noun, Pathology. 1. the accumulation of excessive ketones in the body, as in diabetic acidosis. Origin of ketosis. 1915-1920.
Climate zones of Africa, showing the ecological break between the hot desert climate of the Sahara Desert (red), the hot semi-arid climate of the Sahel (orange) and the tropical climate of Central and Western Africa (blue).
The Sahara is the worldâs largest hot desert and one of the harshest environments on the planet. It is third largest desert overall after Antarctica and the Arctic, which are cold deserts.At 3.6 million square miles (9.4 million square kilometers), the Sahara, which is Arabic for The Great Desert, engulfs most of North Africa.The desert covers large sections of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Western Sahara, Sudan and Tunisia.he Sahara is bordered by the Atlantic Ocean on the western edge, the Atlas Mountains and the Mediterranean Sea to the north, the Red Sea on the east, and the Sudan and the valley of the Niger River on the south.