Science — page 104 of 132

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

Science terms

root cutting Cutting made from sections of roots alone.
root hairs Outgrowths from epidermal cell walls of the root, specialized for water and nutrient absorption.
root nodule A small round mass of cells attached to the roots of leguminous plants, containing symbiotic nitrogen-fixing bacteroids, particularly Rhizobium spp.
root tuber Thickened root that stores carbohydrates.
Root zone The volume of soil or growing medium containing the roots of a plant. In soil science, the depth of the soil profile in which roots are normally found.
rootstock The trunk or root material to which buds or scions are inserted in grafting. See: stock.
Rope (Also "Rope Funnel") - a narrow, often contorted condensation funnel usually associated with the decaying stage of a tornado. See rope stage.
Rope Cloud In satellite meteorology, a narrow, rope-like band of clouds sometimes seen on satellite images along a front or other boundary.
Rope Stage The dissipating stage of a tornado, characterized by thinning and shrinking of the condensation funnel into a rope (or rope funnel).
ROSA Remote Observing System Automation. A type of automated data transmitter used by NWS Cooperative Program observers.
Rossby Waves A series of troughs and ridges on quasi-horizontal surfaces in the major belt of upper tropospheric westerlies.
rotary shaker Rotating apparatus with a platform on which liquid media or cultures can be continuously shaken.
Rotation The number of years allotted to establish and grow a forest stand to maturity.
ROTG Rotating
Rotor An electric generator consists of an armature and a field structure. The armature carries the wire loop, coil, or other windings in which the voltage is…
Rotor Cloud A turbulent altocumulus cloud formation found in the lee of some mountain barriers when winds cross the barrier at high speed.
Rotten Ice Ice in an advanced stage of disintegration.
Rough fish A nonsport fish.
Rough Seas Sea conditions associated with regionally defined wind thresholds over bays, inlets, harbors, inland waters, and estuaries where larger waves are forming…
Rough trees Live trees of commercial species which do not contain a sawlog because of roughness, poor form, splits, or cracks.
Roundup-readyä Describing transgenic crop varieties that carry the bacterial gene which detoxifies the herbicide glyphosate, thereby making them resistant to its…
Roundwood Logs, bolts, or other round sections cut from trees.
Route alerting A supplement to the public alert system; a method for alerting people in areas not covered by the primary system or if the primary system fails.
Routing The methods of predicting the attenuation of a flood wave as it moves down the course of a river.
RPD Rapid
RPLC Replace
RPRT Report
RQR Require
rRNA See Ribosomal RNA.
RRQ Right Rear Quadrant - the area upstream from and to the right of an upper-level jet max (as would be viewed looking along the direction of flow).
RSG Rising
RSN Reason
RTE Route
RTRD Retard
RTRN Return
RTVS Real Time Verification System
Rubble dam A stone masonry dam in which the stones are unshaped or uncoursed. See dam.
RuBP Abbreviation for ribulose biphosphate.
RUC Rapid Update Cycle model, a numerical model run by NCEP that focuses on short-term forecasts out to 12 hours.
ruminant Animal having a rumen - a large digestive sac in which fibrous plant material is fermented by commensal microbes, prior to its digestion in a "true"…
Run Seasonal upstream migration of anadromous fish. One or more lengths of pipe that continue in a straight line.
Run-of-River Hydropower A type of hydroelectric facility that uses the river flow with very little alteration and little or no impoundment of the water.
Run-of-river plants The regulated inflow of one powerplant is equal to the outflow from a powerplant upstream.
Runner Typically said "runner-runner" to describe a hand that was made only by catching the correct cards on both the turn and the river.
Running and quick-start capability The net capability of generating units that carry load or have quick-start capability.
Runoff The water that flows off the surface of the land, ultimately into our streams and water bodies, without being absorbed into the soil.
Runup The vertical distance above the setup that the rush of water reaches when a wave breaks on the dam embankment.
Runway Visual Range The maximum distance at which the runway, or the specified lights or markers delineating it, can be seen from a position above a specified point on its…
Rural area Predominantly agricultural, prairie, forest, range, or undeveloped land where the population is small.
Rural electric cooperative (cooperatively-owned electric utility) A customer-owned electric utility that was created to transmit and distribute power in rural areas.
Rural Electrification Administration (REA) (REA) An agency of the U.S. Dept. of Agriculture that makes loans to states and territories in the U.S.
rust A generic descriptor for various serious fungal plant pathogens, which infect the leaves and stems of crops.
RVA River Summary, a NWS summary of river and/or crest stages for selected forecast points along the river.
RVF River Forecast. An internal product issued by RFCs to other NWS offices. An RVF contains stage and/ or flow forecasts for specific locations based on…
RVI River Ice Statement
RVR 1. Runway Visual Range - the maximum distance at which the runway, or the specified lights or markers delineating it, can be seen from a position above a…
RVS 1. Abbreviation for "revise" 2. River Statement, a product issued to communicate notable hydrologic conditions which do not involve flooding, i.e.
RW Rainshower
S 1) South or 2) Snow
S phase The phase in the cell cycle during which DNA synthesis occurs.
S&E See U.S. Department of Agriculture.
S-Band Radar These were in use as network radars in the National Weather Service prior to the installation of the WSR 88-D radars.
S/W Shortwave - a disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it.
S/WV Shortwave - a disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it.
S1 mapping A method to characterise post-transcriptional modifications in RNA (removal of introns etc.
S1 nuclease An enzyme obtained from the filamentous fungus Aspergillus oryzae which specifically degrades RNA or single-stranded DNA into its constituent…
saccharide A simple sugar or a more complex compound that can be hydrolyzed to simple sugar units.
saccharifaction Following liquefaction, the hydrolysis of polysaccharides by glucoamylase to maltose and glucose.
saccharification A conversion process using acids, bases, or enzymes in which long-chain carbohydrates are broken down into their component fermentable sugars.
Sacramento Soil Moisture Accounting Model (SACSMA) (SACSMA) A hydrologic model which simulates the movement and occurrence of water in and on top of the ground.
Sacred landscapes Natural places recognized by a cultural group as having spiritual or religious significance.
Sacred site Any specific, discrete, narrowly delineated location on federal land that is identified by an Indian tribe, or Indian individual determined to be an…
Sacrificial Anode A metal rod placed in a water heater tank to protect the tank from corrosion. Anodes of aluminum, magnesium, or zinc are the more frequently metals.
Saddle dam A subsidiary dam of any type constructed across a saddle or low point on the perimeter of a reservoir. See dike.
Safe Drinking Water Act (SDWA) (SDWA) The Safe Drinking Water Act (SDWA) ensures that our tap water is fit to drink. Passed in 1974, SDWA sets national drinking water standards for public…
Safe Drinking Water Act (SWDA) (SWDA) Act authorizing development of maximum contaminant levels for drinking water applicable to public water systems (i.e.
Safe harbor The ability of management to discuss in good faith a company's prospects and financial projections with analysts and investors without fearing litigation.
Safe yield The amount of groundwater that can be withdrawn from a groundwater basin over a period of time without exceeding the long-term recharge of the basin or…
Safety Disconnect An electronic (automatic or manual) switch that disconnects one circuit from another circuit.
Safety Evaluation Earthquake (SEE) The earthquake expressed in terms of magnitude and closest distance from the damsite or in terms of the characteristics of the time history of free-field…
Safety evaluation flood (SEF) The largest flood for which the safety of a dam and appurtenant structure(s) are to be evaluated.
Safety Evaluation of Existing Dams (SEED) examination The onsite examination performed initially and at predetermined intervals (approximately every 6 years).
Safety Evaluation of Existing Dams (SEED) report A compilation of independent technical reports that evaluate the design, construction, and performance of a dam for its structural and hydraulic integrity…
SafetyNET Inmarsat-C SafetyNET is an internationally adopted, automated satellite system for promulgating weather forecasts and warnings, marine navigational…
Saffir-Simpson Hurricane Wind Scale The Saffir-Simpson Hurricane Wind Scale is a 1 to 5 categorization based on the hurricane's intensity at the indicated time.
Saffir-Simpson Scale This scale was developed in an effort to estimate the possible damage a hurricane's sustained winds and storm surge could do to a coastal area.
Sahara a large desert in northern Africa.
Sahel a large savanna in northern Africa.
Saline A solution of salt and water.
saline resistance Synonym for salt tolerance.
Saline sodic land Soil that contains soluble salts in amounts that impair plant growth but not an excess of exchangeable sodium.
Saline water Water that contains more than 1,000 milligrams per liter of dissolved solids.
Salinity A measure of the amount of salt and other mineral substances dissolved in water.
Salinity (SAL) In oceanography, conductivity is measured and converted to salinity by a known functional relationship between the measured electrical conductivity of…
Salivary gland (SA-lih-VAYR-ee gland) A gland in the mouth that produces saliva.
Salmonella A genus of rod-shaped, gram-negative bacteria that are a common cause of food poisoning.
Salmonids Family of fish that includes salmon and steelhead.
Salt flat Low-lying ground where salts collect in the soil because of the evaporation of standing water.
Salt Gradient Solar Ponds Consist of three main layers. The top layer is near ambient and has low salt content.
salt tolerance The ability of a plant in soil or in culture to withstand a concentration of common salt (sodium chloride) which is damaging or lethal to most other…