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Distinctive white lines trace the flow of surface currents around the world.

Visualization showing global ocean currents from January 1, 2010, to December 31, 2012, at sea level, then at 2,000 m (6,600 ft) below sea level

Animation of circulation around ice shelves of Antarctica

An ocean current is a continuous, directed movement of seawater generated by a number of forces acting upon the water, including wind, the Coriolis effect, breaking waves, cabbeling, and temperature and salinity differences.^[1] Depth contours, shoreline configurations, and interactions with other currents influence a current's direction and strength. Ocean currents move both horizontally, on scales that can span entire oceans, as well as vertically, with vertical currents (upwelling and downwelling) playing an important role in the movement of nutrients and gases, such as carbon dioxide, between the surface and the deep ocean.

Ocean currents flow for great distances and together they create the global conveyor belt, which plays a dominant role in determining the climate of many of Earth's regions. More specifically, ocean currents influence the temperature of the regions through which they travel. For example, warm currents traveling along more temperate coasts increase the temperature of the area by warming the sea breezes that blow over them. Perhaps the most striking example is the Gulf Stream, which, together with its extension the North Atlantic Drift, makes northwest Europe much more temperate for its high latitude than other areas at the same latitude. Another example is Lima, Peru, whose cooler subtropical climate contrasts with that of its surrounding tropical latitudes because of the Humboldt Current.

The largest ocean current is the Antarctic Circumpolar Current (ACC), a wind-driven current which flows clockwise uninterrupted around Antarctica. The ACC connects all the ocean basins together, and also provides a link between the atmosphere and the deep ocean due to the way water upwells and downwells on either side of it.

Ocean currents are patterns of water movement that influence climate zones and weather patterns around the world. They are primarily driven by winds and by seawater density, although many other factors influence them – including the shape and configuration of the ocean basin they flow through. The two basic types of currents – surface and deep-water currents – help define the character and flow of ocean waters across the planet.the ocean current is divided in to two warm ocean current and cold ocean current

Causes

Ocean currents are driven by the wind, by the gravitational pull of the moon in the form of tides, and by the effects of variations in water density.^[4] Ocean dynamics define and describe the motion of water within the oceans.

Ocean temperature and motion fields can be separated into three distinct layers: mixed (surface) layer, upper ocean (above the thermocline), and deep ocean. Ocean currents are measured in units of sverdrup (Sv), where 1 Sv is equivalent to a volume flow rate of 1,000,000 m³ (35,000,000 cu ft) per second.

There are two main types of currents, surface currents and deep water currents. Generally surface currents are driven by wind systems and deep water currents are driven by differences in water density due to variations in water temperature and salinity.^[5]

Wind-driven circulation

Surface oceanic currents are driven by wind currents, the large scale prevailing winds drive major persistent ocean currents, and seasonal or occasional winds drive currents of similar persistence to the winds that drive them,^[6] and the Coriolis effect plays a major role in their development.^[7] The Ekman spiral velocity distribution results in the currents flowing at an angle to the driving winds, and they develop typical clockwise spirals in the northern hemisphere and counter-clockwise rotation in the southern hemisphere.^[8] In addition, the areas of surface ocean currents move somewhat with the seasons; this is most notable in equatorial currents.

Deep ocean basins generally have a non-symmetric surface current, in that the eastern equator-ward flowing branch is broad and diffuse whereas the pole-ward flowing western boundary current is relatively narrow.

Thermohaline circulation

Coupling data collected by NASA/JPL by several different satellite-borne sensors, researchers have been able to "break through" the ocean's surface to detect "Meddies" – super-salty warm-water eddies that originate in the Mediterranean Sea and then sink more than a half-mile underwater in the Atlantic Ocean. The Meddies are shown in red in this scientific figure.

Large scale currents are driven by gradients in water density, which in turn depend on variations in temperature and salinity. This thermohaline circulation is also known as the ocean's conveyor belt. Where significant vertical movement of ocean currents is observed, this is known as upwelling and downwelling. The adjective thermohaline derives from thermo- referring to temperature and -haline referring to salt content, factors which together determine the density of seawater.

The thermohaline circulation is a part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes.^[9]^[10] Wind-driven surface currents (such as the Gulf Stream) travel polewards from the equatorial Atlantic Ocean, cooling en route, and eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense water then flows into the ocean basins. While the bulk of it upwells in the Southern Ocean, the oldest waters (with a transit time of around 1000 years)^[11] upwell in the North Pacific.^[12] Extensive mixing therefore takes place between the ocean basins, reducing differences between them and making the Earth's oceans a global system. On their journey, the water masses transport both energy (in the form of heat) and matter (solids, dissolved substances and gases) around the globe. As such, the state of the circulation has a large impact on the climate of the Earth. The thermohaline circulation is sometimes called the ocean conveyor belt, the great ocean conveyor, or the global conveyor belt. On occasion, it is imprecisely used to refer to the meridional overturning circulation, (MOC).

Since the 2000s an international program called Argo has been mapping the temperature and salinity structure of the ocean with a fleet of automated platforms that float with the ocean currents. The information gathered will help explain the role the oceans play in the earth's climate.^[13]

Effects on climate and ecology

Ocean currents affect temperatures throughout the world. For example, the ocean current that brings warm water up the north Atlantic to northwest Europe also cumulatively and slowly blocks ice from forming along the seashores, which would also block ships from entering and exiting inland waterways and seaports, hence ocean currents play a decisive role in influencing the climates of regions through which they flow.^[14] Ocean currents are important in the study of marine debris.^[15]^[16]

Upwellings and cold ocean water currents flowing from polar and sub-polar regions bring in nutrients that support plankton growth, which are crucial prey items for several key species in marine ecosystems.^[17]

Ocean currents are also important in the dispersal and distribution of many organisms, inclusing those with pelagic egg or larval stages.^[18] An example is the life-cycle of the European Eel. Terrestrial species, for example tortoises and lizards, can be carried on floating debris by currents to colonise new terrestrial areas and islands.^[18]

Ocean currents and climate change

The continued rise of atmospheric temperatures is anticipated to have various effects on the strength of surface ocean currents, wind-driven circulation and dispersal patterns.^[19]^[20]^[21] Ocean currents play a significant role in influencing climate, and shifts in climate in turn impact ocean currents.^[20]

Over the last century, reconstructed sea surface temperature data reveal that western boundary currents are heating at double the rate of the global average.^[22] These observations indicate that the western boundary currents are likely intensifying due to this change in temperature, and may continue to grow stronger in the near future.^[20] There is evidence that surface warming due to anthropogenic climate change has accelerated upper ocean currents in 77% of the global ocean.^[21] Specifically, increased vertical stratification due to surface warming intensifies upper ocean currents, while changes in horizontal density gradients caused by differential warming across different ocean regions results in the acceleration of surface zonal currents.^[21]

There are suggestions that the Atlantic meridional overturning circulation (AMOC) is in danger of collapsing due to climate change, which would have extreme impacts on the climate of northern Europe and more widely,^[23]^[24]^[25] although this topic is controversial and remains an active area of research.^[26]^[27]^[28] The "State of the cryosphere" report, dedicates significant space to AMOC, saying it may be enroute to collapse because of ice melt and water warming. In the same time, the Antarctic Circumpolar Current (ACC) is also slowing down and is expected to lose 20% of it power by the year 2050, "with widespread impacts on ocean circulation and climate".^[29] UNESCO mentions that the report in the first time "notes a growing scientific consensus that melting Greenland and Antarctic ice sheets, among other factors, may be slowing important ocean currents at both poles, with potentially dire consequences for a much colder northern Europe and greater sea-level rise along the U.S. East Coast."^[30]

In addition to water surface temperatures, the wind systems are a crucial determinant of ocean currents.^[31] Wind wave systems influence oceanic heat exchange, the condition of the sea surface, and can alter ocean currents.^[32] In the North Atlantic, equatorial Pacific, and Southern Ocean, increased wind speeds as well as significant wave heights have been attributed to climate change and natural processes combined.^[32] In the East Australian Current, global warming has also been accredited to increased wind stress curl, which intensifies these currents, and may even indirectly increase sea levels, due to the additional warming created by stronger currents.^[33]

As ocean circulation changes due to climate, typical distribution patterns are also changing. The dispersal patterns of marine organisms depend on oceanographic conditions, which as a result, influence the biological composition of oceans.^[19] Due to the patchiness of the natural ecological world, dispersal is a species survival mechanism for various organisms.^[34] With strengthened boundary currents moving toward the poles, it is expected that some marine species will be redirected to the poles and greater depths.^[19]^[35] The strengthening or weakening of typical dispersal pathways by increased temperatures are expected to not only impact the survival of native marine species due to inability to replenish their meta populations but also may increase the prevalence of invasive species.^[19] In Japanese corals and macroalgae, the unusual dispersal pattern of organisms toward the poles may destabilize native species.^[36]

Economic importance

Knowledge of surface ocean currents is essential in reducing costs of shipping, since traveling with them reduces fuel costs. In the wind powered sailing-ship era, knowledge of wind patterns and ocean currents was even more essential. Using ocean currents to help their ships into harbor and using currents such as the gulf stream to get back home.^[37] The lack of understanding of ocean currents during that time period is hypothesized to be one of the contributing factors to exploration failure. The Gulf Stream and the Canary current keep western European countries warmer and less variable, while at the same latitude North America's weather was colder.^[38] A good example of this is the Agulhas Current (down along eastern Africa), which long prevented sailors from reaching India.

In recent times, around-the-world sailing competitors make good use of surface currents to build and maintain speed. Ocean currents can also be used for marine power generation, with areas of Japan, Florida and Hawaii being considered for test projects. The utilization of currents today can still impact global trade, it can reduce the cost and emissions of shipping vessels.^[39]

Ocean currents can also impact the fishing industry, examples of this include the Tsugaru, Oyashio and Kuroshio currents all of which influence the western North Pacific temperature, which has been shown to be a habitat predictor for the Skipjack tuna.^[40] It has also been shown that it is not just local currents that can affect a country's economy, but neighboring currents can influence the viability of local fishing industries.^[41]

Distribution

Currents of the Arctic Ocean

Baffin Island Current – Arctic Ocean current
Beaufort Gyre – Wind-driven ocean current in the Arctic Ocean polar region
East Greenland Current – Current from Fram Strait to Cape Farewell off the eastern coat of Greenland
East Iceland Current – Cold water ocean current that forms as a branch of the East Greenland Current
Labrador Current – Cold current in the Atlantic ocean along the coasts of Labrador, Newfoundland and Nova Scotia
North Icelandic Jet – Deep-reaching current that flows along the continental slope of Iceland
Norwegian Current – Current that flows northeasternly along the Atlantic coast of Norway
Transpolar Drift Stream – An ocean current of the Arctic Ocean
West Greenland Current – Weak cold water current that flows to the north along the west coast of Greenland
West Spitsbergen Current – Warm, salty current that runs poleward just west of Spitsbergen

Currents of the Atlantic Ocean

Angola Current – Temporary ocean surface current
Antilles Current – Ocean current
Atlantic meridional overturning circulation – System of surface and deep currents in the Atlantic Ocean
Azores Current – Ocean current in the North Atlantic Ocean
Benguela Current – Ocean current in the South Atlantic
Brazil Current – Warm current that flows south along the Brazilian south coast to the mouth of the Río de la Plata
Canary Current – Wind-driven surface current that is part of the North Atlantic Gyre
Cape Horn Current – Cold water current that flows west-to-east around Cape Horn
Caribbean Current – Atlantic Ocean current
East Greenland Current – Current from Fram Strait to Cape Farewell off the eastern coat of Greenland
East Iceland Current – Cold water ocean current that forms as a branch of the East Greenland Current
Equatorial Counter Current – Shallow eastward flowing current found in the Atlantic, Indian, and Pacific Oceans
Falkland Current – Northward cold water Atlantic Ocean current
Florida Current – Thermal ocean current
Guinea Current – A slow warm water current that flows to the east along the Guinea coast of West Africa
Gulf Stream – Warm Atlantic Ocean current
Irminger Current – north Atlantic current setting westward off the southwest coast of Iceland
Labrador Current – Cold current in the Atlantic ocean along the coasts of Labrador, Newfoundland and Nova Scotia
Lomonosov Current – Deep current in the Atlantic Ocean. from the coast of Brazil to the Gulf of Guinea
Loop Current – Ocean current between Cuba and Yucatán Peninsula
North Atlantic Current – Current of the Atlantic Ocean
North Brazil Current – North Atlantic ocean current
North Equatorial Current – Current in the Pacific and Atlantic Oceans
Norwegian Current – Current that flows northeasternly along the Atlantic coast of Norway
Portugal Current – Weak ocean current that flows south along the coast of Portugal
South Atlantic Current – Eastward ocean current, fed by the Brazil Current
South Equatorial Current – Ocean current in the Pacific, Atlantic, and Indian Ocean
West Greenland Current – Weak cold water current that flows to the north along the west coast of Greenland
West Spitsbergen Current – Warm, salty current that runs poleward just west of Spitsbergen

Currents of the Indian Ocean

Agulhas Current – Western boundary current of the southwest Indian Ocean that flows down the east coast of Africa
Agulhas Return Current – Ocean current in the southern Indian Ocean
East Madagascar Current – Oceanic flow feature near Madagascar
Equatorial Counter Current – Shallow eastward flowing current found in the Atlantic, Indian, and Pacific Oceans
Indian Monsoon Current – Seasonally-varying ocean current regime found in the tropical regions of the northern Indian Ocean
Indonesian Throughflow – Ocean current
Leeuwin Current – Ocean current off Western Australia
Madagascar Current – Ocean current in the West Indian Ocean
Mozambique Current – Warm ocean current in the Indian Ocean
North Madagascar Current – Ocean current near Madagascar that flows into the South Equatorial Current
Somali Current – Ocean boundary current that flows along the coast of Somalia and Oman in the Western Indian Ocean
South Equatorial Current – Ocean current in the Pacific, Atlantic, and Indian Ocean
Southwest Madagascar Coastal Current – Warm poleward ocean current flowing in the south-west of Madagascar
West Australian Current – Cool oceanic current

Currents of the Pacific Ocean

Alaska Current – Warm-water current flowing nortwards along the coast of British Columbia and the Alaska Panhandle
Aleutian Current – Eastward-flowing ocean current which lies north of the North Pacific Current;
California Current – Pacific Ocean current
Cape Horn Current – Cold water current that flows west-to-east around Cape Horn
Cromwell Current – Eastward-flowing subsurface current that extends along the equator in the Pacific Ocean
Davidson Current – Countercurrent of the Pacific Ocean
East Australian Current – Currents of the Pacific Ocean
East Korea Warm Current – Ocean current in the Sea of Japan
Equatorial Counter Current – Shallow eastward flowing current found in the Atlantic, Indian, and Pacific Oceans
Humboldt Current – Current of the Pacific Ocean
Indonesian Throughflow – Ocean current
Kamchatka Current – Pacific Ocean current
Kuroshio Current – North flowing ocean current on the west side of the North Pacific Ocean
Mindanao Current – Narrow, southward-flowing ocean current along the southeastern coast of the Philippines
Mindanao Eddy – Semi-permanent cold-ring eddy formed in the retroflection area of the Mindanao Current.
North Equatorial Current – Current in the Pacific and Atlantic Oceans
North Korea Cold Current – Cold water current in the Sea of Japan
North Pacific Current – Ocean current, Japan to British Columbia
Oyashio Current – Cold subarctic ocean current in the Pacific Ocean
South Equatorial Current – Ocean current in the Pacific, Atlantic, and Indian Ocean
Subtropical Countercurrent – Narrow eastward ocean current in the central North Pacific Ocean
Tasman Front – Pacific Ocean current
Tasman Outflow – Deepwater current that flows from the Pacific Ocean past Tasmania into the Indian Ocean

Currents of the Southern Ocean

Antarctic Circumpolar Current – Ocean current that flows clockwise from west to east around Antarctica
Tasman Outflow – Deepwater current that flows from the Pacific Ocean past Tasmania into the Indian Ocean
Kerguelen deep western boundary current^[2]^[3]

Oceanic gyres

Beaufort Gyre – Wind-driven ocean current in the Arctic Ocean polar region
Indian Ocean Gyre – Major oceanic gyre in the Indian Ocean
North Atlantic Gyre – Major circular system of ocean currents
North Pacific Gyre – Major circulating system of ocean currents
Ross Gyre – Circulating system of ocean currents in the Ross Sea
South Atlantic Gyre – Subtropical gyre in the south Atlantic Ocean
South Pacific Gyre – Major circulating system of ocean currents
Weddell Gyre – One of two gyres within the Southern Ocean

References

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^ National Oceanic and Atmospheric Administration (16 June 2024). "What is a current?". oceanservice.noaa.gov. Retrieved 2024-09-03.
^ National Oceanic and Atmospheric Administration (1 August 2011). "Ocean currents". www.noaa.gov. Retrieved 2024-09-14.{{cite web}}: CS1 maint: date and year (link)
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^ "Ocean Currents of the World: Causes". 29 August 2020. Retrieved 2020-11-20.
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^ Rahmstorf, S (2003). "The concept of the thermohaline circulation" (PDF). Nature. 421 (6924): 699. Bibcode:2003Natur.421..699R. doi:10.1038/421699a. PMID 12610602. S2CID 4414604.
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External links

Current global map of sea surface currents

[NOAAs_National_Ocean_Service_2009-1] "What is a current?". NOAA's National Ocean Service. 2009-03-01. Retrieved 2023-03-14.

[Massive-2] "Massive Southern Ocean current discovered". ScienceDaily. Apr 27, 2010.

[Fukamachi-3] Yasushi Fukamachi, Stephen Rintoul; et al. (Apr 2010). "Strong export of Antarctic Bottom Water east of the Kerguelen plateau". Nature Geoscience. 3 (5): 327–331. Bibcode:2010NatGe...3..327F. doi:10.1038/NGEO842. hdl:2115/44116. S2CID 67815755.

[4] National Oceanic and Atmospheric Administration (16 June 2024). "What is a current?". oceanservice.noaa.gov. Retrieved 2024-09-03.

[5] National Oceanic and Atmospheric Administration (1 August 2011). "Ocean currents". www.noaa.gov. Retrieved 2024-09-14.{{cite web}}: CS1 maint: date and year (link)

[NatGeo_Current-6] "Current". www.nationalgeographic.org. National Geographic. 2 September 2011. Retrieved 7 January 2021.

[7] "Ocean Currents of the World: Causes". 29 August 2020. Retrieved 2020-11-20.

[NNOAACurrents-8] National Ocean Service (March 25, 2008). "Surface Ocean Currents". noaa.gov. National Oceanic and Atmospheric Administration. Archived from the original on July 6, 2017. Retrieved 2017-06-13.

[9] Rahmstorf, S (2003). "The concept of the thermohaline circulation" (PDF). Nature. 421 (6924): 699. Bibcode:2003Natur.421..699R. doi:10.1038/421699a. PMID 12610602. S2CID 4414604.

[10] Lappo, SS (1984). "On reason of the northward heat advection across the Equator in the South Pacific and Atlantic ocean". Study of Ocean and Atmosphere Interaction Processes. Moscow Department of Gidrometeoizdat (in Mandarin): 125–9.

[11] The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity; What is the global ocean conveyor belt?

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@@ Line 1: / Line 1: @@
-{{short description|Directional mass flow of oceanic water generated by external or internal forces }}
+{{short description|Directional mass flow of oceanic water}}
 {{more citations needed|date=January 2014}}
 [[File:Corrientes-oceanicas.png|thumb|upright=2|Ocean surface currents]]
@@ Line 5: / Line 5: @@
 [[File:Ocean flows at surface and 2000 meters below sea level.webm|thumb|Visualization showing global ocean currents from January{{nbsp}}1, 2010, to December{{nbsp}}31, 2012, at sea level, then at {{cvt|2000|m|ft}} below sea level]]
 [[File:Circulation of Ocean Currents Around the Western Antarctic Ice Shelves.ogv|thumb|Animation of circulation around [[ice shelf|ice shelves]] of [[Antarctica]]]]
-An '''ocean current''' is a continuous, directed movemenvbvhjgjgt of [[seawater]] generated by a number of forces acting upon the water, including wind, the [[Coriolis effect]], [[breaking wave]]s, [[cabbeling]], and temperature and [[salinity]] differences.<ref name="NOAAs National Ocean Service 2009" /> [[Depth contour]]s, shoreline configurations, and interactions with other currents influence a current's direction and strength. Ocean currents are primarily horizontal water movements.
+An '''ocean current''' is a continuous, directed movement of [[seawater]] generated by a number of forces acting upon the water, including wind, the [[Coriolis effect]], [[breaking wave]]s, [[cabbeling]], and temperature and [[salinity]] differences.<ref name="NOAAs National Ocean Service 2009">{{cite web |date=2009-03-01 |title=What is a current? |url=https://oceanservice.noaa.gov/facts/current.html |access-date=2023-03-14 |website=NOAA's National Ocean Service}}</ref> [[Depth contour]]s, shoreline configurations, and interactions with other currents influence a current's direction and strength. Ocean currents move both horizontally, on scales that can span entire oceans, as well as vertically, with vertical currents ([[upwelling]] and [[downwelling]]) playing an important role in the movement of nutrients and gases, such as carbon dioxide, between the surface and the deep ocean.
-An ocean current flows for great distances and together they create the [[global conveyor belt]], which plays a dominant role in determining the [[climate]] of many of Earth's regions. More specifically, ocean currents influence the temperature of the regions through which they travel.  For example, warm currents traveling along more temperate coasts increase the temperature of the area by warming the sea breezes that blow over them.  Perhaps the most striking example is the [[Gulf Stream]], which, together with its extension the [[North Atlantic Drift]], makes [[northwest Europe]] much more [[temperate climate|temperate]] for its high latitude than other areas at the same latitude. Another example is [[Lima, Peru]], whose cooler [[subtropics|subtropical climate]] contrasts with that of its surrounding tropical latitudes because of the [[Humboldt Current]]. Ocean currents are patterns of water movement that influence climate zones and weather patterns around the world. They are primarily driven by winds and by seawater density, although many other factors – including the shape and configuration of the [[Oceanic basin|ocean basin]] they flow through – influence them. The two basic types of currents – surface and deep-water currents – help define the character and flow of ocean waters across the planet.
+Ocean currents flow for great distances and together they create the [[global conveyor belt]], which plays a dominant role in determining the [[climate]] of many of Earth's regions. More specifically, ocean currents influence the temperature of the regions through which they travel. For example, warm currents traveling along more temperate coasts increase the temperature of the area by warming the sea breezes that blow over them. Perhaps the most striking example is the [[Gulf Stream]], which, together with its extension the [[North Atlantic Drift]], makes [[northwest Europe]] much more [[temperate climate|temperate]] for its high latitude than other areas at the same latitude. Another example is [[Lima, Peru]], whose cooler [[subtropics|subtropical climate]] contrasts with that of its surrounding tropical latitudes because of the [[Humboldt Current]].
+The largest ocean current is the [[Antarctic Circumpolar Current]] (ACC), a wind-driven current which flows clockwise uninterrupted around Antarctica. The ACC connects all the ocean basins together, and also provides a link between the atmosphere and the deep ocean due to the way water upwells and downwells on either side of it.
+Ocean currents are patterns of water movement that influence climate zones and weather patterns around the world. They are primarily driven by winds and by seawater density, although many other factors influence them – including the shape and configuration of the [[Oceanic basin|ocean basin]] they flow through. The two basic types of currents – surface and deep-water currents – help define the character and flow of ocean waters across the planet.the ocean current is divided in to two warm ocean current and cold ocean current
 == Causes ==
 [[File:CSIRO ScienceImage 11128 The bathymetry of the Kerguelen Plateau in the Southern Ocean governs the course of the new current part of the global network of ocean currents.jpg|thumb|right|The [[bathymetry]] of the [[Kerguelen Plateau]] in the [[Southern Ocean]] governs the course of the [[Kerguelen deep western boundary current]], part of the global network of ocean currents.<ref name=Massive>{{cite web |title=Massive Southern Ocean current discovered |url=https://www.sciencedaily.com/releases/2010/04/100427101234.htm |website=ScienceDaily |date=Apr 27, 2010}}</ref><ref name=Fukamachi>{{cite journal |display-authors=etal|last1=Yasushi Fukamachi, Stephen Rintoul |title=Strong export of Antarctic Bottom Water east of the Kerguelen plateau |journal=Nature Geoscience |date=Apr 2010 |volume=3 |issue=5 |pages=327–331 |doi=10.1038/NGEO842 |bibcode=2010NatGe...3..327F |hdl=2115/44116 |s2cid=67815755 |url=https://www.researchgate.net/publication/47656862|hdl-access=free }}</ref>]]
+Ocean currents are driven by the wind, by the gravitational pull of the moon in the form of [[Tide|tides]], and by the effects of variations in water density.<ref>{{Cite web |last=National Oceanic and Atmospheric Administration |date=16 June 2024 |title=What is a current? |url=https://oceanservice.noaa.gov/facts/current.html#:~:text=Ocean%20currents%20are%20driven%20by,or%201.15%20miles%20per%20hour). |access-date=2024-09-03 |website=oceanservice.noaa.gov |language=EN-US}}</ref> [[Ocean dynamics]] define and describe the motion of water within the oceans.
-[[Ocean dynamics]] define and describe the motion of water within the oceans. Ocean temperature and motion fields can be separated into three distinct layers: mixed (surface) layer, upper ocean (above the thermocline), and deep ocean. Ocean currents are measured in [[physical unit|units]] of [[Sverdrup|sverdrup (sv)]], where 1 sv is equivalent to a [[volume flow rate]] of {{convert|1000000|m3|ft3|abbr=on}} per second.
+Ocean temperature and motion fields can be separated into three distinct layers: mixed (surface) layer, upper ocean (above the thermocline), and deep ocean. Ocean currents are measured in [[physical unit|units]] of [[Sverdrup|sverdrup (Sv)]], where 1 Sv is equivalent to a [[volume flow rate]] of {{convert|1000000|m3|ft3|abbr=on}} per second.
+There are two main types of currents, surface currents and deep water currents. Generally surface currents are driven by wind systems and deep water currents are driven by differences in water density due to variations in water temperature and [[salinity]].<ref>{{Cite web |last=National Oceanic and Atmospheric Administration |date=1 August 2011 |year=2011 |title=Ocean currents |url=https://www.noaa.gov/education/resource-collections/ocean-coasts/ocean-currents#:~:text=via%20research%20ship.-,Surface%20currents,influencing%20local%20and%20global%20climate. |access-date=2024-09-14 |website=www.noaa.gov |language=en}}</ref>
-'''Surface ocean currents''' (in contrast to ''[[subsurface ocean current]]s''), make up only 8% of all water in the ocean, are generally restricted to the upper {{convert|400|m|ft|abbr=on}} of ocean water, and are separated from lower regions by varying temperatures and [[salinity]] which affect the density of the water, which in turn, defines each oceanic region. Because the movement of deep water in ocean basins is caused by density-driven forces and gravity, deep waters sink into deep ocean basins at high latitudes where the temperatures are cold enough to cause the density to increase.
-Surface currents are measured in units of [[meters per second]] (m/s) or in [[knot (unit)|knots]].<ref name="NOAAs National Ocean Service 2009">{{cite web | title=What is a current? | website=NOAA's National Ocean Service | date=2009-03-01 | url=https://oceanservice.noaa.gov/facts/current.html | access-date=2023-03-14}}</ref>
 === Wind-driven circulation ===
@@ Line 25: / Line 30: @@
 === Thermohaline circulation ===
 {{main|Thermohaline circulation}}
+{{Further|Deep ocean water}}[[File:Meddes-20060320-browse.jpg|thumb|Coupling data collected by NASA/JPL by several different satellite-borne sensors, researchers have been able to "break through" the ocean's surface to detect "Meddies" – super-salty warm-water eddies that originate in the Mediterranean Sea and then sink more than a half-mile underwater in the Atlantic Ocean. The Meddies are shown in red in this scientific figure.]]
-{{Further|Deep ocean water}}
-Deep ocean currents are driven by [[density]] and temperature gradients. This [[thermohaline circulation]] is also known as the ocean's conveyor belt. These currents, sometimes called submarine rivers, flow deep below the surface of the ocean and are hidden from immediate detection. Where significant vertical movement of ocean currents is observed, this is known as [[upwelling]] and [[downwelling]]. An international program called [[Argo (oceanography)|Argo]] began researching deep ocean currents with a fleet of underwater robots in the 2000s.
+Large scale currents are driven by gradients in water [[density]], which in turn depend on variations in temperature and salinity. This [[thermohaline circulation]] is also known as the ocean's conveyor belt. Where significant vertical movement of ocean currents is observed, this is known as [[upwelling]] and [[downwelling]]. The adjective ''thermohaline'' derives from ''[[wikt:thermo-|thermo-]]'' referring to [[temperature]] and ''{{nowrap|-haline}}'' referring to [[salinity|salt content]], factors which together determine the density of seawater.
-The thermohaline circulation is a part of the large-scale ocean circulation that is driven by global [[density gradient]]s created by surface heat and freshwater [[flux]]es.<ref>{{cite journal|last=Rahmstorf|first=S|title=The concept of the thermohaline circulation|journal=Nature|volume=421|page=699|year=2003|url=http://www.pik-potsdam.de/~stefan/Publications/Nature/nature_concept_03.pdf|pmid=12610602|issue=6924|doi=10.1038/421699a|bibcode = 2003Natur.421..699R |s2cid=4414604|doi-access=free}}</ref><ref>{{cite journal|last=Lappo|first=SS|title=On reason of the northward heat advection across the Equator in the South Pacific and Atlantic ocean|journal=Study of Ocean and Atmosphere Interaction Processes|year=1984|pages=125–9|publisher=Moscow Department of Gidrometeoizdat (in Mandarin)}}</ref> The adjective ''thermohaline'' derives from ''[[wikt:thermo-|thermo-]]'' referring to [[temperature]] and ''{{nowrap|-haline}}'' referring to [[salinity|salt content]], factors which together determine the [[density of sea water]]. [[Wind]]-driven surface currents (such as the [[Gulf Stream]]) travel [[Polar regions of Earth|polewards]] from the equatorial [[Atlantic Ocean]], cooling en route, and eventually sinking at high [[latitude]]s (forming [[North Atlantic Deep Water]]). This dense water then flows into the [[ocean basin]]s. While the bulk of it [[upwelling|upwells]] in the [[Southern Ocean]], the oldest waters (with a transit time of around 1000 years)<ref>The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity; [http://oceanservice.noaa.gov/facts/conveyor.html What is the global ocean conveyor belt?]</ref> upwell in the North Pacific.<ref>{{cite journal|doi=10.1175/JPO2699.1|last=Primeau|first=F|title=Characterizing transport between the surface mixed layer and the ocean interior with a forward and adjoint global ocean transport model|journal=Journal of Physical Oceanography|volume=35|issue=4|pages=545–64|year=2005|bibcode=2005JPO....35..545P|s2cid=130736022 |url=https://escholarship.org/content/qt5f76r4wn/qt5f76r4wn.pdf?t=n3tp5j}}</ref> Extensive mixing therefore takes place between the ocean basins, reducing differences between them and making the Earth's oceans a global system. On their journey, the water masses transport both energy (in the form of heat) and matter (solids, dissolved substances and gases) around the globe. As such, the state of the circulation has a large impact on the [[climate]] of the Earth. The thermohaline circulation is sometimes called the ocean conveyor belt, the great ocean conveyor, or the global conveyor belt. On occasion, it is imprecisely used to refer to the [[meridional overturning circulation]], (MOC).
+The thermohaline circulation is a part of the large-scale ocean circulation that is driven by global [[density gradient]]s created by surface heat and freshwater [[flux]]es.<ref>{{cite journal|last=Rahmstorf|first=S|title=The concept of the thermohaline circulation|journal=Nature|volume=421|page=699|year=2003|url=http://www.pik-potsdam.de/~stefan/Publications/Nature/nature_concept_03.pdf|pmid=12610602|issue=6924|doi=10.1038/421699a|bibcode = 2003Natur.421..699R |s2cid=4414604|doi-access=free}}</ref><ref>{{cite journal|last=Lappo|first=SS|title=On reason of the northward heat advection across the Equator in the South Pacific and Atlantic ocean|journal=Study of Ocean and Atmosphere Interaction Processes|year=1984|pages=125–9|publisher=Moscow Department of Gidrometeoizdat (in Mandarin)}}</ref> [[Wind]]-driven surface currents (such as the [[Gulf Stream]]) travel [[Polar regions of Earth|polewards]] from the equatorial [[Atlantic Ocean]], cooling en route, and eventually sinking at high [[latitude]]s (forming [[North Atlantic Deep Water]]). This dense water then flows into the [[ocean basin]]s. While the bulk of it [[upwelling|upwells]] in the [[Southern Ocean]], the oldest waters (with a transit time of around 1000 years)<ref>The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity; [http://oceanservice.noaa.gov/facts/conveyor.html What is the global ocean conveyor belt?]</ref> upwell in the North Pacific.<ref>{{cite journal|doi=10.1175/JPO2699.1|last=Primeau|first=F|title=Characterizing transport between the surface mixed layer and the ocean interior with a forward and adjoint global ocean transport model|journal=Journal of Physical Oceanography|volume=35|issue=4|pages=545–64|year=2005|doi-broken-date=1 December 2024 |bibcode=2005JPO....35..545P|s2cid=130736022 |url=https://escholarship.org/content/qt5f76r4wn/qt5f76r4wn.pdf?t=n3tp5j}}</ref> Extensive mixing therefore takes place between the ocean basins, reducing differences between them and making the Earth's oceans a global system. On their journey, the water masses transport both energy (in the form of heat) and matter (solids, dissolved substances and gases) around the globe. As such, the state of the circulation has a large impact on the [[climate]] of the Earth. The thermohaline circulation is sometimes called the ocean conveyor belt, the great ocean conveyor, or the global conveyor belt. On occasion, it is imprecisely used to refer to the [[meridional overturning circulation]], (MOC).
+Since the 2000s an international program called [[Argo (oceanography)|Argo]] has been mapping the temperature and salinity structure of the ocean with a fleet of automated platforms that float with the ocean currents. The information gathered will help explain the role the oceans play in the earth's climate.<ref>{{Cite web |last=Scripps Institution of Oceanography, UC San Diego |title=Argo |url=https://argo.ucsd.edu/ |archive-url=https://web.archive.org/web/20240901191501/https://argo.ucsd.edu/ |archive-date=1 September 2024 |access-date=2024-09-05 |website=Argo |language=en-US}}</ref>
-[[File:Meddes-20060320-browse.jpg|thumb|Coupling data collected by NASA/JPL by several different satellite-borne sensors, researchers have been able to "break through" the ocean's surface to detect "Meddies" – super-salty warm-water eddies that originate in the Mediterranean Sea and then sink more than a half-mile underwater in the Atlantic Ocean. The Meddies are shown in red in this scientific figure.]]
-[[File:Recording Current Meter.jpg|thumb|left|70px|A recording current meter|alt=Device to record ocean currents]]
+== Effects on climate and ecology ==
+Ocean currents affect temperatures throughout the world. For example, the ocean current that brings warm water up the north Atlantic to northwest Europe also cumulatively and slowly blocks ice from forming along the seashores, which would also block ships from entering and exiting inland waterways and seaports, hence ocean currents play a decisive role in influencing the climates of regions through which they flow.<ref>{{Cite web |title=What Is the Gulf Stream? {{!}} NOAA SciJinks – All About Weather |url=https://scijinks.gov/gulf-stream/ |access-date=2024-04-15 |website=scijinks.gov}}</ref> Ocean currents are important in the study of [[marine debris]].<ref>{{Cite web |last=National Oceanic and Atmospheric Administration |date=1 April 2020 |title=Ocean pollution and marine debris |url=https://www.noaa.gov/education/resource-collections/ocean-coasts/ocean-pollution |access-date=2024-09-08 |website=www.noaa.gov |language=en}}</ref><ref>{{Cite journal |last1=van Sebille |first1=Erik |last2=Aliani |first2=Stefano |last3=Law |first3=Kara Lavender |last4=Maximenko |first4=Nikolai |last5=Alsina |first5=José M |last6=Bagaev |first6=Andrei |last7=Bergmann |first7=Melanie |last8=Chapron |first8=Bertrand |last9=Chubarenko |first9=Irina |last10=Cózar |first10=Andrés |last11=Delandmeter |first11=Philippe |last12=Egger |first12=Matthias |last13=Fox-Kemper |first13=Baylor |last14=Garaba |first14=Shungudzemwoyo P |last15=Goddijn-Murphy |first15=Lonneke |date=2020-02-01 |title=The physical oceanography of the transport of floating marine debris |url=https://iopscience.iop.org/article/10.1088/1748-9326/ab6d7d |journal=Environmental Research Letters |volume=15 |issue=2 |pages=023003 |doi=10.1088/1748-9326/ab6d7d |bibcode=2020ERL....15b3003V |issn=1748-9326|hdl=2117/187082 |hdl-access=free }}</ref>
+[[File:Marine microplankton.jpg|thumb|Plankton are dispersed by ocean currents.]]
+Upwellings and cold ocean water currents flowing from polar and sub-polar regions bring in nutrients that support [[plankton]] growth, which are crucial [[prey]] items for several key species in [[marine ecosystem]]s.<ref>{{Cite book |url=https://linkinghub.elsevier.com/retrieve/pii/B9780126009521X50002 |title=Introduction to the Practice of Fishery Science |date=1996 |publisher=Elsevier |isbn=978-0-12-600952-1 |editor-last=Royce |editor-first=William F. |chapter=Circulation |doi=10.1016/b978-0-12-600952-1.x5000-2}}</ref>
+Ocean currents are also important in the dispersal and distribution of many organisms, inclusing those with [[Pelagic zone|pelagic]] egg or larval stages.<ref name=":4" /> An example is the [[Eel life history|life-cycle of the European Eel]]. Terrestrial species, for example tortoises and lizards, can be carried on floating debris by currents to colonise new terrestrial areas and [[Island#Dispersal|islands]].<ref name=":4">{{Cite journal |last=Hays |first=Graeme C. |date=5 June 2017 |title=Ocean currents and marine life |url=https://linkinghub.elsevier.com/retrieve/pii/S0960982217300775 |journal=Current Biology |language=en |volume=27 |issue=11 |pages=R470–R473 |doi=10.1016/j.cub.2017.01.044|pmid=28586681 |bibcode=2017CBio...27.R470H }}</ref>
+== Ocean currents and climate change ==
+The continued rise of atmospheric temperatures is anticipated to have various effects on the strength of surface ocean currents, wind-driven circulation and dispersal patterns.<ref name=":0">{{Cite journal |last1=Wilson |first1=Laura J. |last2=Fulton |first2=Christopher J. |last3=Hogg |first3=Andrew McC |last4=Joyce |first4=Karen E. |last5=Radford |first5=Ben T. M. |last6=Fraser |first6=Ceridwen I. |date=2016-05-02 |title=Climate-driven changes to ocean circulation and their inferred impacts on marine dispersal patterns |url=https://onlinelibrary.wiley.com/doi/10.1111/geb.12456 |journal=Global Ecology and Biogeography |language= |volume=25 |issue=8 |pages=923–939 |doi=10.1111/geb.12456 |bibcode=2016GloEB..25..923W |issn=1466-822X}}</ref><ref name=":1">{{Cite journal |last=Miller |first=Johanna L. |date=2017 |title=Ocean currents respond to climate change in unexpected ways |url=https://pubs.aip.org/physicstoday/article/70/1/17/1040900 |journal=Physics Today |volume=70 |issue=1 |pages=17–18}}</ref><ref name=":2">{{Cite journal |last1=Peng |first1=Qihua |last2=Xie |first2=Shang-Ping |last3=Wang |first3=Dongxiao |last4=Huang |first4=Rui Xin |last5=Chen |first5=Gengxin |last6=Shu |first6=Yeqiang |last7=Shi |first7=Jia-Rui |last8=Liu |first8=Wei |date=2022-04-22 |title=Surface warming–induced global acceleration of upper ocean currents |journal=Science Advances |volume=8 |issue=16 |pages=eabj8394 |doi=10.1126/sciadv.abj8394 |issn=2375-2548 |pmc=9020668 |pmid=35442733|bibcode=2022SciA....8J8394P }}</ref> Ocean currents play a significant role in influencing climate, and shifts in climate in turn impact ocean currents.<ref name=":1" />
+[[File:Fig 1.4.1 Atmospheric circulation cells, dominant wind directions.png|thumb|Human-induced climate change is leading to long-term alterations in ocean and atmospheric circulation. The accumulation of greenhouse gases traps extra heat within the Earth’s system, causing both the atmosphere and oceans to warm. Notably, over 90% of this trapped heat is absorbed by the oceans. There are signs that crucial circulation patterns are shifting, with growing evidence suggesting that the Atlantic Meridional Overturning Circulation may be slowing down.]]
+Over the last century, reconstructed sea surface temperature data reveal that western [[boundary current]]s are heating at double the rate of the global average.<ref>{{Cite journal |last1=Wu |first1=Lixin |last2=Cai |first2=Wenju |last3=Zhang |first3=Liping |last4=Nakamura |first4=Hisashi |last5=Timmermann |first5=Axel |last6=Joyce |first6=Terry |last7=McPhaden |first7=Michael J. |last8=Alexander |first8=Michael |last9=Qiu |first9=Bo |last10=Visbeck |first10=Martin |last11=Chang |first11=Ping |last12=Giese |first12=Benjamin |date=2012-01-29 |title=Enhanced warming over the global subtropical western boundary currents |url=https://www.nature.com/articles/nclimate1353 |journal=Nature Climate Change |volume=2 |issue=3 |pages=161–166 |doi=10.1038/nclimate1353 |bibcode=2012NatCC...2..161W |issn=1758-6798|hdl=1912/5125 |hdl-access=free }}</ref> These observations indicate that the western boundary currents are likely intensifying due to this change in temperature, and may continue to grow stronger in the near future.<ref name=":1" /> There is evidence that surface warming due to anthropogenic [[climate change]] has accelerated upper ocean currents in 77% of the global ocean.<ref name=":2" /> Specifically, increased vertical [[Ocean stratification|stratification]] due to surface warming intensifies upper ocean currents, while changes in horizontal density gradients caused by differential warming across different ocean regions results in the acceleration of surface [[Zonal and meridional flow|zonal currents]].<ref name=":2" />
+There are suggestions that the [[Atlantic meridional overturning circulation]] (AMOC) is in danger of collapsing due to climate change, which would have extreme impacts on the climate of northern Europe and more widely,<ref>{{Cite journal |last1=Ditlevsen |first1=Peter |last2=Ditlevsen |first2=Susanne |date=2023-07-25 |title=Warning of a forthcoming collapse of the Atlantic meridional overturning circulation |journal=Nature Communications |volume=14 |issue=1 |pages=4254 |doi=10.1038/s41467-023-39810-w |issn=2041-1723 |pmid=37491344|pmc=10368695 }}</ref><ref>{{Cite journal |last1=Zhu |first1=Chenyu |last2=Liu |first2=Zhengyu |last3=Zhang |first3=Shaoqing |last4=Wu |first4=Lixin |date=2023-03-04 |title=Likely accelerated weakening of Atlantic overturning circulation emerges in optimal salinity fingerprint |journal=Nature Communications |language=en |volume=14 |issue=1 |pages=1245 |doi=10.1038/s41467-023-36288-4 |pmid=36871075 |issn=2041-1723|pmc=9985640 }}</ref><ref>{{Cite journal |last1=Boulton |first1=Chris A. |last2=Allison |first2=Lesley C. |last3=Lenton |first3=Timothy M. |date=2014-12-08 |title=Early warning signals of Atlantic Meridional Overturning Circulation collapse in a fully coupled climate model |journal=Nature Communications |language=en |volume=5 |issue=1 |pages=5752 |doi=10.1038/ncomms6752 |pmid=25482065 |issn=2041-1723|pmc=4268699 }}</ref> although this topic is controversial and remains an active area of research.<ref>{{Cite web |last=Science Media Centre |date=25 July 2023 |title=Expert reaction to paper warning of a collapse of the Atlantic meridional overturning circulation |url=https://www.sciencemediacentre.org/expert-reaction-to-paper-warning-of-a-collapse-of-the-atlantic-meridional-overturning-circulation/ |access-date=2024-09-12 |website=Science Media Centre |language=en-GB}}</ref><ref>{{Cite journal |last=Rahmstorf |first=Stefan |date=10 April 2024 |title=Is the Atlantic Overturning Circulation Approaching a Tipping Point? |url=https://tos.org/oceanography/article/is-the-atlantic-overturning-circulation-approaching-a-tipping-point |journal=Oceanography |volume=37 |issue=3 |pages=1–0 |doi=10.5670/oceanog.2024.501|doi-access=free }}</ref><ref>{{Cite web |last=Met Office Press |date=2 May 2024 |title=The Atlantic Meridional Overturning Circulation in a changing climate |url=https://blog.metoffice.gov.uk/2024/05/02/the-atlantic-meridional-overturning-circulation-in-a-changing-climate/ |access-date=2024-09-12 |website=Official blog of the Met Office news team |language=en}}</ref> The "State of the cryosphere" report, dedicates significant space to AMOC, saying it may be enroute to collapse because of ice melt and water warming. In the same time, the [[Antarctic Circumpolar Current |Antarctic Circumpolar Current (ACC)]] is also slowing down and is expected to lose 20% of it power by the year 2050, "with widespread impacts on ocean circulation and climate".<ref>{{cite book |title=State of the Cryosphere 2024 Lost Ice, Global Damage |date=November 2024 |publisher=International Cryosphere Climate Initiative |pages=x (in the beginning), 8, 48, 52 |url=https://articles.unesco.org/sites/default/files/medias/fichiers/2024/11/State%20of%20the%20Cryosphere%20Report%202024.pdf |access-date=20 November 2024}}</ref> [[UNESCO]] mentions that the report in the first time "notes a growing scientific consensus that melting Greenland and Antarctic ice sheets, among other factors, may be slowing important ocean currents at both poles, with potentially dire consequences for a much colder northern Europe and greater sea-level rise along the U.S. East Coast."<ref>{{cite web |title=State of the Cryosphere Report 2024 Lost Ice, Global Damage |url=https://www.unesco.org/en/articles/state-cryosphere-report-2024 |website=UNESCO |access-date=20 November 2024}}</ref>
+In addition to water surface temperatures, the wind systems are a crucial determinant of ocean currents.<ref>{{Cite journal |last=Constantin |first=Adrian |date=2021-01-02 |title=Frictional effects in wind-driven ocean currents |journal=Geophysical & Astrophysical Fluid Dynamics |volume=115 |issue=1 |pages=1–14 |doi=10.1080/03091929.2020.1748614 |issn=0309-1929|doi-access=free |bibcode=2021GApFD.115....1C }}</ref> Wind wave systems influence oceanic heat exchange, the condition of the sea surface, and can alter ocean currents.<ref name=":3">{{Cite journal |last1=Dobrynin |first1=Mikhail |last2=Murawski |first2=Jens |last3=Baehr |first3=Johanna |last4=Ilyina |first4=Tatiana |date=2015-02-15 |title=Detection and Attribution of Climate Change Signal in Ocean Wind Waves |url=https://journals.ametsoc.org/view/journals/clim/28/4/jcli-d-13-00664.1.xml |journal=Journal of Climate |volume=28 |issue=4 |pages=1578–1591 |doi=10.1175/JCLI-D-13-00664.1 |doi-broken-date=1 December 2024 |bibcode=2015JCli...28.1578D |issn=0894-8755}}</ref> In the North Atlantic, equatorial Pacific, and Southern Ocean, increased wind speeds as well as significant wave heights have been attributed to climate change and natural processes combined.<ref name=":3" /> In the [[East Australian Current]], global warming has also been accredited to increased [[wind stress]] [[Curl (mathematics)|curl]], which intensifies these currents, and may even indirectly increase sea levels, due to the additional warming created by stronger currents.<ref>{{Cite journal |last1=Cai |first1=W. |last2=Shi |first2=G. |last3=Cowan |first3=T. |last4=Bi |first4=D. |last5=Ribbe |first5=J. |date=2005-12-10 |title=The response of the Southern Annular Mode, the East Australian Current, and the southern mid-latitude ocean circulation to global warming |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2005GL024701 |journal=Geophysical Research Letters |volume=32 |issue=23 |doi=10.1029/2005GL024701 |bibcode=2005GeoRL..3223706C |issn=0094-8276}}</ref>
+As ocean circulation changes due to climate, typical distribution patterns are also changing. The [[Biological dispersal|dispersal patterns]] of marine organisms depend on oceanographic conditions, which as a result, influence the biological composition of oceans.<ref name=":0" /> Due to the patchiness of the natural ecological world, dispersal is a species survival mechanism for various organisms.<ref>{{Cite journal |last=Kininmonth |first=Stuart |date=2011-04-11 |title=Dispersal connectivity and reserve selection for marine conservation |url=https://www.sciencedirect.com/science/article/abs/pii/S0304380011000445 |journal=Ecological Modelling |volume=222 |issue=7 |pages=1272–1282|doi=10.1016/j.ecolmodel.2011.01.012 |bibcode=2011EcMod.222.1272K }}</ref> With strengthened boundary currents moving toward the poles, it is expected that some marine species will be redirected to the poles and greater depths.<ref name=":0" /><ref>{{Cite journal |last1=Vergés |first1=Adriana |last2=Steinberg |first2=Peter D. |last3=Hay |first3=Mark E. |last4=Poore |first4=Alistair G. B. |last5=Campbell |first5=Alexandra H. |last6=Ballesteros |first6=Enric |last7=Heck |first7=Kenneth L. |last8=Booth |first8=David J. |last9=Coleman |first9=Melinda A. |last10=Feary |first10=David A. |last11=Figueira |first11=Will |last12=Langlois |first12=Tim |last13=Marzinelli |first13=Ezequiel M. |last14=Mizerek |first14=Toni |last15=Mumby |first15=Peter J. |date=2014-08-22 |title=The tropicalization of temperate marine ecosystems: climate-mediated changes in herbivory and community phase shifts |journal=Proceedings of the Royal Society B: Biological Sciences |volume=281 |issue=1789 |pages=20140846 |doi=10.1098/rspb.2014.0846 |issn=0962-8452 |pmc=4100510 |pmid=25009065}}</ref> The strengthening or weakening of typical dispersal pathways by increased temperatures are expected to not only impact the survival of native marine species due to inability to replenish their [[Metapopulation|meta populations]] but also may increase the prevalence of [[invasive species]].<ref name=":0" /> In Japanese corals and macroalgae, the unusual dispersal pattern of organisms toward the poles may destabilize native species.<ref>{{Cite journal |last1=Kumagai |first1=Naoki H. |last2=García Molinos |first2=Jorge |last3=Yamano |first3=Hiroya |last4=Takao |first4=Shintaro |last5=Fujii |first5=Masahiko |last6=Yamanaka |first6=Yasuhiro |date=2018-09-04 |title=Ocean currents and herbivory drive macroalgae-to-coral community shift under climate warming |journal=Proceedings of the National Academy of Sciences |volume=115 |issue=36 |pages=8990–8995 |doi=10.1073/pnas.1716826115 |doi-access=free |issn=0027-8424 |pmc=6130349 |pmid=30126981|bibcode=2018PNAS..115.8990K }}</ref>
+== Economic importance ==
+Knowledge of  surface ocean currents is essential in reducing costs of shipping, since traveling with them reduces fuel costs. In the wind powered [[Sailing ship|sailing-ship]] era, knowledge of wind patterns and ocean currents was even more essential. Using ocean currents to help their ships into harbor and using currents such as the gulf stream to get back home.<ref>{{Cite web |title=Atlantic Ocean - Exploration, Currents, Marine Life {{!}} Britannica |url=https://www.britannica.com/place/Atlantic-Ocean/Study-and-exploration |access-date=2024-04-20 |website=www.britannica.com }}</ref> The lack of understanding of ocean currents during that time period is hypothesized to be one of the contributing factors to exploration failure. The Gulf Stream and the Canary current keep western European countries warmer and less variable, while at the same latitude North America's weather was colder.<ref>{{Cite web |last=US Department of Commerce |first=National Oceanic and Atmospheric Administration |title=Boundary Currents - Currents: NOAA's National Ocean Service Education |url=https://oceanservice.noaa.gov/education/tutorial_currents/04currents3.html#:~:text=The%20Gulf%20Stream%20is%20a,current%20is%20the%20Gulf%20Stream |access-date=2024-04-20 |website=oceanservice.noaa.gov }}</ref> A good example of this is the [[Agulhas Current]] (down along eastern Africa), which long prevented sailors from reaching India.
+In recent times, around-the-world sailing competitors make good use of surface currents to build and maintain speed.
+Ocean currents can also be used for [[Marine current power|marine power generation]], with areas of Japan, Florida and Hawaii being considered for test projects. The utilization of currents today can still impact global trade, it can reduce the cost and emissions of shipping vessels.<ref>{{Cite journal |last1=Chang |first1=Yu-Chia |last2=Tseng |first2=Ruo-Shan |last3=Chen |first3=Guan-Yu |last4=Chu |first4=Peter C. |last5=Shen |first5=Yung-Ting |date=November 2013 |title=Ship Routing Utilizing Strong Ocean Currents |url=https://www.cambridge.org/core/journals/journal-of-navigation/article/abs/ship-routing-utilizing-strong-ocean-currents/02039ECA1A45DCDD0B7935C94F79CBB9 |journal=The Journal of Navigation |volume=66 |issue=6 |pages=825–835 |doi=10.1017/S0373463313000441 |issn=0373-4633}}</ref>
+[[File:Skipjack tuna transporting at Pondokdadap Fishingport.jpg|thumb|Skipjack tuna fishery in Indonesia.]]
+Ocean currents can also impact the [[fishing industry]], examples of this include the [[Tsugaru current|Tsugaru]], [[Oyashio Current|Oyashio]] and [[Kuroshio Current|Kuroshio]] currents all of which influence the western North Pacific temperature, which has been shown to be a habitat predictor for the [[Skipjack tuna]].<ref>{{Cite journal |last1=Ramesh |first1=Nandini |last2=Rising |first2=James A. |last3=Oremus |first3=Kimberly L. |date=2019-06-21 |title=The small world of global marine fisheries: The cross-boundary consequences of larval dispersal |url=https://www.science.org/doi/10.1126/science.aav3409 |journal=Science |volume=364 |issue=6446 |pages=1192–1196 |doi=10.1126/science.aav3409 |pmid=31221860 |bibcode=2019Sci...364.1192R |issn=0036-8075}}</ref> It has also been shown that it is not just local currents that can affect a country's economy, but neighboring currents can influence the viability of local fishing industries.<ref>{{Cite journal |last=Talley |first=Lynne D. |date=April 1, 1995 |title=North Pacific Intermediate Water in the Kuroshio/Oyashio Mixed Water Region |url=https://journals-ametsoc-org.ezp1.lib.umn.edu/view/journals/phoc/25/4/1520-0485_1995_025_0475_npiwit_2_0_co_2.xml |journal=American Meteorological Society |volume=25 |issue=4 |pages=475–501 |doi=10.1175/1520-0485(1995)025<0475:NPIWIT>2.0.CO;2 |doi-broken-date=1 December 2024 |bibcode=1995JPO....25..475T |via=AMS Publications|doi-access=free }}</ref>
 == Distribution ==
@@ Line 37: / Line 67: @@
 [[Image:Ocean currents 1943 (borderless)3.png|thumb|right|250px|A 1943 map of the world's ocean currents]]
-Currents of the [[Arctic Ocean]]
+'''Currents of the [[Arctic Ocean]]'''
 * {{annotated link|Baffin Island Current}}
 * {{annotated link|Beaufort Gyre}}
@@ Line 49: / Line 79: @@
 * {{annotated link|West Spitsbergen Current}}
-Currents of the [[Atlantic Ocean]]
+'''Currents of the [[Atlantic Ocean]]'''
+[[File:Recording Current Meter.jpg|thumb|70px|A recording current meter. It records information about currents (speed, direction, depth, temperature).|alt=Device to record ocean currents]]
 * {{annotated link|Angola Current}}
 * {{annotated link|Antilles Current}}
@@ Line 80: / Line 111: @@
 * {{annotated link|West Spitsbergen Current}}
-Currents of the [[Indian Ocean]]
+'''Currents of the [[Indian Ocean]]'''
 * {{annotated link|Agulhas Current}}
 * {{annotated link|Agulhas Return Current}}
@@ Line 96: / Line 127: @@
 * {{annotated link|West Australian Current}}
-Currents of the [[Pacific Ocean]]
+'''Currents of the [[Pacific Ocean]]'''
 * {{annotated link|Alaska Current}}
 * {{annotated link|Aleutian Current}}
@@ Line 121: / Line 152: @@
 * {{annotated link|Tasman Outflow}}
-Currents of the [[Southern Ocean]]
+'''Currents of the [[Southern Ocean]]'''
 * {{annotated link|Antarctic Circumpolar Current}}
 * {{annotated link|Tasman Outflow}}
-* {{annotated link|Kerguelen deep western boundary current}}<ref name=Massive/><ref name=Fukamachi/>
+* {{annotated link|Kerguelen deep western boundary current}}<ref name="Massive" /><ref name="Fukamachi" />
-[[Ocean gyre|Oceanic gyres]]
+[[Ocean gyre|'''Oceanic gyres''']]
 * {{annotated link|Beaufort Gyre}}
 * {{annotated link|Indian Ocean Gyre}}
@@ Line 135: / Line 166: @@
 * {{annotated link|South Pacific Gyre}}
 * {{annotated link|Weddell Gyre}}
-== Effects on climate and ecology ==
-Ocean currents are important in the study of [[marine debris]], and vice versa. These currents also affect temperatures throughout the world. For example, the ocean current that brings warm water up the north Atlantic to northwest Europe also cumulatively and slowly blocks ice from forming along the seashores, which would also block ships from entering and exiting inland waterways and seaports, hence ocean currents play a decisive role in influencing the climates of regions through which they flow.<ref>{{Cite web |title=What Is the Gulf Stream? {{!}} NOAA SciJinks – All About Weather |url=https://scijinks.gov/gulf-stream/ |access-date=2024-04-15 |website=scijinks.gov}}</ref> Cold ocean water currents flowing from polar and sub-polar regions bring in a lot of [[plankton]] that are crucial to the continued survival of several key sea creature species in [[marine ecosystem]]s. Since plankton are the food of fish, abundant fish populations often live where these currents prevail.
-Ocean currents are also very important in the dispersal of many life forms. An example is the [[Eel life history|life-cycle of the European Eel]].
-== Ocean currents and climate change ==
-As atmospheric temperatures continue to rise, this is anticipated to have various effects on the strength of surface ocean currents, wind-driven circulation and dispersal patterns.<ref name=":0">{{Cite journal |last1=Wilson |first1=Laura J. |last2=Fulton |first2=Christopher J. |last3=Hogg |first3=Andrew McC |last4=Joyce |first4=Karen E. |last5=Radford |first5=Ben T. M. |last6=Fraser |first6=Ceridwen I. |date=2016-05-02 |title=Climate-driven changes to ocean circulation and their inferred impacts on marine dispersal patterns |url=https://onlinelibrary.wiley.com/doi/10.1111/geb.12456 |journal=Global Ecology and Biogeography |language= |volume=25 |issue=8 |pages=923–939 |doi=10.1111/geb.12456 |bibcode=2016GloEB..25..923W |issn=1466-822X}}</ref><ref name=":1">{{Cite journal |last=Miller |first=Johanna L. |date=2017 |title=Ocean currents respond to climate change in unexpected ways |url=https://pubs.aip.org/physicstoday/article/70/1/17/1040900 |journal=Physics Today |volume=70 |issue=1 |pages=17–18}}</ref><ref name=":2">{{Cite journal |last1=Peng |first1=Qihua |last2=Xie |first2=Shang-Ping |last3=Wang |first3=Dongxiao |last4=Huang |first4=Rui Xin |last5=Chen |first5=Gengxin |last6=Shu |first6=Yeqiang |last7=Shi |first7=Jia-Rui |last8=Liu |first8=Wei |date=2022-04-22 |title=Surface warming–induced global acceleration of upper ocean currents |journal=Science Advances |volume=8 |issue=16 |pages=eabj8394 |doi=10.1126/sciadv.abj8394 |issn=2375-2548 |pmc=9020668 |pmid=35442733|bibcode=2022SciA....8J8394P }}</ref> Ocean currents play a significant role in influencing climate, and shifts in climate, in turn, impact ocean currents.<ref name=":1" /> Over the last century, reconstructed sea surface temperature data reveal that western [[boundary current]]s are heating at double the rate of the global average.<ref>{{Cite journal |last1=Wu |first1=Lixin |last2=Cai |first2=Wenju |last3=Zhang |first3=Liping |last4=Nakamura |first4=Hisashi |last5=Timmermann |first5=Axel |last6=Joyce |first6=Terry |last7=McPhaden |first7=Michael J. |last8=Alexander |first8=Michael |last9=Qiu |first9=Bo |last10=Visbeck |first10=Martin |last11=Chang |first11=Ping |last12=Giese |first12=Benjamin |date=2012-01-29 |title=Enhanced warming over the global subtropical western boundary currents |url=https://www.nature.com/articles/nclimate1353 |journal=Nature Climate Change |volume=2 |issue=3 |pages=161–166 |doi=10.1038/nclimate1353 |bibcode=2012NatCC...2..161W |issn=1758-6798|hdl=1912/5125 |hdl-access=free }}</ref> These observations indicate that the western boundary currents are likely intensifying due to this change in temperature, and may continue to grow stronger in the near future.<ref name=":1" /> Studies investigating international ocean current patterns have also suspected that anthropogenic [[climate change]] has accelerated upper ocean currents by 77%.<ref name=":2" /> Faster upper ocean currents are often associated with increased vertical [[Ocean stratification|stratification]], as well as faster and stronger zonal currents.<ref name=":2" />
-In addition to water surface temperatures, the wind systems are a crucial determinant of ocean currents.<ref>{{Cite journal |last=Constantin |first=Adrian |date=2021-01-02 |title=Frictional effects in wind-driven ocean currents |journal=Geophysical & Astrophysical Fluid Dynamics |volume=115 |issue=1 |pages=1–14 |doi=10.1080/03091929.2020.1748614 |issn=0309-1929|doi-access=free |bibcode=2021GApFD.115....1C }}</ref> Wind wave systems influence oceanic heat exchange, the condition of the sea surface, and can alter ocean currents.<ref name=":3">{{Cite journal |last1=Dobrynin |first1=Mikhail |last2=Murawski |first2=Jens |last3=Baehr |first3=Johanna |last4=Ilyina |first4=Tatiana |date=2015-02-15 |title=Detection and Attribution of Climate Change Signal in Ocean Wind Waves |url=https://journals.ametsoc.org/view/journals/clim/28/4/jcli-d-13-00664.1.xml |journal=Journal of Climate |volume=28 |issue=4 |pages=1578–1591 |doi=10.1175/JCLI-D-13-00664.1 |bibcode=2015JCli...28.1578D |issn=0894-8755}}</ref> In the North Atlantic, equatorial Pacific, and Southern Ocean, increased wind speeds as well as significant wave heights have been attributed to climate change and natural processes combined.<ref name=":3" /> In the [[East Australian Current]], global warming has also been accredited to increased wind stress curls, which intensify these currents, and may even indirectly increase sea levels, due to the additional warming created by stronger currents.<ref>{{Cite journal |last1=Cai |first1=W. |last2=Shi |first2=G. |last3=Cowan |first3=T. |last4=Bi |first4=D. |last5=Ribbe |first5=J. |date=2005-12-10 |title=The response of the Southern Annular Mode, the East Australian Current, and the southern mid-latitude ocean circulation to global warming |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2005GL024701 |journal=Geophysical Research Letters |volume=32 |issue=23 |doi=10.1029/2005GL024701 |bibcode=2005GeoRL..3223706C |issn=0094-8276}}</ref>
-As ocean circulation changes due to climate, typical distribution patterns are also changing. The [[Biological dispersal|dispersal patterns]] of marine organisms depend on oceanographic conditions, which as a result, influence the biological composition of oceans.<ref name=":0" /> Due to the patchiness of the natural ecological world, dispersal is a species survival mechanism for various organisms.<ref>{{Cite journal |last=Kininmonth |first=Stuart |date=2011-04-11 |title=Dispersal connectivity and reserve selection for marine conservation |url=https://www.sciencedirect.com/science/article/abs/pii/S0304380011000445 |journal=Ecological Modelling |volume=222 |issue=7 |pages=1272–1282|doi=10.1016/j.ecolmodel.2011.01.012 |bibcode=2011EcMod.222.1272K }}</ref> With strengthened boundary currents moving toward the poles, it is expected that some marine species will be redirected to the poles and greater depths.<ref name=":0" /><ref>{{Cite journal |last1=Vergés |first1=Adriana |last2=Steinberg |first2=Peter D. |last3=Hay |first3=Mark E. |last4=Poore |first4=Alistair G. B. |last5=Campbell |first5=Alexandra H. |last6=Ballesteros |first6=Enric |last7=Heck |first7=Kenneth L. |last8=Booth |first8=David J. |last9=Coleman |first9=Melinda A. |last10=Feary |first10=David A. |last11=Figueira |first11=Will |last12=Langlois |first12=Tim |last13=Marzinelli |first13=Ezequiel M. |last14=Mizerek |first14=Toni |last15=Mumby |first15=Peter J. |date=2014-08-22 |title=The tropicalization of temperate marine ecosystems: climate-mediated changes in herbivory and community phase shifts |journal=Proceedings of the Royal Society B: Biological Sciences |volume=281 |issue=1789 |pages=20140846 |doi=10.1098/rspb.2014.0846 |issn=0962-8452 |pmc=4100510 |pmid=25009065}}</ref> The strengthening or weakening of typical dispersal pathways by increased temperatures are expected to not only impact the survival of native marine species due to inability to replenish their [[Metapopulation|meta populations]] but also may increase the prevalence of [[invasive species]].<ref name=":0" /> In Japanese corals and macroalgae, the unusual dispersal pattern of organisms toward the poles may destabilize native species.<ref>{{Cite journal |last1=Kumagai |first1=Naoki H. |last2=García Molinos |first2=Jorge |last3=Yamano |first3=Hiroya |last4=Takao |first4=Shintaro |last5=Fujii |first5=Masahiko |last6=Yamanaka |first6=Yasuhiro |date=2018-09-04 |title=Ocean currents and herbivory drive macroalgae-to-coral community shift under climate warming |journal=Proceedings of the National Academy of Sciences |volume=115 |issue=36 |pages=8990–8995 |doi=10.1073/pnas.1716826115 |doi-access=free |issn=0027-8424 |pmc=6130349 |pmid=30126981|bibcode=2018PNAS..115.8990K }}</ref>
-== Economic importance ==
-Knowledge of  surface ocean currents is essential in reducing costs of shipping, since traveling with them reduces fuel costs. In the wind powered [[Sailing ship|sailing-ship]] era, knowledge of wind patterns and ocean currents was even more essential. Using ocean currents to help their ships into harbor and using currents such as the gulf stream to get back home.<ref>{{Cite web |title=Atlantic Ocean - Exploration, Currents, Marine Life {{!}} Britannica |url=https://www.britannica.com/place/Atlantic-Ocean/Study-and-exploration |access-date=2024-04-20 |website=www.britannica.com }}</ref> The lack of understanding of ocean currents during that time period is hypothesized to be one of the contributing factors to exploration failure. The gulf stream and the Canary current keep western European countries warmer and less variable, while at the same latitude North America's weather was colder.<ref>{{Cite web |last=US Department of Commerce |first=National Oceanic and Atmospheric Administration |title=Boundary Currents - Currents: NOAA's National Ocean Service Education |url=https://oceanservice.noaa.gov/education/tutorial_currents/04currents3.html#:~:text=The%20Gulf%20Stream%20is%20a,current%20is%20the%20Gulf%20Stream |access-date=2024-04-20 |website=oceanservice.noaa.gov }}</ref>  A good example of this is the [[Agulhas Current]] (down along eastern Africa), which long prevented sailors from reaching India.
-In recent times, around-the-world sailing competitors make good use of surface currents to build and maintain speed.
-Ocean currents can also be used for [[Marine current power|marine power generation]], with areas of Japan, Florida and Hawaii being considered for test projects. The utilization of currents today can still impact global trade, it can reduce the cost and emissions of shipping vessels.<ref>{{Cite journal |last1=Chang |first1=Yu-Chia |last2=Tseng |first2=Ruo-Shan |last3=Chen |first3=Guan-Yu |last4=Chu |first4=Peter C. |last5=Shen |first5=Yung-Ting |date=November 2013 |title=Ship Routing Utilizing Strong Ocean Currents |url=https://www.cambridge.org/core/journals/journal-of-navigation/article/abs/ship-routing-utilizing-strong-ocean-currents/02039ECA1A45DCDD0B7935C94F79CBB9 |journal=The Journal of Navigation |volume=66 |issue=6 |pages=825–835 |doi=10.1017/S0373463313000441 |issn=0373-4633}}</ref> Ocean currents can also impact the fishing industry, examples of this include the [[Tsugaru current|Tsugaru]], [[Oyashio Current|Oyashio]] and [[Kuroshio Current|Kuroshio]] currents all of which influence the western North Pacific temperature, which has been shown to be a habitat predictor for the [[Skipjack tuna]].<ref>{{Cite journal |last1=Ramesh |first1=Nandini |last2=Rising |first2=James A. |last3=Oremus |first3=Kimberly L. |date=2019-06-21 |title=The small world of global marine fisheries: The cross-boundary consequences of larval dispersal |url=https://www.science.org/doi/10.1126/science.aav3409 |journal=Science |volume=364 |issue=6446 |pages=1192–1196 |doi=10.1126/science.aav3409 |bibcode=2019Sci...364.1192R |issn=0036-8075}}</ref> It has also been shown that it is not just local currents that can affect a country's economy, but neighboring currents can influence the viability of local fishing industries.<ref>{{Cite journal |last=Talley |first=Lynne D. |date=April 1, 1995 |title=North Pacific Intermediate Water in the Kuroshio/Oyashio Mixed Water Region |url=https://journals-ametsoc-org.ezp1.lib.umn.edu/view/journals/phoc/25/4/1520-0485_1995_025_0475_npiwit_2_0_co_2.xml |journal=American Meteorological Society |volume=25 |issue=4 |pages=475–501 |doi=10.1175/1520-0485(1995)025<0475:NPIWIT>2.0.CO;2 |bibcode=1995JPO....25..475T |via=AMS Publications|doi-access=free }}</ref>
 == See also ==

v t e Physical oceanography
Waves	Airy wave theory Ballantine scale Benjamin–Feir instability Boussinesq approximation Breaking wave Clapotis Cnoidal wave Cross sea Dispersion Edge wave Equatorial waves Gravity wave Green's law Infragravity wave Internal wave Iribarren number Kelvin wave Kinematic wave Longshore drift Luke's variational principle Mild-slope equation Radiation stress Rogue wave Rossby wave Rossby-gravity waves Sea state Seiche Significant wave height Soliton Stokes drift Stokes problem Stokes wave Swell Trochoidal wave Tsunami megatsunami Undertow Ursell number Wave action Wave base Wave height Wave nonlinearity Wave power Wave radar Wave setup Wave shoaling Wave turbulence Wave–current interaction Waves and shallow water one-dimensional Saint-Venant equations shallow water equations Wind fetch Wind setup Wind wave model
Circulation	Atmospheric circulation Baroclinity Boundary current Coriolis force Coriolis–Stokes force Craik–Leibovich vortex force Downwelling Eddy Ekman layer Ekman spiral Ekman transport El Niño–Southern Oscillation General circulation model Geochemical Ocean Sections Study Geostrophic current Global Ocean Data Analysis Project Gulf Stream Humboldt Current Hydrothermal circulation Langmuir circulation Longshore drift Loop Current Modular Ocean Model Ocean current Ocean dynamical thermostat Ocean dynamics Ocean gyre Overflow Princeton Ocean Model Rip current Subsurface ocean current Sverdrup balance Thermohaline circulation shutdown Upwelling Whirlpool Wind generated current World Ocean Circulation Experiment
Tides	Amphidromic point Earth tide Head of tide Internal tide Lunitidal interval Perigean spring tide Rip tide Rule of twelfths Slack tide Theory of tides Tidal bore Tidal force Tidal power Tidal race Tidal range Tidal resonance Tide gauge Tideline
Landforms	Abyssal fan Abyssal plain Atoll Bathymetric chart Carbonate platform Coastal geography Cold seep Continental margin Continental rise Continental shelf Contourite Guyot Hydrography Knoll Ocean bank Oceanic basin Oceanic plateau Oceanic trench Passive margin Seabed Seamount Submarine canyon Submarine volcano
Plate tectonics	Convergent boundary Divergent boundary Fracture zone Hydrothermal vent Marine geology Mid-ocean ridge Mohorovičić discontinuity Oceanic crust Outer trench swell Ridge push Seafloor spreading Slab pull Slab suction Slab window Subduction Transform fault Vine–Matthews–Morley hypothesis Volcanic arc
Ocean zones	Benthic Deep ocean water Deep sea Littoral Mesopelagic Oceanic Pelagic Photic Surf Swash
Sea level	Deep-ocean Assessment and Reporting of Tsunamis Global Sea Level Observing System North West Shelf Operational Oceanographic System Sea-level curve Sea level drop Sea level rise World Geodetic System
Acoustics	Deep scattering layer Ocean acoustic tomography Sofar bomb SOFAR channel Underwater acoustics
Satellites	Jason-1 OSTM/Jason-2 Jason-3
Related	Acidification Argo Benthic lander Color of water DSV Alvin Marginal sea Marine energy Marine pollution Mooring National Oceanographic Data Center Ocean Explorations Observations Reanalysis Ocean surface topography Ocean temperature Ocean thermal energy conversion Oceanography Outline of oceanography Pelagic sediment Sea surface microlayer Sea surface temperature Seawater Science On a Sphere Stratification Thermocline Underwater glider Water column World Ocean Atlas
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