|
|
Indonesian Tropospheric Ozon
| Title |
Indonesian Tropospheric Ozone and Aerosol Index |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2000-10-19 |
|
Indonesian Tropospheric Ozon
| Title |
Indonesian Tropospheric Ozone and Aerosol Index |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2000-10-19 |
|
Indonesian Tropospheric Ozon
| Title |
Indonesian Tropospheric Ozone and Aerosol Index |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2000-10-19 |
|
Indonesian Tropospheric Ozon
| Title |
Indonesian Tropospheric Ozone and Aerosol Index |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2000-10-19 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indian Ocean to Indonesia Zoom |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indian Ocean to Indonesia Zoom |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indonesia |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indonesia |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indonesia |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indonesia |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indonesia |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Tropospheric Ozone and Smoke
| Title |
Tropospheric Ozone and Smoke from Earth Probe TOMS: Indonesia |
| Abstract |
Researchers have discovered that smoke and smog move in different ways through the atmosphere. A series of unusual events several years ago created a blanket of pollution over the Indian Ocean. In this animation, significant smog or tropospheric ozone is represented by red and green and regions of significant smoke index are in shades of white and gray. |
| Completed |
2001-03-06 |
|
Earthquake Spawns Tsunamis
| Title |
Earthquake Spawns Tsunamis |
| Description |
The Earth?s solid surface floats on a layer of softer rock as a collection of interlocking, movable puzzle pieces called tectonic plates. At 7:58 a.m. (local time), on December 26, 2004, beneath the Indian Ocean west of Sumatra, Indonesia, pent-up energy from the compressional forces of one tectonic plate grinding under another found a weak spot in the overlying rock. The rock was thrust upward, and the Earth shook as a 9.0 magnitude earthquake sent its vibrations out into the ocean. Tsunamis spread out in all directions, the massive waves washed over islands and crashed against coastlines in Sri Lanka, Southern India, and even the east coast of Africa. Tens of thousands of people were killed, millions are homeless. The image above shows how the tectonic puzzle pieces fit together around Indonesia. The epicenter of the recent quake is marked with a red star in the image. It is located just to the east of the Sunda Trench, where the India Plate begins to get subducted beneath (forced under) the Burma Plate. The blue arrows along the plate boundary show the direction of subduction. As the India Plate slides beneath the Burma Plate, it meets pockets of resistance, which causes compressional forces to build up. Weakened overlying rock gets forced upward. Based on the location of aftershocks (red shaded circles on the image), the United States Geological Survey reports that approximately 1,200 kilometers of the plate boundary probably slipped as a result of the quake. The initial rupture was likely more than 100 kilometers wide, and probably produced an average vertical displacement along the fault plane (the slope along which the two plates meet) of 15 meters. When the bottom of the ocean is deformed by this type of ?megathrust? quake, the upward force acts like a fist rising up from underwater. Water rolls down off the sides of the ?fist,? creating massive waves that can travel as fast as an airplane. The waves can move across the ocean and barely disturb the surface, but when they reach shallow coastal water, the earthquake?s energy thrusts them tens of meters into the air. The tsunami created by this earthquake reached India and Sri Lanka in about four hours. The wave eventually reached Africa, the Pacific Ocean, Hawaii, and the west coast of North and South America. For more information about this earthquake and plate tectonics, visit the Website of the USGS. [ http://earthquake.usgs.gov/eqinthenews/2004/usslav/ ] Image courtesy United States Geological Survey [ http://www.usgs.gov/ ] |
|
Earthquake Spawns Tsunamis
| Title |
Earthquake Spawns Tsunamis |
| Description |
On December 26, 2004, a large (magnitude 9.0) earthquake occurred off the western coast of Sumatra in the Indian Ocean. The earthquake was caused by the release of stresses accumulated as the Burma tectonic plate overrides the India tectonic plate. Movement of the seafloor due to the earthquake generated a tsunami, or seismic sea wave, that affected coastal regions around the Indian Ocean. The northwestern Sumatra coastline in particular suffered extensive damage and loss of life. These astronaut photographs illustrate damage along the southwestern coast of Aceh Province in the vicinity of the city of Lho? Kruet, Indonesia. Large areas of bare and disturbed soil (brownish gray) that were previously covered with vegetation are visible along the coastline in the near-nadir (top) image. Embayments in the coastline were particularly hard hit, while adjacent headlands were less affected. The oblique (lower) astronaut photograph was acquired 45 seconds after the near-nadir photograph, and captures sunglint illuminating the Indian Ocean and standing water inland (light gray, yellow). Distortion and scale differences in the images are caused by increased obliquity of the view from the International Space Station. Arrows on the photographs indicate several points of comparison between the two images. Standing bodies of seawater may inhibit revegetation of damaged areas and act as sources of salt contamination in soil and groundwater. Astronaut photographs ISS010-E-13079 [ http://eol.jsc.nasa.gov/scripts/sseop/photo.pl?mission=ISS010&roll=E&frame=13079 ] (top) and ISS010-E-13088 [ http://eol.jsc.nasa.gov/scripts/sseop/photo.pl?mission=ISS010&roll=E&frame=13088 ] (bottom) were acquired January 15, 2005 with a Kodak 760C digital camera using a 400 mm lens, and are provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. The International Space Station Program [ http://spaceflight.nasa.gov/home/index.html ] supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. [ http://eol.jsc.nasa.gov/ ] |
|
Earthquake Spawns Tsunamis
| Title |
Earthquake Spawns Tsunamis |
| Description |
On December 26, 2004, a large (magnitude 9.0) earthquake occurred off the western coast of Sumatra in the Indian Ocean. The earthquake was caused by the release of stresses accumulated as the Burma tectonic plate overrides the India tectonic plate. Movement of the seafloor due to the earthquake generated a tsunami, or seismic sea wave, that affected coastal regions around the Indian Ocean. The northwestern Sumatra coastline in particular suffered extensive damage and loss of life. These astronaut photographs illustrate damage along the southwestern coast of Aceh Province in the vicinity of the city of Lho? Kruet, Indonesia. Large areas of bare and disturbed soil (brownish gray) that were previously covered with vegetation are visible along the coastline in the near-nadir (top) image. Embayments in the coastline were particularly hard hit, while adjacent headlands were less affected. The oblique (lower) astronaut photograph was acquired 45 seconds after the near-nadir photograph, and captures sunglint illuminating the Indian Ocean and standing water inland (light gray, yellow). Distortion and scale differences in the images are caused by increased obliquity of the view from the International Space Station. Arrows on the photographs indicate several points of comparison between the two images. Standing bodies of seawater may inhibit revegetation of damaged areas and act as sources of salt contamination in soil and groundwater. Astronaut photographs ISS010-E-13079 [ http://eol.jsc.nasa.gov/scripts/sseop/photo.pl?mission=ISS010&roll=E&frame=13079 ] (top) and ISS010-E-13088 [ http://eol.jsc.nasa.gov/scripts/sseop/photo.pl?mission=ISS010&roll=E&frame=13088 ] (bottom) were acquired January 15, 2005 with a Kodak 760C digital camera using a 400 mm lens, and are provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. The International Space Station Program [ http://spaceflight.nasa.gov/home/index.html ] supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. [ http://eol.jsc.nasa.gov/ ] |
|
North Reef Island, Andaman S
| Title |
North Reef Island, Andaman Sea |
| Description |
On December 26, 2004, one of the largest earthquakes in recorded history struck offshore of the island of Sumatra, Indonesia. The ocean floor heaved in some places and sank in others, creating catastrophic tsunamis that raced across the Indian Ocean. Hundreds of thousands of people died as the waves struck coastlines from Thailand to Sri Lanka to Somalia. In addition to tsunami damage, satellite images of reefs, islands, and coastlines identified signs of permanent elevation change—sinking or uplift—along the fault between the Indo-Australia and Burma plates. [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=12640 ] In places such as North Reef Island, shown in this pair of images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite, the quake lifted the reefs permanently out of the water. The images use visible and infrared light detected by ASTER to make different land surfaces stand out clearly from one another: water is blue, vegetation is red, coral or bare sand appears white. In the "before" image, from December 2, 2004, the submerged reef creates a bright blue glow around the island. In the "after" image, from February 4, 2005, the white coral stands completely up out of the water. It is even tinged with red, which suggests the exposed coral had died, and algae had colonized it. In the weeks and months after the earthquake, satellite images provided broad coverage of an area where ground-based observations were initially very limited. A team of scientists led by Caltech Ph.D. geology student Aron Meltzner discovered changes in elevation along nearly 1,600 kilometers (994 miles) of the tectonic plate boundary. The images revealed that the earthquake rupture extended 100 kilometers (62 miles) farther north than estimates based on seismic and Global Positioning System (GPS) data suggested. The feature article Rise and Fall: Satellites Reveal Full Length of Tsunami-Generating Earthquake [ http://earthobservatory.nasa.gov/Study/Aceh/aceh.html ] describes how scientists used satellite images to map the length of the earthquake rupture zone. The article includes additional satellite and ground-based images of elevation changes resulting from the 2004 Aceh-Andaman earthquake. NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
|
North Reef Island, Andaman S
| Title |
North Reef Island, Andaman Sea |
| Description |
On December 26, 2004, one of the largest earthquakes in recorded history struck offshore of the island of Sumatra, Indonesia. The ocean floor heaved in some places and sank in others, creating catastrophic tsunamis that raced across the Indian Ocean. Hundreds of thousands of people died as the waves struck coastlines from Thailand to Sri Lanka to Somalia. In addition to tsunami damage, satellite images of reefs, islands, and coastlines identified signs of permanent elevation change—sinking or uplift—along the fault between the Indo-Australia and Burma plates. [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=12640 ] In places such as North Reef Island, shown in this pair of images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) [ http://asterweb.jpl.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite, the quake lifted the reefs permanently out of the water. The images use visible and infrared light detected by ASTER to make different land surfaces stand out clearly from one another: water is blue, vegetation is red, coral or bare sand appears white. In the "before" image, from December 2, 2004, the submerged reef creates a bright blue glow around the island. In the "after" image, from February 4, 2005, the white coral stands completely up out of the water. It is even tinged with red, which suggests the exposed coral had died, and algae had colonized it. In the weeks and months after the earthquake, satellite images provided broad coverage of an area where ground-based observations were initially very limited. A team of scientists led by Caltech Ph.D. geology student Aron Meltzner discovered changes in elevation along nearly 1,600 kilometers (994 miles) of the tectonic plate boundary. The images revealed that the earthquake rupture extended 100 kilometers (62 miles) farther north than estimates based on seismic and Global Positioning System (GPS) data suggested. The feature article Rise and Fall: Satellites Reveal Full Length of Tsunami-Generating Earthquake [ http://earthobservatory.nasa.gov/Study/Aceh/aceh.html ] describes how scientists used satellite images to map the length of the earthquake rupture zone. The article includes additional satellite and ground-based images of elevation changes resulting from the 2004 Aceh-Andaman earthquake. NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
|
Thunderstorm over the Indian
| Title |
Thunderstorm over the Indian Ocean |
| Description |
On January 24, 2007, a minor cloud system blossomed in the Indian Ocean between Indonesia and northwestern Australia. The storm lacked the circulation of a tropical storm, so it never received a name. It did not strike any major populated centers, so it never was a news item. But newsworthy and fascinating are not always the same thing, and the symmetrical shape of the storm and the apparently expanding ring of cloud ripples shown in this image suggest some intriguing atmospheric physics in action. This photo-like image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] on the Terra [ http://terra.nasa.gov/ ] satellite on January 24, 2007, at 10:10 a.m. local time (2:10 UTC). The circular cloud system in the image was driven by powerful thunderstorms that previously raged beneath the now-ragged cirrus clouds at the system's center. The clouds formed from an afternoon convection system, a vigorous overturning of the air that is common this time of year near Australia's tropical northern coast. The system traveled westward over Austalia's Northern Territory, eventually reaching the coast of Western Australia. Over the Indian Ocean, the cloud system grew rapidly, drawing warm, moist ocean air up into the top of the storm. At the top of this convection system, the air ceased to flow upward and spilled out into an expanding ring. This same process almost always occurs in thunderstorms, but in this case there appears to have been relatively constant wind through a deep layer of the atmosphere, allowing the uplifted air to spread out equally in all directions. The clouds at the top of the storm dispersed as an expanding disk of cirrus cloud. The outflowing air may also have disturbed and amplified existing clouds, making them more reflective. Increased reflection of sunlight makes the clouds seem more brightly white to the MODIS sensor. NASA image by Jesse Allen, Earth Observatory, using data provided courtesy of the MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center. Image interpretation provided by George Huffman, NASA Goddard Space Flight Center. |
|
Flooding and Landslides in I
nasa, nasanaturalhazards
Persistent heavy rains led t
indonesia_trmm_2008002
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008-01-02 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
indonesia_trmm_2008002 |
|
Thunderstorm over the Indian
nasa, nasanaturalhazards
On January 24, 2007, a minor
nwaust_tmo_2007024
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-01-24 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
nwaust_tmo_2007024 |
|
Heavy Rainfall Floods Indone
nasa, nasaimageofthedaygalle
Persistent heavy rains led t
ge_08376
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-12-24 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08376 |
|
Heavy Rainfall Floods Indone
nasa, nasaimageofthedaygalle
Persistent heavy rains led t
ge_08376
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-12-24 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08376 |
|
Heavy Rainfall Floods Indone
nasa, nasaimageofthedaygalle
Persistent heavy rains led t
ge_08376
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-12-24 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08376 |
|
El Nino and Rainfall: Image
nasa, nasaimageofthedaygalle
At the end of 2006, East Afr
precipanom_trmm_200611
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006 |
| creator |
NASA -- NASA image created by Jesse Allen, Earth Observatory, using rainfall data provided courtesy of the precip.gsfc.nasa.gov/ Global Precipitation Climatology Product team at NASA Goddard Space Flight Center. |
| identifier |
precipanom_trmm_200611 |
|
North Reef Island, Andaman S
nasa, nasaimageofthedaygalle
On December 26, 2004, one of
nreefis_ast_2005035
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-02-04 |
| creator |
NASA -- NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan asterweb.jpl.nasa.gov/ ASTER Science Team. |
| identifier |
nreefis_ast_2005035 |
|
NASA Satellite Tracks Hazard
nasa, nasaimageofthedaygalle
New research sponsored by NA
toms_indonesia_smog
| mediatype |
IMAGE |
| mediatype |
image |
| date |
1997-10-22 |
| creator |
NASA -- Image courtesy NASA GSFC svs.gsfc.nasa.gov/ Scientific Visualization Studio, based on data from TOMS. |
| identifier |
toms_indonesia_smog |
|
La Nina Greenup Patterns: Im
nasa, nasaimageofthedaygalle
La Nina's fingerprint is all
ge_08575_02
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08575_02 |
|
La Nina Greenup Patterns: Im
nasa, nasaimageofthedaygalle
La Nina's fingerprint is all
ge_08575_02
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08575_02 |
|
La Nina Greenup Patterns: Im
nasa, nasaimageofthedaygalle
La Nina's fingerprint is all
ge_08575_02
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08575_02 |
|
La Nina Greenup Patterns: Im
nasa, nasaimageofthedaygalle
La Nina's fingerprint is all
ge_08575_02
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08575_02 |
|
La Nina Greenup Patterns: Im
nasa, nasaimageofthedaygalle
La Nina's fingerprint is all
ge_08575_02
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08575_02 |
|
La Nina Greenup Patterns: Im
nasa, nasaimageofthedaygalle
La Nina's fingerprint is all
ge_08575_02
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2008 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08575_02 |
|
La Nina Rainfall Patterns: I
nasa, nasaimageofthedaygalle
La Nina, the counterpart to
ge_08420
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-12-19 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08420 |
|
La Nina Rainfall Patterns: I
nasa, nasaimageofthedaygalle
La Nina, the counterpart to
ge_08420
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-12-19 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08420 |
|
La Nina Rainfall Patterns: I
nasa, nasaimageofthedaygalle
La Nina, the counterpart to
ge_08420
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-12-19 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08420 |
|
Uplift and Subsidence Associ
PIA02435
Sol (our sun)
ASTER
| Title |
Uplift and Subsidence Associated with the Great Aceh-Andaman Earthquake of 2004 |
| Original Caption Released with Image |
The magnitude 9.2 Indian Ocean earthquake of December 26, 2004, produced broad regions of uplift and subsidence. In order to define the lateral extent and the downdip limit of rupture, scientists from Caltech, Pasadena, Calif., NASA's Jet Propulsion Laboratory, Pasadena, Calif., Scripps Institution of Oceanography, La Jolla, Calif., the U.S. Geological Survey, Pasadena, Calif., and the Research Center for Geotechnology, Indonesian Institute of Sciences, Bandung, Indonesia, first needed to define the pivot line separating those regions. Interpretation of satellite imagery and a tidal model were one of the key tools used to do this. These pre-Sumatra earthquake (a) and post-Sumatra earthquake (b) images of North Sentinel Island in the Indian Ocean, acquired from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra spacecraft, show emergence of the coral reef surrounding the island following the earthquake. The tide was 30 plus or minus 14 centimeters lower in the pre-earthquake image (acquired November 21, 2000) than in the post-earthquake image (acquired February 20, 2005), requiring a minimum of 30 centimeters of uplift at this locality. Observations from an Indian Coast Guard helicopter on the northwest coast of the island suggest that the actual uplift is on the order of 1 to 2 meters at this site. In figures (c) and (d), pre-earthquake and post-earthquake ASTER images of a small island off the northwest coast of Rutland Island, 38 kilometers east of North Sentinel Island, show submergence of the coral reef surrounding the island. The tide was higher in the pre-earthquake image (acquired January 1, 2004) than in the post-earthquake image (acquired February 4, 2005), requiring subsidence at this locality. The pivot line must run between North Sentinel and Rutland islands. Note that the scale for the North Sentinel Island images differs from that for the Rutland Island images. The tidal model used for this study was based on data from JPL's Topex/Poseidon satellite. The model was used to determine the relative sea surface height at each location at the time each image was acquired, a critical component used to quantify the deformation. The scientists' method of using satellite imagery to recognize changes in elevation relative to sea surface height and of using a tidal model to place quantitative bounds on coseismic uplift or subsidence is a novel approach that can be adapted to other forms of remote sensing and can be applied to other subduction zones in tropical regions. 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. |
|
Volcanoes, Central Java, Ind
| Title |
Volcanoes, Central Java, Indonesia |
| Description |
The island of Java (8.0S, 112.0E), perhaps better than any other, illustrates the volcanic origin of Pacific Island groups. Seen in this single view are at least a dozen once active volcano craters. Alignment of the craters even defines the linear fault line of Java as well as the other some 1500 islands of the Indonesian Archipelago. Deep blue water of the Indian Ocean to the south contrasts to the sediment laden waters of the Java Sea to the north. |
| Date Taken |
1992-08-08 |
|
|