751 articles
Continental shelf
A continental shelf is the submerged, gently sloping edge of a continent, extending from the shoreline to the shelf break at roughly 100 to 200 meters depth.
Convective mixing
Convective mixing is the vertical mixing of a fluid driven by buoyancy, and in lakes it is often the dominant driver of mixing and stratification.
Copernicus Marine Environment Monitoring Service
The Copernicus Marine Environment Monitoring Service, commonly called the Copernicus Marine Service, is the European Union's marine Earth observation service, launched in 2014 and implemented by Mercator Ocean International.
Copernicus Marine Service
The Copernicus Marine Service, also called the Copernicus Marine Environment Monitoring Service, is the European Union's operational ocean monitoring and forecasting service, launched in 2014.
Cosmic-ray neutron sensing
Cosmic-ray neutron sensing (CRNS) is a non-invasive ground-based method that measures soil moisture by counting low-energy neutrons from cosmic rays, with a footprint of hundreds of meters demonstrated in 2008.
Critical load
A critical load is the estimated deposition of a pollutant, most often acidifying sulfur and nitrogen compounds, below which significant harmful effects on a sensitive ecosystem do not occur.
CTD (instrument)
A CTD (conductivity, temperature, depth) is the standard oceanographic instrument for profiling seawater, lowering conductivity, temperature, and pressure sensors from a research vessel to derive salinity and depth.
Cultural eutrophication
Cultural eutrophication is the human-caused acceleration of eutrophication, the over-enrichment of waters with nitrogen and phosphorus from sewage, fertilizers, and detergents, driving algal blooms and oxygen depletion.
Cumbre Vieja tsunami hazard
The Cumbre Vieja tsunami hazard is the possibility that a large collapse of the Cumbre Vieja volcano's western flank on La Palma would generate an Atlantic-crossing tsunami.
Current meter
A current meter is an instrument for measuring the velocity of water at a point in an open channel, used to compute river discharge by the velocity-area method.
Curve number method
The curve number method is an empirical hydrological technique that estimates direct runoff depth from storm rainfall on a watershed using a single parameter, the curve number.
Cylindrospermopsin
Cylindrospermopsin is an alkaloid toxin produced by freshwater cyanobacteria that inhibits protein synthesis, damaging the liver and kidneys. First isolated in 1992, it was the likely cause of a 1979 mass poisoning on Palm Island, Australia.
Daphnia magna
Daphnia magna, commonly called the water flea, is a small freshwater planktonic crustacean living in ponds and lakes across Europe and North America, and a standard test organism in aquatic ecotoxicology.
Daphnia pulex
Daphnia pulex, commonly called the water flea, is a widespread freshwater crustacean that grazes algae in lakes and ponds and was the first crustacean to have its genome sequenced.
Darcy's law
Darcy's law is an empirical law of groundwater flow stating that flow through a porous medium is proportional to the hydraulic gradient, published by Henry Darcy in 1856.
Dead Sea (ים המלח)
The Dead Sea (ים המלח) is a hypersaline terminal lake in the Jordan Rift Valley between Jordan and Israel, about ten times saltier than the ocean.
Dead storage
Dead storage is the volume of reservoir water below the lowest outlet that cannot be drained by gravity, traditionally sized to hold decades of sediment.
Decca Navigator
The Decca Navigator System was a British hyperbolic radio-navigation system, the primary coastal positioning system for world shipping from the late 1940s until GPS displaced it in the 1990s.
Deep Argo
Deep Argo is an expansion of the international Argo program in which profiling floats measure temperature and salinity from the ocean surface to the sea floor every 10 days.
Deep sea
Deep sea: ocean below about 200 m where light fades; also called the aphotic, twilight, midnight, abyssal, and hadal zones. Cold (~4°C), high pressure, food-poor; explored by bathysphere, Trieste, and DEEPSEA CHALLENGER; targeted for seabed mining.
Deep Sea Drilling Project
The Deep Sea Drilling Project was a US-led scientific ocean drilling program run from Scripps Institution of Oceanography that used the drillship Glomar Challenger to core the deep seafloor from 1968 to 1983.
Deep Sea Warrior (AUV)
The Deep Sea Warrior (Shenhai Yongshi) is China's second deep-sea manned submersible, a 4,500-meter-class crewed vehicle delivered in 2017 that reached 4,534 meters on its first dive test.
Deep-ocean Assessment and Reporting of Tsunamis
Deep-ocean Assessment and Reporting of Tsunamis (DART) is a NOAA tsunami monitoring system pairing seafloor pressure recorders with moored surface buoys, expanded to 39 US stations in 2008.
Deep-submergence vehicle
A deep-submergence vehicle (DSV), also called a human-occupied vehicle when crewed, is a submersible launched from a support ship to work at great ocean depths.
Deepsea Challenger
Deepsea Challenger, also known as DCV 1, is a one-person full-ocean-depth submersible built in Sydney, Australia, and piloted by James Cameron to Challenger Deep on March 26, 2012.
Delft-FEWS
Delft-FEWS, short for Flood Early Warning System, is a platform by the Dutch institute Deltares that integrates data and models for operational flood forecasting, introduced in 2002.
Delft3D
Delft3D is a software suite simulating hydrodynamics, sediment transport, waves, and water quality in coastal, estuarine, and river waters, developed by WL | Delft Hydraulics.
Depth sounding
Depth sounding is the measurement of water depth, historically by weighted lead line and today mostly by timing sound or laser pulses from the seafloor.
Destratification
Destratification is the artificial mixing of a thermally stratified lake or reservoir, usually by injecting compressed air, to make temperature and dissolved oxygen roughly uniform throughout.
Devil's Throat, Iguazu Falls
The Devil's Throat (Spanish: Garganta del Diablo; Portuguese: Garganta do Diabo) is the largest and tallest cataract of Iguazu Falls, where the Iguazu River plunges about 80 meters into a U-shaped chasm on the Argentina–Brazil border.