877 articles
General Bathymetric Chart of the Oceans
The General Bathymetric Chart of the Oceans (GEBCO) is an international program producing free maps of the world's ocean floor, run jointly by the IHO and UNESCO's IOC.
Geographe Bay
Geographe Bay is a north-facing bay in southwest Western Australia, named by Baudin's 1801 expedition. It has 50 km of arcuate sandy beach, temperate WA's most extensive seagrass meadows, and lies in the Ngari Capes Marine Park.
George VI Sound (landform)
George VI Sound: flooded block-faulted rift valley between Alexander Island and Palmer Land, Antarctic Peninsula, covered by George VI Ice Shelf; over 800 m deep, filled with warm Circumpolar Deep Water, discovered 1935 by Ellsworth.
Gerlache Strait
Gerlache Strait, also known as Belgica Strait, is a channel about 200 km long separating the Antarctic Peninsula from the Palmer Archipelago, first charted by the Belgian Antarctic Expedition in 1898.
German auxiliary cruiser Atlantis
German auxiliary cruiser Atlantis (HSK 2, Schiff 16, Raider-C), ex-cargo ship Goldenfels commanded by Bernhard Rogge; sank or captured 22 ships of 145,697 tons in 622 days before being sunk by HMS Devonshire in 1941.
Gibson Bay
Gibson Bay, Antarctica: a bay at 63°19'S 55°52'W near Joinville Island on the Antarctic Peninsula's Weddell Sea side, a UK-approved name listed in the Australian and U.S. Antarctic gazetteers; distinct from Gibson Bay, Nunavut.
Gilbert Strait
Gilbert Strait, also called Davies Gilbert Strait or estrecho Gilbert, is an Antarctic strait between Trinity and Tower Islands in the Palmer Archipelago at 63°38'S 60°16'W, named in 1828-31 for Royal Society president Davies Gilbert.
Giovanni da Verrazzano
Giovanni da Verrazzano (Janus Verrazanus, 1485-1528), Florentine navigator for Francis I of France, explored the Atlantic coast from South Carolina to Nova Scotia in 1524 aboard the Dauphine, first European to describe New York Harbor; died 1528 on a second voyage.
Gironde estuary
Gironde estuary (estuaire de la Gironde): macrotidal estuary in southwest France formed by the Garonne and Dordogne at Bec d'Ambès; largest in France, ~76 km long, 4.5 m tidal range at mouth, permanent turbidity maximum of 1-10 g/L, major migratory fish habitat.
GIUK gap
The GIUK gap, or Greenland-Iceland-UK Gap, is the North Atlantic passage between Greenland, Iceland, and the United Kingdom through which ships and submarines from Arctic waters enter the Atlantic.
Glass Beach (Fort Bragg, California)
Glass Beach at Fort Bragg, Mendocino County, California: a shore of wave-smoothed sea glass formed from town refuse dumped over bluffs from 1906 to 1967; its main cove lies in MacKerricher State Park, where collecting is prohibited and the glass has visibly thinned.
Glyfada (Γλυφάδα)
Glyfada (Γλυφάδα) is a seaside municipality of the Athenian Riviera on the Saronic Gulf, south of Athens, on the site of the ancient deme of Aixone; renamed in the early 20th century for brackish wells, with four marinas and free beaches.
Golden Gate
The Golden Gate is the roughly 3-mile-long, 1-mile-wide strait linking San Francisco Bay to the Pacific Ocean, named Chrysopylae by John C. Fremont in 1846 after the Golden Horn, with tidal currents of 4.5 to 7.5 knots.
Golden Horn
The Golden Horn (Haliç) is Istanbul's horn-shaped estuary of the Bosphorus, the historic harbor of Byzantium and Constantinople, chained against attack and bypassed by Mehmed II in 1453, later heavily polluted and restored from the 1980s onward.
Goldsmith Channel
Goldsmith Channel: two official channels in Nunavut, Canada; the main one is a roughly 100 km Arctic strait separating Stefansson Island from Victoria Island's Storkerson Peninsula, connecting Viscount Melville Sound and M'Clintock Channel, named for John Goldsmith in 1952.
Golfe du Morbihan (Kerguelen)
The Golfe du Morbihan is a large, almost fully enclosed natural harbor on the east side of the Kerguelen Islands, sheltering the French research station Port-aux-Français.
Golfo di Trieste - Italy
Golfo di Trieste (Gulf of Trieste), a shallow ~500 km2 semi-enclosed bay at the northeastern Adriatic between Italy and Slovenia; LTER site C1 since 1986, Miramare MPA, OGS marine observatory, Isonzo inflow and bora winds.
Golfo di Venezia - Italy
Golfo di Venezia (Gulf of Venice), inlet of the northwestern Adriatic from the Po Delta to Capo Promontore and an LTER-Italy site (IT12-001-M) run by CNR-ISMAR, with observations since the late 19th century and the Acqua Alta platform 15 km offshore Venice.
Golfo San Jorge
Golfo San Jorge is a large semi-open gulf of the Argentine Sea on Patagonia's central coast, spanning Chubut and Santa Cruz provinces and covering about 40,000 km².
Goodwin Sands
Goodwin Sands: shifting sandbanks 4 miles off east Kent, 10 miles long, near Dover Strait shipping lanes; about 2,000 shipwrecks, a 277 km2 Marine Conservation Zone, and a contested 2018 dredging licence.
Gotland Basin
Gotland Basin: deep sub-basin of the central Baltic Sea east of Gotland island, containing the Gotland Deep (about 249 m, station BY15); known for anoxic, hydrogen sulfide-rich deep water, episodic Major Baltic Inflow ventilation, and high internal nutrient release.
Gough Island
Gough Island (Diego Alvarez), a 91 km² volcanic island in the South Atlantic belonging to Tristan da Cunha, is a UNESCO World Heritage seabird sanctuary with a South African weather station since 1956, threatened by predatory introduced house mice.
Grand Banks of Newfoundland
Grand Banks of Newfoundland: submerged plateaus southeast of Newfoundland, also called the Grand Bank group, among the world's richest fishing grounds. Fished since Cabot's 1497 report; cod moratorium 1992; Northern cod declared healthy in 2026.
Grand Canal (Venice)
The Grand Canal, or Canal Grande, is the main waterway of Venice, Italy, crossing the city in a large "S" for about 3,800 meters and crossed by 4 bridges.
Grandidier Channel
Grandidier Channel, a channel off the Graham Coast of the Antarctic Peninsula between the Biscoe Islands and the mainland, charted by Charcot's 1903-05 French expedition and named for Alfred Grandidier.
Great Australian Bight
The Great Australian Bight is a large open bay on Australia's southern coast, spanning Western Australia and South Australia. Known for its cool-water carbonate ramp, southern right whale calving at Head of Bight, high endemism, and the 45,822 km² Great Australian Bight Marine Park.
Great Belt
The Great Belt (Storebælt) is the widest Danish strait, separating Zealand and Funen and connecting the Kattegat with the Baltic Sea, crossed by a fixed road and rail link.
Great Blue Hole
The Great Blue Hole is a 320 m wide, 125 m deep flooded karst sinkhole in Lighthouse Reef atoll, Belize, formed during glacial low sea level, anoxic below 90 m, a UNESCO-protected diving site and annually layered climate archive.
Great Pacific garbage patch
The Great Pacific garbage patch (Pacific trash vortex) is a North Pacific accumulation of floating plastic between Hawaii and California, held by the North Pacific Subtropical Gyre; estimated at 1.8 trillion pieces, mostly microplastics by count and fishing nets by mass.
Great Sandy Strait
Great Sandy Strait: 70 km double-ended sand passage estuary in south-eastern Queensland between the mainland and K'gari (Fraser Island); Ramsar site since 14 June 1999, 93,160 ha, famed for migratory shorebirds, dugongs, and turtles.