Spread of Islam

Tropical Lands and Peoples: In order to obtain food people of Africa and Asia used old but successful methods whether they were in desert, grassland, or tropical rain forest. They also modified the environment to suit their needs with irrigation works and mining. The Tropical Environment: The tropics are warm year round Africa lies almost entirely within the tropics, as do southern Arabia, most of India, and all of the Southeast Asian mainland and islands Winds from a permanent high-pressure air mass over the South Atlantic deliver heavy rainfall to the western coast of Africa during much of the year. In December and January, large high-pressure zones over northern Africa and Arabia produce a southward movement of dry air that limits the inland penetration of the moist ocean winds.