The Sahara Was Once Green

Introduction & Top Questions References & Edit History

Images

Photo of a small tree-lined lake surrounded by sand.

Two side-by-side maps of Africa show the seasonal path of the African monsoon. Arrows indicate wind systems, including the northeast trade winds and the hot, dry Harmattan winds. Shaded bands in varying greens represent rainfall amounts, with the Intertropical Convergence Zone shifting northward and rainfall bands reaching farther into West Africa from June to September, and moving southward with rainfall concentrated in central and southern Africa from January to March.

The Sahara Was Once Green: Media

Images

Photo of a small tree-lined lake surrounded by sand.

Umm al-Ma Lake, an oasis in the Awbari Sand Sea in Libya

An oasis, a fertile tract of land within a desert, springs from the middle of the...

© Patrick Poendl/Shutterstock.com

Two side-by-side maps of Africa show the seasonal path of the African monsoon. Arrows indicate wind systems, including the northeast trade winds and the hot, dry Harmattan winds. Shaded bands in varying greens represent rainfall amounts, with the Intertropical Convergence Zone shifting northward and rainfall bands reaching farther into West Africa from June to September, and moving southward with rainfall concentrated in central and southern Africa from January to March.

Wind and rainfall patterns of the West African monsoon

During the summer monsoon, rains advance as far as the southern Sahara. However,...

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