Geographically speaking, the Gulf of Guinea is made up of the maritime area located in the western part of the African continent.
It includes eight countries bordering the Atlantic Ocean - Ghana, Togo, Benin, Nigeria, Cameroon, Equatorial Guinea, Gabon, Sao Tome and Principe; with Angola and Congo as newest comers.
In its broadest sense, the Gulf of Guinea covers a much wider political field that involves the Central African and West African sub-regions. The sub-regional organisations in the area are the Economic Community of Central African States, ECCAS and the Economic Community of West African States, ECOWAS. ECCAS has a membership of 10 States while ECOWAS has 16.
According to the Columbia Electronic Encyclopedia, the Gulf of Guinea also refers to the large open arm of the Atlantic Ocean formed by the great bend of the coast of West Africa. It extends from the western coast of Côte d'Ivoire to the Gabon Estuary and is bounded on the south by the Equator. The Bights of Benin and Biafra are located in the region. Major islands include Bioko in Equatorial Guinea (formerly Fernando Po), São Tomé and Principe.
The Encyclopedia Britannica describes the Gulf of Guinea as being part of the eastern tropical Atlantic Ocean located off the western African coast. It extends westward from Cap López near the Equator to Cape Palmas at Longitude 7° West. The intersection of the Equator and Prime Meridian (zero degrees latitude and longitude ) is in the gulf. According to the International Hydrographic Organisation, the Gulf's oceanic border is the rhumb line that runs from Cape Palmas in Liberia to Cape Lopez in Gabon.
Origin Of Name
The Gulf of Guinea derives its appellation from the former names of the coasts of Africa. The south coast of West Africa located north of the Gulf of Guinea was historically called 'Upper Guinea.' The west coast of Southern Africa located to the east was historically called 'Lower Guinea.' Guinea is still attached to the names of three countries in Africa - Guinea (Conakry), Guinea Bissau and Equatorial Guinea; as well as Papua New Guinea in Melanesia.
The modern application of Guinea to the coast dates to 1481. That year, the Portuguese built a fort, São de Mina (modern day Elmina), on the Gold Coast, and their king, John II, was permitted by the Pope (Sixtus II or Innocent VIII) to style himself Lord of Guinea; a title that survived until the recent extinction of the monarchy.
Among the many rivers that drain into the Gulf of Guinea are the Niger and Volta. The coastline includes the Bight of Benin and the Bight of Bonny. The River Niger in particular deposited organic sediments in the sea for millions of years that became crude oil. The Gulf of Guinea region, along with the River Congo Delta and Angola further south, are now regarded as one of the world's top oil and gas exploration hotspots.
Other rivers in the region are Ankroba in Ghana, Niger, Forcados, Cross River, Escravos and Nun in Nigeria, Cavalla in Guinea, Komoé in Burkina Faso, Mono in Togo, Nyong, Wouri, Sanaga and Mungo in Cameroon, Oueme in Benin, Sassandra in Côte d'Ivoire, and Tano in Ghana.
The coastline of the Gulf of Guinea forms part of the western edge of the African tectonic plate. It corresponds remarkably to the continental margin of South America that runs from Brazil to the Guianas. The coincidence between the geology and the geomorphology of these two coastlines constitutes one of the clearest confirmations of the theory of continental drift.
The continental shelf of the Gulf of Guinea is almost uniformly narrow and widens to as much as 160 km from Sierra Leone to the Bijagós Archipelago, Guinea-Bissau, and in the Bight of Biafra. The River Niger has built a great delta of less than 11,700 years. It is only there that the fit between the African and South American tectonic plates is seriously disturbed.
The only active volcano in the region is the island arc aligned with Mount Cameroon (4,070 m). The islands of this arc (Bioko, Príncipe, São Tomé and Annobón), extend 724 km offshore to the southwest. The entire northern coast of the gulf is washed by the eastward flow of the Guinea Current, which extends 400 to 480 km offshore from Senegal to the Bight of Biafra.
The gulf's tropical water is separated from the Equator-ward flow of the cool Benguela and Canary currents by sharp frontal regions off the Congo and Senegal rivers, respectively. The Benguela Current, as it swings westward, forms the South Equatorial Current to the south of, and running counter to, the Guinea Current.
The warm tropical water of the Gulf of Guinea is of relatively low salinity because of river effluents and high rainfall along the coast. This warm water is separated from deeper, more-saline, and colder water by a shallow thermocline - a layer of water between upper and lower levels that lies usually less than 30 m deep. Coastal upwelling, and hence a rich production of plant and animal life, occurs seasonally and locally off the central gulf coasts of Ghana and Côte d'Ivoire.
The variety of the marine flora and fauna of the Gulf of Guinea is limited when compared with that of the western tropical Atlantic, especially the Indo-Pacific bio-geographic realm. This relative biological poverty results from low salinity and the high turbidity of Guinea Current water, the climatic regression to cool conditions during the Miocene Epoch (that is, 23 to 5.3 million years ago). At the time, far fewer refuges for tropical species of animals and plants were available in the Atlantic than in the Indo-Pacific region.
Because most of the coast is low-lying without natural harbours and largely separated from the dry land of the interior by a belt of muddy mangrove-infested creeks and lagoons, African coastal people have usually not taken easily to seafaring on the gulf. However, some groups in Côte d'Ivoire and Ghana where the coast is less irregular and coastal fisheries are relatively productive. The Gulf of Guinea's natural resources include offshore oil reserves and deposits of hard minerals within the continental shelf.