerating, and detecting the effects of increased greenhouse gases. The AIRS sounding suite is a tightly integrated remote sensing system that will be used to create global three-dimensional maps of temperature, humidity and clouds in the Earth's atmosphere with unprecedented accuracy. This will lead to better weather forecasts as well as a wealth of data that will be used to study and characterize and eventually predict the global climate. The AIRS system is made up of three of the six Aqua instruments - AIRS itself, which is an infrared sounder with an unprecedented 2378 spectral channels, complemented with a 4-channel visible/near-infrared imaging module, AMSU-A, which is a 15-channel microwave temperature sounder, and HSB, which is a 4-channel microwave humidity sounder. These instruments are carefully aligned with each other and scan the atmosphere in a synchronized way, giving us simultaneous multispectral views of a highly variable target. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing, System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
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AIRS First Light Data: Easte
…
PIA00326
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Eastern Mediterranean, June 14, 2002 |
| Original Caption Released with Image |
Four images of the Mediterranean obtained concurrently on June 14, 2002 from the three instruments that make up the Atmospheric Infrared Sounder experiment system aboard NASA's Aqua spacecraft. The system features thousands of individual channels that observe Earth in the visible, infrared and microwave spectral regions. Each channel has a unique sensitivity to temperature, moisture, surface conditions and clouds. This visible light image from the AIRS instrument shows a band of white clouds extending from the Adriatic Sea over Greece to the Black Sea. The AIRS image (figure 1) at 900 cm-1 (11 micrometers) measures actual surface or cloud top temperatures. In it, land and ocean boundaries are well defined, with land appearing as warmer (darker red) than the ocean. The band of cold high cumulus clouds appears blue, with the darkest blue most likely a large thunderstorm. The 150 gigahertz channel from the Humidity Sounder for Brazil instrument (figure 2) is sensitive to moisture, ice particles and precipitation. The dry land temperature is comparable to the 11 micrometer temperatures, but over ocean this channel measures the temperature of moisture in the mid troposphere. The cold, blue areas off Sicily and in the Aegean Sea represent unusually dry areas over the ocean. There, clouds appear as green filaments--likely areas of precipitation. The 31.4 gigahertz channel from the Advanced Microwave Sounding Unit instrument (figure 3) is not affected by clouds. NASA's Atmospheric Infrared Sounder (AIRS) onboard NASA's Aqua spacecraft, began sending high quality data on June 12, 2002. This "first light" data is exceeding the expectations of scientists, confirming that the AIRS experiment is well on its way to meeting its goals of improving weather forecasting, establishing the connection between severe weather and climate change, determining if the global water cycle is accelerating, and detecting the effects of increased greenhouse gases. The AIRS sounding suite is a tightly integrated remote sensing system that will be used to create global three-dimensional maps of temperature, humidity and clouds in the Earth's atmosphere with unprecedented accuracy. This will lead to better weather forecasts as well as a wealth of data that will be used to study and characterize and eventually predict the global climate. The AIRS system is made up of three of the six Aqua instruments - AIRS itself, which is an infrared sounder with an unprecedented 2378 spectral channels, complemented with a 4-channel visible/near-infrared imaging module, AMSU-A, which is a 15-channel microwave temperature sounder, and HSB, which is a 4-channel microwave humidity sounder. These instruments are carefully aligned with each other and scan the atmosphere in a synchronized way, giving us simultaneous multispectral views of a highly variable target. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing, System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: Easte
…
PIA00326
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Eastern Mediterranean, June 14, 2002 |
| Original Caption Released with Image |
Four images of the Mediterranean obtained concurrently on June 14, 2002 from the three instruments that make up the Atmospheric Infrared Sounder experiment system aboard NASA's Aqua spacecraft. The system features thousands of individual channels that observe Earth in the visible, infrared and microwave spectral regions. Each channel has a unique sensitivity to temperature, moisture, surface conditions and clouds. This visible light image from the AIRS instrument shows a band of white clouds extending from the Adriatic Sea over Greece to the Black Sea. The AIRS image (figure 1) at 900 cm-1 (11 micrometers) measures actual surface or cloud top temperatures. In it, land and ocean boundaries are well defined, with land appearing as warmer (darker red) than the ocean. The band of cold high cumulus clouds appears blue, with the darkest blue most likely a large thunderstorm. The 150 gigahertz channel from the Humidity Sounder for Brazil instrument (figure 2) is sensitive to moisture, ice particles and precipitation. The dry land temperature is comparable to the 11 micrometer temperatures, but over ocean this channel measures the temperature of moisture in the mid troposphere. The cold, blue areas off Sicily and in the Aegean Sea represent unusually dry areas over the ocean. There, clouds appear as green filaments--likely areas of precipitation. The 31.4 gigahertz channel from the Advanced Microwave Sounding Unit instrument (figure 3) is not affected by clouds. NASA's Atmospheric Infrared Sounder (AIRS) onboard NASA's Aqua spacecraft, began sending high quality data on June 12, 2002. This "first light" data is exceeding the expectations of scientists, confirming that the AIRS experiment is well on its way to meeting its goals of improving weather forecasting, establishing the connection between severe weather and climate change, determining if the global water cycle is accelerating, and detecting the effects of increased greenhouse gases. The AIRS sounding suite is a tightly integrated remote sensing system that will be used to create global three-dimensional maps of temperature, humidity and clouds in the Earth's atmosphere with unprecedented accuracy. This will lead to better weather forecasts as well as a wealth of data that will be used to study and characterize and eventually predict the global climate. The AIRS system is made up of three of the six Aqua instruments - AIRS itself, which is an infrared sounder with an unprecedented 2378 spectral channels, complemented with a 4-channel visible/near-infrared imaging module, AMSU-A, which is a 15-channel microwave temperature sounder, and HSB, which is a 4-channel microwave humidity sounder. These instruments are carefully aligned with each other and scan the atmosphere in a synchronized way, giving us simultaneous multispectral views of a highly variable target. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing, System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: Easte
…
PIA00326
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Eastern Mediterranean, June 14, 2002 |
| Original Caption Released with Image |
Four images of the Mediterranean obtained concurrently on June 14, 2002 from the three instruments that make up the Atmospheric Infrared Sounder experiment system aboard NASA's Aqua spacecraft. The system features thousands of individual channels that observe Earth in the visible, infrared and microwave spectral regions. Each channel has a unique sensitivity to temperature, moisture, surface conditions and clouds. This visible light image from the AIRS instrument shows a band of white clouds extending from the Adriatic Sea over Greece to the Black Sea. The AIRS image (figure 1) at 900 cm-1 (11 micrometers) measures actual surface or cloud top temperatures. In it, land and ocean boundaries are well defined, with land appearing as warmer (darker red) than the ocean. The band of cold high cumulus clouds appears blue, with the darkest blue most likely a large thunderstorm. The 150 gigahertz channel from the Humidity Sounder for Brazil instrument (figure 2) is sensitive to moisture, ice particles and precipitation. The dry land temperature is comparable to the 11 micrometer temperatures, but over ocean this channel measures the temperature of moisture in the mid troposphere. The cold, blue areas off Sicily and in the Aegean Sea represent unusually dry areas over the ocean. There, clouds appear as green filaments--likely areas of precipitation. The 31.4 gigahertz channel from the Advanced Microwave Sounding Unit instrument (figure 3) is not affected by clouds. NASA's Atmospheric Infrared Sounder (AIRS) onboard NASA's Aqua spacecraft, began sending high quality data on June 12, 2002. This "first light" data is exceeding the expectations of scientists, confirming that the AIRS experiment is well on its way to meeting its goals of improving weather forecasting, establishing the connection between severe weather and climate change, determining if the global water cycle is accelerating, and detecting the effects of increased greenhouse gases. The AIRS sounding suite is a tightly integrated remote sensing system that will be used to create global three-dimensional maps of temperature, humidity and clouds in the Earth's atmosphere with unprecedented accuracy. This will lead to better weather forecasts as well as a wealth of data that will be used to study and characterize and eventually predict the global climate. The AIRS system is made up of three of the six Aqua instruments - AIRS itself, which is an infrared sounder with an unprecedented 2378 spectral channels, complemented with a 4-channel visible/near-infrared imaging module, AMSU-A, which is a 15-channel microwave temperature sounder, and HSB, which is a 4-channel microwave humidity sounder. These instruments are carefully aligned with each other and scan the atmosphere in a synchronized way, giving us simultaneous multispectral views of a highly variable target. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing, System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: North
…
PIA00345
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Northern Europe, July 20, 2002 |
| Original Caption Released with Image |
These images, taken over northern Europe on July 20, 2002, depict a few of the different views of Earth and its atmosphere that are produced by the Atmospheric Infrared Sounder experiment system operating on NASA's Aqua spacecraft. The image in Figure 1 is from an infrared channel from the AIRS instrument that measures the surface temperature in clear areas and cloud top temperatures in cloudy areas. The image reveals very warm conditions in France and a storm off the east coast of the United Kingdom. The image in Figure 2 represents a microwave channel from the Advanced Microwave Sounding Unit instrument that sees through most clouds and observes surface conditions everywhere. The image in Figure 3 is a microwave channel from the Humidity Sounder for Brazil instrument that is very sensitive to humidity and does not see the surface at all, but instead reveals the structure of moisture streams in the troposphere. The infrared and microwave data from the AIRS experiment are integrated to retrieve a single set of temperature, moisture, and cloud values. These three channels represent only a small portion of the 2,400-channel multispectral experiment, whose primary objectives are to improve the accuracy of weather forecasts and to study climate change. The AIRS experiment system also takes pictures of the Earth at four visible and near-infrared wavelengths that can be combined into a color picture. This image shows a swirling low-pressure system over England, clear skies over much of France, and frontal systems in the North Atlantic. Because AIRS is sensitive to different wavelengths than your eye, the colors shown are different from what you would see. For example, plants appear very red to AIRS. There are also subtle color differences in the clouds that relate to their altitude and thickness (compare the white clouds over England with the slightly grey-green ones near Iceland). These images are used in conjunction with other AIRS, AMSU-A, and HSB measurements to get a full 3-D view of the atmosphere. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: North
…
PIA00345
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Northern Europe, July 20, 2002 |
| Original Caption Released with Image |
These images, taken over northern Europe on July 20, 2002, depict a few of the different views of Earth and its atmosphere that are produced by the Atmospheric Infrared Sounder experiment system operating on NASA's Aqua spacecraft. The image in Figure 1 is from an infrared channel from the AIRS instrument that measures the surface temperature in clear areas and cloud top temperatures in cloudy areas. The image reveals very warm conditions in France and a storm off the east coast of the United Kingdom. The image in Figure 2 represents a microwave channel from the Advanced Microwave Sounding Unit instrument that sees through most clouds and observes surface conditions everywhere. The image in Figure 3 is a microwave channel from the Humidity Sounder for Brazil instrument that is very sensitive to humidity and does not see the surface at all, but instead reveals the structure of moisture streams in the troposphere. The infrared and microwave data from the AIRS experiment are integrated to retrieve a single set of temperature, moisture, and cloud values. These three channels represent only a small portion of the 2,400-channel multispectral experiment, whose primary objectives are to improve the accuracy of weather forecasts and to study climate change. The AIRS experiment system also takes pictures of the Earth at four visible and near-infrared wavelengths that can be combined into a color picture. This image shows a swirling low-pressure system over England, clear skies over much of France, and frontal systems in the North Atlantic. Because AIRS is sensitive to different wavelengths than your eye, the colors shown are different from what you would see. For example, plants appear very red to AIRS. There are also subtle color differences in the clouds that relate to their altitude and thickness (compare the white clouds over England with the slightly grey-green ones near Iceland). These images are used in conjunction with other AIRS, AMSU-A, and HSB measurements to get a full 3-D view of the atmosphere. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: North
…
PIA00345
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Northern Europe, July 20, 2002 |
| Original Caption Released with Image |
These images, taken over northern Europe on July 20, 2002, depict a few of the different views of Earth and its atmosphere that are produced by the Atmospheric Infrared Sounder experiment system operating on NASA's Aqua spacecraft. The image in Figure 1 is from an infrared channel from the AIRS instrument that measures the surface temperature in clear areas and cloud top temperatures in cloudy areas. The image reveals very warm conditions in France and a storm off the east coast of the United Kingdom. The image in Figure 2 represents a microwave channel from the Advanced Microwave Sounding Unit instrument that sees through most clouds and observes surface conditions everywhere. The image in Figure 3 is a microwave channel from the Humidity Sounder for Brazil instrument that is very sensitive to humidity and does not see the surface at all, but instead reveals the structure of moisture streams in the troposphere. The infrared and microwave data from the AIRS experiment are integrated to retrieve a single set of temperature, moisture, and cloud values. These three channels represent only a small portion of the 2,400-channel multispectral experiment, whose primary objectives are to improve the accuracy of weather forecasts and to study climate change. The AIRS experiment system also takes pictures of the Earth at four visible and near-infrared wavelengths that can be combined into a color picture. This image shows a swirling low-pressure system over England, clear skies over much of France, and frontal systems in the North Atlantic. Because AIRS is sensitive to different wavelengths than your eye, the colors shown are different from what you would see. For example, plants appear very red to AIRS. There are also subtle color differences in the clouds that relate to their altitude and thickness (compare the white clouds over England with the slightly grey-green ones near Iceland). These images are used in conjunction with other AIRS, AMSU-A, and HSB measurements to get a full 3-D view of the atmosphere. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: North
…
PIA00345
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Northern Europe, July 20, 2002 |
| Original Caption Released with Image |
These images, taken over northern Europe on July 20, 2002, depict a few of the different views of Earth and its atmosphere that are produced by the Atmospheric Infrared Sounder experiment system operating on NASA's Aqua spacecraft. The image in Figure 1 is from an infrared channel from the AIRS instrument that measures the surface temperature in clear areas and cloud top temperatures in cloudy areas. The image reveals very warm conditions in France and a storm off the east coast of the United Kingdom. The image in Figure 2 represents a microwave channel from the Advanced Microwave Sounding Unit instrument that sees through most clouds and observes surface conditions everywhere. The image in Figure 3 is a microwave channel from the Humidity Sounder for Brazil instrument that is very sensitive to humidity and does not see the surface at all, but instead reveals the structure of moisture streams in the troposphere. The infrared and microwave data from the AIRS experiment are integrated to retrieve a single set of temperature, moisture, and cloud values. These three channels represent only a small portion of the 2,400-channel multispectral experiment, whose primary objectives are to improve the accuracy of weather forecasts and to study climate change. The AIRS experiment system also takes pictures of the Earth at four visible and near-infrared wavelengths that can be combined into a color picture. This image shows a swirling low-pressure system over England, clear skies over much of France, and frontal systems in the North Atlantic. Because AIRS is sensitive to different wavelengths than your eye, the colors shown are different from what you would see. For example, plants appear very red to AIRS. There are also subtle color differences in the clouds that relate to their altitude and thickness (compare the white clouds over England with the slightly grey-green ones near Iceland). These images are used in conjunction with other AIRS, AMSU-A, and HSB measurements to get a full 3-D view of the atmosphere. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: Typho
…
PIA00341
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Typhoon Ramasun, July 3, 2002 |
| Original Caption Released with Image |
Four images of Tropical Cyclone Ramasun were obtained July 3, 2002 by the Atmospheric Infrared Sounder experiment system onboard NASA's Aqua spacecraft. The AIRS experiment, with its wide spectral coverage in four diverse bands, provides the ability to obtain complete 3-D observations of severe weather, from the surface, through clouds to the top of the atmosphere with unprecedented accuracy. This accuracy is the key to understanding weather patterns and improving weather predictions. Viewed separately, none of these images can provide accurate 3-D descriptions of the state of the atmosphere because of interference from clouds. However, the ability to make simultaneous observations at a wide range of wavelengths allows the AIRS experiment to "see" through clouds. This visible light picture from the AIRS instrument provides important information about the location of the cyclone, cloud structure and distribution. The AIRS instrument image at 900 cm-1 (Figure 1) is from a 10 micron transparent "window channel" that is little affected by water vapor but still cannot see through clouds. In clear areas (like the eye of the cyclone and over northwest Australia) it measures a surface temperature of about 300K (color encoded red). In cloudy areas it measures the cloud top temperature, about 200K for the cyclone, which translates to a cloud top height of about 50,000 feet. On the other hand, most clouds are relatively transparent in microwave, and the Advanced Microwave Sounding Instrument channel image (Figure 2) can see through all but the densest clouds. For example, Taiwan, which is covered by clouds, is clearly visible. The Humidity Sounder for Brazil instrument channel (Figure 3), also in the microwave, is more sensitive to both clouds and humidity. Only in clear, dry regions, such as the eye of the cyclone or the area north of Australia, does it see the surface. It is also severely affected by suspended ice particles formed by strong convection, which causes scattering and appears to be extremely cold. These blue areas indicate intense precipitation. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: Typho
…
PIA00341
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Typhoon Ramasun, July 3, 2002 |
| Original Caption Released with Image |
Four images of Tropical Cyclone Ramasun were obtained July 3, 2002 by the Atmospheric Infrared Sounder experiment system onboard NASA's Aqua spacecraft. The AIRS experiment, with its wide spectral coverage in four diverse bands, provides the ability to obtain complete 3-D observations of severe weather, from the surface, through clouds to the top of the atmosphere with unprecedented accuracy. This accuracy is the key to understanding weather patterns and improving weather predictions. Viewed separately, none of these images can provide accurate 3-D descriptions of the state of the atmosphere because of interference from clouds. However, the ability to make simultaneous observations at a wide range of wavelengths allows the AIRS experiment to "see" through clouds. This visible light picture from the AIRS instrument provides important information about the location of the cyclone, cloud structure and distribution. The AIRS instrument image at 900 cm-1 (Figure 1) is from a 10 micron transparent "window channel" that is little affected by water vapor but still cannot see through clouds. In clear areas (like the eye of the cyclone and over northwest Australia) it measures a surface temperature of about 300K (color encoded red). In cloudy areas it measures the cloud top temperature, about 200K for the cyclone, which translates to a cloud top height of about 50,000 feet. On the other hand, most clouds are relatively transparent in microwave, and the Advanced Microwave Sounding Instrument channel image (Figure 2) can see through all but the densest clouds. For example, Taiwan, which is covered by clouds, is clearly visible. The Humidity Sounder for Brazil instrument channel (Figure 3), also in the microwave, is more sensitive to both clouds and humidity. Only in clear, dry regions, such as the eye of the cyclone or the area north of Australia, does it see the surface. It is also severely affected by suspended ice particles formed by strong convection, which causes scattering and appears to be extremely cold. These blue areas indicate intense precipitation. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: Typho
…
PIA00341
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Typhoon Ramasun, July 3, 2002 |
| Original Caption Released with Image |
Four images of Tropical Cyclone Ramasun were obtained July 3, 2002 by the Atmospheric Infrared Sounder experiment system onboard NASA's Aqua spacecraft. The AIRS experiment, with its wide spectral coverage in four diverse bands, provides the ability to obtain complete 3-D observations of severe weather, from the surface, through clouds to the top of the atmosphere with unprecedented accuracy. This accuracy is the key to understanding weather patterns and improving weather predictions. Viewed separately, none of these images can provide accurate 3-D descriptions of the state of the atmosphere because of interference from clouds. However, the ability to make simultaneous observations at a wide range of wavelengths allows the AIRS experiment to "see" through clouds. This visible light picture from the AIRS instrument provides important information about the location of the cyclone, cloud structure and distribution. The AIRS instrument image at 900 cm-1 (Figure 1) is from a 10 micron transparent "window channel" that is little affected by water vapor but still cannot see through clouds. In clear areas (like the eye of the cyclone and over northwest Australia) it measures a surface temperature of about 300K (color encoded red). In cloudy areas it measures the cloud top temperature, about 200K for the cyclone, which translates to a cloud top height of about 50,000 feet. On the other hand, most clouds are relatively transparent in microwave, and the Advanced Microwave Sounding Instrument channel image (Figure 2) can see through all but the densest clouds. For example, Taiwan, which is covered by clouds, is clearly visible. The Humidity Sounder for Brazil instrument channel (Figure 3), also in the microwave, is more sensitive to both clouds and humidity. Only in clear, dry regions, such as the eye of the cyclone or the area north of Australia, does it see the surface. It is also severely affected by suspended ice particles formed by strong convection, which causes scattering and appears to be extremely cold. These blue areas indicate intense precipitation. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
AIRS First Light Data: Typho
…
PIA00341
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
AIRS First Light Data: Typhoon Ramasun, July 3, 2002 |
| Original Caption Released with Image |
Four images of Tropical Cyclone Ramasun were obtained July 3, 2002 by the Atmospheric Infrared Sounder experiment system onboard NASA's Aqua spacecraft. The AIRS experiment, with its wide spectral coverage in four diverse bands, provides the ability to obtain complete 3-D observations of severe weather, from the surface, through clouds to the top of the atmosphere with unprecedented accuracy. This accuracy is the key to understanding weather patterns and improving weather predictions. Viewed separately, none of these images can provide accurate 3-D descriptions of the state of the atmosphere because of interference from clouds. However, the ability to make simultaneous observations at a wide range of wavelengths allows the AIRS experiment to "see" through clouds. This visible light picture from the AIRS instrument provides important information about the location of the cyclone, cloud structure and distribution. The AIRS instrument image at 900 cm-1 (Figure 1) is from a 10 micron transparent "window channel" that is little affected by water vapor but still cannot see through clouds. In clear areas (like the eye of the cyclone and over northwest Australia) it measures a surface temperature of about 300K (color encoded red). In cloudy areas it measures the cloud top temperature, about 200K for the cyclone, which translates to a cloud top height of about 50,000 feet. On the other hand, most clouds are relatively transparent in microwave, and the Advanced Microwave Sounding Instrument channel image (Figure 2) can see through all but the densest clouds. For example, Taiwan, which is covered by clouds, is clearly visible. The Humidity Sounder for Brazil instrument channel (Figure 3), also in the microwave, is more sensitive to both clouds and humidity. Only in clear, dry regions, such as the eye of the cyclone or the area north of Australia, does it see the surface. It is also severely affected by suspended ice particles formed by strong convection, which causes scattering and appears to be extremely cold. These blue areas indicate intense precipitation. The Atmospheric Infrared Sounder is an instrument onboard NASA's Aqua satellite under the space agency's Earth Observing System. The sounding system is making highly accurate measurements of air temperature, humidity, clouds and surface temperature. Data will be used to better understand weather and climate. It will also be used by the National Weather Service and the National Oceanic and Atmospheric Administration to improve the accuracy of their weather and climate models. The instrument was designed and built by Lockheed Infrared Imaging Systems (recently acquired by British Aerospace) under contract with JPL. The Aqua satellite mission is managed by NASA's Goddard Space Flight Center. |
|
Supertyphoon Pongsona
PIA00367
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Supertyphoon Pongsona |
| Original Caption Released with Image |
Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena, Three Different Views of Supertyphoon Pongsona, December 2002 Packing gusts of 296.1 kilometers per hour (184 miles per hour) and sustained winds of 241.4 kilometers per hour (150 miles per hour), Supertyphoon Pongsona struck the U.S. Island of Guam on Sunday, December 8. The storm cut off electricity over the entire island along with telephone and water service, and President George W. Bush declared the U.S. territory a federal disaster area. Pongsona is the third typhoon to hit Guam since June, and the second cyclone of supertyphoon status to hit in five years. These images were made from data acquired by the Atmospheric Infrared Sounding System (AIRS) instrument suite aboard NASA's Aqua spacecraft just as the eye of the storm was about to pass over Guam. This image was made using visible/near-infrared data using the AIRS instrument. Its 2-kilometer (1.24-mile) resolution shows fine details of the cloud structure and can be used to help interpret the other images. It confirms that the eye was not cloud free at the time the data was acquired, and pinpoints towering thunderheads rising up in several areas of the spiral arms (see figure 1 for close-up). The image in figure 2 shows how the typhoon looks through an AIRS infrared "window" channel, which measures the temperature of the nearest impenetrable surface. Where the sky is clear, this window channel shows the surface of the Earth, otherwise it will show cloud tops. High cold clouds appear blue, while lower warmer clouds are green through orange. The Earth's surface, where it can be seen between the clouds, is warmest and appears red. Although the storm has a clearly defined eye, it is not cloud free and therefore shows up as yellow in this infrared image. The image in figure 3 shows how the typhoon looks through a microwave channel of the Humidity Sounder for Brazil (HSB), a component of the AIRS instrument suite. This channel, which is sensitive to humidity, clouds and rain, sees through much of the clouds and reveals some of the inner structure of the storm. Here the eye is more clearly defined than in the infrared image and appears to be very large - perhaps 80.5 kilometers (50 miles) across. Rain areas appear as blue patches, and a very intense rain cell can be seen right over Guam itself. This cell is in the leading eye wall and is probably associated with the highest wind speeds. It is likely that much of the damage in Guam was caused by this particular part of the storm. In the near future, when estimates of the three-dimensional distribution of the temperature, humidity and clouds in the atmosphere are also routinely derived from the AIRS sounding system, it will be possible to get a unique view of the interior of destructive storms like Pongsona. The new knowledge gained will eventually make for more accurate forecasts of such events. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at |
|
Supertyphoon Pongsona
PIA00367
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Supertyphoon Pongsona |
| Original Caption Released with Image |
Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena, Three Different Views of Supertyphoon Pongsona, December 2002 Packing gusts of 296.1 kilometers per hour (184 miles per hour) and sustained winds of 241.4 kilometers per hour (150 miles per hour), Supertyphoon Pongsona struck the U.S. Island of Guam on Sunday, December 8. The storm cut off electricity over the entire island along with telephone and water service, and President George W. Bush declared the U.S. territory a federal disaster area. Pongsona is the third typhoon to hit Guam since June, and the second cyclone of supertyphoon status to hit in five years. These images were made from data acquired by the Atmospheric Infrared Sounding System (AIRS) instrument suite aboard NASA's Aqua spacecraft just as the eye of the storm was about to pass over Guam. This image was made using visible/near-infrared data using the AIRS instrument. Its 2-kilometer (1.24-mile) resolution shows fine details of the cloud structure and can be used to help interpret the other images. It confirms that the eye was not cloud free at the time the data was acquired, and pinpoints towering thunderheads rising up in several areas of the spiral arms (see figure 1 for close-up). The image in figure 2 shows how the typhoon looks through an AIRS infrared "window" channel, which measures the temperature of the nearest impenetrable surface. Where the sky is clear, this window channel shows the surface of the Earth, otherwise it will show cloud tops. High cold clouds appear blue, while lower warmer clouds are green through orange. The Earth's surface, where it can be seen between the clouds, is warmest and appears red. Although the storm has a clearly defined eye, it is not cloud free and therefore shows up as yellow in this infrared image. The image in figure 3 shows how the typhoon looks through a microwave channel of the Humidity Sounder for Brazil (HSB), a component of the AIRS instrument suite. This channel, which is sensitive to humidity, clouds and rain, sees through much of the clouds and reveals some of the inner structure of the storm. Here the eye is more clearly defined than in the infrared image and appears to be very large - perhaps 80.5 kilometers (50 miles) across. Rain areas appear as blue patches, and a very intense rain cell can be seen right over Guam itself. This cell is in the leading eye wall and is probably associated with the highest wind speeds. It is likely that much of the damage in Guam was caused by this particular part of the storm. In the near future, when estimates of the three-dimensional distribution of the temperature, humidity and clouds in the atmosphere are also routinely derived from the AIRS sounding system, it will be possible to get a unique view of the interior of destructive storms like Pongsona. The new knowledge gained will eventually make for more accurate forecasts of such events. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at |
|
Supertyphoon Pongsona
PIA00367
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Supertyphoon Pongsona |
| Original Caption Released with Image |
Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena, Three Different Views of Supertyphoon Pongsona, December 2002 Packing gusts of 296.1 kilometers per hour (184 miles per hour) and sustained winds of 241.4 kilometers per hour (150 miles per hour), Supertyphoon Pongsona struck the U.S. Island of Guam on Sunday, December 8. The storm cut off electricity over the entire island along with telephone and water service, and President George W. Bush declared the U.S. territory a federal disaster area. Pongsona is the third typhoon to hit Guam since June, and the second cyclone of supertyphoon status to hit in five years. These images were made from data acquired by the Atmospheric Infrared Sounding System (AIRS) instrument suite aboard NASA's Aqua spacecraft just as the eye of the storm was about to pass over Guam. This image was made using visible/near-infrared data using the AIRS instrument. Its 2-kilometer (1.24-mile) resolution shows fine details of the cloud structure and can be used to help interpret the other images. It confirms that the eye was not cloud free at the time the data was acquired, and pinpoints towering thunderheads rising up in several areas of the spiral arms (see figure 1 for close-up). The image in figure 2 shows how the typhoon looks through an AIRS infrared "window" channel, which measures the temperature of the nearest impenetrable surface. Where the sky is clear, this window channel shows the surface of the Earth, otherwise it will show cloud tops. High cold clouds appear blue, while lower warmer clouds are green through orange. The Earth's surface, where it can be seen between the clouds, is warmest and appears red. Although the storm has a clearly defined eye, it is not cloud free and therefore shows up as yellow in this infrared image. The image in figure 3 shows how the typhoon looks through a microwave channel of the Humidity Sounder for Brazil (HSB), a component of the AIRS instrument suite. This channel, which is sensitive to humidity, clouds and rain, sees through much of the clouds and reveals some of the inner structure of the storm. Here the eye is more clearly defined than in the infrared image and appears to be very large - perhaps 80.5 kilometers (50 miles) across. Rain areas appear as blue patches, and a very intense rain cell can be seen right over Guam itself. This cell is in the leading eye wall and is probably associated with the highest wind speeds. It is likely that much of the damage in Guam was caused by this particular part of the storm. In the near future, when estimates of the three-dimensional distribution of the temperature, humidity and clouds in the atmosphere are also routinely derived from the AIRS sounding system, it will be possible to get a unique view of the interior of destructive storms like Pongsona. The new knowledge gained will eventually make for more accurate forecasts of such events. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at |
|
Supertyphoon Pongsona
PIA00367
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Supertyphoon Pongsona |
| Original Caption Released with Image |
Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena, Three Different Views of Supertyphoon Pongsona, December 2002 Packing gusts of 296.1 kilometers per hour (184 miles per hour) and sustained winds of 241.4 kilometers per hour (150 miles per hour), Supertyphoon Pongsona struck the U.S. Island of Guam on Sunday, December 8. The storm cut off electricity over the entire island along with telephone and water service, and President George W. Bush declared the U.S. territory a federal disaster area. Pongsona is the third typhoon to hit Guam since June, and the second cyclone of supertyphoon status to hit in five years. These images were made from data acquired by the Atmospheric Infrared Sounding System (AIRS) instrument suite aboard NASA's Aqua spacecraft just as the eye of the storm was about to pass over Guam. This image was made using visible/near-infrared data using the AIRS instrument. Its 2-kilometer (1.24-mile) resolution shows fine details of the cloud structure and can be used to help interpret the other images. It confirms that the eye was not cloud free at the time the data was acquired, and pinpoints towering thunderheads rising up in several areas of the spiral arms (see figure 1 for close-up). The image in figure 2 shows how the typhoon looks through an AIRS infrared "window" channel, which measures the temperature of the nearest impenetrable surface. Where the sky is clear, this window channel shows the surface of the Earth, otherwise it will show cloud tops. High cold clouds appear blue, while lower warmer clouds are green through orange. The Earth's surface, where it can be seen between the clouds, is warmest and appears red. Although the storm has a clearly defined eye, it is not cloud free and therefore shows up as yellow in this infrared image. The image in figure 3 shows how the typhoon looks through a microwave channel of the Humidity Sounder for Brazil (HSB), a component of the AIRS instrument suite. This channel, which is sensitive to humidity, clouds and rain, sees through much of the clouds and reveals some of the inner structure of the storm. Here the eye is more clearly defined than in the infrared image and appears to be very large - perhaps 80.5 kilometers (50 miles) across. Rain areas appear as blue patches, and a very intense rain cell can be seen right over Guam itself. This cell is in the leading eye wall and is probably associated with the highest wind speeds. It is likely that much of the damage in Guam was caused by this particular part of the storm. In the near future, when estimates of the three-dimensional distribution of the temperature, humidity and clouds in the atmosphere are also routinely derived from the AIRS sounding system, it will be possible to get a unique view of the interior of destructive storms like Pongsona. The new knowledge gained will eventually make for more accurate forecasts of such events. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at |
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Mt. Etna Eruption
PIA00355
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Mt. Etna Eruption |
| Original Caption Released with Image |
October 2002 Mt. Etna, a volcano on the island of Sicily, erupted on October 26, 2002. Preliminary analysis of data taken by the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite on October 28 shows the instrument can provide an excellent means to study the evolution and structure of the sulfur dioxide (SO2) plume emitted from volcanoes. These data also demonstrate that AIRS can be used to obtain the total mass of SO2 injected into the atmosphere during a volcanic event, information that may help us to better understand these dangerous natural occurrences in the future. This image was made from a sensor on the AIRS instrument that is sensitive to the visible and near-infrared portions of the spectrum. The visible/near infrared data show the smoke plume from Mt. Etna. The view is of Europe and the central Mediterranean with Italy in the center. Since the visible/near infrared sensor on AIRS is sensitive to wavelengths that are different than the human eye, vegetated regions appear red (compare the red color of Europe with the tan desert of North Africa in the lower left). Figure 1 is a closer view of Sicily and shows a long, brownish smoke plume extending across the Mediterranean to Africa. This is consistent with the enhanced feature in the difference image in Figure 2 and helps validate the information inferred from that image. Figure 2 clearly shows the SO2 plume. This image was created by comparing data taken at two different frequencies, or channels, and creating one image that highlights the differences between these two channels. Both channels are sensitive to water vapor, but one of the channels is also sensitive to SO2. By subtracting out the common water vapor signal in both channels, the SO2 feature remains and shows up as an enhancement in the difference image. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena |
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Mt. Etna Eruption
PIA00355
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Mt. Etna Eruption |
| Original Caption Released with Image |
October 2002 Mt. Etna, a volcano on the island of Sicily, erupted on October 26, 2002. Preliminary analysis of data taken by the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite on October 28 shows the instrument can provide an excellent means to study the evolution and structure of the sulfur dioxide (SO2) plume emitted from volcanoes. These data also demonstrate that AIRS can be used to obtain the total mass of SO2 injected into the atmosphere during a volcanic event, information that may help us to better understand these dangerous natural occurrences in the future. This image was made from a sensor on the AIRS instrument that is sensitive to the visible and near-infrared portions of the spectrum. The visible/near infrared data show the smoke plume from Mt. Etna. The view is of Europe and the central Mediterranean with Italy in the center. Since the visible/near infrared sensor on AIRS is sensitive to wavelengths that are different than the human eye, vegetated regions appear red (compare the red color of Europe with the tan desert of North Africa in the lower left). Figure 1 is a closer view of Sicily and shows a long, brownish smoke plume extending across the Mediterranean to Africa. This is consistent with the enhanced feature in the difference image in Figure 2 and helps validate the information inferred from that image. Figure 2 clearly shows the SO2 plume. This image was created by comparing data taken at two different frequencies, or channels, and creating one image that highlights the differences between these two channels. Both channels are sensitive to water vapor, but one of the channels is also sensitive to SO2. By subtracting out the common water vapor signal in both channels, the SO2 feature remains and shows up as an enhancement in the difference image. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena |
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Mt. Etna Eruption
PIA00355
Sol (our sun)
Atmospheric Infrared Sounder
…
| Title |
Mt. Etna Eruption |
| Original Caption Released with Image |
October 2002 Mt. Etna, a volcano on the island of Sicily, erupted on October 26, 2002. Preliminary analysis of data taken by the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite on October 28 shows the instrument can provide an excellent means to study the evolution and structure of the sulfur dioxide (SO2) plume emitted from volcanoes. These data also demonstrate that AIRS can be used to obtain the total mass of SO2 injected into the atmosphere during a volcanic event, information that may help us to better understand these dangerous natural occurrences in the future. This image was made from a sensor on the AIRS instrument that is sensitive to the visible and near-infrared portions of the spectrum. The visible/near infrared data show the smoke plume from Mt. Etna. The view is of Europe and the central Mediterranean with Italy in the center. Since the visible/near infrared sensor on AIRS is sensitive to wavelengths that are different than the human eye, vegetated regions appear red (compare the red color of Europe with the tan desert of North Africa in the lower left). Figure 1 is a closer view of Sicily and shows a long, brownish smoke plume extending across the Mediterranean to Africa. This is consistent with the enhanced feature in the difference image in Figure 2 and helps validate the information inferred from that image. Figure 2 clearly shows the SO2 plume. This image was created by comparing data taken at two different frequencies, or channels, and creating one image that highlights the differences between these two channels. Both channels are sensitive to water vapor, but one of the channels is also sensitive to SO2. By subtracting out the common water vapor signal in both channels, the SO2 feature remains and shows up as an enhancement in the difference image. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena |
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Bay of Fundy
PIA01912
Sol (our sun)
ASTER
| Title |
Bay of Fundy |
| Original Caption Released with Image |
The highest tides on Earth occur in the Minas Basin, the eastern extremity of the Bay of Fundy, Nova Scotia, Canada, where the tide range can reach 16 meters when the various factors affecting the tides are in phase. The primary cause of the immense tides of Fundy is a resonance of the Bay of Fundy-Gulf of Maine system. The system is effectively bounded at this outer end by the edge of the continental shelf with its approximately 40:1 increase in depth. The system has a natural period of approximately 13 hours, which is close to the 12h25m period of the dominant lunar tide of the Atlantic Ocean. Like a father pushing his daughter on a swing, the gentle Atlantic tidal pulse pushes the waters of the Bay of Fundy-Gulf of Maine basin at nearly the optimum frequency to cause a large to-and-fro oscillation. The greatest slosh occurs at the head (northeast end) of the system. The high tide image (top) was acquired April 20, 2001, and the low tide image (bottom) was acquired September 30, 2002. The images cover an area of 16.5 by 21 km, and are centered near 64 degrees west longitude and 45.5 degrees north latitude. 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 monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 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. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate. Size: 16.5 by 21 kilometers (10.2 by 13 miles) Location: 45.4 degrees North latitude, 64 degrees West longitude Image Data: ASTER bands 3, 2, and 1 Original Data Resolution: 15 meters (49.2 feet) Dates Acquired: September 30, 2002 |
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Smoke from Fires in Southern
…
PIA03706
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Smoke from Fires in Southern Mexico |
| Original Caption Released with Image |
On May 2, 2002, numerous fires in southern Mexico sent smoke drifting northward over the Gulf of Mexico. These views from the Multi-angle Imaging SpectroRadiometer illustrate the smoke extent over parts of the Gulf and the southern Mexican states of Tabasco, Campeche and Chiapas. At the same time, dozens of other fires were also burning in the Yucatan Peninsula and across Central America. A similar situation occurred in May and June of 1998, when Central American fires resulted in air quality warnings for several U.S. States. The image on the left is a natural color view acquired by MISR's vertical-viewing (nadir) camera. Smoke is visible, but sunglint in some ocean areas makes detection difficult. The middle image, on the other hand, is a natural color view acquired by MISR's 70-degree backward-viewing camera, its oblique view angle simultaneously suppresses sunglint and enhances the smoke. A map of aerosol optical depth, a measurement of the abundance of atmospheric particulates, is provided on the right. This quantity is retrieved using an automated computer algorithm that takes advantage of MISR's multi-angle capability. Areas where no retrieval occurred are shown in black. The images each represent an area of about 380 kilometers x 1550 kilometers and were captured during Terra orbit 12616. 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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Spectacular Mountain Views o
…
PIA03711
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Spectacular Mountain Views of Northwest Colorado |
| Original Caption Released with Image |
The mountains and desert plateaus of northwest Colorado are contrasted here in two views from the Multi-angle Imaging SpectroRadiometer (MISR). On the left, a natural-color view acquired by MISR's vertical-viewing (nadir) camera illustrates these features at a pixel resolution of 275 meters. A striking example of the capability of multiple view angles to illustrate topography is provided by the 3D stereo anaglyph view on the right, which was created by combining data from MISR's 46-degree forward-viewing and nadir cameras. To facilitate stereo viewing, both images have been oriented with north toward the left. Viewing the stereo image in 3D requires the use of red/blue glasses (info found here) [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ]) with the red filter placed over your left eye. Undoubtedly the dominant feature of central Colorado are the Rocky Mountains. Running roughly north-south within the eastern portion of the image (across the top in this orientation) mountain ranges pictured here include the Medicine Bow, Front, Gore and the Sawatch. The Colorado River originates in the Rocky Mountains National Park near Lake Granby -- a dark blue lake in the upper edge of the image toward the right of center. Other water bodies shown include Antero Reservoir in the top right corner. The highest peak in the U.S. Rocky Mountains, Mount Elbert, is situated west of Antero about halfway between the Turquoise and Twin Lakes. The Colorado River traverses the length of the image, running roughly east and south to the lower right-hand corner, where it meets the Gunnison River at the city of Grand Junction. The striking "L" shaped feature in the lower image center is a sandstone monocline known as the Grand Hogback. The Yampa River runs from its headwaters in the highlands about 65 kilometers north of Steamboat Springs to Dinosaur National Monument in the lower left corner. Steamboat Springs is the site of the Third International Workshop on Multiangular Measurements and Models http://cires.colorado.edu/iwmmm-3/ [ http://cires.colorado.edu/iwmmm-3/ ] through June 12, 2002. The images were acquired on September 12, 2000 (during Terra orbit 3923) and cover an area of about 226 kilometers by 257 kilometers. They utilize data from blocks 58 to 59 within World Reference System-2 path 35. 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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Dust Obscures Liaoning Provi
…
PIA03705
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Dust Obscures Liaoning Province, China |
| Original Caption Released with Image |
This pair of Multi-angle Imaging SpectroRadiometer images, acquired 16 days apart, covers the Liaoning region of China and parts of northern and western Korea. They contrast a relatively clear day (March 23, 2002) with one in which the skies were extremely dusty (April 8, 2002). In the later view(right-hand image), the dust obscures most of the surface, although the Liaodong peninsula extending between the Bo Hai Sea and Korea Bay is faintly visible at the lower left. Wave features are apparent within the dust layer. Storms such as this transport mineral dust from the deserts of China and Mongolia over great distances, and pollution from agriculture, industry and power generation is also carried aloft. Thick clouds of dust block substantial amounts of incoming sunlight, which in turn can influence marine phytoplankton production and have a cooling effect on regional climates. Small dust particles can remain airborne for many thousands of kilometers, and the National Oceanic and Atmospheric Administration detected dust from the 2002 Asian storms as far away as Colorado(http://www.noaanews.noaa.gov/stories/s885.htm [ http://www.noaanews.noaa.gov/stories/s885.htm ]). These natural color views were acquired by MISR's nadir camera, during Terra orbits 12025 and 12258. Each image represents an area of about 280 kilometers x 342 kilometers. |
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Unique Views of a Shattered
…
PIA03702
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Unique Views of a Shattered Ice Shelf |
| Original Caption Released with Image |
Both single and multi-angle views of the breakup of the northern section of the Larsen B ice shelf are shown in this image pair from the Multi-angle Imaging SpectroRadiometer. The Larsen B ice shelf collapsed and broke away from the Antarctic Peninsula during February and March, 2002 -- a progression observed by Terra's Moderate-resolution Imaging SpectroRadiometer (MODIS) and analyzed at the University of Colorado's National Snow and Ice Data Center. The collapse is thought to have been accelerated by warm summer temperatures which caused meltwater to fill crevasses along the landward side of the Larsen shelf, leading to intensified pressures within the sheet structure. In the left-hand view, spectral variations across the scene are highlighted by using near-infrared, red and blue data from MISR's nadir (vertical-viewing) camera. Here, the ice within the disintegrating ice shelf appears vibrant blue. Water has an intrinsic blue color due to the selective absorption of longer wavelengths such as red and infrared, and the translucent properties of ice within the collapsing shelf enables this absorption to be observed. The use of the near-infrared band within this false-color composite accentuates the effect. Light brownish streaks across the splintering sheet can also be discerned, and probably indicate regions where rocks and morainal debris were exposed from the interior of the shelf. On the right, data from three different view angles and only one color channel were combined to create a multi-angle composite. This image displays red-band data from MISR's 46-degree forward, nadir, and 46-degree backward-viewing cameras as red, green and blue, respectively. Here, the disintegrating ice shelf and the rough crevasses of glaciers appear orange. In contrast to the spectral composite, which provides information on the chemical composition of water ice, the colors in the right-hand image represent properties related to its physical nature. Because vertical protrusions or depressions within textured surfaces appear brighter on their illuminated faces, the orange color in the multi-angle composite suggests a macroscopically rough ice surface. Low clouds in the multi-angle view appear purple due to their ability to both forward scatter and backward scatter sunlight. Higher clouds and mountainous terrain are subject to geometric parallax which splits the imagery into spatially separated components, and their unusual appearance is an artifact of this effect. These views were acquired on March 7, 2002, during Terra orbit 11798. Each image represents an area of approximately 149 kilometers x 186 kilometers. 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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Tornado Cuts Through La Plat
…
PIA03707
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Tornado Cuts Through La Plata, Maryland |
| Original Caption Released with Image |
A category F4 tornado tore through La Plata, Maryland on April 28, 2002, killing 5 and injuring more than 100 people. Vegetation and surface structures were pulled up or damaged along a swath measuring 39 kilometers long. This pair of images from the Multi-angle Imaging SpectroRadiometer (MISR) illustrates the strip of flattened vegetation left by the tornado. The top image was acquired by MISR's nadir (vertical-viewing) camera on May 1,2002. The tornado swath is barely visible in this natural-color view, which has a spatial resolution of 275 meters. In the lower view, near infrared data from the May 1 date are combined with data from about one year earlier (April 28,2001) to highlight vegetation changes between the two dates. Here, the 2002 (post tornado) data are displayed as blue/green, and the 2001 data as red. In this temporal false color composite, areas with less vegetation on the later date appear bright red. The horizontal red line between the Potomac and Patuxent rivers in Maryland indicates the swath cut by the tornado. Washington, DC is located in the upper left-hand quadrant of the images. The images utilize data from blocks 59 to 61 within World Reference System-2 path 15.Another view [ http://asterweb.jpl.nasa.gov/gallery/gallery.htm?name=Tornado ] of the area damaged by the tornado at a spatial resolution of 15 meters per pixel is available from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/default.htm ]), also onboard the Terra satellite. 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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Southern Florida's River of
…
PIA03703
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Southern Florida's River of Grass |
| Original Caption Released with Image |
Florida's Everglades is a region of broad, slow-moving sheets of water flowing southward over low-lying areas from Lake Okeechobeeto the Gulf of Mexico. In places this remarkable "river of grass" is 80 kilometers wide. These images from the Multi-angle Imaging SpectroRadiometer show the Everglades region on January 16, 2002. Each image covers an area measuring 191 kilometers x 205 kilometers. The data were captured during Terra orbit 11072. On the left is a natural color view acquired by MISR's nadir camera. A portion of Lake Okeechobee is visible at the top, to the right of image center. South of the lake, whose name derives from the Seminole word for "big water," an extensive region of farmland known as the Everglades Agricultural Area is recognizable by its many clustered squares. Over half of the sugar produced in United States is grown here. Urban areas along the east coast and in the northern part of the image extend to the boundaries of Big Cypress Swamp, situated north of Everglades National Park. The image on the right combines red-band data from the 46-degree backward, nadir and 46-degree forward-viewing camera angles to create a red, green, blue false-color composite. One of the interesting uses of the composite image is for detecting surface water. Wet surfaces appear blue in this rendition because sun glitter produces a greater signal at the forward camera's view angle. Wetlands visible in these images include a series of shallow impoundments called Water Conservation Areas which were built to speed water flow through the Everglades in times of drought. In parts of the Everglades, these levees and extensive systems such as the Miami and Tamiami Canals have altered the natural cycles of water flow. For example, the water volume of the Shark River Slough, a natural wetland which feeds Everglades National Park, is influenced by the Tamiami Canal. The unique and intrinsic value of the Everglades is now widely recognized, and efforts to restore the natural water cycles are underway. |
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A Hard Look at Thin Clouds
PIA03719
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
A Hard Look at Thin Clouds |
| Original Caption Released with Image |
. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and views almost the entire globe every 9 days. This MISR image is a portion of the data acquired during Terra orbit 13606 and covers an area of about 232 kilometers x 267 kilometers. The image contains data from blocks 73 to 75 within World Reference System-2 path 18. 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., Despite their delicate appearance, thin, feathery clouds of ice crystals called cirrus may contribute to global warming. Some scientists believe cirrus is quite common, but it is notoriously difficult to observe -- even from satellites, which offer our only means of monitoring such clouds over the entire planet. The Multi-angle Imaging SpectroRadiometer (MISR), one of a new generation of instruments flying aboard the NASA Earth Observing System's Terra satellite, views Earth with nine cameras simultaneously, some at very steep angles through the atmosphere. Scientists on the MISR team have been hoping to learn what contributions their instrument can make to a global inventory of cirrus. They got their chance to test MISR's capabilities during July 2002, when they joined over 400 other scientists and six research aircraft at the US Naval Air Station near Key West, Florida for the Cirrus Regional Study of Tropical Anvils Layers-Florida Area Cirrus Experiment (CRYSTAL-FACE) field campaign. The campaign had many goals, one of which was making simultaneous aircraft and satellite measurements of cirrus. On July 9, the ER-2 stratospheric jet aircraft, carrying a multi-spectral camera called the MODIS Airborne Simulator (MAS), flew in the stratosphere above a 35-kilometer-wide patch of thin cirrus minutes after MISR imaged the cloud from space. At the same time, another NASA high-altitude jet, the WB-57, flew right through the 15-kilometer-high cloud with cloud particle counters and a particle imager. The left side of this montage is a natural-color view of the Caribbean Sea east of the Yucatan Peninsula as seen by MISR's most steeply forward-viewing camera. The thin line running roughly north-south was drawn on this image along the flight tracks of the stacked ER-2 and WB-57, and the red arrow points to a crescent-shaped cirrus cloud. At right is a false-color image taken 700 kilometers closer by the MAS instrument on the ER-2. Data from the MAS shortwave infrared channel that detects cirrus is shown in blue. An animation of the cloud as seen by seven of the nine MISR cameras is also shown. It progresses from the most steeply forward to the most steeply backward view, and excludes imagery from two angles which had significant sunglint. These gray-scale images use MISR's red band. The cirrus is prominent at the steeper angles and virtually disappears in the nearly vertical views. Because it is so much higher, the cirrus seems to move more than the background clouds. The animation also shows the 3-dimensional structure of many towering cumulus clouds. By analyzing these data sets, scientists will learn how effectively they can use MISR observations to map thin cirrus, and to monitor changes in its distribution from season to season and year to year. For more information about the CRYSTAL-FACE campaign, visit: http://cloud1.arc.nasa.gov/crystalface/ [ http://cloud1.arc.nasa.gov/crystalface/ ] |
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