The Namib desert is one of driest lands on
planet earth. It receives an average of 11mm rains annually! Compare that with Blantyre (in Malawi) 1500mm, Johannesburg (in RSA) 700mm and Mawsynram (in India) 11, 872mm! Over a million years of geological
activities has created sand dunes that baffle the imagination. The Namib has
some of the highest sand dunes in the world with a number of them going over 300m in hieght. These majestic and expansive dunes have
created a unique landscape that really takes the breath away from any first
time visitor.
The Sand Dunes of the Namib Desert rising to touch the
clouds
The dunes of the desert rise from the
Atlantic oceans on one edge. The meeting point of the ocean and the desert is
so breath taking a view. The rising sand mountain always makes one ask why the
sand is not collapsing into the ocean? But the sand mountain defies that logical
questions and stands majestically like a model on a Milan fashion show! Geologists and geotechnical engineers have spent years trying to explain this very point!
The Namib desert meets the Atlantic Ocean
The one prevailing feature of the Namib is
the angular position of the dunes. Everywhere one looks at the dunes one gets
an impression of movement of the dunes. This scenario is given by the distinct
waves that form on top (of the dunes). This impression is not very far from the
truth; geologist say that the dunes are constantly in motion as are they under the
effect of a constant ‘push’. The winds blowing over the Atlantic Ocean are so
strong and they are constantly pushing the sand inland. The waves on top of the dunes
point in the prevailing direction of the winds.
The dunes with waves on top
Overtime the dominance of winds in a
specific direction leads to the waves growing into dunes. Year upon year more
sand will be piled up on top of the older sand. The continued piling of the
sand creates dunes with sands that are densely compacted on the windward
side and loosely placed on the leeward
side of the dunes.
Top view of Dunne 5
General View of a Namib desert landscape