Earth Snapshot RSS Feed Twitter

Archive for November 12th, 2009

Thick Outflow of Sediments from Yangtze and Han Rivers

38.9N 120.0E

November 12th, 2009 Category: Rivers

China and South Korea - October 21st, 2009

China and South Korea - October 21st, 2009

Sediments line the northeast coast of China and the west coast of the Korean Peninsula, clouding the waters of the Bohai Sea (upper left quadrant) and framing the Shandong Peninsula.

In China, the greatest outflow is coming from the Yangtze River. These sediments spill into the East China Sea near Shanghai on the Yangtze River Delta, appearing concentrated and brown near the coast and spreading outwards in a still thick, greenish plume.

Across the sea by Korea, the discharge of sediments is strongest from the Han River in South Korea. The Han is a major river, formed by the confluence of the Namhan River (South Han River) and the Bukhan River (North Han River). The Han flows through Seoul and then merges with the Imjin River shortly before it flows into the Yellow Sea.

Salar de Arizona on the Andean High Plateau, Argentina

24.7S 67.7W

November 12th, 2009 Category: Volcanoes

Argentina - September 29th, 2009

Argentina - September 29th, 2009

The Central Andean dry puna is an ecoregion located in the Andean High plateau, in South America. It is a part of the Puna grassland, occupying the southwestern portion of the Altiplano, and is located east of the Atacama Desert.

Salt Flats, locally known as Salares, are a characteristic feature of this ecoregion. Among the largest of these is the Salar de Arizaro, visible as a large, flat light grey area in this orthorectified image.

It is the largest salar of Puna, Argentina, with a surface area of 1500 km2, and the third largest salar in the Andes, after the Salar de Uyuni in Bolivia and the Salar de Atacama in Chile. The salar is used for metallic and non-metallic mining, as is it rich in salt, iron, marble, onyx and copper.

Also visible in the upper left corner, near the salar, is the Aracar Volcano. It is a large conical stratovolcano in northwestern Argentina, just east of the Chilean border. It has an uneroded summit crater about 1.5 km in diameter which contains a small crater lake.

It is located on the edge of the Puna de Atacama, a high desert plateau east of the Atacama Desert. The only observed volcanic activity was a possible steam or ash plume on March 28, 1993, seen from the village of Tolar Grande about 50 km southeast of the volcano.

Mauritania’s Coastal Zone and Ras Nouadhibou Peninsula

20.9N 17W

November 12th, 2009 Category: Snapshots

Mauritania - October 4th, 2009

Mauritania - October 4th, 2009

The Coastal Zone, or Sub-Canarian Zone, extends the length of Mauritania’s approximately 754-kilometer-long Atlantic shoreline. Prevailing oceanic trade winds from the Canary Islands modify the influence of the harmattan, producing a humid but temperate climate.

Rainfall here is minimal; in Nouadhibou it averages less than three centimeters annually and occurs between July and September. Battering surf and shifting sand banks characterize the entire length of the shoreline. Here, some dust can be seen blowing southwest off the coast.

One interesting feature of the coastline, visible near the center, is the Ras Nouadhibou (formerly Cap Blanc) peninsula. It forms Dakhlet Nouadhibou (formerly Lévrier Bay) to the east, and is fifty kilometers long and up to thirteen kilometers wide.

The peninsula is administratively divided between Western Sahara (north) and Mauritania (south), with the Mauritanian port and railhead of Nouadhibou located on the eastern shore. Dakhlet Nouadhibou, one of the largest natural harbors on the west coast of Africa, is fortythree kilometers long and thirty-two kilometers wide at its broadest point.

Mongolia’s Great Lakes Depression – November 12th, 2009

46.0N 105.0E

November 12th, 2009 Category: Image of the day, Lakes, Rivers

Mongolia - October 7th, 2009

Mongolia - October 7th, 2009

The lakes visible here in the Khyargas District of Mongolia’s Uvs Province are part of the same system interconnected lakes in the Great Lakes Depression.

The large, dark greenish blue lake at the top is Lake Khyargas, upon which the Khyargas Nuur National Park is based.  This protected area was established in 2000 and covers about 3,328 km². It also includes the smaller, lighter green, freshwater Lake Airag, just south of Lake Khyargas.

In the lower left quadrant is Lake Khar-Us. Its area value of 1,852 km² includes the island Agbash (or Ak-Bashi, White Head) with an area of 274 km², so the water surface area is 1,578 km² only. Here, the island appears to almost separate the bright green western side of the lake from the brown right side. Primary inflow is the Khovd Gol river, which creates a large fan-shaped river delta on the western shores.

Finally, in the lower right quadrant are Lakes Khar and Dörgön. The waters of Lake Khar, above, appear green, while those of Lake Dörgön, below, appear dark blue.