May 10th, 2012 Category: Fires, Image of the day, Wetlands

Brazil - May 8th, 2012

Close-up

Smoke from a fire in the Pantanal, by the Brazil-Bolivia-Paraguay border, can be observed by the center of the main image. The close-up shows the same fire at a slightly different time. In the former, the smoke has a V-shape due to changes in the direction of air currents, while in the latter the plume is blowing towards the northwest and a cloud of smoke can be observed in the lower left corner.

The Pantanal is a tropical wetland. It is one of the world’s largest wetlands of any kind. Most of it lies within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay, sprawling over an area estimated at between 140,000 square kilometres (54,000 sq mi) and 195,000 square kilometres (75,000 sq mi).

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March 29th, 2012 Category: Rivers, Salt Flats, Sediments, Wetlands

India - March 18th, 2012

Sediments can be seen in two large bays on the coast of India – the Gulf of Khambhat (east), famous for its extreme tides, and the Gulf of Kutch (west of the former), by the India-Pakistan border. Located near the Gulf of Kutch is the Rann of Kutch, an area of season salt marshes. Here, areas of salt flats appear bright white, while areas covered with deeper water or vegetation appear green. West of the Rann is the lower portion of the Indus River Valley, appearing as a thick green ribbon on either side of the Indus River.

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February 3rd, 2012 Category: Rivers, Wetlands

Pakistan - January 4th, 2012

Flowing down from the Tibetan plateau of western China, across the country of Pakistan in wide, sweeping curves, is the Indus River. It enters Pakistan via the Northern Areas (Gilgit-Baltistan), flowing through the North in a southerly direction along the entire length of Pakistan, to merge into the Arabian Sea near the port city of Karachi in Sindh, Pakistan. The total length of the river is 3,180 kilometers (1,980 mi) and it is Pakistan’s longest river.

Visible near the mouth of the river, to the east, is the Great Rann of Kutch, a seasonal salt marsh located in the Thar Desert in the Kutch District of Gujarat, India and the Sindh province of Pakistan. It comprises some 30,000 square kilometres (10,000 sq mi) between the Gulf of Kutch and the mouth of the Indus River in southern Pakistan. The area was a vast shallows of the Arabian Sea until continuing geological uplift closed off the connection with the sea, creating a vast lake that has since shrunk but floods seasonally during the monsoon.

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February 1st, 2012 Category: Wetlands

USA - December 27th, 2011

This orthorectified image shows Monterey Bay, a bay of the Pacific Ocean, along the central coast of California. The bay is south of San Francisco and San Jose, between the cities of Santa Cruz and Monterey. The Monterey Canyon, one of the largest underwater canyons in the world, begins off the coast of Moss Landing, exactly in the center of Monterey Bay.

Visible at the center right edge is Elkhorn Slough, a 17.1-mile-long (27.5 km) tidal slough and estuary on Monterey Bay. The community of Moss Landing and the huge Moss Landing Power Plant are located at the mouth of the slough on the bay. Elkhorn Slough harbors the largest tract of tidal salt marsh in California outside of San Francisco Bay and provides much-needed habitat for hundreds of species of plants and animals, including more than 340 species of birds.

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January 24th, 2012 Category: Rivers, Wetlands

Zambia - January 6th, 2012

The Barotse Floodplain, visible as a bright green area by the Zambezi River on the left side of this image, is one of Africa’s great wetlands and a designated Ramsar site. It is located in the Western Province of Zambia. The region is a flat plateau at an elevation of about 1000 m tilting very slightly to the south. The Zambezi and its headwaters rise on the higher ground to the north, which enjoys good rainfall (1400 mm annually) in a rainy season from October to May.

The floodplain stretches from the Zambezi’s confluence with the Kabompo and Lungwebungu Rivers in the north, to a point about 230 km south, above the Ngonye falls and south of Senanga. Along most of its length its width is over 30 km, reaching 50 km at the widest. The main body of the plain covers about 5500 km², but the maximum flooded area is 10 750 km² when the floodplains of several tributaries are taken into account.

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January 22nd, 2012 Category: Image of the day, Lakes, Rivers, Wetlands

Botswana - January 6th, 2012

The Okavango Delta (or Okavango Swamp), in Botswana, is the world’s largest inland delta. It is formed where the Okavango River empties onto a swamp in an endorheic basin in the Kalahari Desert, where most of the water is lost to evaporation and transpiration instead of draining into the sea. Each year approximately 11 cubic kilometres of water irrigate the 15,000 km² area.

The Okavango Delta is produced by seasonal flooding. The Okavango river drains the summer (January–February) rainfall from the Angola highlands and the surge flows 1,200 kilometres in approximately one month. The waters then spread over the 250 km by 150 km area of the delta over the next four months (March–June). The flood peaks between June and August, during Botswana’s dry winter months, when the delta swells to three times its permanent size. Some flood-waters drain into Lake Ngami, which is visible here at the center of the bottom edge.

Lake Ngami is an endorheic lake in Botswana north of the Kalahari Desert. It is seasonally filled by the Taughe River, an affluent of the Okavango River system flowing out of the western side of the Okavango Delta. It is one of the fragmented remnants of the ancient Lake Makgadikgadi. Although the lake has shrunk dramatically beginning from 1890, it remains an important habitat for birds and wildlife, especially in flood years.

Tags: Botswana Kalahari Desert Lake Ngami Okavango Delta Okavango Swamp Taughe River | | Leave a comment

January 18th, 2012 Category: Rivers, Wetlands

USA - January 5th, 2012

The bright white area in the upper part of this orthorectified wide-swath ASAR image is Philadelphia, the largest city in the Commonwealth of Pennsylvania. The city is located in the Northeastern United States along the Delaware and Schuylkill rivers. It is the fifth-most-populous city in the United States, with a population of 1,526,006 as of the 2010 U.S. Census.

According to the United States Census Bureau, the city has a total area of 142.6 square miles (369.3 km2), of which 135.1 square miles (349.9 km2) is land and 7.6 square miles (19.7 km2), or 5.29%, is water. Bodies of water include the Delaware and Schuylkill Rivers, and Cobbs, Wissahickon, and Pennypack Creeks. The lowest point is sea level, while the highest point is in Chestnut Hill, at approximately 445 feet (136 m) above sea level (near the intersection of Germantown Avenue and Bethlehem Pike).

Visible to the south of the city is Delaware Bay, a major estuary outlet of the Delaware River on the Northeast seaboard of the United States whose fresh water mixes for many miles with the waters of the Atlantic Ocean. It has an area of 782 square miles. The bay is bordered by the State of New Jersey and the State of Delaware. The shores of the bay are largely composed of salt marshes and mud flats, which appear white in this image, with only small communities inhabiting the shore of the lower bay.

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January 13th, 2012 Category: Rivers, Wetlands

Mali - January 10th, 2012

The Niger River is the principal river of western Africa, extending about 4,180 km (2,600 mi), and the third longest river in all of Africa. Its drainage basin is 2,117,700 km2 (817,600 sq mi) in area. Its source is in the Guinea Highlands in southeastern Guinea. It runs in a crescent through Mali, Niger, on the border with Benin and then through Nigeria, discharging through a massive delta into the Atlantic Ocean.

This image, however, focuses the Inner Niger Delta, also known as the Macina or Niger Inland Delta, is a large area of lakes and floodplains in the semi-arid Sahel area of central Mali, just south of the Sahara desert. The delta consists of the middle course of the Niger River, between the bifurcated Niger and its tributary, the Bani, which from here run north towards the desert. As this image was captured during dry season, which lasts from October to June, not much water or plantlife can be seen.

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December 26th, 2011 Category: Deserts, Rivers, Wetlands

Mali - December 22nd, 2011

This image of Mali shows the Sahara Desert just north of the Niger River and the Inner Niger Delta (bottom center). The wetlands of the delta do not appear very large or green because the region is still experiencing the dry season.

In the upper left quadrant, an area of red desert can be observed. This is part of the Sahara in Tombouctou, the largest and northern-most region of Mali, famous for its capital, the ancient city Timbuktu. The city itself is located at the southern edge of the Sahara, near the Niger River.

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