"Not In My Backyard" (NIMBY)NIMBY is an acronym for the "Not in my backyard" sentiment that exists among some people who do not want any type of change in their neighborhood.
NAMThe operational North American Meso (NAM, formerly Eta) is run four times per day (00,06,12,18Z), all cycles run to 84-h.
Name PlateA metal tag attached to a machine or appliance that contains information such as brand name, serial number, voltage, power ratings under specified…
Nanotesla (nT)A unit of magnetism equal to 10-9 tesla, equivalent to a gamma (10-5 gauss).
NAONorth Atlantic Oscillation - the NAO is a large-scale fluctuation in atmospheric pressure between the subtropical high pressure system located near the…
NAO IndexThis index measures the anomalies in sea level pressure between the Icelandic low pressure system and the Azores high pressure system in the North…
NaphthaA generic term applied to a petroleum fraction with an approximate boiling range between 122 and 400 degrees Fahrenheit.
narrow-host-range plasmidA plasmid that can replicate in one, or at most a few, different bacterial species.
narrow-sense heritabilityThe proportion of the phenotypic variance that is due to variation in breeding values; the proportion of the phenotypic variance that is due to additive…
National Ambient Air Quality StandardsIn the United States, national standards for the ambient concentrations in air of different air pollutants designed to protect human health and welfare.
National balancing point (NBP)Location of wholesale natural gas trading in the United Kingdom; a key reference point for spot and forward market natural gas transactions in Europe.
National Climatic Data CenterThe agency that archives climatic data from the National Oceanic and Atmospheric Administration, as well as other climatological organizations.
National Digital Forecast Database(NDFD)- The National Weather Service's NDFD provides access to gridded forecasts of sensible weather elements (e.g.
National disaster medical systemA system designed to deal with extensive medical care needs in very large disasters or emergencies.
National Electrical Code (NEC)The NEC is a set of regulations that have contributed to making the electrical systems in the United States one of the safest in the world.
National Environmental Policy Act (NEPA)A comprehensive federal law requiring analysis of the environmental impacts of federal actions such as the approval of grants; also requiring preparation…
National Environmental Policy Act of 1969 (NEPA)Requires federal agencies to prepare a detailed statement on the environmental impacts of their proposed major actions that are significantly affecting…
National Fire Danger Rating SystemA uniform fire danger rating system used in the United States that focuses on the environmental factors that impact the moisture content of fuels.
National Flood SummaryThis NWS daily product (abbreviated FLN) contains nationwide information on current flood conditions.
National Forest Management Act (NFMA)A federal law passed in 1976 as an amendment to the Forest and Rangeland Renewable Resources Planning Act requiring the preparation of Regional Guides and…
National Historic Preservation Act (NHPA)A federal law providing that property resources with significant national historic value be placed on the National Register of Historic Places.
National Historic TrailsThese trails are designated by Congress under the National Trails System Act of 1968 and follow, as closely as possible, on federal land, the original…
National Hurricane CenterOne of three branches of the Tropical Prediction Center (TPC). This center maintains a continuous watch on tropical cyclones over the Atlantic, Caribbean…
National Hurricane Operations Plan(NHOP) - The NHOP is issued annually by the Federal Coordinator for Meteorological Services and Supporting Research.
National Landscape Conservation System (NLCS)Created by the BLM in June 2000 to increase public awareness of BLM lands with scientific, cultural, educational, ecological, and other values.
National MonumentAn area designated by the President of the United States, under the authority of the Antiquities Act of 1906, to protect objects of scientific and…
National Park Service (NPS)The National Park Service preserves unimpaired the natural and cultural resources and values of the national park system for the enjoyment, education, and…
National Parks(U.S.) A large area of land preserved in its natural state as public property.
National Recreation AreaAn area designated by Congress to assure the conservation and protection of natural, scenic, historic, pastoral, fish, and wildlife values, and to provide…
National Register of Historic PlacesA federally maintained register of districts, sites, buildings, structures, architecture, archeology, and culture.
National Register of Historic Places (NRHP)A comprehensive list of districts, sites, buildings, structures, and objects that are significant in American history, architecture, archaeology…
National Response Center (NRC)Located at the U.S. Coast Guard Headquarters in Washington, D.C., the NRC is a 24-hour national communications center and the single point of contact for…
National Response Team (NRT)NRT consists of representatives from several Federal agencies including the Department of the Interior (DOI) and the Bureau of Reclamation.
National Science Foundation (NSF)A nonregulatory agency which has oversight of biotechnology research activities that the agency funds.
National Severe Storms LaboratoryThis is one of NOAA's internationally known Environmental Research Laboratories, leading the way in investigations of all aspects of severe weather.
National System of MPAsThe group of MPA sites, networks, and systems established and managed by federal, state, territorial, tribal, and/or local governments that collectively…
National Warning System (NAWAS)A dedicated, commercially leased, nationwide voice telephone warning system operated on a 24-hour basis, with a National Warning Center and an Alternate…
National Weather and Crop SummaryA product of the National Agricultural Statistics Service, Agricultural Statistics Board, and U.S. Department of Agriculture.
National Weather Service (NWS)The National Weather Service provides weather, hydrologic, and climate forecasts and warnings for the United States, its territories, adjacent waters and…
Nationwide Rivers Inventory (NRI)The Nationwide Rivers Inventory is a listing of more than 3,400 free-flowing river segments in the United States that are believed to possess one or more…
Native AmericanOf, or relating to, a tribe, people, or culture that is indigenous to the United States. (See Native American Graves Protection and Repatriation Act)
native ligninThe lignin as it exists in the lignocellulosic complex before separation.
Native loadWholesale and retail customers that the electric transmission provider is obligated to serve.
native proteinThe naturally occurring form of a protein.
Natural ControlA stream gaging control which is natural to the stream channel, in contrast to an artificial control structure by man.
Natural CoolingSpace cooling achieved by shading, natural (unassisted, as opposed to forced) ventilation, conduction control, radiation, and evaporation; also called…
Natural DraftDraft that is caused by temperature differences in the air.
Natural drainagesNatural systems that convey water (such as a stream channel) that may be perennial, intermittent, or ephemeral.
Natural floodwayThe channel of a water course and those portions of the adjoining flood plain which are reasonably required to carry a selected probability flood.
Natural frequency (f)The natural frequencies of a structure are the frequencies of free vibration. Free vibration is vibration that occurs in the absence of forced vibration.
Natural gasA hydrocarbon gas obtained from underground sources, often in association with petroleum and coal deposits.
Natural gas liquids (NGLs)Those hydrocarbons in natural gas that are separated as liquids from the gas. Includes natural gas plant liquids and lease condensate.
Natural Gas Steam Reforming ProductionA two step process where in the first step natural gas is exposed to a high-temperature steam to produce hydrogen, carbon monoxide, and carbon dioxide.
Natural killer cellA type of white blood cell that contains granules with enzymes that can kill tumor cells or microbial cells.
Natural period of vibration (T)The period of vibration of a a structure is the time required for one cycle of the simple harmonic motion in one of these characteristic patterns (shapes).
Natural ScienceThe sciences involved in the study of the physical world and its phenomena.
Natural selectionThe differential survival and reproduc- tion of organisms with genetic characteristics that enable them to better utilize environmental resources.
Natural VentilationVentilation that is created by the differences in the distribution of air pressures around a building.
NaturalnessArea which generally appears to have been affected primarily by the forces of nature, with the imprint of man's work substantially unnoticeable.
NatureServeA nonprofit organization that provides the scientific information and tools needed to guide effective conservation action.
NatureServe ExplorerA Web site from NatureServe that provides authoritative conservation information in a searchable database for more than 70,000 plants, animals, and…
Nautical DawnThe time at which the sun is 12 degrees below the horizon in the morning. Nautical dawn is defined as that time at which there is just enough sunlight for…
Nautical DuskThe time at which the sun is 12 degrees below the horizon in the evening. At this time, objects are no longer distinguishable.
Nautical MileA unit of distance used in marine navigation and marine forecasts. It is equal to 1.15 statue miles or 1852 meters.
Nautical TwilightThe time after civil twilight, when the brighter stars used for celestial navigation have appeared and the horizon may still be seen.
Navigable watersWaters of the United States including: (a) All waters that are currently used, were used in the past, or may be susceptible to use in interstate or…
Navigation MethodsThree basic methods of providing and managing inland waterways - 1) Run-of-the-River: no provision of upstream storage; 2) Slack-Water: locks and dams…
NAVTEXAn international automated medium frequency (518 kHz) direct-printing service for delivery of navigational and meteorological warnings and forecasts, as…
NAVTEX Forecast(NAV) - A National Weather Service marine forecast combining various Coastal Waters and Offshore forecasts, optimized to accommodate transmission via…