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Encyclopedia > Physical oceanography
World Oceans
World Oceans

Physical oceanography is the study of physical conditions and physical processes within the ocean, especially the motions and physical properties of ocean waters. Image File history File links World11. ... Image File history File links World11. ... Animated map exhibiting the worlds oceanic waters. ...


Physical oceanography is one of several sub-domains into which oceanography is divided; others include biological, chemical and geological oceanographies. Thermohaline circulation Oceanography (from Ocean + Greek γράφειν = write), also called oceanology or marine science, is the branch of Earth Sciences that studies the Earths oceans and seas. ... Marine biology is the scientific study of the plants, animals and other organisms that live in the ocean or any other body of water. ... Chemical oceanography is the study of the behaviour of the chemical elements within the Earths oceans. ... Marine geology involves geophysical, geochemical, sedimentological and paleontological investigations of the ocean floor and coastal margins. ...

Contents

The physical setting

The pioneering oceanographer Matthew Maury said in 1855 "Our planet is invested with two great oceans; one visible, the other invisible; one underfoot, the other overhead; one entirely envelopes it, the other covers about two thirds of its surface." The fundamental role of the oceans in shaping Earth is acknowledged by ecologists, geologists, meteorologists, climatologists, geographers and others interested in the physical world. An Earth without oceans would truly be unrecognizable. Matthew Fontaine Maury Matthew Fontaine Maury (January 14, 1806 – February 1, 1873), USN - American astronomer, astrophysicist, historian, oceanographer, meteorologist, cartographer, author, geologist, educator. ... This article or section does not cite any references or sources. ... This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... Satellite image of Hurricane Hugo with a polar low visible at the top of the image. ... Climatology is the study of climate, scientifically defined as weather conditions averaged over a period of time,[1] and is a branch of the atmospheric sciences. ... Map of the Earth Geography (from the Greek words Geo (γη) or Gaea (γαια), both meaning Earth, and graphein (γραφειν) meaning to describe or to writeor to map) is the study of the earth and its features, inhabitants, and phenomena. ...


Roughly 97% of the planet's water is in its oceans, and the oceans are the source of the vast majority of water vapor that condenses in the atmosphere and falls as rain or snow on the continents (Pinet 1996), (Hamblin 1998). The tremendous heat capacity of the oceans moderates the planet's climate, and its absorption of various gases affects the composition of the atmosphere (Hamblin 1998). The ocean's influence extends even to the composition of volcanic rocks through seafloor metamorphism, as well as to that of volcanic gases and magmas created at subduction zones (Hamblin 1998). It has been suggested that multiple sections of steam be merged into this article or section. ... Rain is a type of precipitation which forms when separate drops of water fall to the Earths surface from clouds. ... Snow is a type of precipitation in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... View of Jupiters active atmosphere, including the Great Red Spot. ... For other uses, see Volcano (disambiguation). ... Metamorphic rock is the result of the transformation of a pre-existing rock type, the protolith, in a process called metamorphism, which means change in form, derived from the Greek words meta, change, and morphe, form. The protolith is subjected to extreme heat (>150 degrees Celsius) and pressure causing profound... Magma is molten rock located beneath the surface of the Earth (or any other terrestrial planet), and which often collects in a magma chamber. ... Categories: Geology stubs | Plate tectonics ...


Vertical and horizontal dimensions

Perspective view of the sea floor of the Atlantic Ocean and the Caribbean Sea. The Lesser Antilles are on the lower left side of the view and Florida is on the upper right. The purple sea floor at the center of the view is the Puerto Rico trench, the deepest part of the Atlantic Ocean and the Caribbean Sea.
Perspective view of the sea floor of the Atlantic Ocean and the Caribbean Sea. The Lesser Antilles are on the lower left side of the view and Florida is on the upper right. The purple sea floor at the center of the view is the Puerto Rico trench, the deepest part of the Atlantic Ocean and the Caribbean Sea.

The oceans are far deeper than the continents are tall; the average elevation of Earth's landmasses is only 840 meters, while the ocean's average depth is 3800 meters (Way, Hypsographic curve). Though this apparent discrepancy is great, for both land and sea, the respective extremes such as mountains and trenches are rare (Pinet 1996). Image File history File linksMetadata Download high resolution version (1500x1076, 330 KB)Perspective view of the sea floor of the Atlantic Ocean and the Caribbean Sea. ... Image File history File linksMetadata Download high resolution version (1500x1076, 330 KB)Perspective view of the sea floor of the Atlantic Ocean and the Caribbean Sea. ... Animated, colour-coded map showing the various continents. ... metre or meter, see meter (disambiguation) The metre is the basic unit of length in the International System of Units. ... metre or meter, see meter (disambiguation) The metre is the basic unit of length in the International System of Units. ... Mount Cook, a mountain in New Zealand A mountain is a landform that extends above the surrounding terrain in a limited area. ... Trench warfare is a form of war in which both opposing armies have static lines of fortifications dug into the ground, facing each other. ...

Area, volume plus mean and maximum depths of oceans (excluding adjacent seas)
Body Area (106km²) Volume (106km³) Mean depth (m) Maximum (m)
Pacific Ocean 165.2 707.6 4282 -10911
Atlantic Ocean 82.4 323.6 3926 -8605
Indian Ocean 73.4 291.0 3963 -8047
Southern Ocean 20.3 -7235
Arctic Ocean 14.1 1038
Caribbean Sea 2.8 -7686

Map of Central America and the Caribbean Caribbean Sea from space (top left). ...

Temperature, salinity and density

Because the vast majority of the world ocean's volume is deep water, the mean temperature of seawater is low; roughly 75% of the ocean's volume has a temperature from 0° - 5° C (Pinet 1996). The same percentage falls in a salinity range between 34-35 ppt (3.4-3.5%) (Pinet 1996). There is still quite a bit of variation, however. Surface temperatures can range from below freezing near the poles to 35°C in restricted tropical seas, while salinity can vary from 10 to 41 ppt (1.0-4.1%) (Marshak 2001).


The vertical structure of the temperaturecan be divided into three basic layers, a surface mixed layer, where gradients are high, a thermocline where gradients are high, and a poorly stratified abyss. The oceanic or limnological mixed layer is the top zone in the ocean or a lake, having variable depth depending on how far the energy from the wind has penetrated into the water. ... The thermocline is a layer within a body of water where the temperature changes rapidly with depth. ...


In terms of temperature, the ocean's layers are highly latitude-dependent; the thermocline is pronounced in the tropics, but nonexistent in polar waters (Marshak 2001). The halocline usually lies near the surface, where evaporation raises salinity in the tropics, or meltwater dilutes it in polar regions (Marshak 2001). These variations of salinity and temperature with depth change the density of the seawater, creating the pycnocline (Pinet 1996). Latitude,usually denoted symbolically by the Greek letter phi, , gives the location of a place on Earth north or south of the equator. ... The thermocline is a layer within a body of water where the temperature changes rapidly with depth. ... A Halocline is a salinity gradient, a change in the concentration of salt dissolved in water. ... A pycnocline is a layer of rapid change in water density with depth. ...


Density

Density-driven thermohaline circulation
Density-driven thermohaline circulation

Also see: Image File history File links Please see the file description page for further information. ... Image File history File links Please see the file description page for further information. ... A simplified summary of the path of the Thermohaline Circulation. ...

Downwelling is the process of accumulation and sinking of higher density material beneath lower density material, such as cold or saline water beneath warmer or fresher water or cold air beneath warm air. ... Hydrothermal circulation in the oceans is the passage of the water through mid-ocean Ridge (MOR) systems. ... An ocean current is any more or less continuous, directed movement of ocean water that flows in one of the Earths oceans. ... Upwelling is an oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-deplete surface water. ...

The general circulation of the ocean

The ultimate energy source for the ocean circulation (and for the atmospheric circulation) is the sun. The amount of sunlight absorbed at the surface varies strongly with latitude, being greater at the equator than at the poles, and this engenders fluid motion in both the atmosphere and ocean that acts to redistribute heat from the equator towards the poles, thereby reducing the temperature gradients that would exist in the absence of fluid motion. Perhaps three quarters of this heat is carried in the atmosphere; the rest is carried in the ocean.


The atmosphere is heated from below, which leads to convection, the largest expression of which is the Hadley circulation. By contrast the ocean is heated from above, which tends to suppress convection. Instead ocean deep water is formed in polar regions where cold salty waters sink in fairly restricted areas. This is the beginning of the thermohaline circulation. The major driving force of atmospheric circulation in the tropical regions is solar heating. ... A simplified summary of the path of the Thermohaline Circulation. ...


Oceanic currents are largely driven by the surface wind stress; hence the large-scale atmospheric circulation is important to understanding the ocean circulation. The Hadley circulation leads to Easterly winds in the tropics and Westerlies in mid-latitudes, which creates an anticyclonic wind stress curl over the subtropical ocean. This leads to slow equatorward flow throughout most of a subtropical ocean basin (the Sverdrup balance). The return flow occurs in an intense, narrow, poleward western boundary current. Like the atmosphere, the ocean is far wider than it is deep, and hence horizontal motion is in general much faster than vertical motion. In the southern hemisphere there is a continuous belt of ocean, and hence the mid-latitude westerlies force the strong Antarctic Circumpolar Current. In the northern hemisphere the land masses prevent this and the ocean circulation is broken into smaller gyres in the Atlantic and Pacific basins. Atmospheric circulation is the large-scale movement of air, and the means (together with the ocean circulation, which is smaller [1]) by which heat is distributed on the surface of the Earth. ... Harald Sverdrup in 1947 proposed a theory of ocean circulation and derived a relationship between the wind forcing (expressed as the curl of the wind stress) and the mass transport of the upper ocean. ... A western boundary current is a warm, deep, narrow, and fast flowing current that occurs on the west side of an ocean basin. ... The Antarctic Circumpolar Current (ACC) is an ocean current that flows from west to east around Antarctica. ...


The Coriolis Effect

Hurricane Isabel east of the Bahamas on 15 September 2003
Hurricane Isabel east of the Bahamas on 15 September 2003

The Coriolis effect results in a deflection of fluid flows (to the right in the northern hemisphere and left in the Southern Hemisphere). Because the distance around the Earth decreases as one moves away from the equator, and because the Earth rotates in a counter clockwise direction, air and water masses are deflected to the east as they move from the equator to the poles, and to the west as they move from the poles to the equator. This has profound effects on the flow of the oceans. In particular it means the flow goes around high and low pressure systems, permitting them to persist for long periods of time. As a result, tiny variations in pressure can produce measurable currents. A slope of one part in one million in sea surface height, for example, will result in a current of 1 cm/s at mid-latitudes. The fact that the Coriolis effect is largest at the poles and weak at the equator results in sharp, relatively steady western boundary currents which are absent on eastern boundaries. Also see secondary circulation effects. Download high resolution version (600x776, 142 KB)Hurricane Isabel east of the Bahamas 2003-09-15. ... Download high resolution version (600x776, 142 KB)Hurricane Isabel east of the Bahamas 2003-09-15. ... Hurricane Isabel was the ninth named storm, the fifth hurricane, the second major hurricane, and the only Category 5 hurricane of the 2003 Atlantic hurricane season. ... is the 258th day of the year (259th in leap years) in the Gregorian calendar. ... Year 2003 (MMIII) was a common year starting on Wednesday (link displays 2003 calendar) of the Gregorian calendar. ... In the inertial frame of reference (upper part of the picture), the black object moves in a straight line. ... A secondary circulation is a circulation induced in a rotating system. ...


The Coriolis effect is also responsible for coastal upwelling as wind-driven currents tend to forced to the right of the winds in the Northern Hemisphere and to the left of the winds in the Southern Hemisphere. When winds blow either equatorward along an eastern ocean boundary or poleward along a western ocean boundary, water is driven away from the coasts (the so called Ekman transport), and denser water rises from below to replace it. Upwelling is an oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-deplete surface water. ... This article or section does not cite any references or sources. ... Closely related to the Ekman spiral, where winds blowing up and down coastal regions cause a seaward flow of surface water (perpendicular to the flow of wind), which creates the upwelling of deep nutrient rich sea water. ...


Ekman Transport

Ekman Transport results in the net transport of surface water 90 degrees to the right of the wind in the Northern Hemisphere, and 90 degrees to the left of the wind in the Southern Hemisphere. As the wind blows across the surface of the ocean, it "grabs" onto a thin layer of the surface water. In turn, that thin sheet of water transfers motion energy to the thin layer of water under it, and so on. However, because of the Coriolis Effect, the direction of travel of the layers of water slowly move farther and farther to the right as they get deeper in the Northern Hemisphere, and to the left in the Southern Hemisphere. In most cases, the very bottom layer of water affected by the wind is at a depth of 100 m - 150 m and is traveling about 180 degrees, completely opposite of the direction that the wind is blowing. Overall, the net transport of water would be 90 degrees from the original direction of the wind.


Langmuir Circulation

Langmuir Circulation results in the rare occurrence of thin, visible stripes on the surface of the ocean parallel to the direction that the wind is blowing. If the wind is blowing with exactly the right amount of force, it can create parallel stripes alternating upwelling and downwelling about 30 m apart. These stripes are created by adjacent ovular water cells (extending to about 6 m deep) alternating rotating clockwise and counterclockwise. In the stripes of downwelling debris accumulates, while in the stripes of upwelling plankton are caught and pushed to the top. If there are many plankton caught in one stripe at once, fish are often attracted to feed on them.


Ocean - atmosphere interface

At the ocean-atmosphere interface, the ocean and atmosphere exchange fluxes of heat, moisture and momentum.

Heat

The important heat terms at the surface are the sensible heat flux, the latent heat flux, the incoming solar radiation and the balance of long-wave (infra red) radiation. In general, the tropical oceans will tend to show a net gain of heat, and the polar oceans a net loss, the result of a net transfer of energy polewards in the oceans.


The oceans' large heat capacity moderates the climate of areas adjacent to the oceans, leading to a maritime climate at such locations. This can be a result of heat storage in summer and release in winter; or of transport of heat from warmer locations: a particularly notable example of this is Western Europe, which is heated at least in part by the north atlantic drift. An oceanic climate (also called marine west coast climate and maritime climate) is the climate typically found along the west coasts at the middle latitudes of all the worlds continents, and in southeastern Australia; similar climates are also found at high elevations within the tropics. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ...

Momentum

Surface winds tend to be of order meters per second; ocean currents of order centimeters per second. Hence from the point of view of the atmosphere, the ocean can be considered effectively stationary; from the point of view of the ocean, the atmosphere imposes a significant wind stress on its surface, and this forces large-scale currents in the ocean.

Moisture

The ocean can gain moisture from rainfall, or lose it through evaporation. Evaporative loss leaves the ocean saltier; the Mediterranean and Persian Gulf for example have strong evaporative loss; the resulting plume of dense salty water may be traced through the Straits of Gibraltar into the Atlantic. At one time, it was believed that evaporation/precipitation was a major driver of ocean currents; it is now known to be only a very minor factor.


Planetary waves in the ocean

Kelvin Waves

A Kelvin waves is any progressive wave that is channeled between two boundaries or opposing forces (usually between the Coriolis force and a coastline or the equator). There are two types, coastal and equatorial. Kelvin waves are gravity driven and non-dispersive, meaning that the phase speed of the wave at any one frequency will equal the group speed of the wave energy for all frequencies. This means that Kelvin waves can retain their shape and direction over long periods of time. They are usually created by a sudden shift in the wind, such as the change of the trade winds at the beginning of El Niño.


Coastal Kelvin waves follow shorelines and will always propagate in a counterclockwise direction in the Northern hemisphere (with the shoreline to the right of the direction of travel) and clockwise in the Southern hemishpere.


Equatorial Kelvin waves propagate to the east in the Northern hemisphere and to the west in the Southern hemishpere, using the equator as a guide.


Kelvin waves are known to have very high speeds, typically around 2-3 meters per second. They have wavelengths of thousands of kilometers and amplitudes in the tens of meters.

Rossby Waves

Rossby waves, or planetary waves are huge, slow waves generated in the troposphere by temperature differences between the ocean and the contintents. Their major restoring force is the change in Coriolis force with latitude. Their wave amplitudes are usually in the tens of meters and very large wavelengths. They are usually found at low or mid lattitudes


There are two types of Rossby waves, barotropic and baroclinic. Barotropic Rossby waves have the highest speeds and do not vary vertically. Baroclinic Rossby waves are much slower.


The special identifying feature of Rossby waves is that the phase velocity of each individual wave always has a westward component, but the group velocity can be in any direction. Usually the shorter Rossby waves have an eastward group velocity and the longer ones have a westward group velocity.


Climate variability

December 1997 chart of ocean surface temperature anomaly [°C] during the last strong El Niño

The interaction of ocean circulation, which serves as a type of heat pump, and biological effects such as the concentration of carbon dioxide can result in global climate changes on a time scale of decades. Known climate oscillations resulting from these interactions, include the Pacific decadal oscillation, North Atlantic oscillation, and Arctic oscillation. The oceanic process of thermohaline circulation is a significant component of heat redistribution across the globe, and changes in this circulation can have major impacts upon the climate. Chart of abnormal ocean surface temperatures [ºC] observed in December 1997 during the last strong El Niño (source: National Centers for Environmental Prediction, US). ... Chart of abnormal ocean surface temperatures [ºC] observed in December 1997 during the last strong El Niño (source: National Centers for Environmental Prediction, US). ... In order to meet Wikipedias quality standards, this article requires cleanup. ... Variations in CO2, temperature and dust from the Vostok ice core over the last 400,000 years For current global climate change, see Global warming. ... The Pacific Decadal Oscillation (PDO) is a pattern of Pacific climate variability that shifts phases on at least inter-decadal time scale, usually about 20 to 30 years. ... The North Atlantic oscillation (NAO) is a complex climatic phenomenon in the North Atlantic Ocean (especially associated with fluctuations of climate between Iceland and the Azores). ... The Arctic oscillation (AO) is the dominant pattern of non-seasonal sea-level pressure (SLP) variations north of 20N, and it is characterized by SLP anomalies of one sign in the Arctic and anomalies of opposite sign centered about 37-45N. The North Atlantic oscillation (NAO) is a close relative... A simplified summary of the path of the Thermohaline Circulation. ...


La Niña - El Niño

Main article: El Niño

Chart of ocean surface temperature anomaly [°C] during the last strong El Niño in December 1997 El Niño and La Niña (also written in English as El Nino and La Nina) are major temperature fluctuations in surface waters of the tropical Eastern Pacific Ocean. ...

Antarctic Circumpolar Wave

This is a coupled ocean/atmosphere wave that circles the Southern Ocean about every eight years. Since it is a wave-2 phenomenon (there are two peaks and two troughs in a latitude circle) at each fixed point in space a signal with a period of four years is seen. The wave moves eastward in the direction of the Antarctic Circumpolar Current. The Antarctic Circumpolar Wave is a coupled ocean/atmosphere wave that circles the Southern Ocean in approximately eight years. ... Animated map exhibiting the worlds oceanic waters. ... Layers of Atmosphere - not to scale (NOAA)[3] Earths atmosphere is a layer of gases surrounding the planet Earth and retained by the Earths gravity. ... A wave is a disturbance that propagates through space or spacetime, transferring energy and momentum and sometimes angular momentum. ... On the Earth, a circle of latitude is an imaginary east-west circle that connects all locations with a given latitude. ... Simple harmonic motion is the motion of a simple harmonic oscillator, a motion that is neither driven nor damped. ... The Antarctic Circumpolar Current (ACC) is an ocean current that flows from west to east around Antarctica. ...


Ocean currents

These global thermodynamic forces drive ocean currents: Thermodynamics (Greek: thermos = heat and dynamic = change) is the physics of energy, heat, work, entropy and the spontaneity of processes. ... An ocean current is any more or less continuous, directed movement of ocean water that flows in one of the Earths oceans. ...

The Antarctic Circumpolar Current (ACC) is an ocean current that flows from west to east around Antarctica. ... A simplified summary of the path of the Thermohaline Circulation. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ... The Kuroshio Current is an ocean current found in the western Pacific Ocean off the east coast of Taiwan and flowing northeastward past Japan, where it merges with the easterly drift of the North Pacific Current. ...

Antarctic Circumpolar Current

The ocean body surrounding the Antarctic is currently the only continuous body of water to circumnavigate the globe about the polar axis. It interconnects the Atlantic, Pacific and Indian oceans, and provide an uninterrupted stretch for the prevailing westerly winds to significantly increase wave amplitudes. It is generally accepted that these prevailing winds are primarily responsible for the circumpolar current transport. This current is now thought to vary with time, possibly in an oscillatory manner. Greek ἀνταρκτικός, opposite the arctic) is a continent surrounding the Earths South Pole. ... The Atlantic Ocean forms a component of the all-encompassing World Ocean and is directly linked to the Arctic Ocean, the Pacific Ocean, the Indian Ocean, and the Southern Ocean. ... The Pacific Ocean (from the Latin name Mare Pacificum, peaceful sea, bestowed upon it by the Portuguese explorer Ferdinand Magellan) is the largest of the Earths oceanic subdivisions. ...


Deep ocean currents (abyssal circulation)

In the Norwegian Sea evaporative cooling is predominant, and the sinking water mass, the North Atlantic Deep Water (NADW), fills the basin and spills southwards through crevasses in the submarine sills that connect Greenland, Iceland and Britain. It then flows along the western boundary of the Atlantic with some part of the flow moving eastward along the equator and then poleward into the ocean basins. The NADW is entrained into the Circumpolar Current, and can be traced into the Indian and Pacific basins. Flow from the Arctic Ocean Basin into the Pacific, however, is blocked by the narrow shallows of the Bering Strait. The Norwegian Sea (Norwegian: Norskehavet) is part of the North Atlantic Ocean northwest of Norway, located between the North Sea (i. ... North Atlantic Deep Water The North Atlantic Deep Water is a water mass, buit in the Atlantic Ocean. ... In geology, a sill is a tabular, often horizontal mass of igneous rock that has been intruded laterally between older layers of sedimentary rock, beds of volcanic lava or tuff, or even along the direction of foliation in metamorphic rock. ... Satellite photo of the Bering Strait Photo across the Bering Strait Nautical chart of the Bering Strait The Bering Strait (Russian: ) is a sea strait between Cape Dezhnev, Russia, the easternmost point (169°43 W) of the Asian continent and Cape Prince of Wales, Alaska, the westernmost point (168°05...


Also see marine geology about that explores the geology of the ocean floor including plate tectonics that create deep ocean trenches. Marine geology involves geophysical, geochemical, sedimentological and paleontological investigations of the ocean floor and coastal margins. ... This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... The tectonic plates of the world were mapped in the second half of the 20th century. ...


Western boundary currents

An idealised subtropical ocean basin, forced by an anticyclonic wind stress, acquires a gyre circulation with slow steady flows everywhere except in the region of the western boundary, where a thin fast polewards flow called a western boundary current develops. Flow in the real ocean is more complex, but the Gulf stream, Agulhas and Kuroshio are examples of such currents. They are narrow (approximately 100 km across) and fast (approximately 1.5 m/s). A western boundary current is a warm, deep, narrow, and fast flowing current that occurs on the west side of an ocean basin. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ... The Kuroshio Current is an ocean current found in the western Pacific Ocean off the east coast of Taiwan and flowing northeastward past Japan, where it merges with the easterly drift of the North Pacific Current. ...


Equatorwards western boundary currents occur in tropical and polar locations, e.g. the East Greenland current.

Gulf stream

The Gulf Stream, together with its northern extension, North Atlantic Drift, is a powerful, warm, and swift Atlantic ocean current that originates in the Gulf of Mexico, exits through the Strait of Florida, and follows the eastern coastlines of the United States and Newfoundland to the northeast before crossing the Atlantic Ocean. The North Atlantic drift is a powerful warm ocean current that continues the Gulf Stream northeast. ... Gulf of Mexico in 3D perspective. ...

Kuroshio

The Kuroshio Current is an ocean current found in the western Pacific Ocean off the east coast of Taiwan and flowing northeastward past Japan, where it merges with the easterly drift of the North Pacific Current. It is analogous to the Gulf Stream in the Atlantic Ocean, transporting warm, tropical water northward towards the polar region. The Kuroshio Current is an ocean current found in the western Pacific Ocean off the east coast of Taiwan and flowing northeastward past Japan, where it merges with the easterly drift of the North Pacific Current. ... The North Pacific Current The North Pacific Current (sometimes referred to as the North Pacific Drift) is a slow warm water current that flows west-to-east between 40 and 50 degrees north in the Pacific Ocean. ...


Oceanic heat flux and the climate connection

Heat storage

Sea level change

Main article: Sea level rise

Tide gauges and satellite altimetry suggest an increase in sea level of 1.5-3 mm/yr over the past 100 years. Sea level measurements from 23 long tide gauge records in geologically stable environments show a rise of around 20 centimeters per century (2 mm/year). ...


The IPCC predicts that by 2100, global warming will lead to a sea level rise of 110 to 880 mm. IPCC is science authority for the UNFCCC The Intergovernmental Panel on Climate Change (IPCC) was established in 1988 by two United Nations organizations, the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) to assess the risk of human-induced climate change. The Panel is open to all... Global mean surface temperatures 1850 to 2006 Mean surface temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming is the observed increase in the average temperature of the Earths atmosphere and oceans in recent decades and the projected...


Rapid variations in the ocean

Ocean tides

Main article: Tides

The rise and fall of the oceans due to tidal effects is a key influence upon the coastal areas. Ocean tides on the planet Earth are created by the gravitational effects of the Sun and Moon. The tides produced by these two bodies are roughly comparable in magnitude, but the orbital motion of the Moon results in tidal patterns that vary over the course of a month. This article is about tides in the ocean. ... The Sun (Latin: Sol) is the star at the center of the Solar System. ... Apparent magnitude: up to -12. ...


The ebb and flow of the tides produce a cyclical current along the coast, and the strength of this current can be quite dramatic along narrow estuaries. Incoming tides can also produce a tidal bore along a river or narrow bay as the water flow against the current results in a wave on the surface. The tidal bore in Upper Cook Inlet, Alaska A tidal bore (or just bore, or eagre) is a tidal phenomenon in which the leading edge of the incoming tide forms a wave (or waves) of water that travel up a river or narrow bay against the direction of the current. ...


Tide and Current (Wyban 1992) clearly illustrates the impact of these natural cycles on the lifestyle and livlihood of Native Hawaiians tending coastal fishponds. Aia ke ola ka hana meaning . . . Life is in labor. Native Hawaiians (in Hawaiian, kānaka ōiwi or kānaka maoli) are the Polynesian peoples of the Hawaiian Islands who trace their ancestry back to Marquesan and possibly Tahitian settlers (starting circa AD 400), before the arrival of British explorer Captain James Cook in 1778. ...

The Bay of Fundy is a bay located on the Atlantic coast of North America, on the northeast end of the Gulf of Maine between the provinces of New Brunswick and Nova Scotia.
The Bay of Fundy is a bay located on the Atlantic coast of North America, on the northeast end of the Gulf of Maine between the provinces of New Brunswick and Nova Scotia.

Tidal resonance occurs in the Bay of Fundy since the time it takes for a large wave to travel from the mouth of the bay to the opposite end, then reflect and travel back to the mouth of the bay coincides with the timing between this repeating wave that is also reinforced by the tidal rhythm producing the world's highest tides. Bay of Fundy © 2004 Matthew Trump based on NASA image in public domain File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Bay of Fundy © 2004 Matthew Trump based on NASA image in public domain File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... The bay at San Sebastián, Spain A headland is an area of land adjacent to water on three sides. ... The Atlantic Ocean forms a component of the all-encompassing World Ocean and is directly linked to the Arctic Ocean, the Pacific Ocean, the Indian Ocean, and the Southern Ocean. ... North America North America is a continent[1] in the Earths northern hemisphere and (chiefly) western hemisphere. ... Gulf of Maine The Gulf of Maine is a large gulf of the Atlantic Ocean on the northeastern coast of North America. ... Canada consists of ten provinces and three territories. ... Motto: Spem reduxit (Hope restored) Capital Fredericton Largest city Saint John Official languages English, French (the only constitutionally bilingual province in the country) Government - Lieutenant-Governor Herménégilde Chiasson - Premier Shawn Graham (Liberal) Federal representation in Canadian Parliament - House seats 10 - Senate seats 10 Confederation July 1, 1867 (1st... Motto: Munit Haec et Altera Vincit(Latin) One defends and the other conquers Capital Halifax Largest city Halifax Regional Municipality Official languages English Government - Lieutenant-Governor Mayann E. Francis - Premier Rodney MacDonald (PC) Federal representation in Canadian Parliament - House seats 11 - Senate seats 10 Confederation July 1, 1867 (1st) Area... The Bay of Fundy (French: ) is a bay located on the Atlantic coast of North America, on the northeast end of the Gulf of Maine between the Canadian provinces of New Brunswick and Nova Scotia, with a small portion touching the U.S. state of Maine. ... A wave is a disturbance that propagates through space or spacetime, transferring energy and momentum and sometimes angular momentum. ... In geography, a bay or gulf is a collection of water that is surrounded by land on three sides. ...


Tsunamis

Main article: Tsunami

A series of surface waves can be generated due to large-scale displacement of the ocean water. These can be caused sub-marine land slips, seafloor deformations due to earthquakes, or the impact of a large meteorite. The tsunami that struck Malé in the Maldives on December 26, 2004. ... An earthquake is a result from the sudden release of stored energy in the Earths crust that creates seismic waves. ... Willamette Meteorite A meteorite is a natural object originating in outer space that survives an impact with the Earths surface without being destroyed. ...


The waves can travel with a velocity of up to several hundred km/hour across the ocean surface, but in mid-ocean they are barely detectable with wavelengths spanning hundreds of kilometers. The wavelength is the distance between repeating units of a wave pattern. ...


Tsunamis, originally called tidal waves, were renamed because they are not related to the tides. They are regarded as shallow-water waves, or waves in water with a depth less than 1/20 their wavelength. Tsunamis have very large periods, high speeds, and great wave heights.


The primary impact of these waves is along the coastal shoreline, as large amounts of ocean water are cyclically propelled inland and then drawn out to sea. This can result in significant modifications to the coastline regions where the waves strike with sufficient energy.


References

  • Gill, Adrian E. (1982) Atmosphere-Ocean Dynamics, Academic Press, ISBN 978-0-12-283522-3.
  • Hamblin, W. Kenneth and Eric H. Christiansen (1998)
    Earth's Dynamic Systems, 8th ed., Upper Saddle River: Prentice-Hall ISBN 0-13-018371-7 (8th ed.)
  • Marshak, Stephen. (2001) Earth: Portrait of a Planet, New York: W.W. Norton & Company, ISBN 0-393-97423-5
  • Maury, Matthew F. (1855) The Physical Geography of the Seas and Its Meteorology.
  • Pinet, Paul R. (1996) Invitation to Oceanography, St. Paul, MN: West Publishing Co., ISBN 0-7637-2136-0 (3rd ed.)
  • Way, John H., Hypsographic curve, http://www.lhup.edu/jway/101/101.sg/hypsographic_curve.htm Accessed 10 January 2006

January 10 is the 10th day of the year in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday (link displays full 2006 calendar) of the Gregorian calendar. ... Workers harvest catfish from the Delta Pride Catfish farms in Mississippi Aquaculture is the cultivation of the natural produce of water (fish, shellfish, algae and other aquatic organisms). ... This article is about the University of Hawaii system. ...

See also

Thermohaline circulation Oceanography (from Ocean + Greek γράφειν = write), also called oceanology or marine science, is the branch of Earth Sciences that studies the Earths oceans and seas. ... Animated map exhibiting the worlds oceanic waters. ... Composite satellite image of the Mediterranean Sea. ... A marginal sea is a part of ocean partially enclosed by land such as islands, archipelagos, or peninsulas. ... Variations in CO2, temperature and dust from the Vostok ice core over the last 400,000 years For current global climate change, see Global warming. ... Global Sea Level Observing System (GLOSS) is a Intergovernmental Oceanographic Commissions program whose purpose is to measure the sea level globally for long term climate change studies. ...

External links


  Results from FactBites:
 
Physical oceanography - Wikipedia, the free encyclopedia (2203 words)
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Physical oceanographic research conducted by OSU faculty includes the development of specialized instrumentation, deployment and retrieval of these instruments at sea and processing of the data collected by the instruments.
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