ClimateEditThe 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; drylands and deserts comprise 60% of the entire land surface. The record for the highest temperature recorded was set in Libya in 1922 (58 °C (136 °F))
Globally, heating of the earth near the equator leads to large amounts of upward motion and convection along the monsoon trough or Intertropical convergence zone. The divergence over the near-equatorial trough leads to air rising and moving away from the equator aloft. As it moves towards the Mid-Latitudes, the air cools and sinks, which leads to subsidence near the 30th parallel of both hemispheres. This circulation is known as the Hadley cell and leads to the formation of the subtropical ridge. Many of the world's deserts are caused by these climatological high-pressure areas, including the Sahara.
The low-level easterly African jet stream is considered to play a crucial role in the southwest monsoon of Africa, and helps form the tropical waves which march across the tropical Atlantic and eastern Pacific oceans during the warm season. The jet exhibits both barotropic and baroclinic instability, which produces synoptic scale, westward propagating disturbances in the jet known as African easterly waves, or tropical waves. A small number of mesoscale storm systems embedded in these waves develop into tropical cyclones after they move from west Africa into the tropical Atlantic, mainly during August and September. When it lies south of normal during the peak months of the Atlantic hurricane season, tropical cyclone formation is suppressed
Plants and AnimalsEdit
Africa boasts perhaps the world's largest combination of density and "range of freedom" of wild animal populations and diversity, with wild populations of large carnivores (such as lions, hyenas, and cheetahs) and herbivores (such as buffalo, elephants, camels, and giraffes) ranging freely on primarily open non-private plains. It is also home to a variety of "jungle" animals including snakes and primates and aquatic life such as crocodiles and amphibians. In addition, Africa has the largest number of megafauna species, as it was least affected by the extinction of the Pleistocene megafauna.
Africa has over 3,000 protected areas, with 198 marine protected areas, 50 biosphere reserves and 80 wetlands reserves. Significant habitat destruction, increases in human population and poaching are reducing Africa's biological diversity. Human encroachment, civil unrest and the introduction of non-native species threatens biodiversity in Africa. This has been exacerbated by administrative problems, inadequate personnel and funding problems.
There are clear signs of increased networking among African organizations and states. For example, in the civil war in the Democratic Republic of the Congo (former Zaire), rather than rich, non-African countries intervening, neighboring African countries became involved since the conflict began in 1998, the estimated death toll has reached 5 million.
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 the spread of deadly diseases (notably HIV/AIDS and malaria), 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).
By most estimates, well over a thousand languages (UNESCO has estimated around two thousand) are spoken in Africa. Most are of African origin, though some are of European or Asian origin. Africa is the most multilingual continent in the world, and it is not rare for individuals to fluently speak not only multiple African languages, but one or more European ones as well.
There are four major language families indigenous to Africa.
- The Afro-Asiatic languages are a language family of about 240 languages and 285 million people widespread throughout the Horn of Africa, North Africa, the Sahel, and Southwest Asia.
- The Nilo-Saharan language family consists of more than a hundred languages spoken by 30 million people. Nilo-Saharan languages are spoken by tribes in Chad, Ethiopia, Kenya, Sudan, South Sudan, Uganda, and northern Tanzania.
- The Niger–Congo language family covers much of Sub-Saharan Africa and is probably the largest language family in the world in terms of different languages.
- The Khoisan languages number about fifty and are spoken in Southern Africa by approximately 120,000 people. Many of the Khoisan languages are endangered. The Khoi and San peoples are considered the original inhabitants of this part of Africa.
Following the end of colonialism, nearly all African countries adopted official languages that originated outside the continent, although several countries also granted legal recognition to indigenous languages (such as Swahili, Yoruba, Igbo and Hausa). In numerous countries, English and French are used for communication in the public sphere such as government, commerce, education and the media. Arabic, Portuguese, Afrikaans and Spanish are examples of languages that trace their origin to outside of Africa, and that are used by millions of Africans today, both in the public and private spheres. Italian is spoken by some in former Italian colonies in Africa. German is spoken in Namibia, as it was a former German protectorate.