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Floods in Northern Argentina
| Title |
Floods in Northern Argentina |
| Description |
One of South America's longest rivers, the Parana winds south from its headwaters in central Brazil through Paraguay and Argentina to empty into the Atlantic Ocean near Buenos Aires, Argentina. Near its mouth, the river widens into a multi-stream delta where it joins the Uruguay River to form the broad Rio de la Plata estuary. Small and neatly defined at the height of summer in mid-January, the delta section of the river stretched kilometers across its flood plain in response to unusually heavy late-summer and early-autumn rains by April. The top image, taken on April 3, 2007, shows that not only has the river expanded into a broad black band, but its tributaries are also swollen. Flecks of black south and west of the river show where water covers agricultural fields. These images, both collected by the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite, were made with a combination of visible and infrared light to increase the contrast between mud-colored water and land. In these images, water is black or dark blue, and clouds are pale blue and white. Plant-covered land is bright green, and bare earth is tan. In the lower image, taken at the height of the growing season, the agricultural fields are green. By April, the crops had been harvested and the land left bare. The slightly orange color suggests that the fields may have been burned to clear away the stubble. Hugging the west bank of the Parana River, the city of Rosario is a gray-colored spot on the landscape. The floods extend north beyond the top edge of this image, affecting nearly four million hectares (15,000 square miles) and more than 70,000 people in two Argentine states, said the United Nations Office for the Coordination of Humanitarian Affairs (OCHA [ http://www.reliefweb.int/rw/rwb.nsf/db900SID/MCON-6ZX4CN?OpenDocument ]). The flooding was amplified when up to 500 millimeters of rainmore than half the average yearly rainfallfell over northern Argentina in the span of a few days at the end of March, said OCHA. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Floods in Northern Argentina
| Title |
Floods in Northern Argentina |
| Description |
One of South America's longest rivers, the Parana winds south from its headwaters in central Brazil through Paraguay and Argentina to empty into the Atlantic Ocean near Buenos Aires, Argentina. Near its mouth, the river widens into a multi-stream delta where it joins the Uruguay River to form the broad Rio de la Plata estuary. Small and neatly defined at the height of summer in mid-January, the delta section of the river stretched kilometers across its flood plain in response to unusually heavy late-summer and early-autumn rains by April. The top image, taken on April 3, 2007, shows that not only has the river expanded into a broad black band, but its tributaries are also swollen. Flecks of black south and west of the river show where water covers agricultural fields. These images, both collected by the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite, were made with a combination of visible and infrared light to increase the contrast between mud-colored water and land. In these images, water is black or dark blue, and clouds are pale blue and white. Plant-covered land is bright green, and bare earth is tan. In the lower image, taken at the height of the growing season, the agricultural fields are green. By April, the crops had been harvested and the land left bare. The slightly orange color suggests that the fields may have been burned to clear away the stubble. Hugging the west bank of the Parana River, the city of Rosario is a gray-colored spot on the landscape. The floods extend north beyond the top edge of this image, affecting nearly four million hectares (15,000 square miles) and more than 70,000 people in two Argentine states, said the United Nations Office for the Coordination of Humanitarian Affairs (OCHA [ http://www.reliefweb.int/rw/rwb.nsf/db900SID/MCON-6ZX4CN?OpenDocument ]). The flooding was amplified when up to 500 millimeters of rainmore than half the average yearly rainfallfell over northern Argentina in the span of a few days at the end of March, said OCHA. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
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Fires and Thick Smoke over S
…
| Title |
Fires and Thick Smoke over South America |
| Description |
The skies over the heart of South America were thick with the smoke from thousands of fires on September 9, 2007. In this image from the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Aqua [ http://aqua.nasa.gov ], challenging for scientists to say what the overall effect of smoke on clouds and rainfall is. NASA's Terra [ http://terra.nasa.gov ] and Aqua [ http://aqua.nasa.gov ] satellites each have a MODIS sensor capable of detecting fires and mapping the extent of smoke aerosols on a daily basis. Scientists from around the world are using these data to advance our understanding of how natural and human-caused fires are changing our planet. NASA image created by Jesse Allen, using data provided courtesy of the MODIS Rapid Response [ http://rapidfire.sci.gsfc.nasa.gov/ ] team., satellite, locations where the sensor detected actively burning fires are marked with red dots. The skies are flooded with smoke, which pools along the eastern foothills of the Andes Mountains for thousands of kilometers. (North-to-south this image covers 3,050 kilometers, if we laid it over a map of the central United States, it would spill over the borders into both Canada and the Gulf of Mexico for at least a hundred kilometers in both directions.) Although naturally occurring fires are not uncommon in the drier forests and grasslands of South America, this type of intense, continent-spanning fire activity is almost certainly a product of human activities. Some fires are intentional, set by people to clear forest, savannas, and grasslands for ranching or farming. Other fires occur accidentally from human activities. Landscapes that have been disturbed by logging, fragmentation, or previous accidental fire are more prone to catch fire accidentally. In these situations, planned fires (such as brush clearing fires on already cleared land) can easily get out of control and invade other areas, especially during drought years. The image spans a variety of ecological regions. The top of the scene, including Peru, northern Bolivia, and western Brazil is home to the southernmost portions of the Amazon Rainforest. These wetter forests give way to the south to drier forests and more open woodlands in southern Bolivia, northwestern Paraguay and northern Argentina east of the Andes, this area is called the Chaco. In Uruguay and southern Brazil, the natural vegetation is savannas and grasslands. Even in ecosystems where fires occur naturally (the Chaco, savannas, and grasslands), human activities may change the frequency and intensity of fires. The number and different kinds of plants and animals may change as a result. And in the Amazon, naturally occurring fire was historically very rare, and trees and other plants have no real adaptations to fire. Fires in the rainforest have the potential to completely transform the Southern Amazon forests into a savanna. Fires influence not only the land surface, but the atmosphere as well. Research suggests that the impacts of smoke on the tropical atmosphere vary from place to place, season to season, and year to year. Studies have shown smoke reducing cloudiness over the Amazon itself, but not over the nearby ocean and not every year. The net impact on rainfall is also uncertain. Smoke particles suppress cloud formation by providing an over-abundance of condensation sites for water vapor. The water vapor spreads out over these particles, and it takes the cloud droplets longer to get big enough to fall as rain. The flip side, however, is that the smaller, lighter cloud droplets can rise much higher into the atmosphere, which ultimately invigorates updrafts, intensifies thunderstorms, and produces large hail and heavy rain. The competing effects in different areas and weather conditions make it extremely |
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Fires and Thick Smoke over S
…
| Title |
Fires and Thick Smoke over South America |
| Description |
Hundreds, possibly thousands of fires (locations marked in red) were burning in South America when the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Aqua [ http://aqua.nasa.gov ] satellite passed overhead on September 25, 2007, and captured this image. The most intense fire activity was in Bolivia, where fires are concentrated in the Santa Cruz Department, in the southeastern part of the country. Although naturally occurring fires can occur in the savannas and dry woodlands of southern Bolivia and northern Paraguay, this type of intense, widespread burning is likely the result of human activities. Agricultural fires (for example, fires for brush or crop-residue clearing) can get out of control and spread to surrounding forests and other natural areas. Thick smoke is hanging over much of the scene. The large image provided above has a spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response Team provides twice-daily [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?FAS_Bolivia ] images of the region in additional resolutions. NASA image courtesy the MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center |
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Fires and Thick Smoke over S
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nasa, nasanaturalhazards
Hundreds, possibly thousands
…
Bolivia_AMO_2007268
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-09-25 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
Bolivia_AMO_2007268 |
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Floods in Northern Argentina
…
nasa, nasanaturalhazards
* eoimages.gsfc.nasa.gov/ima
…
SParana_TMO_2007093
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-04-03 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
SParana_TMO_2007093 |
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Fires and Smoke Across South
…
nasa, nasaimageofthedaygalle
…
The skies over the heart of
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samerica_amo_2007252
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-09-09 |
| creator |
NASA -- NASA image created by Jesse Allen, using data provided courtesy of the rapidfire.sci.gsfc.nasa.gov/ MODIS Rapid Response team. |
| identifier |
samerica_amo_2007252 |
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Hundreds of Fires in Bolivia
…
nasa, nasaimageofthedaygalle
…
Hundreds, possibly thousands
…
ge_08077
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-09-25 |
| creator |
NASA -- NASA image courtesy the rapidfire.sci.gsfc.nasa.gov MODIS Rapid Response Team, Goddard Space Flight Center |
| identifier |
ge_08077 |
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