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Hydrogen Sulfide Eruption of
…
| Title |
Hydrogen Sulfide Eruption off Namibia |
| Description |
The brilliant burst of neon blue and green that hugs the shore of Namibia in this photo-like image might be beautiful from space, but it is deadly on the ground. The color is caused by hydrogen sulfide erupting to the surface. The foul-smelling gas is toxic by itself, but it also robs the water of oxygen when it erupts to the surface, leading to large fish kills. Ironically, it is the ocean's productivity in this region that causes the deadly eruptions. Strong ocean currents sweep nutrient-rich water to the sunlit surface of the Atlantic Ocean off the coast of Namibia. The ample supply of nutrients allows tiny free-floating plants (phytoplankton) to proliferate. When the large phytoplankton blooms die, the plants sink to the ocean floor, where bacteria break them down. The anaerobic bacteria that complete the decay process release toxic hydrogen sulfide into the ocean. The gas builds near the ocean floor until a bubble erupts to the surface. As it rises, the hydrogen combines with oxygen to form water molecules, leaving solid, yellow sulfur. The sulfur scatters yellow light, lending the water a brilliance that can range from milky white to electric blue. This particular eruption surrounds Walvis Bay and stretches north along the Skeleton Coast and south to the orange dune fields of the Namib Desert. The city of Walvis Bay is a faint gray discoloration on the southern shore of the bay. The Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) flying on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured this image on July 25, 2007. The large image provided above has a resolution of 250 meters per pixel. The MODIS Rapid Response System provides the image in additional resolutions. Image courtesy Jeff Schmaltz, MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC |
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Hydrogen Sulfide Eruptions A
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| Title |
Hydrogen Sulfide Eruptions Along the Coast of Namibia |
| Description |
People living along Namibia?s desert coast have long been familiar with the rotten egg smell that periodically emanates from the Atlantic Ocean. With an economy that is largely based on fishing, the locals are also used to seeing millions of fish die whenever the unpleasant scent fills the air. The smell and the fish die-off are caused by hydrogen sulfide erupting from decaying plants on the sea floor. In the southeast Atlantic Ocean, strong ocean currents carry nutrient-rich deep-ocean water to the surface. The waters nourish free-floating microscopic plants, called phytoplankton, and other sea life. When the plants die, they sink to the ocean floor where bacteria begin to break them down. The oxygen is quickly used in the decay process, and anaerobic bacteria take over. These bacteria emit hydrogen sulfide gas as a by-product. The gas builds on the ocean floor until it erupts suddenly. When it reaches the surface, the hydrogen combines with oxygen to form water, allowing solid white sulfur to precipitate into the ocean. Of itself, hydrogen sulfide gas is toxic to fish, but this reaction with oxygen also creates deadly low-oxygen conditions in the ocean. The reaction at the surface also makes hydrogen sulfide eruptions visible in satellite imagery. The white sulfur reflects light, tinting the water bright green along the Namibian coast. On May 12, 2004, the Moderate Resolution Imaging Spectroradiometer [ http://modis.gsfc.nasa.gov ] (MODIS) on NASA?s Terra [ http://terra.nasa.gov/ ] satellite captured this image of a hydrogen sulfide eruption in progress. Along the coast, milky green sections of ocean show where hydrogen sulfide gas is coming up. Offshore, a phytoplankton bloom forms a bright green swirl in the ocean water, proof of the productivity that triggers the deadly eruptions. Both the image above and the full image are at MODIS? maximum resolution of 250 meters per pixel. The image is available in additional resolutions [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2004133-0512/Namibia.A2004133.0905 ]. NASA GSFC image courtesy Jacques Descloitres, MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] |
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Phytoplankton Bloom off Nami
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| Title |
Phytoplankton Bloom off Namibia |
| Description |
A flash of blue and green lit the waters off Namibia in early November 2007 as a phytoplankton bloom grew and faded in the Atlantic Ocean. The Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured this photo-like image on November 8, 2007. The bloom stretches from north to south along hundreds of kilometers, though it is brightest in the center of this image. Such blooms are common in the coastal waters off southwest Africa where cold, nutrient-rich currents sweep north from Antarctica and interact with the coastal shelf. At the same time, the easterly trade winds push surface water away from the shore, allowing water from the ocean's floor to rise to the surface, bringing with it iron and other material. The suffusion of nutrients from both the currents and upwelling water creates an environment where tiny surface-dwelling ocean plants (phytoplankton) thrive. Phytoplankton blooms are so abundant off Namibia that their death and decomposition often robs the water of dissolved oxygen. As the plants die, they sink to the ocean floor where bacteria consume them. There is so much plant material that the bacteria use all of the oxygen available int he water before they finish breaking down the plants, creating a dead-zone in the water where fish can't survive. Anaerobic bacteria, which don't require oxygen, take over in the decomposition process, releasing sulfur dioxide as a byproduct. The sulfur dioxide interacts with the ocean water to create solid sulfur and hydrogen sulfide, a poisonous gas, which eventually erupts to the surface, sometimes killing fish. Though no eruption is readily apparent in this image, hydrogen sulfide eruptions are often visible in satellite imagery because the solid sulfur colors the water a milky yellow-green. The bloom shown here persisted over several days. It first became distinct on October 28 [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NBenguela/2007301 ] (though clouds covered the region on previous days, so it may have developed earlier) and was just beginning to fade on November 14. [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NBenguela/2007318 ] The daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?NBenguela/2007312 ] provided by the MODIS Rapid Response System show the bloom growing and fading throughout that period. You can download a 250-meter-resolution KMZ file of the bloom [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Nov2007/namibia_amo_2007312.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Streamers of Dust off Namibi
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| Title |
Streamers of Dust off Namibia |
| Description |
Streamers of dust were hanging in the air over the Atlantic Ocean off the coast of Namibia on June 24, 2003. This image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite. The high-resolution image provided above is 500 meters per pixel. The MODIS Rapid Response System provides this image at MODIS' maximum spatial resolution of 250 meters. Image courtesy Jeff Schmaltz, MODIS Rapid Response Team, NASA GSFC |
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Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date |
06.26.1983 |
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Phytoplankton Bloom off Nami
…
nasa, nasanaturalhazards
A flash of blue and green li
…
namibia_amo_2007312
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-11-08 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
namibia_amo_2007312 |
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Hydrogen Sulfide Eruption of
…
nasa, nasanaturalhazards
The brilliant burst of neon
…
Namibia_AMO_2007206
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-07-25 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Namibia_AMO_2007206 |
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Phytoplankton Bloom off Nami
…
nasa, nasaimageofthedaygalle
…
A flash of blue and green li
…
ge_08246
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-11-08 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_08246 |
|
Historic Tropical Cyclone Tr
…
nasa, nasaimageofthedaygalle
…
Like streamers of splattered
…
tropical_cyclone_map
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006 |
| creator |
NASA -- www.globalwarmingart.com/wiki/Image:Tropical_Storm_Map_png Image by Robert A. Rohde, www.globalwarmingart.com/wiki/ Global Warming Art. |
| identifier |
tropical_cyclone_map |
|
Hydrogen Sulfide Eruptions A
…
nasa, nasanaturalhazards
People living along Namibia'
…
ge_13155
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-05-12 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_13155 |
|
Hydrogen Sulfide Eruptions A
…
nasa, nasanaturalhazards
People living along Namibia'
…
ge_13155
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2004-05-12 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_13155 |
|
STS-32 Earth observation of
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| Title |
STS-32 Earth observation of the southern Sand Sea, Namibia, Atlantic Ocean |
| Description |
STS-32 Earth observation taken onboard Columbia, Orbiter Vehicle (OV) 102, is of the southern Sand Sea. Low sun angles on this south-looking view of the sand dunes of the southern Sand Sea (foreground) shows the many subtle patterns produced by winds. Along the coast very strong southerly winds have generated a zone of ribbed, transverse dunes. Further inland, different patterns appear, which may relate to present winds, or perhaps to winds which blew in different directions at times in the geological past. Strong Santa Ana-type winds blow from inland (left) during the winter which may explain the small patterns (center left). The small fishing port of Luderitz occupies the main bay on the coastline. Otherwise the area is empty of inhabitants on the very dry and windy coast. Railways connect the post with inland centers. |
| Date Taken |
1990-01-20 |
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Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
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