Africa is the world's second-largest and second-most-populous continent. At about 30.2 million km² including adjacent islands, it covers six percent of the Earth's total surface area and 20.4 percent of the total land area. With 1.1 billion people as of 2013, it accounts for about 15% of the world's human population. The continent is surrounded by the Mediterranean Sea to the north, both the Suez Canal and the Red Sea along the Sinai Peninsula to the northeast, the Indian Ocean to the southeast, and the Atlantic Ocean to the west. The continent includes Madagascar and various archipelagoes. It has 54 fully recognized sovereign states ("countries"), nine territories and two de facto independent states with limited or no recognition.
Africa's population is the youngest among all the continents; 50% of Africans are 19 years old or younger.
Africa, particularly central Eastern Africa, is widely accepted as the place of origin of humans.
Algeria is Africa's largest country. The Seychelles are Africa's smallest country. Nigeria is Africa's largest country by population. The Seychelles are Africa's smallest country by population. Africa's highest point is Mt Kilimanjaro in Tanzania. Africa's lowest point is Lake Assal in Djibouti.
AFRICA GEOGRAPHY NOTES:
Two of Africa's most interesting geographical features are the Nile River System and Sahara Desert; both impressive in so many ways.
Nile River System: The Nile is a north-flowing river considered the longest river in the world at 6,650 km (4,130 mi) long. It is shared by and benefits eleven countries. The White Nile and Blue Nile are its major tributaries. The White Nile is longer and rises in the Great Lakes region of central Africa, flowing north from Tanzania to South Sudan. The Blue Nile is the source of most of the water and both rivers join near Khartoum, Sudan The northern section of the river flows almost entirely through desert, from Sudan into Egypt. The Nile ends in a large delta that empties into the Mediterranean Sea.
Sahara Desert: It's the world's hottest desert, the third largest desert after Antarctica and the Arctic, and almost as large as China. Covering almost one-third of the continent, the Sahara is the largest desert in the world at approximately 3,500,000 sq. miles (9,065,000 sq. km) in total size. Topography includes areas of rock-strewn plains, rolling sand dunes and numerous sand seas. It ranges in elevation from 100 ft. below sea level, to peaks in the Ahaggar and Tibesti Mountains, that exceed 11,000 ft. (3,350m). Regional deserts include the Libyan, Nubian and the Western desert of Egypt, just to the west of the Nile. Almost completely without rainfall, a few underground rivers flow from the Atlas Mountains, helping to irrigate isolated oases. In the east, the waters of the Nile help fertilize smaller parts of the landscape.
Africa is the largest of the three great southward projections from the largest landmass of the Earth. Separated from Europe by the Mediterranean Sea, it is joined to Asia at its northeast extremity by the Isthmus of Suez.
From the most northerly point to the most southerly point is a distance of approximately 8,000 km; from the westernmost point to the most easterly projection is a distance of approximately 7,400 km. The coastline is 26,000 km long.
Geologically, Africa includes the Arabian Peninsula; the Zagros Mountains of Iran and the Anatolian Plateau of Turkey mark where the African Plate collided with Eurasia. The Afrotropic ecozone and the Saharo-Arabian desert to its north unite the region biogeographically, and the Afro-Asiatic language family unites the north linguistically.
The climate of Africa ranges from tropical to subarctic on its highest peaks. Its northern half is primarily desert, or arid, while its central and southern areas contain both savanna plains and very dense jungle (rainforest) regions. In between, there is a convergence, where vegetation patterns such as sahel and steppe dominate. Africa is the hottest continent on earth and 60% of the entire land surface consists of drylands and deserts. The record for the highest-ever recorded temperature, in Libya in 1922, was discredited in 2013.
Although it has abundant natural resources, Africa remains the world's poorest and most underdeveloped continent, the result of a variety of causes that may include corrupt governments that have often committed serious human rights violations, failed central planning, high levels of illiteracy, lack of access to foreign capital, and frequent tribal and military conflict (ranging from guerrilla warfare to genocide). According to the United Nations' Human Development Report in 2003, the bottom 25 ranked nations (151st to 175th) were all African.
Poverty, illiteracy, malnutrition and inadequate water supply and sanitation, as well as poor health, affect a large proportion of the people who reside in the African continent.
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