877 articles
Celebes Sea
The Celebes Sea, or Sulawesi Sea, is a semi-enclosed Pacific marginal sea between Borneo, Sulawesi, and the southern Philippines, over 290,000 km² in area, floored by Eocene oceanic crust, and crossed by the Indonesian Throughflow.
Celtic Sea
The Celtic Sea, also called Mer celtique, is an arm of the northeast Atlantic south of Ireland and southwest of Wales and Cornwall, a productive shelf sea known for major fisheries.
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.
Central Indian Ridge
Central Indian Ridge (CIR): slow to intermediate spreading mid-ocean ridge, ~2,000 km from 3°N to 25°S in the Indian Ocean, ending at the Rodrigues Triple Junction; hosts Kairei, Edmond, Dodo, and Solitaire hydrothermal vent fields.
Central New Zealand
Central New Zealand is a Marine Ecoregion of the World (MEOW) unit, MRGID 21948, defined by Spalding et al. 2007, in the Southern New Zealand marine province around Cook Strait; only 0.4 percent of it is protected.
Ceram Sea
Ceram Sea (Seram Sea, Laut Seram), a small Pacific sea in eastern Indonesia between Seram, Buru, and New Guinea's Bird's Head; IHO-defined, about 161,489 km², monsoon-driven, within the Coral Triangle.
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.
Challenger Deep
Challenger Deep, the deepest known point of the ocean, lies at the southern end of the Mariana Trench in the western Pacific, about 300 km southwest of Guam; about 10,935 m deep, named for HMS Challenger.
Challenger Plateau
Challenger Plateau, a flat undersea plateau west of New Zealand near the Lord Howe Rise, a GEBCO gazetteer feature with an orange roughy fishery, annual trawl surveys since 1983, and studied benthic ecology.
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.
Channels of the Hawaiian Islands
Channels of the Hawaiian Islands (Nā Kai ʻEwalu, the eight seas): named passages between the main islands, from Kaulakahi to ʻAlenuihāhā, with Hawaiian names, meanings, oceanography, cultural role, and modern crossings.
Charcot Bay
Charcot Bay is a bay between Cape Kater and Cape Kjellman on the Davis Coast of Graham Land, Antarctica, charted in 1902 by Nordenskjöld's Swedish expedition and named for French explorer Jean-Baptiste Charcot; a second, smaller Charcot Bay lies in Victoria Land.
Charlie-Gibbs Fracture Zone
The Charlie-Gibbs Fracture Zone is a major fracture zone in the North Atlantic Ocean that offsets the Mid-Atlantic Ridge by roughly 350 km along two parallel transform faults.
Charlotte Bay
Charlotte Bay is a bay on the Danco Coast of Graham Land, Antarctic Peninsula, charted by the Belgian Antarctic Expedition in 1898 and named for Georges Lecointe's fiancée.
Chaunskaya Bay
Chaunskaya Bay (Chaun Bay, Чаунская губа), Arctic bay in the East Siberian Sea, Chukotka, Russia; 140 km long, shallow, near Pevek; hosts a warm-water 'Arctic oasis' ecosystem sustained by hydrothermal submarine groundwater discharge.
Chesapeake Bay
Chesapeake Bay: largest estuary in the United States, a drowned river valley formed about 18,000 years ago; 64,000-square-mile watershed across six states and DC, over 17 million residents, summer dead zones, and a decades-long EPA-coordinated restoration effort.
Chile Ridge
Chile Ridge (Chile Rise), the Nazca–Antarctic spreading center in the southeast Pacific, subducts beneath South America at the Chile Triple Junction near 46°S, migrating northward over 14 million years.
Chukchi Plateau
Chukchi Plateau (Chukchi Cap): submerged continental-crust plateau in the western Arctic Ocean, western part of the Chukchi Borderland, rising from ~3,800 m Canada Basin depths to ~350 m, with 28–29 km crust and glacially scoured seafloor.
Chukchi Sea
Chukchi Sea: Arctic marginal sea between Alaska and Russia's Chukchi Peninsula, linked to the Pacific by Bering Strait; shallow 0–50 m shelf carrying ~0.8–1.1 Sv of Pacific water northward, ice-covered about eight months a year, and warming rapidly.
Chuuk Lagoon
Chuuk Lagoon, formerly Truk Lagoon, is a large atoll lagoon in Chuuk State, Federated States of Micronesia. Japan's WWII Combined Fleet base was destroyed by Operation Hailstone in February 1944, leaving over 60 wrecks that made it a premier wreck-diving destination.
Chwaka Bay
Chwaka Bay is a shallow, intertidal bay on the east coast of Unguja Island, Zanzibar, Tanzania, holding Zanzibar's largest mangrove forest and supporting a declining artisanal fishery.
Coast
Coast: the region where land meets the sea, from shoreline to first terrain change. Covers coastal definitions, erosion and longshore processes, 40% of humanity living on coasts, and sea level rise adaptation options.
Coastal area
Coastal area: the land-sea transition zone around the shoreline (also coastal zone). About 40% of humanity lives within 100 km of it; managed through ICZM, marine spatial planning, and ecosystem-based adaptation.
Coastal water
Coastal water: near-shore marine and estuarine waters between land and open ocean; also called inshore or nearshore waters. Definitions vary: NOAA forecasts to 100 nautical miles, EPA to the shelf break, EU WFD to 1 nautical mile.
Cocos Ridge
Cocos Ridge: ~1,000 km long aseismic submarine ridge on the Cocos plate, a Galápagos hotspot trace with ~20 km thick crust, now subducting flatly beneath Costa Rica at the Middle American Trench, driving uplift, subduction erosion, and earthquakes.
Colac Bay
Colac Bay (Ōraka) is a small Southland, New Zealand coastal township 12 km west of Riverton on SH99, facing Foveaux Strait; former 1900 timber-railway town of 2,000, now a holiday and surfing resort with NZ's only surfer statue and Takutai o te Tītī marae.
Columbian exchange
The Columbian exchange is the post-1492 transfer of crops, animals, diseases, and people between the Americas and Afro-Eurasia, a term coined by Alfred Crosby in 1972.
Colville Ridge
Colville Ridge is an underwater volcanic ridge in the southwestern Pacific between New Zealand and Fiji, forming the southernmost 1,300 km of the Lau-Colville Ridge, a remnant volcanic arc west of the Kermadec Arc.
Committee Bay
Committee Bay is a bay in Nunavut, Canada, at 68°16′N, 86°54′W, whose shores host the Committee Bay Greenstone Belt, a roughly 300 km long gold exploration corridor.
Continental rise
Continental rise: the gentle sediment apron between the continental slope and abyssal plain, built by turbidity currents and deep-sea fans, covering about 10% of the ocean floor.