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Mount St. Helens
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Mount St. Helens |
| Description |
After more than a decade of inactivity, Mt. St. Helens in Washington began rumbling in late September with a series of small earthquakes, some of which were of the long-period type that geologists have come to recognize as the telltale sign that magma from the Earth?s interior is rising up to the surface. On October 1, 2004, the volcano released a small explosion of steam and ash and briefly quieted down, but in the days since, the earthquake activity resumed. Scientists raised the volcano?s alert level to three, the final step below active eruption. On October 4, the day this image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA?s Terra satellite, Mt. St. Helens again emitted steam and ash: during a 30-minute episode in the morning and for a 10-minute episode in the early afternoon. According to reports form the U.S. Geological Survey, the steam was likely produced by hot rock pushed up onto the mountain?s glacier that melted the ice and generated steam. Mt. St. Helens is located to the left of the center of this image, and the ash and steam plume are visible drifting away from the volcano to the southeast, toward the glacier-covered peak of Mt. Adams. Other large mountains in the scene are Mt. Rainer (top) and Mt. Hood (bottom). The Columbia River cuts east-west through the lower part of the image, and the city of Portland appears as a gray patch along its banks at lower left. Other signs that an eruption is likely in the near future are a bubbling (boiling) lake that has formed in the vent where the ash and steam were released on October 4, a quick return to earthquake activity following the emission episodes, the continued rising of part of the glacier and the south flank of the lava dome, opening cracks in the lava dome, and the detection of carbon dioxide and hydrogen sulfide gases at numerous sites. For more information on the current status of the volcano, please visit the U.S.G.S. Cascades Volcano Observatory [ http://vulcan.wr.usgs.gov/News/ ]Website. NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team, NASA-GSFC |
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Toxic Algal Bloom off Washin
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| Title |
Toxic Algal Bloom off Washington |
| Description |
Thriving ocean plants form clouds of green in the waters of the Pacific along the coast of Washington and Vancouver Island. On September 29, 2004, researchers from the University of Washington and NOAA reported finding a large bloom of Pseudo-nitzschia, a toxic algae, off the Strait of Juan de Fuca, the channel of water that separates Vancouver Island in the north from Washington State in the south. Fed by cold ocean waters that rise from the ocean floor near the coast, phytoplankton blooms are frequent in this region, and some are toxic. At about 48 kilometers (30 miles) across, this bloom is the largest toxic algae bloom ever observed near the Juan de Fuca Strait. On October 1, 2004, the Sea-viewing Wide Field-of-view Sensor aboard the OrbView-2 satellite detected high concentrations of chlorophyll in the Pacific Ocean. Not all of the chlorophyll seen in the right image is from the toxic bloom. It is likely that other forms of phytoplankton also color the water, and from this image alone, it is impossible to tell which are toxic algae and which are other plants. On September 29, the toxic bloom was reported to be about 24 kilometers (15 miles) off the northwest coast of Washington. NASA images courtesy the SeaWiFS Project [ http://seawifs.gsfc.nasa.gov/SEAWIFS.html ], NASA/Goddard Space Flight Center, and ORBIMAGE [ http://www.orbimage.com/ ]. |
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Toxic Algal Bloom off Washin
…
| Title |
Toxic Algal Bloom off Washington |
| Description |
Thriving ocean plants form clouds of green in the waters of the Pacific along the coast of Washington and Vancouver Island. On September 29, 2004, researchers from the University of Washington and NOAA reported finding a large bloom of Pseudo-nitzschia, a toxic algae, off the Strait of Juan de Fuca, the channel of water that separates Vancouver Island in the north from Washington State in the south. Fed by cold ocean waters that rise from the ocean floor near the coast, phytoplankton blooms are frequent in this region, and some are toxic. At about 48 kilometers (30 miles) across, this bloom is the largest toxic algae bloom ever observed near the Juan de Fuca Strait. On October 1, 2004, the Sea-viewing Wide Field-of-view Sensor aboard the OrbView-2 satellite detected high concentrations of chlorophyll in the Pacific Ocean. Not all of the chlorophyll seen in the right image is from the toxic bloom. It is likely that other forms of phytoplankton also color the water, and from this image alone, it is impossible to tell which are toxic algae and which are other plants. On September 29, the toxic bloom was reported to be about 24 kilometers (15 miles) off the northwest coast of Washington. NASA images courtesy the SeaWiFS Project [ http://seawifs.gsfc.nasa.gov/SEAWIFS.html ], NASA/Goddard Space Flight Center, and ORBIMAGE [ http://www.orbimage.com/ ]. |
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Toxic Algal Bloom off Washin
…
| Title |
Toxic Algal Bloom off Washington |
| Description |
Thriving ocean plants form clouds of green in the waters of the Pacific along the coast of Washington and Vancouver Island. On September 29, 2004, researchers from the University of Washington and NOAA reported finding a large bloom of Pseudo-nitzschia, a toxic algae, off the Strait of Juan de Fuca, the channel of water that separates Vancouver Island in the north from Washington State in the south. Fed by cold ocean waters that rise from the ocean floor near the coast, phytoplankton blooms are frequent in this region, and some are toxic. At about 48 kilometers (30 miles) across, this bloom is the largest toxic algae bloom ever observed near the Juan de Fuca Strait. On October 1, 2004, the Sea-viewing Wide Field-of-view Sensor aboard the OrbView-2 satellite detected high concentrations of chlorophyll in the Pacific Ocean. Not all of the chlorophyll seen in the right image is from the toxic bloom. It is likely that other forms of phytoplankton also color the water, and from this image alone, it is impossible to tell which are toxic algae and which are other plants. On September 29, the toxic bloom was reported to be about 24 kilometers (15 miles) off the northwest coast of Washington. NASA images courtesy the SeaWiFS Project [ http://seawifs.gsfc.nasa.gov/SEAWIFS.html ], NASA/Goddard Space Flight Center, and ORBIMAGE [ http://www.orbimage.com/ ]. |
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