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A Summer View of Russia's Le
…
| Title |
A Summer View of Russia's Lena Delta and Olenek River |
| Description |
These views of the Russian Arctic were acquired by NASA's Multi-angle Imaging SpectroRadiometer (MISR) instrument on July 11, 2004. The brief arctic summer had transformed the frozen tundra and the thousands of lakes, channels, and rivers of the Lena Delta into a fertile wetland, and the usual blanket of thick snow had melted from the vast plains and taiga forests. The images show an area in the northern part of the Sakha Republic in eastern Siberia. The Olenek River wends northeast from the bottom of the images to the upper left, and the delta through which the mighty Lena River empties into the Laptev Sea dominate the top portions of the images. Creating accurate maps of vegetation structure is essential for understanding the seasonal exchanges of energy and water at the Earth's surface and for preserving biodiversity. The left-hand image is a natural-color image from MISR's nadir (vertical-viewing) camera, in which the rivers appear murky due to sediment, and photosynthetically active vegetation appears green. The center image is also from MISR's nadir camera, but is a false-color view in which the predominant red color is due to the brightness of vegetation at near-infrared wavelengths. Apart from the Lena Delta, the most photosynthetically active regions are within the lower half of the image and throughout the great stretch of land that curves across the Olenek River. The relatively barren ranges of the Volyoi Mountains appear as the pale tan-colored area to the right of image center. The right-hand image is a multiangle, false-color view made from the red band data of the 60-degree-backward, nadir, and 60-degree-forward cameras, displayed as red, green and blue, respectively. Water appears blue in this image because sun glint makes smooth, wet surfaces look brighter at the forward camera's view angle. Much of the landscape and many low clouds appear purple because these surfaces are both forward and backward scattering, and clouds that are further from the surface appear in a different spot for each view angle, creating a rainbow-like appearance. The highly vegetated region in the natural-color nadir image exhibits a faint greenish hue in the multi-angle composite. This subtle effect suggests that the nadir camera is observing more of the brighter, underlying surface than the oblique cameras, providing information about the distribution and density of trees and shrubs in this area. The Multiangle Imaging SpectroRadiometer observes the daylit Earth continuously, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. The MISR Browse Image Viewer [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://eosweb.larc.nasa.gov/MISRBR/ ], provides access to low-resolution true-color versions of these images. These data products were generated from a portion of the imagery acquired during Terra orbit 24273. The panels cover an area of about 230 kilometers x 420 kilometers, and utilize data from blocks 30 to 34 within World Reference System-2 path 134. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. [ http://www-misr.jpl.nasa.gov/ ] Text by Clare Averill (Raytheon/JPL). |
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Flooding in Siberia
| Title |
Flooding in Siberia |
| Description |
Nearly every year in the late spring, ice blocks the flow of water at the mouth of the Lena River in northeastern Russia and gives rise to floods across the Siberian plains. This year?s floods can be seen in this image taken on June 2, 2002, by the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard the Terra [ http://terra.nasa.gov/ ] satellite. The river runs down the left side of the image, and its delta is shrouded in ice (red) at the top of the image. Usually, the river would resemble a thin black line in MODIS imagery. The Lena River, which is Russia?s longest, flows 2,641 miles (4,250 kilometers) south to north through Siberia and into the Laptev Sea. In the winter, the river becomes nearly frozen. In the spring, however, water upstream thaws earlier than water at the mouth of the river. As the southern end of the river begins to melt, blocks of ice travel downstream to the frozen delta, pile up, and obstruct the flow of water. Flooding doesn?t always occur on the exact same parts of the river every spring. The floods hit further south last year [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=4895 ]. If the flooding grows severe enough, explosive charges are typically used to break up the ice jams. In these false-color images land areas are a dull, light green or tan, and water is black. Clouds appear pink, and ice comes across as bright red. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov/ ] at NASA GSFC |
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Flooding in Siberia
| Title |
Flooding in Siberia |
| Description |
Nearly every year in the late spring, ice blocks the flow of water at the mouth of the Lena River in northeastern Russia and gives rise to floods across the Siberian plains. The image above is a flood map of the river created by the Dartmouth Flood Observatory. The dark blue in the image demarcates the river, which was mapped using data from the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard NASA?s Terra satellite. The floods, which are depicted in a lighter blue, were mapped using data from the SeaWinds instrument aboard NASA?s QuikSCAT satellite. (The large imaged accessed by the link above and to the right was constructed using data from satellite instruments other than SeaWinds.) The Lena River, which is Russia?s longest, flows 2,641 miles (4,250 kilometers) south to north through Siberia and into the Laptev Sea. In the winter, the river becomes nearly frozen. In the spring, however, water upstream thaws earlier than water at the mouth of the river. As the southern end of the river begins to melt, blocks of ice travel downstream to the frozen delta, pile up, and obstruct the flow of water. Flooding doesn?t always occur on the exact the same parts of the river every each spring. The floods hit further south last year. If the flooding grows severe enough, explosive charges are typically used to break up the ice jams. This is the first time QuikSCAT/SeaWinds has been used to map a flood. The satellite, which sends out high frequency radio waves to detect the frothiness of water, was originally designed to measure wind speed and direction near the surface of the ocean. By employing it on floodwaters, scientists at the Dartmouth Flood Observatory hope to obtain much more accurate and timely measurements of the extent of floods around the world. The group, led by Robert Brakenridge, is constructing a worldwide atlas of flood maps such as these in order to outline the extent of the world?s flood plains. The idea is that if people are aware of where flood plains exist, they could then avoid building or settling on them. Image courtesy Robert Brakenridge, Dartmouth Flood Observatory at Dartmouth University. |
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Flooding in Siberia
| Title |
Flooding in Siberia |
| Description |
Nearly every year in the late spring, ice blocks the flow of water at the mouth of the Lena River in northeastern Russia and gives rise to floods across the Siberian plains. The image above is a flood map of the river created by the Dartmouth Flood Observatory. The dark blue in the image demarcates the river, which was mapped using data from the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard NASA?s Terra satellite. The floods, which are depicted in a lighter blue, were mapped using data from the SeaWinds instrument aboard NASA?s QuikSCAT satellite. (The large imaged accessed by the link above and to the right was constructed using data from satellite instruments other than SeaWinds.) The Lena River, which is Russia?s longest, flows 2,641 miles (4,250 kilometers) south to north through Siberia and into the Laptev Sea. In the winter, the river becomes nearly frozen. In the spring, however, water upstream thaws earlier than water at the mouth of the river. As the southern end of the river begins to melt, blocks of ice travel downstream to the frozen delta, pile up, and obstruct the flow of water. Flooding doesn?t always occur on the exact the same parts of the river every each spring. The floods hit further south last year. If the flooding grows severe enough, explosive charges are typically used to break up the ice jams. This is the first time QuikSCAT/SeaWinds has been used to map a flood. The satellite, which sends out high frequency radio waves to detect the frothiness of water, was originally designed to measure wind speed and direction near the surface of the ocean. By employing it on floodwaters, scientists at the Dartmouth Flood Observatory hope to obtain much more accurate and timely measurements of the extent of floods around the world. The group, led by Robert Brakenridge, is constructing a worldwide atlas of flood maps such as these in order to outline the extent of the world?s flood plains. The idea is that if people are aware of where flood plains exist, they could then avoid building or settling on them. Image courtesy Robert Brakenridge, Dartmouth Flood Observatory at Dartmouth University. |
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Flooding on the Lena River,
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| Title |
Flooding on the Lena River, Russia |
| Description |
*full-size images:* May 22, 2001 (1.4 MB) May 28, 2001 (1.4 MB) What a difference a week can make! This pair of true-color images acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS) on NASA's Terra [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://terra.nasa.gov/ ] satellite show the spring thaw and resulting flooding of the Lena River, a principal waterway of eastern Siberia. The first image, acquired on May 22, 2001, shows the Lena as a mostly frozen, white ribbon running north. An eastward flowing tributary, the Vilyuy, also appears frozen. In the second image, taken only 8 days later, large sections of the Lena, as well as the Vilyuy appear to be almost completely thawed. The formerly white ribbon of the river now appears decidedly brown, likely indicating sediment churned up by high water. The region is experiencing its worst flooding in one hundred years, with hundreds of thousands of people being affected by the floodwaters that have resulted from the melting of the snow pack accumulated over a particularly harsh Siberian winter. Explosives are being detonated in many places to dislodge huge blocks of ice that are backing up rivers and exacerbating flooding. The Lena River is one of the longest rivers in the world. It flows northeast and then north from its source in the Baikal Mountains south of the Central Siberian Plateau, and it empties into the Arctic Ocean via the Laptev Sea. At the mouth of the Lena River is a delta that is about 250 miles wide. The delta is frozen tundra for about 7 months of the year, but spring transforms the region into a lush wetland for the remainder of the year. Part of the area is protected as part of the Lena Delta Wildlife Reserve. Image courtesy Jacques Descloitres, MODIS Land [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://modland.nascom.nasa.gov/ ] Rapid Response Team |
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Flooding on the Lena River,
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| Title |
Flooding on the Lena River, Russia |
| Description |
*full-size images:* May 22, 2001 (1.4 MB) May 28, 2001 (1.4 MB) What a difference a week can make! This pair of true-color images acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS) on NASA's Terra [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://terra.nasa.gov/ ] satellite show the spring thaw and resulting flooding of the Lena River, a principal waterway of eastern Siberia. The first image, acquired on May 22, 2001, shows the Lena as a mostly frozen, white ribbon running north. An eastward flowing tributary, the Vilyuy, also appears frozen. In the second image, taken only 8 days later, large sections of the Lena, as well as the Vilyuy appear to be almost completely thawed. The formerly white ribbon of the river now appears decidedly brown, likely indicating sediment churned up by high water. The region is experiencing its worst flooding in one hundred years, with hundreds of thousands of people being affected by the floodwaters that have resulted from the melting of the snow pack accumulated over a particularly harsh Siberian winter. Explosives are being detonated in many places to dislodge huge blocks of ice that are backing up rivers and exacerbating flooding. The Lena River is one of the longest rivers in the world. It flows northeast and then north from its source in the Baikal Mountains south of the Central Siberian Plateau, and it empties into the Arctic Ocean via the Laptev Sea. At the mouth of the Lena River is a delta that is about 250 miles wide. The delta is frozen tundra for about 7 months of the year, but spring transforms the region into a lush wetland for the remainder of the year. Part of the area is protected as part of the Lena Delta Wildlife Reserve. Image courtesy Jacques Descloitres, MODIS Land [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://modland.nascom.nasa.gov/ ] Rapid Response Team |
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Flooding on the Lena River,
…
| Title |
Flooding on the Lena River, Russia |
| Description |
*full-size images:* May 22, 2001 (1.4 MB) May 28, 2001 (1.4 MB) What a difference a week can make! This pair of true-color images acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS) on NASA's Terra [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://terra.nasa.gov/ ] satellite show the spring thaw and resulting flooding of the Lena River, a principal waterway of eastern Siberia. The first image, acquired on May 22, 2001, shows the Lena as a mostly frozen, white ribbon running north. An eastward flowing tributary, the Vilyuy, also appears frozen. In the second image, taken only 8 days later, large sections of the Lena, as well as the Vilyuy appear to be almost completely thawed. The formerly white ribbon of the river now appears decidedly brown, likely indicating sediment churned up by high water. The region is experiencing its worst flooding in one hundred years, with hundreds of thousands of people being affected by the floodwaters that have resulted from the melting of the snow pack accumulated over a particularly harsh Siberian winter. Explosives are being detonated in many places to dislodge huge blocks of ice that are backing up rivers and exacerbating flooding. The Lena River is one of the longest rivers in the world. It flows northeast and then north from its source in the Baikal Mountains south of the Central Siberian Plateau, and it empties into the Arctic Ocean via the Laptev Sea. At the mouth of the Lena River is a delta that is about 250 miles wide. The delta is frozen tundra for about 7 months of the year, but spring transforms the region into a lush wetland for the remainder of the year. Part of the area is protected as part of the Lena Delta Wildlife Reserve. Image courtesy Jacques Descloitres, MODIS Land [ http://earthobservatory.nasa.gov/cgi-bin/redirect?http://modland.nascom.nasa.gov/ ] Rapid Response Team |
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Flooding on Russia's Lena Ri
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nasa, nasaimageofthedaygalle
…
Nearly every year in the lat
…
Russia.A2002153.0245
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2002-06-02 |
| creator |
NASA -- Image courtesy Jacques Descloitres, rapidfire.sci.gsfc.nasa.gov/ MODIS Land Rapid Response Team at NASA GSFC |
| identifier |
Russia.A2002153.0245 |
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Lena River Delta, Russia: Im
…
nasa, nasaimageofthedaygalle
…
After a 4,400-kilometer (2,7
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ge_07343
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-07-16 |
| creator |
NASA -- Image courtesy of NASA/GSFC/MITI/ERSDAC/JAROS, and the U.S./Japan asterweb.jpl.nasa.gov/ ASTER Science Team. |
| identifier |
ge_07343 |
|
Lena River Delta, Russia: Im
…
nasa, nasaimageofthedaygalle
…
After a 4,400-kilometer (2,7
…
ge_07343
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2005-07-16 |
| creator |
NASA -- Image courtesy of NASA/GSFC/MITI/ERSDAC/JAROS, and the U.S./Japan asterweb.jpl.nasa.gov/ ASTER Science Team. |
| identifier |
ge_07343 |
|
Flooding on the Lena River,
…
nasa, nasaimageofthedaygalle
…
What a difference a week can
…
modis_lena_river_flood
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2001-05-22 |
| creator |
NASA -- Image courtesy Jacques Descloitres, modland.nascom.nasa.gov/ MODIS Land Rapid Response Team |
| identifier |
modis_lena_river_flood |
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Flooding in Siberia: Natural
…
nasa, nasanaturalhazards
Nearly every year in the lat
…
lena3_q2002
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2002-06-05 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
lena3_q2002 |
|
Flooding in Siberia: Natural
…
nasa, nasanaturalhazards
Nearly every year in the lat
…
lena3_q2002
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2002-06-05 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
lena3_q2002 |
|
Flooding in Siberia: Natural
…
nasa, nasanaturalhazards
Nearly every year in the lat
…
lena_m2002153
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2002-06-02 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
lena_m2002153 |
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A Summer View of Russia's Le
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PIA04366
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
A Summer View of Russia's Lena Delta and Olenek |
| Original Caption Released with Image |
24273. The panels cover an area of about 230 kilometers x 420 kilometers, and utilize data from blocks 30 to 34 within World Reference System-2 path 134. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology., These views of the Russian Arctic were acquired by NASA's Multi-angle Imaging SpectroRadiometer (MISR) instrument on July 11, 2004, when the brief arctic summer had transformed the frozen tundra and the thousands of lakes, channels, and rivers of the Lena Delta into a fertile wetland, and when the usual blanket of thick snow had melted from the vast plains and taiga forests. This set of three images cover an area in the northern part of the Eastern Siberian Sakha Republic. The Olenek River wends northeast from the bottom of the images to the upper left, and the top portions of the images are dominated by the delta into which the mighty Lena River empties when it reaches the Laptev Sea. At left is a natural color image from MISR's nadir (vertical-viewing) camera, in which the rivers appear murky due to the presence of sediment, and photosynthetically-active vegetation appears green. The center image is also from MISR's nadir camera, but is a false color view in which the predominant red color is due to the brightness of vegetation at near-infrared wavelengths. The most photosynthetically active parts of this area are the Lena Delta, in the lower half of the image, and throughout the great stretch of land that curves across the Olenek River and extends northeast beyond the relatively barren ranges of the Volyoi mountains (the pale tan-colored area to the right of image center). The right-hand image is a multi-angle false-color view made from the red band data of the 60º backward, nadir, and 60º forward cameras, displayed as red, green and blue, respectively. Water appears blue in this image because sun glitter makes smooth, wet surfaces look brighter at the forward camera's view angle. Much of the landscape and many low clouds appear purple since these surfaces are both forward and backward scattering, and clouds that are further from the surface appear in a different spot for each view angle, creating a rainbow-like appearance. However, the vegetated region that is darker green in the natural color nadir image, also appears to exhibit a faint greenish hue in the multi-angle composite. A possible explanation for this subtle green effect is that the taiga forest trees (or dwarf-shrubs) are not too dense here. Since the the nadir camera is more likly to observe any gaps between the trees or shrubs, and since the vegetation is not as bright (in the red band) as the underlying soil or surface, the brighter underlying surface results in an area that is relatively brighter at the nadir view angle. Accurate maps of vegetation structural units are an essential part of understanding the seasonal exchanges of energy and water at the Earth's surface, and of preserving the biodiversity in these regions. The Multiangle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82° north and 82° south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit |
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