1. Physical Geography of Africa South of the Sahara
Chapter 20
Physical Geography of Africa South of the Sahara

2. 1. The Land
Known for extraordinary physical geography
Very diverse

3. Landforms
MI: Africa south of Sahara is a region of plateaus, mountains and rift valley in east
Massive region covers 9.5 million square miles

4. The Great Rift Valley
Runs from Syria in SWA to Mozambique in SE Africa
Rift valley – large depression in Earth’s surface, formed by tectonic plate movement
Volcanic mountains at it’s edges, deep lakes
Includes Mt. Kilimanjaro, one of largest mtns. in world
Lake Tanganyika, one of deepest and longest freshwater lakes in world, lies on western branch of GRV
Lake Malawi, more than 2300 ft deep

5. Mountains and Plateaus
Series of plateaus, rise in elevation from coast inland
Plateaus range in elevation from 500 ft to 8000 ft
Edges lined by escarpments, steep jagged cliffs, and cataracts, or waterfalls
Largest mountains include Kilimanjaro and Mt. Kenya

6. Water Systems
MI: Landforms and physical processes have influenced the regions water systems (lakes, waterfalls, rivers)
Lakes/rivers, located in basins, formed by tectonic activity
Rivers start at high elevations, make their way to the sea

7. Land of Lakes Most lakes near Great Rift Valley, E Africa
Lake Victoria, largest freshwater lake in Africa, second largest in world behind Lake Superior
Lake Chad, W. Africa, shrinking due to irrigation, desertification, global warming
Desertification – long periods of drought and land use destroy vegetation

8. Human Made Lake
Lake Volta, W. Africa (Ghana), among largest HM lake in the world
Created in 1960’s by damming Volta River
Dam built for hydroelectric power in Ghana

9. River Basins Niger River, main river in W. Africa 2600 miles long
Important for agriculture and transportation in region
Forms Niger Delta upon entering Atlantic Ocean, 200 miles wide
Delta – a triangular section of land formed by sand and silt carried downriver

10. River Basins Zambezi River, S. Central Africa 2200 miles long
Headwater near the Zambia-Angola border, flows to Indian Ocean
At border of Zambia and Zimbabwe, Zambezi falls 355 feet, forming Victoria Falls

11. River Basins Congo River, Central Africa About 2,900 miles long
Reaches sea through an estuary, or passage where freshwater meets seawater

12. Natural Resources
MI: Mineral resources and water are among the region’s most abundant natural resources
Oil – Nigeria, Angola, Gabon, Congo and Cameroon
4 percent of world oil in Sub-Saharan Africa
South Africa – half of worlds gold
Uranium – South Africa, Botswana
Water is abundant, but irregular and unpredictable, difficult to control for irrigation and hydroelectric power

13. 2. Climate and Vegetation
MI: Rain helps determine:
climate
vegetation growth

14. Tropical Climates Causes of variation in climate and vegetation:
rainfall
ocean currents
prevailing winds
elevation
latitude

15. Tropical Wet Map of p. 516 TW Zone located near equator
More than 60 inches of rain per year
Produces variety of vegetation
Rainforest levels:
Low: ferns, moss, shrubs
Mid: Trees, palms
Canopy: leafy trees, max height of 150 ft
Soil not fertile
Heavy rains leach, or dissolve and carry away, nutrients from soil
Crops grown: bananas, pineapples, cocoa, tea, coffee, timber, cotton

16. Tropical Dry
Savanna, or grassland with scattered trees, covers half of Africa
Alternating wet and dry seasons
35-45 inches annual rainfall
Hot, dry air from Sahara, called harmattan, affects TDZone
Cool, humid air from SW affect TDZone
Combination at times forms tornadoes
Animals: zebras, gazelles, hyenas, lions, giraffes and cheetahs

17. Dry Climates
MI: Dry climates of Sub-Saharan Africa located in the north and south, away from the equator

18. Steppe Transition zone between tropical dry savanna and desert
Northern steppe called the Sahel, from Senegal to Sudan
4-8 inches annual rainfall

19. Desertification Sahel, undergone desertification over past 50 years
May be caused by climate change
May be caused by human activities, animal grazing, logging, farming, etc.

20. Desert Namib Desert, Atlantic coast of Namibia
Kalahari, eastern Namibia, Botswana and part of South Africa
Daily temps in Kalahari vary widely, from 50 dg., night, to 120 dg., day

21. Midlatitude Coastal areas of South Africa, humid subtropical climates
Highland East Africa, moderate climates, adequate rainfall for farming, some snow at high elevations