Atlantic Ocean basin

Atlantic Ocean basin
Name	Atlantic Ocean basin
Caption	Bathymetry of the Atlantic Ocean basin
Location	Between the Americas, Europe, Africa, and Antarctica
Area	~106,460,000 km2
Max-depth	~8,486 m
Countries	United States, Brazil, United Kingdom, Spain, Portugal, France, Canada, Argentina, South Africa, Norway, Iceland, Morocco, Nigeria, Ghana, Cuba, Mexico, Venezuela

Atlantic Ocean basin The Atlantic Ocean basin is the vast marine basin separating the Americas from Europe and Africa, extending southward to Antarctica. It hosts major oceanic features such as mid-ocean ridges, abyssal plains, and continental shelves, and links with the Arctic Ocean and Southern Ocean via strategic straits and passages. Historically central to exploration, trade, and strategic naval operations, it remains crucial for contemporary maritime law implementation, transoceanic cables, and global climate regulation.

Geography and boundaries

The basin is bounded by continental margins of the United States and Canada in the west, the coasts of Europe including United Kingdom and Portugal in the northeast, and the western shores of Africa and South America in the east and southwest, with the southern limit near South Georgia and the South Sandwich Islands adjacent to Antarctica. Prominent marginal seas include the Caribbean Sea, Gulf of Mexico, Mediterranean Sea—connected via the Strait of Gibraltar—and the Bay of Biscay, while the Rockall Trough and Sargasso Sea are notable internal features. Major islands and archipelagos include Greenland, Iceland, Bermuda, the Azores, and the Canary Islands, and key passages such as the Davis Strait, Yucatán Channel, and Florida Straits define shipping routes and biogeographic boundaries.

Geology and tectonics

The basin is dominated by the Mid-Atlantic Ridge, a spreading center formed by plate divergence between the North American Plate, South American Plate, Eurasian Plate, and African Plate. Its formation followed the breakup of Pangaea during the Mesozoic and the opening tied to seafloor spreading documented by magnetic anomalies first analyzed by researchers associated with institutions like the Scripps Institution of Oceanography. Transform faults such as the Azores–Gibraltar Transform Fault and fracture zones create bathymetric complexity, while continental slumping and turbidite systems occur along margins near the Amazon Basin, Mississippi River Delta, and Niger Delta. Volcanic activity at hotspots beneath the basin formed the Iceland volcanic province and the Cape Verde islands, with hydrothermal circulation at ridge axes fostering chemosynthetic communities analogous to those studied near the Galápagos Rift.

Oceanography and circulation

The basin’s circulation is governed by the Atlantic Meridional Overturning Circulation (AMOC), which connects surface currents like the Gulf Stream and North Atlantic Current to deep return flows including the Labrador Current and Antarctic Bottom Water inflows. Wind-driven gyres—such as the North Atlantic Subtropical Gyre and South Atlantic Gyre—interact with Ekman transport and thermohaline gradients influenced by salinity inputs from the Amazon River, Congo River, and Mississippi River. Seasonal and interannual variability is linked to climatic modes including North Atlantic Oscillation and teleconnections with the El Niño–Southern Oscillation via atmospheric bridges studied by groups like the National Oceanic and Atmospheric Administration. Surface productive zones include upwelling regions off Benguela Current and Morocco coastlines, while the Sargasso Sea is notable for its floating Sargassum and oligotrophic waters.

Climate and weather systems

The basin influences and is influenced by cyclogenesis that produces Atlantic hurricane season events originating in the Caribbean Sea and eastern Atlantic Ocean waves, with tracking and forecasting conducted by National Hurricane Center and regional agencies in Cuba and Bahamas. Mid-latitude storm tracks impinging on Europe are modulated by the North Atlantic Oscillation, affecting precipitation regimes in United Kingdom and Scandinavia. Sea-surface temperature anomalies play roles in decadal variability documented in paleoclimate proxies from the Gulf Stream and sediment cores recovered by programs like the Integrated Ocean Drilling Program. Extreme events include historical storms such as the Great Hurricane of 1780 and modern impacts on ports like New Orleans.

Marine biodiversity and ecosystems

The basin supports ecosystems from continental shelf fisheries off New England and Norway to benthic communities on abyssal plains and hydrothermal vents along the Mid-Atlantic Ridge. Productive upwelling systems such as the Benguela Current and Canary Current support fisheries for sardine and anchovy exploited by fleets from Spain and Portugal. Iconic megafauna include populations of North Atlantic right whale in the western basin, migratory routes of Atlantic bluefin tuna, and breeding colonies of seabirds on Iceland and Falkland Islands. Coral assemblages—both shallow reef taxa in the Caribbean Sea and deep-sea cold-water corals on seamounts like the Porcupine Bank—are under pressure from ocean warming, acidification, and bottom trawling monitored by bodies such as the International Council for the Exploration of the Sea.

Human use and history

Human interaction with the basin includes prehistoric coastal settlements, the age of exploration initiated by expeditions from Portugal and Spain, and the transatlantic trade routes linking ports in Lisbon, London, Liverpool, Lisbon, Rio de Janeiro, and New York City. Strategic naval engagements such as the Battle of the Atlantic during World War II shaped maritime doctrines and convoy systems. Modern uses encompass transoceanic telecommunications managed by companies like SubCom, offshore petroleum extraction on margins off Gulf of Mexico and Brazil operated by firms including Shell and Petrobras, and renewable-energy projects like offshore wind farms in waters near United Kingdom and Denmark. Governance involves multinational frameworks exemplified by the United Nations Convention on the Law of the Sea and regional fisheries management organizations including the Northwest Atlantic Fisheries Organization.

Category:Ocean basins