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Posts tagged Okavango Swamp

Okavango Delta and Lake Ngami, Botswana – January 22nd, 2012

20.4S 22.7E

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.

Clouds Around the Okavango Swamp, Botswana

19.2S 22.7E

June 7th, 2010 Category: Rivers

Botswana - April 16th, 2010

Botswana - April 16th, 2010

The Okavango River runs southeastward for 1,000 miles (1,600 km) from central Angola to the Kalahari (desert) in northern Botswana. Here, the river spills its waters onto the Kalahari, creating a huge inland delta called the Okavango Swamp.

The marshes of the Okavango Swamp, east of the Kalahari desert in Botswana are perhaps the best example of marshes formed in an interior, closed basin that has no drainage. Other basins without outlets like that of the Great Salt Lake in Utah have accumulated too much salt for marsh growth.

Okavango River and Delta in Angola and Botswana – June 1st, 2010

19.2S 22.7E

June 1st, 2010 Category: Image of the day, Rivers

Angola and Botswana - April 28th, 2010

Angola and Botswana - April 28th, 2010

The fan-shaped dark green area in the lower right quadrant is the Okavango Delta in Botswana. The Okavango River—formerly sometimes called the Okovango—takes its name from the Okavango (Kavango) people of northern Namibia.

The Okavango River is the fourth longest river system in southern Africa, running basically southeastward for 1,000 miles (1,600 km) from central Angola, where it is known as the Kubango, to the Kalahari Desert in northern Botswana, where the river terminates in an immense inland delta known as the Okavango Swamp.

Okavango River and Delta, Botswana

March 31st, 2009 Category: Rivers

Botswana - March 23rd, 2009

Botswana - March 23rd, 2009

Parts of southern Angola (top left), southern Zambia (top right), Namibia (bottom left) and Botswana (bottom right) can be seen here.

The Okavango River runs across the image just above the middle, before emptying onto the sands of the Kalahari Desert in Botswana and creating the Okavango Delta (or Okavango Swamp).

This is the world’s largest inland delta, and an uncommon end for the Okavango River, considered unusual because it does not have an outlet to the sea.

Although the area around the delta appears quite well irrigated and green with vegetation, the true flood period will not begin for another month.

Okavango Delta, Botswana

January 16th, 2009 Category: Lakes

Okavango Delta in Botswana - November 29th, 2008

Okavango Delta in Botswana - November 29th, 2008

The Okavango Delta is created by the Okavango River, which is unusual in that it has no outlet to the sea.

Instead, it empties onto the sands of the Kalahari Desert in Botswana, irrigating 15,000 km², and thus creating the Okavango Delta (or Okavango Swamp). This is the world’s largest inland delta.

Each year some 11 cubic kilometres of water reach the delta and the nearby Moremi Wildlife Reserve. Some of this water reaches further south to create Lake Ngami.

The waters of the Okavango Delta are subject to seasonal flooding, which begins about mid-summer in the north and six months later in the south (May/June).

The water from the delta is evaporated relatively rapidly by the high temperatures, resulting in a cycle of cresting and dropping water in the south. Islands can disappear completely during the peak flood, then reappear at the end of the season.

The water entering the delta is unusually pure, due to the lack of agriculture and industry along the Okavango River.

It passes through the sand aquifers of the numerous delta islands and evaporates/transpirates by leaving enormous quantities of salt behind. These precipitation processes are so strong that the vegetation disappears in the center of the islands and thick salt crusts are formed.

In the image, we can see the delta during a period in which it appears green with vegetation and not much salt is visible. As there is little agriculture and industry along the river north of the delta, the water is not colored tan by runoff.

source Wikipedia