The document discusses the possibility of irrigating the Sahara desert. The Sahara covers a large area of northern Africa and has sandy and rocky surfaces. Some science fiction works explore the idea of terraforming planets to make them habitable. Specifically, the document describes how in the 1800s botanists transformed the barren island of Ascension by transporting trees and plants from other locations, creating an artificial forest. It provides examples of terraforming the Sahara as an idea that has been discussed, with links for further information.

2. Can we irrigate the Sahara?
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SANGARE Ansoumane & MOUKOUBOULOU Adler

3. Can we irrigate the Sahara?
The Sahara (Arabic: Aṣ-Ṣaḥrā´ al-Kubrā, "The Great
Desert") is the world's second largest desert, after Antarctica.
Square : 9,400,000 square kilometers.
It covers most of Northern Africa :
Marocco Algeria Tunisia Lybia Egypt Soudan Tchad Niger Mali
Mauritania
Some of the sand dunes can reach 180 meters (590 ft) in height
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4. Can we irrigate the Sahara?
The Sahara has 20% and 80% sandy surfaces of rock surfaces
dominated sedimentary rocks.
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5. Can we irrigate the Sahara?
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6. Can we irrigate the Sahara?
It is a classic theme of science fiction , popularized
by American author Jack Williamson.
Objectives : Study of the transformation of
 natural environment of a planet
 natural satellite
 other celestial body to make it habitable by
bringing together the conditions for life -like
land.
In France the official term is ecogenesis. Since April
17, 2008 biosphérisation ecogenesis replaced.
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7. Can we irrigate the Sahara?
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8. Can we irrigate the Sahara?
The Ascension is an island of the Atlantic -South, located
between Africa and the South America , just below the equator .
It is part of British territory overseas in St. Helena, Ascension and
Tristan da Cunha . Its county seat is Georgetown
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9. Can we irrigate the Sahara?
 In 1836 , Charles Darwin visited the island of
Ascension and found that it was a barren
island, devoid of fresh water and trees.
 In 1843 , the botanist and explorer Joseph
Hooker visited the island. Four years
later, Hooker, with much encouragement from
Darwin, informed the Royal Navy with the help
of Kew Gardens , they should develop a long-
term transport of trees from London to the Isle
of 'Ascension.
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10. Can we irrigate the Sahara?
 Thus, from 1850, each year, boats
deposited an assortment of plants
from botanical gardens in
Argentina , in Europe and South
Africa .
 In the late 1870s, Norfolk pine
, eucalyptus , bamboo and banana
trees coexisted in abundance in a
lush tropical forest, but artificial in
the highest point of the
island, Green Mountain .
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11. Can we irrigate the Sahara?
David Catling (University of Washington)
has been following the travels of Charles
Darwin and investigating his association
with botanist and explorer Joseph
Hooker.
The inhabitants of the more southerly
island of St. Helena told him, no more
than a cinder, a volcanic outcropping
between Africa and South America, and
a long way from each.
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12. Can we irrigate the Sahara?
http://en.wikipedia.org/wiki/Ascension_Island
http://www.centauri-dreams.org/?p=14217
http://www.economist.com/node/17722704
http://heliophage.wordpress.com/2009/09/15/terraforming-the-
sahara/
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