126 articles
Agulhas Current
The Agulhas Current is the strong, warm western boundary current of the southwest Indian Ocean and the Southern Hemisphere's strongest, flowing along South Africa's east coast.
Amerigo Vespucci
Amerigo Vespucci (Americo Vespucio), Florentine merchant-navigator ca. 1451–1512, recognized South America as a new continent; his voyages of 1499 and 1501–1502 underpinned Waldseemüller's 1507 map, which named America after him.
Ancylus Lake
Ancylus Lake was a freshwater lake stage in the postglacial Baltic Sea basin, following the Yoldia Sea and preceding the Littorina Sea, lasting roughly from 8800 to 6700 BC.
Andaman Islands
The Andaman Islands is a large archipelago located in the Bay of Bengal, forming the union territory of India that encompasses the Nicobar Islands.
Antarctic Circumpolar Current
The Antarctic Circumpolar Current, also known as the West Wind Drift, is the world's largest ocean current, flowing eastward around Antarctica and connecting the Atlantic, Pacific, and Indian Oceans.
Antarctic sea ice
Antarctic sea ice is frozen seawater around Antarctica, measured by satellite since November 1978 as extent (ocean at least 15% ice covered). It rose slightly until 2014, then collapsed after 2016 to record lows in 2023–2025.
Arctic dipole anomaly
The Arctic dipole anomaly, also called the Arctic Dipole, is a pattern of sea-level pressure variability in the Arctic that drives sea ice toward the Atlantic.
Arctic Ocean
The Arctic Ocean is the pole-centered, land-enclosed ocean, about 4,000 m deep and divided by the Lomonosov Ridge, covered by thin sea ice that is rapidly thinning and shrinking, with gateways at Fram Strait, Barents Sea Opening, and Bering Strait.
Arctic Ocean circulation
Arctic Ocean circulation is the system of currents and water-mass transformations moving heat and freshwater between the North Atlantic and the ice-covered Arctic basin, driven by winds, river freshwater, and warm Atlantic inflow.
Arctic sea ice
Arctic sea ice is the frozen seawater covering most of the Arctic Ocean, ranging from seasonal sheets to ridged multi-year floes that can circulate for seven to ten years.
Ascension Island
Ascension Island, in the UK Overseas Territory of St Helena, Ascension and Tristan da Cunha, is a volcanic South Atlantic island discovered in 1501, garrisoned by Britain in 1815 as HMS Ascension, with no permanent population and a 2019 EEZ-wide marine protected area.
Atlantic meridional mode
The Atlantic meridional mode (AMM) is the dominant mode of coupled ocean-atmosphere variability in the tropical Atlantic, an anomalous north-south sea surface temperature gradient across the equator.
Atlantic meridional overturning circulation
Atlantic meridional overturning circulation (AMOC): basin-scale Atlantic current system moving ~17 Sv northward and ~1.2 PW of heat, driven by Labrador and Nordic Seas deep-water formation; monitored by RAPID since 2004 and projected to weaken 18–43% by 2100.
Atlantic multidecadal oscillation
The Atlantic multidecadal oscillation (AMO), or Atlantic multidecadal variability (AMV), is a fluctuation of North Atlantic sea surface temperature on a 60–80 year time scale, linked to rainfall and hurricanes.
Atlantic Niño
The Atlantic Niño is an episodic warming of the eastern equatorial Atlantic Ocean, a smaller, shorter counterpart of Pacific El Niño that peaks in boreal summer and affects Sahel rainfall.
Atlantic Northwest Africa
Atlantic Northwest Africa is FEOW freshwater ecoregion 501, a Palearctic temperate coastal rivers unit along Morocco, Western Sahara, Mauritania, Algeria, and Spain, with Iberian faunal elements, Africa's only native salmonid, and high endemism.
Atlantic Ocean
The Atlantic Ocean is Earth's second largest ocean basin, about 106,460,000 km² (20% of Earth's surface), between the Americas and Europe-Africa, home of the AMOC and Gulf Stream.
Atlantic slave trade
Atlantic slave trade (transatlantic slave trade): forced transport of 10-12 million enslaved Africans to the Americas, 16th-19th centuries, via the triangular trade and Middle Passage; about 2 million died at sea; documented in the SlaveVoyages database.
Azores
The Azores (Açores) are a Portuguese autonomous region of nine volcanic islands in the North Atlantic Macaronesia, straddling the North America-Eurasia-Nubia triple junction, with 241,025 residents and a large tourism and conservation economy.
Baltic Ice Lake
Baltic Ice Lake, a large ice-dammed freshwater lake filling the Baltic basin during the last deglaciation, drained catastrophically about 25 m through central Sweden before the Yoldia Sea formed.
Beaufort Gyre
The Beaufort Gyre is a wind-driven anticyclonic circulation in the Arctic Ocean's Canada Basin and its largest freshwater reservoir, storing about 25% of Arctic freshwater; it gained over 6,400 km3 from 2003 to 2018 and is regulated by the ice-ocean governor.
Bermuda
Bermuda, a self-governing British Overseas Territory in the North Atlantic, is a limestone-capped volcanic seamount settled by the English in 1612, with an economy led by international business and tourism and a recent return to fiscal surplus.
Boa Vista
Boa Vista is Cabo Verde's third-largest island (620 km²), a flat desert island in the Barlavento group with dunes, Sal Rei as its town, and two-thirds of the country's loggerhead turtle nesting.
Borders of the oceans
Borders of the oceans: conventional IHO limits (S-23, 1953; S-130 digital) versus physical fronts. Atlantic–Indian at Cape Agulhas 20°E, Indian–Pacific via Tasmania 146°55'E, Southern Ocean recognized 2023 at 60°S.
Cache Creek Ocean
Cache Creek Ocean: ancient Panthalassa ocean basin preserved as the exotic Cache Creek terrane of British Columbia and Yukon, with Tethyan Permian fusuline fossils, blueschist, and Jurassic closure during Intermontane terrane amalgamation.
California Current
The California Current is a cold, equatorward eastern boundary current of the North Pacific gyre along the US West Coast, spanning nearly 3,000 km from British Columbia to Baja California; wind-driven seasonal upwelling fuels one of the world's most productive marine ecosystems.
Cape Verde
Cape Verde (Cabo Verde), ten-island Atlantic archipelago 500 km off West Africa, independent from Portugal since 1975; upper-middle-income since 2025 with a tourism-driven economy, euro-pegged escudo, and Sal and Boa Vista as main tourist islands.
Central American Seaway
Central American Seaway: Neogene Atlantic–Pacific marine passage (~200 km wide) across the Panama Arc region, closing in stages from ~12–9 Ma (deep) to ~2.76 Ma (surface), forming the Isthmus of Panama.
Chagos Archipelago
Chagos Archipelago: 58 coral islands in the central Indian Ocean, administered as the British Indian Ocean Territory from 1965; subject of the 2019 ICJ advisory opinion and the 2025 UK-Mauritius sovereignty treaty covering Diego Garcia.
Champlain Sea
Champlain Sea (mer de Champlain): cold, brackish postglacial arm of the Atlantic flooding the St. Lawrence Lowlands and Ottawa Valley about 14,000–10,500 cal yr BP, source of sensitive Leda clay, distinct from the Goldthwait Sea east of Quebec City.