(I FOUND THIS ARTICLE ON NATIONAL GEOGRAPHIC)
This climatic symmetry is disturbed, however, by Africa’s unequal shape. The continent’s narrow southern section is far more influenced by oceanic factors than the bulging northern section. Africa’s northern half is more dry and hot, while its southern end is more humid and cool.
Climatic factors greatly influence Africa’s agriculture, which is considered the continent’s single most important economic activity. Agriculture employs two-thirds of the continent’s working population and contributes 20 to 60 percent of every country’s gross domestic product (GDP). GDP is the total value of goods and services produced in a country during one year.
Important climatic regions of agriculture include tropical wet, savanna, desert, Mediterranean, and highland.
Tropical wet conditions occur along the Equator, the Gulf of Guinea, and the east Madagascar coast. Temperatures remain near 27° Celsius (80° Fahrenheit) year-round. Annual precipitation varies from 152 centimeters (60 inches) inland to 330 centimeters (130 inches) along the coasts. Important crops to Africa’s tropical wet regions include the plantain, pineapple, coffee, cocoa, and oil palms. (Oil from this palm tree is the primary cooking oil in Africa, as familiar as olive oil or corn oil in North America.)
Savanna conditions occur in much of eastern and southern Africa. Temperatures here are cooler and more variant than in tropical wet regions. Annual precipitation is between 50 and 152 centimeters (20 to 60 inches). The dry season in the savanna can last as long as six months. Important savanna crops include the cassava (related to the potato), peanuts, peppers, okra, eggplant, cucumber, and watermelon. Africa’s most important grain crops, millet and sorghum, are grown here.
Desert conditions occur in northern Africa, especially in the Sahara and the Sahel. Temperatures can range from 54° Celsius (130° F) on the hottest days to freezing on the coldest nights. Annual precipitation never exceeds 25 centimeters (10 inches), and some areas go without rain for years. Important desert crops include date palms and cotton.
Mediterranean climate conditions occur along the extreme northern and southern coasts of Africa. These regions have mild temperatures, dry summers, and moderately rainy winters. Important crops include figs, olives, oranges, tomatoes, onions, and large vegetables, such as cabbage and cauliflower.
Highland conditions occur in the highest elevations of Africa, particularly in the Ethiopian Highlands. Temperatures here are much colder than the surrounding lowlands. Precipitation depends on the orientation of the mountain in relation to moisture-bearing winds. Important highland crops include alfalfa, potatoes, and wheat.
Forestry, the management of trees and other vegetation in forests, is an important economic activity in Africa. On average, forest products account for 6 percent of Africa’s gross domestic product (GDP), more than any other continent. This is a result of Africa’s abundant forest cover, with 0.8 hectares (2 acres) per person, compared with 0.6 hectares (1.5 acres) globally. In central and western Africa, where forest cover is heaviest, the forest sector contributes more than 60 percent of GDP.
The export of forest products, especially high-grade woods like mahogany and okoume, brings in significant revenue. These woods are mostly found in the countries of the Congo Basin—Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Gabon, and Equatorial Guinea—where there is a dense rain forest. Okoume, for example, accounts for 90 percent of the trees logged in Gabon. These woods are generally exported to Japan, Israel, and the European Union. Mahogany and okoume are used to make everything from homes to musical instruments to lightweight aircraft.
Africa’s forest sector, however, suffers from illegal logging and overharvesting of certain tree species. Many species of both mahogany and okoume are endangered. Experts argue that overharvesting will eventually destroy forest habitats. Saplings planted to replace the logged trees do not grow fast enough to be harvested on a regular basis, and the rain forest habitat in which these trees thrive is being destroyed for agriculture and development.
Today, Africa is torn between developing its forests to their fullest economic potential and protecting these natural landscapes from over-development. For instance, the Central African Forests Commission regulates Africa’s forestry sector and promotes sustainable uses of the Congo Basin’s rain forest products. The commission created the Sangha Tri-National Landscape, a reserve that covers more than 1 million hectares (2.4 million acres) of rain forest in Cameroon, the Central African Republic, and the Republic of the Congo.