104
CLAUDE J. GRENOT
Very few hot deserts are found in the world. The following are typical
of the intrinsically hot deserts: central Sahara, Libya, southern Arabia,
the desert of Lut in Iran, and also, perhaps, central Australia. However,
we can also include here the littoral deserts of Chile and Peru, the southwest African Namib, the Atlantic Sahara, and Death Valley in North
America. Thus, the warm deserts are mostly located inland and from 15°
to 45° of latitude either north or south (Dubief, 1959, 1963; Cuny, 1961;
MacGinnies et al, 1968; Planhol and Rognon, 1970; and see Logan,
1968).
Louis Emberger (1938, 1955a,b) applies the term "desertic" only to
the central Sahara, as it certainly would not be suitable for most of the
Asiatic deserts or even for the North American Great Basin Desert. As
a matter of fact, the American deserts are more representative of desertic
steppes than true deserts with the exception of Death Valley (California).
The latter is a perfect desert in miniature. Figure 1 is a map of the
Sahara.
From west to east the desertic regions of the Sahara are limited
mostly by the Ghallaman-Karêt reg, the Hank, the Majâbat-al-Koubrâ, the
Tanezrouft, the Erg Chech, the Tademait, the Aguemour, the Ténéré, and
the Libyan Desert.*
The boundless space of the Sahara, devoid of a drop of water or a sprig
of grass, is not indeed a picture of legend! One can sometimes travel for
400-500 km without seeing anything but sand, gravel, or slabs of rock.
In the Algerian Sahara, the Tanezrouft is a striking example of this
"de:ert within the desert."t
II. Physical Environment of the Sahara Desert
A. BOUNDARIES OF THE SAHARA
The Sahara is the largest desert of the world not only because of its
dimensions but also because of its degree of aridity (Nachtigal, 1879;
Schirmer, 1893; Gautier, 1908, 1925, 1928; Capot-Rey, 1951, 1953;
Verlet, 1962; Dubief, 1959, 1963). It represents almost one-quarter of
the African continent. From the north to the south it covers a distance
*The principal geographic and hydrogeologic terms relative to the Sahara can be
found in the glossary of Capot-Rey et al. (1963).
t A "Bibliographic Essay of the French Sahara and its Surroundings" by
Blaudin de Thé, containing a great number of references, was published in 1960.
CLAUDE J. GRENOT
Very few hot deserts are found in the world. The following are typical
of the intrinsically hot deserts: central Sahara, Libya, southern Arabia,
the desert of Lut in Iran, and also, perhaps, central Australia. However,
we can also include here the littoral deserts of Chile and Peru, the southwest African Namib, the Atlantic Sahara, and Death Valley in North
America. Thus, the warm deserts are mostly located inland and from 15°
to 45° of latitude either north or south (Dubief, 1959, 1963; Cuny, 1961;
MacGinnies et al, 1968; Planhol and Rognon, 1970; and see Logan,
1968).
Louis Emberger (1938, 1955a,b) applies the term "desertic" only to
the central Sahara, as it certainly would not be suitable for most of the
Asiatic deserts or even for the North American Great Basin Desert. As
a matter of fact, the American deserts are more representative of desertic
steppes than true deserts with the exception of Death Valley (California).
The latter is a perfect desert in miniature. Figure 1 is a map of the
Sahara.
From west to east the desertic regions of the Sahara are limited
mostly by the Ghallaman-Karêt reg, the Hank, the Majâbat-al-Koubrâ, the
Tanezrouft, the Erg Chech, the Tademait, the Aguemour, the Ténéré, and
the Libyan Desert.*
The boundless space of the Sahara, devoid of a drop of water or a sprig
of grass, is not indeed a picture of legend! One can sometimes travel for
400-500 km without seeing anything but sand, gravel, or slabs of rock.
In the Algerian Sahara, the Tanezrouft is a striking example of this
"de:ert within the desert."t
II. Physical Environment of the Sahara Desert
A. BOUNDARIES OF THE SAHARA
The Sahara is the largest desert of the world not only because of its
dimensions but also because of its degree of aridity (Nachtigal, 1879;
Schirmer, 1893; Gautier, 1908, 1925, 1928; Capot-Rey, 1951, 1953;
Verlet, 1962; Dubief, 1959, 1963). It represents almost one-quarter of
the African continent. From the north to the south it covers a distance
*The principal geographic and hydrogeologic terms relative to the Sahara can be
found in the glossary of Capot-Rey et al. (1963).
t A "Bibliographic Essay of the French Sahara and its Surroundings" by
Blaudin de Thé, containing a great number of references, was published in 1960.