Glencoe World GeographyChapter 20:
The Physical Geography of Africa South of the SaharaChapter Overviews
Africa south of the Sahara is roughly three times the size of the continental
United States. The northern edge of the region borders the massive Sahara. The
Atlantic and Indian Oceans surround the rest of the continent. The annual rainfall
rate for this region varies from more than 60 inches in the tropical rain forests
near the Equator to less than 4 inches in the semiarid steppe climate.
The Land Africa's overall elevation is higher than that of any other
continent. High plateaus cover the continents, rising in elevation from the
coast inland and from west to east. Volcanic mountains, such as Kilimanjaro,
are located in the Eastern Highlands. Shifting tectonic plates formed the Great
Rift Valley, which runs from Syria to Mozambique. Most of the region's lakes
are near the Great Rift Valley. The region's great rivers originate in the high
plateaus and descend toward the sea. Sharp escarpments and steeps cataracts
make navigation impossible on parts of these rivers. Africa south of the Sahara
is rich in natural resources, including oil, gold, uranium, and diamonds. Because
of irregular and unpredictable rainfall, irrigation and harnessing hydroelectric
power are difficult. Climate and Vegetation Near the Equator, orchids and ferns grow amid
the canopy of trees that tower up to 150 feet above the floor of the tropical
rain forests. Tropical grasslands, known as savanna, cover nearly half of the
continent. Tornadoes sometimes occur there when northeastern winds, called harmattans,
collide with humid air blown in from monsoons. Further north and south of the
savannas are drier steppe climates with low-growing grasses and acacia trees.
Grasses and trees can even be found in isolated deserts, such as the Kalahari
in southern Africa, where little rain falls. |