Science — page 105 of 132

13,110 terms including subtopics (0 terms filed directly here)

Science terms

Saltation The movement of sand or fine sediment by short jumps above a streambed under the influence of a water current too weak to keep it permanently suspended in…
Salvage logging The harvest of dead, dying, damaged or weak trees after a forest fire to prevent the spread of disease or insects and to reduce the risk of high intensity…
SAME (Specific Area Message Encoding) - A tone alert system which allows NOAA Weather Radio receivers equipped with the SAME feature to sound an alert for only…
SAMEX Storm and Mesoscale Ensemble Experiment
Sample error Random variation reflecting the inherent variability within a population being counted.
sampling The process of digitizing analog information to identify relevant information.
sampling frequency The rate at which sensor data is read or sampled.
Sand A rock or mineral fragment of any composition that has a diameter ranging from 0.5 to 2.0 mm. Sand has a gritty feel.
Sand backfill Material which has a particle size which varies from a No. 4 sieve to a No. 200 sieve and is used for refilling an excavation.
Sand boil A sand boil is sand and water that come out onto the ground surface during an earthquake as a result of liquefaction at shallow depth.
Sand dune An elongated mound (hill or ridge) of sand accumulated and sorted by the action of wind or water.
Sand dune obligate species Plant or animal species found only in sand dune habitats.
Sandstone Sedimentary rock composed of sand-sized grains (usually quartz) cemented together.
Sandstorm Particles of sand carried aloft by strong wind. The sand particles are mostly confined to the lowest ten feet, and rarely rise more than fifty feet above…
Sanger sequencing A widely used method of determining the order of bases in DNA. See also: sequencing, shotgun sequencing
Sanitary waste Nonhazardous, nonradioactive liquid and solid waste generated by normal housekeeping activities.
Sanitary wastewater Wastewater (includes toilet, sink, shower, and kitchen flows) generated by normal housekeeping activities.
Santa Ana Wind In southern California, a weather condition in which strong, hot, dust-bearing winds descend to the Pacific Coast around Los Angeles from inland desert…
SAP Fluid content of the xylem and phloem cells of plants. Fluid content of the vacuole generally referred to as cell sap.
saprophyte An organism (generally a fungus) that depends on dead plant or animal tissue for its source of nutrition and metabolic energy.
SARA Title III Superfund Amendments and Reauthorization Act of 1986 known as the Emergency Planning and Community Right-to-Know Act of 1986.
Sastrugi Ridges of snow formed on a snow field by the action of the wind.
SAT 1. Satellite (imagery) 2. Saturday
satellite A chromosomal segment that branches off from the rest of the chromosome but is still connected by a thin filament or stalk.
satellite DNA Highly repetitive DNA in plant and animal genomes, consisting of millions of copies of sequences typically in the range 5-500 bp long.
Satellite Hydrology Program A NOHRSC program that uses satellite data to generate areal extent of snow cover data over large areas of the western United States.
satellite RNA A small, self-splicing RNA molecule that accompanies several plant viruses, including tobacco ringspot virus. Synonym: viroid.
Satellite RNA (viroids) A small, self-splicing RNA molecule that accompanies several plant viruses, including tobacco ringspot virus.
SATL Satellite
Saturated steam Steam at the temperature that corresponds to its boiling temperature at the same pressure.
Saturated unit weight The wet unit weight of soil when saturated. See unit weight.
Saturated zone A zone in which all voids are filled with water. The area below the water table where all open spaces are filled with water. See ground water.
Saturation Saturation The condition in which the partial pressure of any fluid constituent (water in the atmospheric air) is equal to its maximum possible partial…
Saturation (and internal vibration) A method of compacting soil using water added to soil and internal vibrators (such as a concrete vibrator) are worked down through the depth of soil…
Saturation Vapor Pressure The vapor pressure of a system, at a given temperature, wherein the vapor of a substance is in equilibrium with a plane surface of that substance's pure…
Savanna A flat grassland of tropical and subtropical regions usually having distinct periods of dry and wet weather.
Sawlog A log meeting minimum commercial requirements of diameter, length, and defect. The usual commercial requirements are a minimum of 8´ long with an inside…
SAWRS Supplementary Aviation Reporting Station - the SAWRS program addresses the concerns of users who depend on weather observations for air operations.
Sawtimber Live trees of commercial species containing at least one 12´ sawlog or two noncontiguous 8´ logs.
SBCAPE Surface Based CAPE; CAPE calculated using a Surface based parcel.
SBND Southbound
SBSD Subside
SC Abbreviation for synaptonemal complex.
SCA Abbreviation for specific combining ability.
Scaffold The central protein aceous core structure of condensed eukaryotic chromosomes. The scaffold is composed of non-histone chromosomal protein s.
Scalar A constant number. 1, -16, .3534, 7346 are all scalars.
Scale Ratio of map distance to Earth distance. Thus, in a 1:24,000 scale map, one centimeter, inch, or foot equals 24,000 centimeters, inches, or feet on the…
Scale Up Conversion of a process, such as fermentation of a micro-organism, from a small laboratory scale to a larger industrial scale.
Scaled sale A type of timber sale contract that specifies measuring or scaling of the included timber after removal.
Scaler An electronic instrument for counting radiation induced pulses from radiation detectors such as a Geiger-Muller tube.
Scaling Prying loose pieces of rock off a face or roof to avoid danger of their falling unexpectedly.
scanning electron microscope (Abbreviation: SEM). An electron-beam-based microscope used to examine, in a three dimensional screen image, the surface structure of prepared specimens.
SCAR Abbreviation for sequence characterized amplified region.
scarification The chemical or physical treatment given to certain seed s having hard, impermeable seed coats in order to puncture or weaken the seed coat sufficiently…
Scarify Loosening topsoil or breaking up the forest floor to improve conditions for seed germination or tree planting.
Scarp See Escarpment
Scatter When refering to photons and light, scattering describes the phenomenon of a source absorbing, and then emanating light in all directions.
Scattered When used to describe precipitation (for example: "scattered showers") - Area coverage of convective weather affecting 30 percent to 50 percent of a…
Scattering The process in which a beam of light is diffused or deflected by collisions with particles suspended in the atmosphere.
SCE Abbreviation for sister chromatid exchange.
Scenic integrity The degree of "intactness" of a landscape, which is related to the existing amount of visual disturbance present.
Scenic quality A measure of the intrinsic beauty of landform, water form, or vegetation in the landscape, as well as any visible human additions or alterations to the…
Scenic resources The visible physical features on a landscape (e.g., land, water, vegetation, animals, structures, and other features).
Scenic value The importance of a landscape based on human perception of the intrinsic beauty of landform, water form, and vegetation in the landscape, as well as any…
Scheduled outage Shutdown of a generating unit, or other facility, for inspection or maintenance, in accordance with an advance schedule.
Schist A metamorphic rock formed from many types of rocks. Minerals in the rocks include micas, chlorite, talc, hornblende, and garnets.
Schwann cell A type of glial cell of the peripheral nervous system that helps separate and insulate nerve cells.
Science Board An ACRF group made up of the ARM Science Team Executive Committee working group science chairs and climate research community appointees, that ensures…
Science Team Executive Committee (STEC) (STEC) The committee that provides recommendations, prioritization, coordination of activities, and program vision to the U.S.
Scintillation counter An instrument that detects and measures gamma radiation by counting the light flashes (scintillations) induced by the radiation.
scion A twig or bud used for grafting onto another plant or rootstock.
scion-stock interaction The effect of a rootstock on a scion (and vice versa) in which a particular scion grafted onto a specific s performs differently than it would either on…
sclerenchyma A strengthening tissue in plants, composed of cells with heavily lignified cell walls.
Scoping A first step in the NEPA process and in the river planning process. Scoping is a means of identifying issues and concerns, their significance, and the…
Scoria Congealed lava, usually of mafic composition and red or black in color, with a large number of vesicles formed by gases coming out of solution.
Scour Erosion in a stream bed, particularly if caused or increased by channel changes.
SCP Standing Committee on the Law of Patents
Scrape A nest made from scratching in the ground.
Scraper A stone tool that is modified for the specific task of scraping; for example, to scrape the meat from hides, to remove fat from the underside of a skin…
Scrapie A spongiform encephalopathy disease of sheep. See: proteinaceous infectious particle.
Scree Small, loose, rock debris covering a slope; a slope of loose rock debris at the base of a steep incline or cliff.
screen A screen is a set of criteria against which you measure stocks or other investments to find those that meet your criteria.
screen analysis Method for measuring a proportion of variously sized particles in solid fuels. The sample is passed through a series of screens of known size openings.
Scribing The cutting of a grid pattern of grooves in a semiconductor material, generally for the purpose of making interconnections.
Scrubber A device to clean combustible gas or stack gas by the spraying of water.
Scrubland An area of land that is uncultivated and covered with sparse stunted vegetation.
SCT Scattered
SCUD Small, ragged, low cloud fragments that are unattached to a larger cloud base and often seen with and behind cold fronts and thunderstorm gust fronts.
SDS Abbreviation for sodium dodecyl sulphate.
SDS-PAGE Abbreviation for sodium dodecyl sulphate polyacrylamide gel electrophoresis.
SE Southeast
Sea Breeze A thermally produced wind blowing during the day from a cool ocean surface onto the adjoining warm land, caused by the difference in the rates of heating…
Sea Breeze Convergence Zone The zone at the leading edge of a sea breeze where winds converge. The incoming air rises in this zone, often producing convective clouds.
Sea Breeze Front The leading edge of a sea breeze, whose passage is often accompanied by showers, a wind shift, or a sudden drop in temperature.
Sea Fog Common advection fog caused by transport of moist air over a cold body of water.
Sea Ice Any form of ice found at sea which has originated from the freezing of sea water (sea ice does NOT include superstructure icing).
Sea Level Pressure The sea level pressure is the atmospheric pressure at sea level at a given location.
Sea smoke Sea smoke (arctic sea smoke) Evaporation fog or steam fog which is formed when water vapor is added to air which is much colder than the vapor's source…
Sea surface temperature Sea surface temperature Temperature of the water film at the sea surface.
Sea Surface Temperatures The term refers to the mean temperature of the ocean in the upper few meters.