|
Undersea Overflow
In oceanography, an overflow is a type of deep-water ocean current, circulation in which denser water flows into an adjacent Oceanic basin, basin beneath lighter water. This process is significant in thermohaline circulation, contributing to the global ocean's deep water mass formation. Overflows influence global climate by transporting heat and salt, impacting sea levels, and affecting marine ecosystems. Overflows are driven by differences in water density, usually due to variations in Ocean_temperature, temperature and Ocean#Salinity, salinity. A classic example is the Denmark Strait overflow, where cold, dense water from the Nordic Seas flows into the North Atlantic Ocean. References Oceanography {{ocean-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanography
Oceanography (), also known as oceanology, sea science, ocean science, and marine science, is the scientific study of the ocean, including its physics, chemistry, biology, and geology. It is an Earth science, which covers a wide range of topics, including ocean currents, waves, and geophysical fluid dynamics; fluxes of various chemical substances and physical properties within the ocean and across its boundaries; ecosystem dynamics; and plate tectonics and seabed geology. Oceanographers draw upon a wide range of disciplines to deepen their understanding of the world’s oceans, incorporating insights from astronomy, biology, chemistry, geography, geology, hydrology, meteorology and physics. History Early history Humans first acquired knowledge of the waves and currents of the seas and oceans in pre-historic times. Observations on tides were recorded by Aristotle and Strabo in 384–322 BC. Early exploration of the oceans was primarily for cartography and mainly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Current
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. 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 temper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Basin
In hydrology, an oceanic basin (or ocean basin) is anywhere on Earth that is covered by seawater. Geologically, most of the ocean basins are large Structural basin, geologic basins that are below sea level. Most commonly the ocean is divided into basins following the continents distribution: the Atlantic Ocean, North and South Atlantic (together approximately 75 million km2/ 29 million mi2), Pacific Ocean, North and South Pacific (together approximately 155 million km2/ 59 million mi2), Indian Ocean (68 million km2/ 26 million mi2) and Arctic Ocean (14 million km2/ 5.4 million mi2). Also recognized is the Southern Ocean (20 million km2/ 7 million mi2). All ocean basins collectively cover 71% of the Earth's surface, and together they contain almost 97% of all water on the planet. They have an average depth of almost 4 km (about 2.5 miles). Definitions of boundaries Boundaries based on continents ''"Limits of Oceans and Seas"'',International Hydrographic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermohaline Circulation
Thermohaline circulation (THC) is a part of the large-scale Ocean current, ocean circulation driven by global density gradients formed by surface heat and freshwater fluxes. The name ''thermohaline'' is derived from ''wikt:thermo-, thermo-'', referring to temperature, and ', referring to salinity, salt content—factors which together determine the Water (molecule)#Density of saltwater and ice, 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 and sinking en-route to higher latitudes - eventually becoming part of the North Atlantic Deep Water - before flowing into the ocean basins. While the bulk of thermohaline water upwelling, upwells in the Southern Ocean, the oldest waters (with a transit time of approximately 1000 years) upwell in the North Pacific; extensive mixing takes place between the ocean basins, reducing the difference in their densities, forming the Worl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Water Mass
An oceanographic water mass is an identifiable body of water with a common formation history which has physical properties distinct from surrounding water. Properties include temperature, salinity, chemical - isotopic ratios, and other physical quantities which are conservative flow tracers. Water mass is also identified by its non-conservative flow tracers such as silicate, nitrate, oxygen, and phosphate. Water masses are generally distinguished not only by their respective tracers but also by their location in the Worlds' oceans. Water masses are also distinguished by their vertical position so that there are surface water masses, intermediate water masses and deep water masses. Global water masses Common water masses in the world ocean are: * Antarctic Bottom Water (AABW): Antarctic Bottom Water is a very important water mass. Antarctic Bottom Water is the left over part when sea ice is being made. It is very cold but, not quite freezing so the water moves down and along t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Climate
Climate is the long-term weather pattern in a region, typically averaged over 30 years. More rigorously, it is the mean and Statistical dispersion, variability of Meteorology, meteorological variables over a time spanning from months to millions of years. Some of the Meteorology, meteorological variables that are commonly measured are temperature, humidity, atmospheric pressure, wind, and precipitation. In a broader sense, climate is the state of the components of the climate system, including the atmosphere, hydrosphere, cryosphere, lithosphere and biosphere and the interactions between them. The climate of a location is affected by its latitude, longitude, terrain, altitude, land use and nearby body of water, water bodies and their currents. Climates can be Climate classification, classified according to the average and typical variables, most commonly temperature and precipitation. The most widely used classification scheme is the Köppen climate classification. The Thornth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt
In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as rock salt or halite. Salt is essential for life in general (being the source of the essential dietary minerals sodium and chlorine), and saltiness is one of the basic human tastes. Salt is one of the oldest and most ubiquitous food seasonings, and is known to uniformly improve the taste perception of food. Salting, brining, and pickling are ancient and important methods of food preservation. Some of the earliest evidence of salt processing dates to around 6000 BC, when people living in the area of present-day Romania boiled spring water to extract salts; a salt works in China dates to approximately the same period. Salt was prized by the ancient Hebrews, Greeks, Romans, Byzantines, Hittites, Egyptians, and Indians. Salt became a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Level
Mean sea level (MSL, often shortened to sea level) is an mean, average surface level of one or more among Earth's coastal Body of water, bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised geodetic datumthat is used, for example, as a chart datum in cartography and Navigation, marine navigation, or, in aviation, as the standard sea level at which atmospheric pressure is measured to Calibration, calibrate altitude and, consequently, aircraft flight levels. A common and relatively straightforward mean sea-level standard is instead a long-term average of tide gauge readings at a particular reference location. The term ''above sea level'' generally refers to the height above mean sea level (AMSL). The term APSL means above present sea level, comparing sea levels in the past with the level today. Earth's radius at sea level is 6,378.137 km (3,963.191 mi) at the equator. It is 6,356.752 km (3,94 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Ecosystems
Marine ecosystems are the largest of Earth's aquatic ecosystems and exist in waters that have a high salt content. These systems contrast with freshwater ecosystems, which have a lower salt content. Marine waters cover more than 70% of the surface of the Earth and account for more than 97% of Earth's water supply and 90% of habitable space on Earth. Seawater has an average salinity of 35 parts per thousand of water. Actual salinity varies among different marine ecosystems. Marine ecosystems can be divided into many zones depending upon water depth and shoreline features. The oceanic zone is the vast open part of the ocean where animals such as whales, sharks, and tuna live. The benthic zone consists of substrates below water where many invertebrates live. The intertidal zone is the area between high and low tides. Other near-shore (neritic) zones can include mudflats, seagrass meadows, mangroves, rocky intertidal systems, salt marshes, coral reefs, kelp forests and lagoo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Temperature
The ocean temperature plays a crucial role in the global climate system, ocean currents and for marine habitats. It varies depending on depth, geographical location and season. Not only does the temperature differ in seawater, so does the salinity. Warm surface water is generally saltier than the cooler deep or polar waters. In polar regions, the upper layers of ocean water are cold and fresh. Deep ocean water is cold, salty water found deep below the surface of Earth's oceans. This water has a uniform temperature of around 0-3°C. The ocean temperature also depends on the amount of solar radiation falling on its surface. In the tropics, with the Sun nearly overhead, the temperature of the surface layers can rise to over . Near the poles the temperature in equilibrium with the sea ice is about . There is a continuous large-scale circulation of water in the oceans. One part of it is the thermohaline circulation (THC). It is driven by global density gradients created by su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean
The ocean is the body of salt water that covers approximately 70.8% of Earth. The ocean is conventionally divided into large bodies of water, which are also referred to as ''oceans'' (the Pacific, Atlantic, Indian Ocean, Indian, Southern Ocean, Antarctic/Southern, and Arctic Ocean),"Ocean." ''Merriam-Webster.com Dictionary'', Merriam-Webster, https://www.merriam-webster.com/dictionary/ocean . Accessed March 14, 2021. and are themselves mostly divided into seas, gulfs and Lists of bodies of water#Seawater bodies, subsequent bodies of water. The ocean contains 97% of Water distribution on Earth, Earth's water and is the primary component of Earth's hydrosphere, acting as a huge Ocean heat content, reservoir of heat for Earth's energy budget, as well as for its carbon cycle and water cycl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denmark Strait Overflow
The Denmark Strait overflow ( Danish: ''Grønlandspumpen''; Norwegian: ''Grønlandspumpa'', meaning "the Greenland pump") is an undersea overflow located in the Denmark Strait between Greenland and Iceland. The overflow transports around of water per second, greatly eclipsing the discharge of the Amazon River into the Atlantic Ocean and the flow rate of the former Guaíra Falls. The descending column of water is approximately wide and thick and descends over a length of around . It is formed by the density difference of the water masses either side of the Denmark Strait; the southward-flowing water originating from the Nordic Seas is colder and consequently more dense than the Irminger Sea to the south of the strait. At the Greenland–Iceland Risean elevated ridge forming the overflow's apexthe colder water cascades along the seafloor to a depth of around . Due to the Coriolis effect, the downward flow of water is deflected to the right, resulting in the descending water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
