Science terms starting with E

619 terms

E East
E REGION In solar-terrestrial terms, a daytime layer of the earth's ionosphere roughly between the altitudes of 85 and 140 km.
E site See: exit site.
E-10 A mixture of 10% ethanol and 90% gasoline based on volume.
E-19, Report on River Gage Station A report to be completed every 5 - 10 years providing a complete history of a river station and all gages that have been used for public forecasts since…
E-19a, Abridged Report on River Gage Sta In hydrologic terms, an abridged version of an E-19, an E-19a updates the E-19 as additional information, or changes occur at the station during the…
E-19a, Abridged Report on River Gage Station An abridged version of an E-19, an E-19a used to be used to update the E-19 as additional information, or changes occur at the station during the…
E-3, Flood Stage Report A form that a Service Hydrologist/ Hydrology Focal Point completes to document the dates in which forecast points are above flood stage, as well as the…
E-5, Monthly Report of River and Flood c In hydrologic terms, a monthly narrative report covering flooding which occurred over the past month.
E-5, Monthly Report of River and Flood conditions A monthly narrative report covering flooding which occurred over the past month.
E-7, Flood Damage Report A report to be completed anytime there is reported flood damage or loss of life as a direct result of flooding.
E-85 A mixture of 85% ethanol and 15% gasoline based on volume.
E. coli See: Escherichia coli.
E85 A high-level gasoline-ethanol blend containing 51% to 83% ethanol, depending on geography and season.
EA enterprise architecture
Early Archaic The period 7,500 to 5,000 years B.P.
Early seral species Shrubs (such as ceanothus) and hardwoods (usually in tree form, such as red alder, bitter cherry and big leaf maple) that start growing in natural…
Early warning system (EWS) A designed system that will ensure timely recognition of a threatening event and provide a reliable and timely warning and evacuation of the population at…
Early warning system feasibility Study of the feasibility of installing some level of Early Warning System to meet the target times for alerts and warnings.
Earth Berm A mound of dirt next to exterior walls to provide wind protection and insulation.
Earth Cooling Tube A long, underground metal or plastic pipe through which air is drawn. As air travels through the pipe it gives up some of its heat to the soil, and enters…
Earth dam (earthfill dam) An embankment dam in which more than 50 percent of the total volume is formed of compacted earth material generally smaller than 3-inch size.
Earth Dam or Earthfill Dam See "Dam".
Earth lining Compacted layer of earth on surface of canal or other excavation.
Earth pressure The pressure or force exerted by soil on any boundary. See active earth pressure, at-rest earth pressure, and passive earth pressure.
Earth radiation Earth radiation (terrestrial radiation) The total infrared radiation emitted from the Earth's surface; to be carefully distinguished from effective…
Earth Sheltered Houses Houses that have earth berms around exterior walls.
Earth-Coupled Ground Source (Geothermal) Heat Pump A type of heat pump that uses sealed horizontal or vertical pipes, buried in the ground, as heat exchangers through which a fluid is circulated to…
Earth-Ship A registered trademark name for houses built with tires, aluminum cans, and earth.
Earthen (or Earthfill) Dam An embankment dam in which more than 50% of the total volume is formed of compacted fine-grained material.
Earthern cattle tank A watering area or basin for cattle that is usually created in a natural drainage area by obstructing natural water flows with berms of soil.
Earthquake Ground shaking caused by the sudden release of energy stored in rock beneath the Earth's surface.
Earthwork Any one or combination of the operations involved in altering or movement of earth.
Easement A right to the use of, or access to, land owned by another.
Easterlies Any winds with components from the east.
Eastern North Pacific Basin The portion of the North Pacific Ocean east of 140W. The National Hurricane Center in Miami, Florida is responsible for tracking tropical cyclones in this…
Ebb Current The movement of a tidal current away form the coast or down an estuary.
EBND Eastbound
EBS Emergency Broadcast System
EBV A common virus that remains dormant in most people. It causes infectious mononucleosis and has been associated with certain cancers, including Burkitt…
EC See: Enzyme Commission number.
ECC Eastern Colorado Area Office (Loveland, CO).
Eccentric A device for converting continuous circular motion into reciprocating rectilinear motion.
Eccentricity A dimensionless quantity describing the elliptical shape of a planet's orbit.
ecdysone A steroid hormone in insects stimulating the synthesis of proteins involved in moulting and metamorphosis.
Echo Energy back scattered from a target (precipitation, clouds, etc.) and received by and displayed on a radar screen.
Echo Tops The height above ground of the center of the radar beam using the tilt, or scan, that contains the highest elevation where reflectivities greater than 18…
eclosion 1. Emergence of an adult insect from the pupal stage. 2. Initial phase of germination of fungal spores.
ECMF European Center for Meteorology Forecast model.
ECMWF European Center for Medium-Range Weather Forecasts. Operational references in forecast discussions typically refer to the ECMWF's medium-range numerical…
ecological diversity See: biodiversity.
Ecological Footprint The impact of humans on ecosystems created by their use of land, water, and other natural resources.
Ecological Network A set of discrete MPAs within a region that are connected through dispersal of reproductive stages (eggs, larvae, spores, etc.
Ecological Resilience The capacity of an ecosystem or natural population to resist or recover from major changes in structure and function following natural and human-caused…
Ecological resources Biota (fish, wildlife, and plants) and their habitats, which may be land, air, or water.
Ecological segmentation Development that fragments animal habitat and does not provide corridors for movement.
Ecology The study of the interactions of organisms with their environment and with each other.
Economic analysis A procedure that includes both tangible and intangible factors to evaluate various alternatives.
Economic Opportunity Area (EOA) An area or several areas within a designated Massachusetts Environmental Target Area of particular need and priority for economic development.
Economic sector A subdivision of economic activities based on major purpose (for example, "commercial sector" or "private sector").
economic trait locus (Abbreviation: ETL). A locus influencing a trait that contributes to producer's income.
Economizer A heat exchanger for recovering heat from flue gases for heating water or air.
Economy The way a country manages its money and resources (such as workers and land) to produce, buy, and sell goods and services.
Ecoregion A geographically distinct area of land that is characterized by a distinctive climate, ecological features, and plant and animal communities.
Ecosystem A complex ecological community or environment forming a functioning whole.
Ecotones The borders between two different types of ecosystems or communities (e.g., a forest and a grassland) containing characteristic species of each.
ecotype A population or a strain of an organism that is adapted to a particular habitat.
Ectoderm The outer of three germ layers of the early embryo that gives rise in later development to the skin, cells of the amnion and chorion, nervous system…
ectopic Anomalous situation or relation, particularly with respect to pregnancy, where the foetus is implanted outside the uterus.
Eddy Circular current of water moving against the main current. See recirculation zone.
Edge habitat The transitional zone where one cover type ends and another begins.
Edge-Defined Film-Fed Growth (EFG) A method for making sheets of polycrystalline silicon (for solar photovoltaic devices) in which molten silicon is drawn upward by capillary action through…
Edge-on A descriptor for the appearance of solar facility collector/reflector arrays when viewed at very low vertical angles, such that the viewing angle is at or…
edible vaccine Edible antigen-containing material, that activates the immune system via gut-associated lymphoid tissues.
Edison Electric Institute (EEI) The Edison Electric Institute is an association of electric companies formed in 1933 "to exchange information on industry developments and to act as an…
editing See: splicing (1).
Edmonton protocol A procedure (developed in Canada) for transplanting pancreatic islet cells to the liver of a patient with Type I diabetes.
EDT Eastern Daylight Time
EDTA See: ethylenediamine tetraacetic acid.
EDV Abbreviation for essential derivation of varieties.
EEO equal employment opportunity.
EFCT Effect
Effective Capacity The maximum load that a device is capable of carrying.
Effective diameter Particle diameter corresponding to 10 percent finer on the accumulative gradation curve.
effective emissivity A correction factor, dependent on the radiational characteristics of the earth-atmosphere system, that permits application of black body radiation laws to…
Effective force The force transmitted through a soil or rock mass by intergranular pressures.
Effective peak ground acceleration That acceleration which is most closely related to structural response and to damage potential of an earthquake.
Effective Porosity The ratio of the volume of a soil or rock mass that can be drained by gravity to the total volume of the mass.
Effective Precipitation 1) That part of the precipitation that produces runoff. 2) A weighted average of current and antecedent precipitation that is "effective" in correlating…
Effective Precipitation (Rainfall) (1) That part of the precipitation that produces runoff. (2) A weighted average of current and antecedent precipitation that is "effective" in correlating…
Effective Terrestrial Radiation The difference between upwelling infrared or terrestrial radiation emitted from the earth and the downwelling infrared radiation from the atmosphere
Effective Topography The topography as seen by an approaching flow, which may include not only the actual terrain but also cold air masses trapped within or adjacent to the…
effector cells Cells of the immune system that are responsible for the production of cell-mediated cytotoxicity.
effector molecule A molecule that influences the behaviour of a regulatory molecule, such as a repressor protein, thereby influencing gene expression.
Effects Environmental consequences (the scientific and analytical basis for comparison of alternatives) as a result of a proposed action.
Efficacy Effectiveness. In medicine, the ability of an intervention (for example, a drug or surgery) to produce the desired beneficial effect.
Efficiency Under the First Law of Thermodynamics, efficiency is the ratio of work or energy output to work or energy input, and cannot exceed 100 percent.
Efficiency (Appliance) Ratings A measure of the efficiency of an appliance's energy efficiency.
Effigy An object bearing the likeness of an animal or human.
Effluent The treated waste water discharged by sewage treatment plants.