May 9th, 2012 Category: Deserts, Lakes, Rivers

Egypt - May 8th, 2012

Lake Nasser, created as a result of the construction of the Aswan High Dam across the waters of the Nile between 1958 and 1971, is an important water source for Egypt (above) and Sudan (below). Visible to its west are the Toshka Lakes, filled by the overflow from Lake Nasser.

Some areas of agriculture can be seen in this extremely arid region, irrigated by Lake Nasser’s waters. Crops can be observed near the Nile in the upper right quadrant, and by the center left edge of the image. The latter are part of the New Valley Project (click link for images of how the area has grown), a system of canals built to carry water from Lake Nasser to irrigate the sandy wastes of the Western Desert of Egypt, which is part of the Sahara Desert.

Tags: Aswan High Dam Egypt Lake Nasser New Valley Project Sudan Toshka Lakes | | Leave a comment

May 7th, 2012 Category: Deserts, Image of the day, Phytoplankton

Namibia - May 6th, 2012

A faint phytoplankton bloom hangs in the waters off the shores of Namibia. The bloom is situated west of the southern part of the Namib Desert, an immense dunefield with tall, orange sand dunes. Phytoplankton blooms are common in this area due to the mixing of hot and cold ocean currents.

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May 6th, 2012 Category: Deserts, Lakes, Salt Flats

Algeria and Tunisia - April 14th, 2012

The Mediterranean coast from Morocco (left), across Algeria, to Tunisia (right) is green and vegetated, in contrast with the sands of the Sahara Desert to the south. Two large lakes can be observed amidst the desert sands, however: Chott el Djerid and Chott Ech Chergui.

The former is located in Tunisia. It is a large endorheic salt lake with a width of 20 km (12 mi) at its narrowest point, and a length of over 250 km (160 mi). Here, it appears various shades of tan, with the lighter areas likely indicating a salt crust.

Chott Ech Chergui is a large endorheic salt lake in northwestern Algeria, located at in the Saharan Atlas. The lake has an area of about 2000 km² and is one of the largest lakes in Algeria. Chott Ech Chergui is designated a Ramsar wetland of international importance.

Tags: Algeria Chott Ech Chergui Chott el Djerid Morocco Sahara Desert Tunisia | | Leave a comment

May 2nd, 2012 Category: Deserts, Lakes

Chad - April 28th, 2012

The Sahara Desert encroaches upon Lake Chad, located mainly in the far west of Chad, bordering on northeastern Nigeria, Niger and Cameroon. The name Chad is a local word meaning “large expanse of water”, in other words, a “lake”.

Lake Chad is the remnant of a former inland sea. Closer to the present, Lake Chad was first surveyed by Europeans in 1823, and it was considered to be one of the largest lakes in the world then. Lake Chad has shrunk considerably since the 1960s, when its shoreline had an elevation of about 286 metres (938 ft) above sea level, and it had an area of more than 26,000 square kilometres (10,000 sq mi), making its surface the fourth largest in Africa.

An increased demand on the lake’s water from the local population has likely accelerated its shrinkage over the past 40 years. The entire area is subject to desertification. In the upper part of the image, some dust can be seen blowing over the northwestern lobe of the lake.

Tags: Cameroon Chad Desertification Lake Chad Niger Nigeria Sahara Desert | | Leave a comment

May 1st, 2012 Category: Deserts, Image of the day

Namibia - April 15th, 2012

This image focuses on the bright red and orange sand dunes of the souther Namib Desert. The Southern Namib (between Lüderitz and the Kuiseb River) comprises a vast dune sea with some of the tallest and most spectacular dunes of the world: in the Sossusvlei area, several dunes exceed 300 meters (984 ft) in height. As one moves eastward, the dunes give way to more rocky terrain.

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April 30th, 2012 Category: Deserts

Peru - April 28th, 2012

This image focuses on Peru’s Piura Region, which has many climate variations due to its geographical location. It is just 4 degrees south of the equator, yet receives two ocean currents at the same time: the cold Humboldt Current and the warm El Niño Current. This makes the Piura Region a land that is both tropical and arid at the same time, as can be observed by the mix of desert and vegetated terrain in this image.

The coast is divided by the Peruvian subtropical desert of Sechura on the south and savanna-like scrub tropical-dry forests to the center and north of the region. There are also small valleys of tropical climate, where rice and coconut fields are common, especially around the Piura and Sullana rivers. Topography is smooth in the coast and rough in the Sierra. There are many arid plains in the southern region. The Sechura Desert, located south of the Piura River, is Peru’s largest desert and one of the world’s few examples of a tropical desert; it borders a tropical terrain to the north.

Tags: Peru Piura Region Piura River Sechura Desert Sullana River | | Leave a comment

April 26th, 2012 Category: Deserts, Phytoplankton, Salt Flats, Sediments

Libya and Tunisia - April 14th, 2012

Bright blue and green sediments and phytoplankton can be observed in the Gulf of Gabes and all along the shores of Tunisia, stretching to the Libyan coastline as well. The color is darker green in the Gulf of Gabes and around the Kerkennah Islands, and bright blue east of Djerba.

Further inland, the Chott el Djerid appears as a large, dark tan area. It is a large endorheic salt lake in southern Tunisia and the largest salt pan of the Sahara, with a surface area of over 7,000 km2. South of Chott el Djerid, the Grand Erg Oriental desert begins.

Tags: Chott el Djerid Djerba Grand Erg Oriental Gulf of Gabes Kerkennah Islands Libya Sahara Desert Tunisia | | Leave a comment

April 20th, 2012 Category: Deserts, Rivers, Volcanoes

USA - April 17th, 2012

The Rio Grande can be seen flowing down the left side of this image, in the state of New Mexico, USA. Visible to the east of the river are the White Sands National Monument, is a protected area of glistening white sands rising from the heart of the Tularosa Basin that contains the world’s largest gypsum dunefield. The dark line with thick ends north of the White Sands is the Carrizozo Malpais, a 75 kilometer long area of basaltic lava flows.

Tags: Carrizozo Malpais New Mexico Rio Grande Tularosa Basin USA White Sands National Monument | | Leave a comment

April 18th, 2012 Category: Deserts

Morocco and neighbors - April 14th, 2012

The Sahara Desert or “Great Desert” is the world’s largest hot desert; at over 9,400,000 square kilometres (3,600,000 sq mi), it covers most of Northern Africa, making it almost as large as China or the United States. This image shows the desert extending across Morocco, Western Sahara, Mali, Mauritania and Algeria. Although a large part of Morocco is mountainous, particularly due to the Atlas Mountains in the center and the south of the country, the majority of the rest of the image appears covered by Saharan sands.

Tags: Algeria Atlas Mountains Mali Mauritania Morocco Sahara Desert Western Sahara | | Leave a comment