Namibia got its name from the Namib Desert, a coastal desert, which runs for over 1200 miles along the Atlantic Coast of southern Africa covering the entire west coast of Namibia and going as deep as 124 miles inland in parts. In total, the Namib Desert covers over 31,000 square miles of land in Namibia.
The Namib is the oldest desert in the world having had arid conditions for over 55 million years. Today, the western parts of the Namib have less than 2mm of rain per year. Even the “wettest” portions of the desert average less than 200mm (7.9 inches) annually.
The cool air of the Atlantic, mixed with warm air over the desert, frequently creates a thick fog -- the coastal regions have over 180 days of thick fog coverage per year. The strong winds that bring the fog over the desert, also create huge sand dunes in the “sand sea” which runs along the coast.
The dunes created are among the tallest in the world – some up to 1000 feet high!
I climbed 560 feet to the top of one of the dunes to watch the sunrise. It was a beautiful sight, but climbing in sand isn’t the easiest!
The temperatures in the Namib can be extreme. Along the coast, temperatures remain relatively stable, usually falling between 48-68°. Inland, however, the daytime temps can top 113° (at the same time, the sand temperature can top 160°!) and can fall below freezing during the night.
Surprisingly, the tiny amount of annual rainfall, along with the frequent fog being blown in from the Atlantic, sustains both plant and animal life in the Namib, all of which have adapted to live with very little water.
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| An Aloe Plant |
One bush called “ostrich salad” can survive up to five years with no water, lying dormant until the rains come. The flowers on this bush close up when there is no water to have as little surface area as possible to avoid any evaporation.
However, when even one small drop of water hits the plant, it unfolds each leaf until it is completely open and ready for more moisture.
The acacia tree is another desert success story. Rather than many shallow roots, this tree develops one long “tap root” which grows incredibly deep seeking water below the surface. These roots average about 150 feet, but have been found up to 220 feet below the surface! As a result, it’s not uncommon to see a completely dry landscape, with one green acacia tree right in the middle.
Even when the land looks completely barren, there are seeds lingering below the surface just waiting for the next rain to fall. We saw evidence of this in one inland area of the desert. In 2009 there was 12mm of rain. In 2010, just 2mm fell. However, in 2011, 300mm fell! In 2011, lush green grasses sprouted up all over the desert floor. Prior to last year, this area hadn’t seen green grass since 1974! When we visited in 2012, the ground was once again dry, but evidence of the unusually tall grasses remained.
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| Photo from 2010 with very little ground cover. |
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| Photo taken in 2012 with tall grasses that grew in 2011. |
Shockingly a large number of animals live in the Namib as well. Most are spiders and insects, such as this tiny fellow:
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| The Armored Cricket -- Bigger than my big toe! |
But some larger bird and mammal species have adapted to desert life as well.
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| Ostriches are Completely at Home in the Desert |
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| The oryx, the national animal of Namibia, have adapted to raise their body temperature during the hot days. |
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| These oryx are seeking shelter from the mid-day sun. |
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| Vultures feeding on an animal that didn’t make it through the hot day. |
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| Feral horses surviving on very little food and water. |
Although we did see some plants and animals, what we didn’t see many of were humans.
The Namib Desert is almost completely uninhabited by people which helps to account for the low population density in Namibia. The landscape is just a bit too barren and unforgiving for easy settlement. But it’s certainly an incredible place to visit!
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