Kalahari Desert northwest, forming marshes that are rich in wildlife. Ancient dry riverbeds—called omuramba—traverse the central northern reaches of the Kalahari and provide standing pools of water during the rainy season. A semi-desert, with huge tracts of excellent grazing after good rains, the Kalahari supports more animals and plants than a true desert, such as the Namib Desert to the west. There are small amounts of rainfall and the summer temperature is very high. The driest areas usually receive of rain per year, and the wettest just a little over . The surrounding Kalahari Basin covers over extending further into Botswana, Namibia
Libyan Desert area of . most of which is desert save for a narrow coastal strip to the north on the shore of the Mediterranean, and the mountains of Cyrenaica (the Jebel Akhdar, or "Green Mountains"). The desert covers an area of approximately , and extends approximately 1,100 km from east to west, and 1,000 km from north to south, in about the shape of a rectangle slanting to the south-east. Like most of the Sahara, this desert is primarily sand and hamada or stony plain. Sand plains, dunes, ridges, and some depressions (basins) typify the endorheic region, with no rivers draining