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Sea breeze
A sea breeze, also known as an onshore breeze, is a thermally driven daytime wind blowing from cool water onto warm land, often triggering coastal showers and thunderstorms.
Sea breeze front
A sea breeze front is the leading edge of a sea breeze, where cool marine air undercuts warmer land air, often bringing showers and a sharp temperature drop.
Sea foam
Sea foam, also called ocean foam, is a mass of air bubbles in seawater stabilized by organic molecules and whipped up by wind and breaking waves.
Sea ice
Sea ice is frozen ocean water at the sea surface, distinct from land-origin icebergs and glaciers, covering about 25 million square kilometers and influencing global climate.
Sea ice concentration
Sea ice concentration is the percentage of a given ocean area covered by sea ice, measured mainly by satellite passive microwave sensors and used to compute sea ice extent.
Sea ice extent
Sea ice extent is the total ocean area with at least 15 percent ice cover, measured by satellite since 1979 and reported separately for the Arctic and Antarctic.
Sea level
Sea level, also called mean sea level, is the average height of the ocean's surface. It has risen about 3.6 inches since 1993 as oceans warm and land ice melts.
Sea level rise
Sea level rise is the rise in global ocean height, about 8 to 9 inches since 1880, driven by melting land ice and expanding warm seawater.
Sea level rise in Venice
Sea level rise in Venice is the long-term rise of the sea relative to the land, raising floods known as acqua alta and defended by the MOSE barriers.
Sea state
Sea state, also known as state of the sea, is the condition of the ocean surface described by wave height, period, and direction, coded 0 through 9 on the WMO scale.
Sea surface height
Sea surface height (SSH) is the height of the ocean surface above a reference surface, the ellipsoid or the geoid, measured continuously by satellite radar altimetry since 1992.
Sea surface temperature
Sea surface temperature (SST), also called sea temperature, is the temperature of the ocean's uppermost water, measured from ships, buoys, and satellites and classed as an essential climate variable.
Sea-surface microlayer
The sea-surface microlayer is the uppermost 1–1000 µm layer of the ocean, covering about 70% of Earth's surface and controlling gas and pollutant transfer between sea and atmosphere.
Seabed
The seabed, also called the ocean floor or sea floor, is the solid floor of the world ocean, from intertidal flats to hadal trenches deeper than 6,000 m.
Seafloor classification
Seafloor classification assigns areas of the seabed to categories such as sediment type, hardness, or benthic habitat, most often by interpreting sonar backscatter against ground-truth samples.
Seafloor massive sulfide
Seafloor massive sulfide (SMS) deposits are accumulations of metal-bearing sulfide minerals that form at hydrothermal vent sites on the seafloor, chiefly at oceanic spreading ridges, volcanic arcs, and back-arc basins.
Seafloor spreading
Seafloor spreading, also called ocean floor spreading, is the process at mid-ocean ridges where diverging plates move apart, mantle material wells up, and cooling forms new oceanic crust.
Seaglider
Seaglider is a long-range autonomous underwater vehicle developed at the University of Washington that glides by changing its buoyancy, measuring temperature, salinity, and other water properties for months at sea.
Seasat
Seasat was the first Earth-orbiting satellite designed for remote sensing of the oceans, launched from Vandenberg in June 1978 and lost after 105 days to a power-system failure.
Season
A season is a period of the year with distinct climate and weather patterns. Earth's axial tilt of about 23.4 degrees drives four seasons in the mid-latitudes, spring, summer, fall, and winter.
Seasonal lag
Seasonal lag is the delay between the time of maximum solar input and the time of a location's warmest or coldest temperatures, larger over ocean than land.
Seawater
Seawater, also called marine water, is the salt water of the ocean, typically containing about 35 grams of dissolved salt per liter, mostly sodium and chloride.
SeaWiFS
SeaWiFS, the Sea-viewing Wide Field-of-view Sensor, was an ocean-color satellite instrument aboard OrbView-2, built by Orbital Sciences and launched in 1997, that measured global chlorophyll.
Secchi disk
A Secchi disk is a plain white or black-and-white disk lowered into water until it vanishes, measuring water transparency, named for Pietro Angelo Secchi in 1865.
Secondary migration
Secondary migration is the movement of petroleum after expulsion from its source rock through permeable carrier beds toward a trap, driven by buoyancy and limited by capillary pressure.
SECOR (satellite)
SECOR (Sequential Collation of Range), also designated EGRS, was a United States Army geodetic satellite program of 1964 to 1969 that fixed remote positions by electronic trilateration.
Sediment
Sediment is loose, uncemented rock, mineral, or biological material that settles out of water or air into layers; most ultimately comes to rest in the ocean.
Sediment budget
A sediment budget is an accounting of the sources, storage, and export of sediment in a system such as a watershed, applying conservation of mass.
Sediment bypassing
Sediment bypassing is the transfer of sand from the updrift to the downdrift side of a coastal barrier like a tidal inlet, preventing erosion and channel shoaling.
Sediment connectivity
Sediment connectivity is the degree of linkage controlling sediment fluxes between sources and downstream areas of a catchment, measured with the index of connectivity derived from elevation models.