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Africa - Modern-day Climatic And Environmental Factors

volcano earth continent lava

Africa, like other continents, has been subjected to gyrating swings in climate during the Quartenary period of the last 2 million years. These climatic changes have had dramatic affects on landforms and vegetation. Some of these cyclical changes may have been driven by cosmic or astronomical phenomena including asteroid and comet collisions.

But the impact of humankind upon the African environment has been radical and undeniable. Beginning 2,000 years ago and accelerating to our present day, African woodland belts have been deforested. Such environmental degradation has been exacerbated by over-grazing, agricultural abuse, and man-made climatic change, including possible global warming caused by the buildup of man-made carbon dioxide, chlorofluorocarbons (CFCs) and other greenhouse gases.


Deforestation, desertification, and soil erosion pose threats to Africa's man-made lakes and thereby Africa's hydroelectric capacity. Africa's multiplying and undernourished populations exert ever greater demands on irrigated agriculture but the continent's water resources are increasingly taxed beyond their limits. To stabilize Africa's ecology and safeguard its resources and mineral wealth, many earth scientists say greater use must be made of sustainable agricultural and pastoral practices. Progress in environmental and resource management, as well as population control is also vital.

Resources

Books

Hancock P. L. and Skinner B. J., eds. The Oxford Companion to the Earth. Oxford: Oxford University Press, 2000.

Petters, Sunday W. Lecture Notes in Earth Sciences Series. Vol 40, Regional Geology of Africa. New York: Springer-Verlag New York, Inc., 1991.


Periodicals

Leroux, M. "The Meteorology And Climate Of Tropical Africa." Journal of Meteorology 27, no. 271 (2002): 274.


Robert Cohen

KEY TERMS

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Composite volcano

—A large, steep-sided volcano made of alternating sequences of lava and pyroclastic debris. Sometimes called a stratovolcano.

Craton

—A piece of a continent that has remained intact since Earth's earliest history, and which functions as a foundation, or basement, for more recent pieces of a continent.

Gondwanaland

—An ancestral supercontinent that broke into the present continents of Africa, South America, Antarctica, and Australia as well as the Indian subcontinent.

Graben

—A block of land that has dropped down between the two sides of a fault to form a deep valley.

Lava domes

—Small dome-shaped masses of volcanic rock formed in the vent of a volcano.

Paleoclimatologist

—A geologist who studies climates of the earth's geologic past.

Swells

—Rock strata warped upward by heat and pressure.

Volcanic neck

—A usually tall, steep mountain of lava rock that solidified in the volcano's throat, stopping up the volcano as it became extinct.

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