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absorptionMeasure of a surface's capacity to absorb incident energy, often at well-defined wavelengths.absorptionabsorptie
active sedimentary basinsBasin where the processes of sedimentation and tectonic deformations are presently active. It is characterised by the presence of active faults and earthquakes.bassin de sédimentation activeactief sedimentair bekken
additive synthesisMethod of producing full-color images by mixing light of the three primary color wavelengths, blue, green and red.synthèse additiveadditieve synthese
aeolianCaused by wind; refers to the erosion, transportation, and deposition of materials. Such processes tend to operate more efficiently in arid and semi-arid climateséolieneolisch
aerial photographyPhotography from airborne platforms.photographies aériennesluchtfotografie
aerodynamic diametersAs particles are often non-spherical (for example, asbestos fibers), there are many definitions of particle size. The most widely used definition is the aerodynamic diameter. A particle with an aerodynamic diameter of 10 µm moves in a gas like a sphere of unit density (1 g/cm³) with a diameter of 10 µm.diamètre aérodynamiqueaerodynamische diameters

Colloidal system, such as a mist in which the dispersion medium is a gas.

Agenda21A dynamic UN programme of specific objectives and actions for a "new global partnership for sustainable development".Agenda21Agenda21
algorithmChronologic series of different formulas and/or simple calculation procedures in order to obtain results from data.algorithmealgoritme
alluviumUnconsolidated material transported and then deposited by flowing streams or river water in a riverbed, a flood plain, or a delta.alluvionalluvium
andesiteA fine-grained, frequently porphyritic, igneous rock. Phenocrysts are plagioclase feldspars with biotite, pyroxene and/or hornblende. The groundmass has essentially the same mineralogy as the phenocrysts.andésiteandesiet
anomalyIrregularity, deviation from a standard situation.anomalieanomalie
anthropogenicOriginating from the activity of humans.anthropiqueantropogeen
arcticExtended area near the North Pole delimited by the arctic polar circle.arctiquearctisch
aridClimate or habitat with less than 250 mm annual rainfall, very high evaporation and sparse vegetationaridearied
artefactArtificial phenomenon found during an observation or an experiment.artefactartefact
attributeIn GIS geomatric attributes define the three-dimensional localisation of a phenomenon while thematic attributes define the thematic characteristics of the localised phenomena.attributattribuut
autotrophic respirationThe process by which an organism utilizes carbon dioxide as a source of carbon and obtain their energy from the sun or by oxidizing inorganic substances such as sulphur, hydrogen, ammonium, and nitrate salts.respiration autotropheautotrofe ademhaling
backscatterThe portion of the out-going radar signal that the target redirects directly back towards the radar antenna. If the signal formed by backscatter is undesired, it is called "clutter". Other portions of the incident radar energy may be reflected or absorbed or scattered away from the radar.rétrodiffusionterugverstrooiing / backscatter
basaltA fine-grained basic igneous rock. The essential minerals of basalt are anorthite-rich plagioclase, feldspar and augite. It is typically found as a lava flow.basaltebasalt
bathymetryMeasurement of the depth of large bodies of water using different techniques.bathymétriebathymetrie
biodiversityThe biological diversity of an area as a function of the amounts of animal or plant species present, their uniqueness and specifivity, and the number of individuals of each species.biodiversitébiodiversiteit (biologische verscheidenheid)
biomassTotal mass of living organic matter (plants, animals, micro-organisms) present in a habitat.biomassebiomassa
black bodyIn physics, a surface that absorbs all radiant energy falling on it. The term arises because incident visible light will be absorbed rather than reflected, and therefore the surface will appear black. The concept of such a perfect absorber of energy is extremely useful in the study of radiation phenomena.corps noirzwart lichaam
block diagramThree-dimensional model of a part of the terrestrial surface representing its topographic surface. The model allows to reproduce phenomena on the surface (e.g. land use) or under the surface (e.g. geological structure). Block diagrams are also used to visualise socio-economic or physical phenomena in the z-dimension (height) of the diagram.bloc-diagrammeblokdiagram
bufferingA spatial analysis or map algebra function that creates an extension zone around a point, line or polygon by locating its boundaries at a user-defined distance from tampon / région tamponbuffergebied
ByteSeveral (usually eight) binary bits of data grouped together to represent a character, digit, or other value.octetbyte
canyonA narrow chasm with steep cliff walls, cut into the earth by running water; a gorge.canyoncanyon
carbon balanceThe balance of the exchanges (incomes and losses) of carbon between the carbon reservoirs or between one specific loop (e.g. atmosphere/ biosphere) of the carbon cycle.bilan carbonekoolstofbalans
carrying capacityRepresents the maximal number of a species that a biotope can support without a risk for its survival.capacité d'accueildraagkracht
cartographyThe science of representing as accurately as possible the earth's surface of parts of it on a flat or spherical surface. Cartography also studies methods for the representation on a flat surface of the features of a curved surface.cartographiecartografie
catchment areaArea determined by topographic features within which falling rain will contribute to runoff to a particular point under consideration. The area tributary to a lake, stream, sewer or drain.bassin versantstroomgebied
centrifugal forceThe component of apparent force on a body in curvilinear motion, as observed from that body, that is directed away from the center of curvature or axis of rotation. The opposite is a centripetal force.force centrifugecentrifugale kracht
CFCChlorofluorocarbon. A family of compounds of chlorine, fluorine, and carbon, entirely of industrial origin. CFCs include refrigerants, propellants for spray cans and for blowing plastic-foam insulation, styrofoam packaging, and solvents for cleaning electronic circuit boards. The compounds' lifetimes vary over a wide range, exceeding 100 years in some cases. CFCs' ability to destroy stratospheric ozone through catalytic cycles is contributing to the depletion of ozone worldwide. Into the stratosphere, the molecules are bombarded by ultraviolet rays, causing the CFCs to break up and release their chlorine atoms, which participate in ozone destruction (a single atom of chlorine is able to destroy ozone molecules over and over again). Since 1989 the use of CFC's was limited.CFCCFK

SiO2, an opaque chalcedony that is bedded and massive, fractures in a conchoidal fashion and is generally dull grey-black in colour.

chlorophyllGreen plant pigment, synthetizised in the chloroplasts in the presence of light and playing a essential role in the photosynthesis.chlorophyllechlorofyl
classificationGrouping image pixels into categories or classes to produce a thematic representation.classificationclassificatie
climate changeA change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods. This term is commonly used interchangeably with "global warming" and the "greenhouse effect", but is a more descriptive term. Climate change refers to the buildup of man-made gases in the atmosphere that trap the suns heat, causing changes in weather patterns.changements climatiquesklimaatsveranderingen
Climatic efficiencyProportion of PAR (photosynthetically active radiation) over total radiation.efficacité climatologiqueklimatologische efficiëntie
coherenceProperty of a signal or data set in which the phases of the constituents are statistically correlated, or systematically related.cohérencecoherentie
colour compositeA colour image produced through optical combination of multiband images by assigning the three primary colours (blue, green and red) to three selected channels of an image.composition coloréekleurencomposiet
contrast enhancementA radiometric enhancement technique used to improve the visual contrast of an image. It matches the data's dynamic range to the dynamic range of the display medium (photographic or digital).rehaussement de contrastecontrastverbetering
coordinates systemSystem to localise each point at the Earth's surface using units of choice. The latitude, longitude en altitude correspond to a position on the Earth's surface, The system accounts for the dimensions and the shape of the Earth.système de coordonnéescoördinatenstelsel
CorineThe Corine programme of the EU had three objectives: - collecting information on the environment in priority domains, - coordonnate the efforts to gather and organise data on the level of the member states or on international level, - guarantee the coherence of the information and assure the recording of the data.Coordination des informations sur l'environnement (Corine)Corine
correlationA relation existing between phenomena or things or between mathematical or statistical variables which tend to vary, be associated, or occur together in a way not expected on the basis of chance alone.corrélationcorrelatie
crop growth modelModel based on data on crops, soils and management practices which can help farmer predict crop growth and yield.modèle de croissance des culturesgewasgroeimodel
cynegeticsRelative to hunting and game.cynégétiquecynegetica
databaseAny collection of information on a specific subject or area. Specifically, a computerized collection of such information.banque de donnéesgegevensbank
desertificationThe gradual enlargement and encroachment of deserts into formerly marginal arid lands, caused by climatic factors such as prolonged drought and by overgrazing and overcultivation.désertificationdesertificatie
diachronicPhenomenon whereby a layer with a constant facies [characterising appearance or composition of a rock or stratified body] varies in age from place to place.diachroniquediachroon
digital-format. Opposite of analog format. Used for data coded in a discrete, numerical format.digitaldigitaal
Digital Elevation Model(DEM). A geographic grid of an area where the contents of each grid cell represents the height of the terrain in that cell. Buildings, trees or other features on the ground are not included in the elevation values. In most cases used synonymously with DTM (Digital Terrain Model).Modèle Numérique d’ElévationDigitaal Hoogtemodel
Digital Surface Model

(DSM) A geographic grid of an area where the contents of each grid cell represents the height of the ground plus all features on it (trees, buildings, ...) in that cell.

Modèle numérique de surfaceDigital Oppervlaktemodel
Digital Terrain Model (DTM). A geographic grid of an area where the contents of each grid cell represents the height of the terrain in that cell. Buildings, trees or other features on the ground are not included in the elevation values. In most cases used synonymously with DEM (Digital Elevation Model).Modèle Numérique de TerrainDigitaal Terreinmodel
digitiseTransformation of analogue data into numeric data (using a digitizing table).digitalisationdigitaliseren
Dobson unit

The standard way to express ozone amounts in the atmosphere. One DU is 2,7 x 10-16 ozone molecules per square centimeter. One DU refers to a layer of ozone that would be 0.001 cm thick under conditions of standard temperature and pressure.

Unité DobsonDobson eenheid
EcologyScience dealing with the interrelationships between living organisms and their environments.écologieecologie
Economic Exclusion ZoneAll marine waters from the outer edge of the Territorial Sea (12 nautical miles) seaward for 188 nautical miles until the 200 nautical mile limit. The EEZ refers to the rights of coastal states to control the living and nonliving resources of the sea for 200 miles off their coasts while allowing freedom of navigation to other states beyond 12 miles, as agreed at the sixth session of the Third U.N. Conference on the Law of the Sea (UNCLOS). The EEZ also gives the coastal states the responsibility for managing the conservation of all natural resources within the 200-mile limit.Zone d'Exclusion EconomiqueEconomic Exclusion Zone
ecosystemThe interacting system of a biological community and its non-living environmental surroundings.écosystèmeecosysteem
erosionThe transportation of particles produced by weathering by a variety of agents including moving ice, flowing water, wind and mass movement.érosionerosie
escarpmentA steep slope created by erosion or faulting.escarpementsteilrand
estuaryThe point at which the mouth of a river enters the sea and freshwater and seawater are mixed; a place where tides ebb and flow.estuaireestuarium
eutrophicationExcessive enrichment of water with nutrients, momentarily or durably, notably linked to input of natural or synthetic fertilizers, which favours the growth of algues and other microscopic plants and results in a decrease of the water's oxygen content.eutrophisationeutrofiëring
extrapolationExtrapolate: to predict by projecting past experience or known data.extrapolationextrapolatie
false colour compositeAn image produced by displaying multiple spectral bands as colours different from the spectal range they were taken in.composition fausses couleursvalse kleuren composiet
fAPARRatio of incident PAR-radaiation (Photosynthetic Active Radaiation) absorbed by vegetation. fAPAR represents the fraction of efficiency of absorbed PAR-radiation.fAPARfAPAR
faultA fracture in the continuity of a rock formation caused by a shifting or dislodging of the earth's crust, in which adjacent surfaces are differentially displaced parallel to the plane of fracturefaillebreuk
feeding groundPlace where wild animals feed. The feeding ground may be artificial, i.e. created on purpose to feed the animals: food patches or improved meadows.gagnagevoederplaats
field of viewThe area or solid angle which can be viewed through an optical instrument.champ de viséegezichtsveld
filteringA mathematical procedure which selectively modifies the values of numerical data.filtragefilteren
forest not under state controlHere used for the Walloon region 'Forêt non soumise': The total of forests not managed by the forestry administration of the Walloon Region.forêt non soumiseBos niet onder staatscontrole
forest under state controlHere used for the Walloon region 'Forêt soumise': The total of forests managed by the forestry administration of the Walloon Region.forêt soumisebos onder staatscontrole
fossil fuelsThe ancient, altered remains of organisms that are extracted from the surface/near-surface parts of the Earth's crust and used as fuel; predominantly coal, natural gas and oil. They account for ca. 82% of the world's energy consumption.combustibles fossilesfossiele brandstoffen
fraction imageA fraction image is a map, resulting from a soft classification procedure, representing a single class (e.g. vegetation, water,..). Each pixel on this a map has been attributed a value ranging from 0 to 100 with 0 indicating that the class in question does not occur within the pixel, while a value of 100 means that no other class is present in the pixel. Mostly, the value is between those extremes.image fractionnéefractiebeeld
fuzzy logicIn mathematics, a form of logic based on the concept of the fuzzy set. Membership in fuzzy sets is expressed in probabilities or degrees of truth, i.e., as a continuum of values ranging from 0 to 1.logique flouevaagheidslogica
gallery forestA forest growing along a watercourse in a region otherwise devoid of trees.forêt galeriegalerijbos
geo-archaeologyGeo-archaeology is an area of specialization within archaeology. Geo-archaeologists focus on the interaction between artifacts, sites, and natural geological processes.géo-archéologiegeo-archeologie
geocentric coordinatesThe position of a locality relative to the Earth's centre of mass.coordonnées géocentriquesgeocentrische coördinaten
geocodingThe activity of defining the position of geographical objects relative to a standard reference grid.géocodagegeocoderen
geodesyScience studying the shape and the dimensions of the Earth.géodésiegeodesie
geodetic datumA geodetic datum is a reference object that describes the position, orientation and scale relationships of a reference ellipsoid to the Earth. A datum allows to define coordinates related to a well-defined reference frame. Modern geodetic datums are defined with respect to the center of the Earth, while historical geodetic datums are defined with respect to fundamental points on the surface of the Earth.datum géodésiquegeodetische datum
geodynamicsA branch of mechanics that deals with forces within the earth and their relation to the motion and equilibrium of the solid earth.géodynamiquegeodynamica
Geographic Information SystemA Geographic Information System (GIS) is a computerized tool designed for storing, analyzing and consulting data where geographic location is an important characteristic or critical to the analysis. It allows the mutual comparison of properly encoded spatial data, their combination with non-spatial information (e.g. statistical data) and their representation as a map.Système d'information géographiqueGeografisch Informatie Systeem
geographic reference system(georeference). The process of establishing a relationship between data in Cartesian coordinates on a flat map to known ground-truth geographic coordinates.système de référence géographiquegeografisch referentiesysteem
geographical coordinatesThe position of a localit, given in terms of latitude and longitude, relative to the equator and the prime meridian.coordonnées géographiquegeografische coördinaten
geologyThe study of the earth forming materials and their transformations in the past and the present.géologiegeologie
GeomaticsField of activity which, using a systematic approach, integrates all the means used to acquire and manage spatial data required as part of scientific, administrative, legal and technical operations involved in the process of production and management of spatial information.géomatiqueGeomatica
geometric correctionsThe removal of sensor, platform, or scene induced geometric errors such that the data conforms to a desired projection. This involves the creation of a new digital image by resampling the input digital image.corrections géométriquesgeometrische correcties
GeomorphologyThe study of the land surface features and the processes that created them.géomorphologiegeomorfologie
georeferencedDigital spatial data (and non-digital map features) for which the coordinates or location are determined. A georeferenced image is an image in wich the coordinates of each pixel are known. Georeferencing can be done using various cartographic projections.géoréferencégeoreferentie
geospatial mapOr satellite image map. Satellite image resampled in a cartographic projection, with the eventual addition of graphical elements, comments and legends, e.g. resulting from the interpretation of the image.spatiocartesatellietbeeldkaart
geostationaryA satellite orbit that stays in a fixed position relative to the surface of the Earth. Meteorological satellites usually follow a geosynchronous orbit. The satellite moves from west to east at a speed that allows it to remain over the same point on the Earth.géostationnairegeostationnair
GPSGlobal Positioning System - A network of satellites developed by the US Department of Defense. Using this system, the location of any site on the Earth's surface can be measured within several metres or centimeters (depending upon the system used).GPSGPS
greenhouse effectProcess by which significant changes in the chemical composition of the Earth's atmosphere may enhance the natural process that warms our planete and elevates temperatures.effet de serrebroeikaseffect
greenhouse gasGas capable of absorbing terrestrial radiation (i.e. radiation emitted by the earth). With respect to their influence on the climate, the main greenhouse gases are water vapour, carbon dioxide, methane, nitrous oxide and the wholly anthropogenic chlorofluorocarbons.gaz à effet de serrebroeikasgas
gridA network of regularly spaced straight lines intersecting at right angles. The raster is thus composed of cells of the same size. Each cell is assigned an integer or decimal numeric value. This structure or format is used for representing geographic information in some GIS software packages.grilleraster
grid cellA discretely uniform unit that represents a portion of the Earth. such as a square meter or square mile. Each grid cell has a value that corresponds to the feature or characteristic at that site, such as a soil type, census tract, or vegetation classcellule matriciellerastercel
Ground Control Point(GCP). Selected point referring to a certain location on the ground for which there is an accurate positional information (latitude, longitude).point de contrôle au solgrondcontrole punt
ground stationData collection, receiving or processing facilities located on the ground.station de réceptiongrondstation
heterotrophic respirationThe energy producing process of breathing, by which an organism breaks down non-living organic matter and supplies its cells with oxygen and relieves itself of carbon dioxide.respiration hétérotropheheterotrofe respiratie
histogramA graphical means of expressing the frequency distribution of pixel values in a remote sensing image. The x-axis shows the range of brightness values in the image. The height of the vertical bars are proportional to the number of pixels in the image in each class.histogrammehistogram
hydraulicPertaining to hydraulics, or the study of the dynamics of fluids, particularly water.Hydrauliquehydraulisch
HydrologyStudy of the mechanical, physical and chemical properties of oceanic and continental water.HydrologieHydrologie
HydrometeorologyThe science that combines hydrology and meteorology, with its main emphasis on the atmospheric sector of the hydrological cycle.Hydrométéorologiehydro-meteorologie
IHS-RGB fusionFusion of Intensity - Hue - Saturation and Red -Green - Blue. Method of displaying images. The IHS transformation is commonly used to merge several bands of remote sensed data, e.g. high resolution panchromatic images with low resolution multispectral images. A RGB-IHS transformation is executed on the multispectral image, the Intensity channel is replaced by the panchromatic image and the inverse transformation RGB - IHS is executed. The result is an image containing the spatial resolution of the panchromatic image and the colours of the multispectral image.fusion IHS-RGBIHS-RGB fusie
image fusionTechnique allowing to make an efficient synthesis of several information sources. There is a growing interest because of the growth in available data, particularly of remote sensed data.fusion numériquebeeldfusie
in situ measurementsField measurements. The measuring instrument is in (almost) direct contact with the object to measure.mesurages in situin situ metingen
interferometric coherence imageImage for which each pixelvalue gives the degree of correlation of two SAR images.cohérence interférométriqueinterferometrische coherentie beeld
interferometry(or phasimetrie) Combination of measuring techniques based on the information regarding the phase in radar images. The SAR technique uses the difference in phase between SAR observations of the same scene taken from slightly differeent angles. The resulting interferogramme allows to detect small changes in the Earth's surface.interférométrieinterferometrie
interpolationThe process or technique of obtaining an estimate of the value intermediate between given values.interpolationinterpolatie
isothermLine connecting points of equal temperature.isothermeisotherm
kinetic eneryEnergy of a body in motion.énergie cinétiquekinetische energie
laharWord derived from Indonesian meaning mudflow. A lahar is made up of a dense and very erosive mixture of over 50% volcanic debris and water (from precipitation, snow or glaciers,…), which is chanelled down the volcano's drainage system. This phenomenon can affect valleys around the volcano for years after an eruption.laharlahar
LambertFrench 18th century mathematician who defined several cartographic projections. In Belgium the conical Lambert projection is used.LambertLambert
landslideAn abrupt movement of soil and bedrock downhill in response to gravity. Landslides and rockslides may be initiated by heavy rains, earthquakes or by human activities.glissement de terrainaardverschuiving
lateral spreadThe lateral stretching of coherent rock or soil over an underlying deformed mass of soft material.écart latérallaterale uitdijing
lava dome A steep-sided mound that forms when viscous lava piles up near a volcanic vent. Domes are formed by andesite, dacite, and rhyolite lavasdôme de lavelavakoepel
Leaf Area Index (LAI). The total one-sided green surface of foliage per unit of soil area. LAI is an important element in remote sensing. It is used to quantify numerous biological and physical processes such as primary production, plant respiration, transpiration, photosynthesis an nutrient cycles. It is likewise of use in the detection of burnt areas.Indice de Surface Foliairebladoppervlak index
LiDARLiDAR, which stands for Light Detection and Ranging, is a remote sensing method that uses light (IR, visible or UV wavelengths) in the form of a pulsed laser to measure ranges (variable distances) to the Earth. The time needed for the light beam to reach the target and return to the transceiver is used to determine the distance between the two.  The light pulses—combined with other data recorded by the airborne system— generate precise, three-dimensional information about the shape of the Earth and its surface characteristics. A LiDAR instrument principally consists of a laser, a scanner, and a specialized GPS receiver. LiDARLiDAR
lineamentA linear (relatively straight) topographic feature or features such as a fault, line of dense vegetation, or a chain of aligned volcanoes. Can often be observed on satellite imagery.linéamentlineament
liquefactionThe process in which a granular solid (soil) takes on the characteristics of a liquid as a result of an increase in pore pressure and a reduction in stress. In other words, solid ground looses cohesion and starts flowing like a liquid.liquéfactionliquefactie
lithologyThe study and description of the general, gross physical characteristics of a rock, especially sedimentary clastics, including color, grain size, and composition.lithologielithologie
marlSedimentary rock composed of a mixture of chalck and clay.marnemergel
maskElement used to cover or delimit a zone or an area on a graphic analog document or on an image document (photograph, satellite image, ...)masquemasker
matrixA rectangular array of numeric or algebraic quantities subject to mathematical operations.matricematrix
Maximum LikelihoodClassification technique A statistical decision rule that examines the probability function of a pixel for each of the landcover classes, and assigns the pixel to the class with the highest probability.maximum de vraisemblancemaximale waarschijnlijkheid
metadatabaseMeta-data is definitional data that provides information about or documentation of other data managed within an application or environment. Meta data may include descriptive information about the context, quality and condition, or characteristics of the data.métabase de donnéesmeta-databank
meteogridGeoreferenced grid for which each cell is attributed one or more measured or calculated meteorological data.grille météometeoraster
monitoringTo watch, keep track of, or check periodically or continuously, usually for a special purpose.monitoringmonitoring
morphologyStudy of shapes and structures. Geomorphology studies the shapes in the relief.morphologiemorfologie
mosaicAn assemblage of overlapping aerial or space photographs or images whose edges have been matched to form a continuous pictorial representation of a portion of the earth surface.mosaïquemozaiek
multispectralContaining two or more spectral bands. Multispectral data: set of data acquired simultaneously but in different areas of the electromagnetic spectrum. Multispectral analysis: study of data in various spectral bands. Multispectral imagery: two or more images acquired at the same time but in different areas of the electromagnetic spectrum.multispectralmultispectraal
multitemporalImage - Colour composite, consisting of three images recorded at a different moment.multitemporellemultitemporeel
multitemporal change vector analysisAnalysis of change vectors, applied to multitemporal coverage imagery. The change vector compares for each pixel the difference in the time-trajectory of a biophysical indicator, such as the normalized difference vegetation index.analyse vectorielle multitemporellemultitemporal change vector analysis
nadir-viewingIn Nadir Mode, the line of sight of a sensor points from the orbit downward to the Earth's surface or atmosphere.observation nadirnadir observatie
Neolithic revolutionRelating to the big changes in the human way of life in the Neolitic by using natural resources (fertile soil for agriculture, vegetation and in particular wood for fuel…), man attempts to use his environment to the fullest and settles down in small settlements or villages.révolution néolithiqueNeolithische revolutie
NeoliticHistoric period starting around 10,000 years ago in the Middle East. The period is characterised by the development of agriculture and the improvement of stone toolsNéolithiqueNeolithicum
neotectonics(neo-=new, recent) Science studying recent types of movements of the earthcrust and the earth layers, e.g. recent faults, foldings, overthrust,…néotectoniqueneotektoniek
NEPNet Ecosytem Productivity, i.e. gross productivity minus autrotrophic and hetereotrophic respiration.PNE (Productivité nette de l'écosystème)NEP
Normalized Difference Vegetation IndexThe Normalized Difference Vegetation Index (NDVI), is a vegetation index and is calculated from atmospherically corrected reflectances from the visible red and near infrared channels. The resulting index value is sensitive to the presence of vegetation on the land surface.Indice de Végétation par Différence NormaliséeNormalised Difference Vegetation Index (NDVI)
NPPNet Primary Productivity, i.e. gross photosynthesis or gross primary productivity minus autotrophic respiration.PPN (Productivité primaire nette)NPP
NUTSNomenclature of territorial units for statistics. In agreement with the other Commission departments concerned, Eurostat has drawn up a nomenclature of statistical territorial units (NUTS). The current NUTS nomenclature subdivides the territory of the European Community into `Country' (or 'NUTS 0') , 'Region' ('NUTS 1),.…NUTSNUTS
occultation techniqueMeasuring stellar spectra in the UV to near-infrared range while stars are being ecplised by the Earth.technique d’occultationoccultatietechniek
optic(image, satellite, sensor). Optical system: A collection of mirrors, lens, prisms, and other devices (placed in some specified configuration) which reflect, refract, disperse, absorb, polarize, or otherwise act on light. Optical sensing: The science and techniques of using optical systems as sensors. Optical image: approximate replica of an object formed by focusing the waves that emanate from the object. The object may be self-luminescent, or it may reflect illumination from an additional source of waves.optiqueoptisch
orbitThe path described by a heavenly body in its periodic revolution. Earth satellite orbits with inclinations near 0° are called equatorial orbits because the satellite stays nearly over the equator. Orbits with inclinations near 90° are called polar orbits because the satellite crosses over (or nearly over) the north and south poles.orbiteorbit
orbital angleOr inclination. Angle between equatorial plan and the the satellite's orbital plane.angle orbitalorbitale hoek
orbital planeAn imaginary gigantic flat plate containing an Earth satellite's orbit. The orbital plane passes through the center of the Earth.plan orbitalbaanvlak
orographyPertaining to the geography of mountains.orographieorografie
orthophoto mapA map produced from a mosaic of orthophotographs, to which has been added a grid, cartographic symbology and sometimes colourorthophotoplanorthofotoplan
orthorectificationUse of photogrammetric techniques to adjust and correct for terrain displacement in images.orthorectificationorthorectificatie
ortophotographAn oblique aerial photograph that has been rectified (corrected) to remove the displacement of points caused by camera tilt and terrain relief.ortho-photographieorthofoto
ozoneOne of the several gases that make up the earth's atmosphere. It is the triatomic form of oxygen and makes up approximately one part in three million of all of the gases in the atmosphere. It is formed following the dissociation of oxygen molecules (O2) caused by the absortion of UV rays. While beneficial in the stratosphere, ozone in the troposphere is toxic for living organisms.ozoneozon
ozone layerPart of the stratosphere: zone between the tropopause (altitude between 9000 km (poles) and 18,000 km (equator) and the stratopause (50,000 km). The ozone layer protects the earth with regard to UV radiation. Analyses demonstrate a seasonal variation over Antarctica.couche d'ozoneozonlaag
panchromaticSensitive to light of all colors in the visible spectrum.panchromatiquepanchromatisch
parallaxAn apparent change in de orientation of an object, due to a change in the position of the observer.parallaxeparallax
phase shiftDifference in phase, expressed in radials, between two waves with the same frequency?déphasagedefasering
photo-interpretationThe reading and interpretation of aerial photographs and images through the quantitative and qualitative analysis of colour, contrast, texture and tone by an experiencedétationfoto-interpretatie
photogrammetryThe science of deriving the physical dimensions of objects from measurements on aerial photographsphotogrammétriefotogrammetrie
photometerAn instrument used to measure the intensity of light over a selected range of the spectrum.photomètrefotometer
photosynthesisThe manufacture by plants of carbohydrates and oxygen from carbon dioxide and water in the presence of chlorophyll with sunlight as the energy source. Oxygen and water vapor are released in the process. Photosynthesis is dependent on favorable temperature and moisture conditions as well as on the atmospheric carbon dioxide concentration.photosynthèsefotosynthese
photosynthetically active radiation(PAR); Those wavelengths in the spectrum of radiation that are effective in photosynthesis.rayonnement photosynthétiquement actiffotosynthetische actieve straling
phreatic(- eruption); An explosive volcanic eruption caused when water and heated volcanic rocks interact to produce a violent expulsion of steam and pulverized rocks. Magma is not involved.phréatiquefreatische
physiology(plant -). The organic processes and phenomena of an organism or any of its partsPhysiologiefysiologie
phytoplanctonAll photosynthetic plankton, including e.g. unicellular algae and cyanobacteria.phytoplanctonfytoplankton
pixel(pic(ture) el(ement)); area corresponding to a single element of a digital image data set.pixelpixel
pixel valueEach of the pixels that represents an image stored inside a computer has a pixel value which describes how bright that pixel is, and/or what color it should be. The digital radiation value of a pixel, expressed as a digital number (DN) or digital count (DC), radiance value, reflectance or other radiation value.valeur de pixelpixelwaarde
polarPolar orbit: orbit with inclinations near 90°. Tthe satellite crosses over (or nearly over) the north and south poles.polairepolair
Post-classificationProcedure carried out after a classification in order to improve its
ppmvParts per million by volume.ppmvppmv
Primary Data Users StationThe name for the equipment used to receive digital data from METEOSAT satellites.Primary Data Users StationPrimary Data Users Station
pyroclastic flowA hot, fast-moving and high-density mixture of fine and coarse particles and gas formed during explosive eruptions or from the collapse of a lava dome.coulées pyroclastiquespyroclastische stromen
QuaternaryCurrent geological period, characterised by the ascent and the flourishin of humanity, consists of the Pleistocene and Holocene epochs.QuaternaireKwartair
RADARRadio Detection and Ranging. A method, a system, or a technique for using beam-, reflected-, and timed electromagnetic radiation to detect, locate, and track objects, to measure distance (altitude), and to acquire terrain imagery. The term 'radar' in remote sensing terminology refers to active microwave systems (from about 1 GHz - 100 GHz; the majority of current instruments operate below 10 GHz).RADARRADAR
radiative transferThe fate of electromagnetic radiation as it is scattered, absorbed or reflected while passing through a medium.transfert radiatifstralingstransfer
radio-soundingsA electronics package attached to a balloon and carried aloft. It contains set of instruments that measure pressure, temperature, and humidity and a radio transmitter that transmits a data stream containing the information from the onboard sensor.radiosondesradiosonde
radiometric correctionsCorrections of variations in data values that are caused by sensor malfunctions and atmospheric conditions.corrections radiométriquesradiometrische correcties
real time dataRefers generally to systems that respond immediately or synchronously to external event /Data that are acquired and transmitted immediately to the ground (as opposed to playback data). Delay is limited to the actual time (propagation delays) required to transmit the datatemps réelware tijd
reflectanceRatio of the intensity of reflected radiation to that of the incident radiation on a surface.réflectancereflectantie
reflectivityRadar term referring to the ability of a radar target to return energy.réflectivitéreflectiviteit
resolutionSpatial resolution or ground resolution is the minimum (spatial) surface of a feature or minimal distance between two features in order for a sensor to be able to discriminate them. Spectral resolution: The ability of a sensing system to resolve or differentiate electromagnetic radiations of different frequencies. Spectral and radiometric resolutions refer to the resolving power of a system in wavelength and energy, respectively. Temporal resolution: The frequency (in time) of remote sensing imaging possible with a particular sensor.résolutionresolutie
rockfallThe sudden fall of one or more large pieces of a rock from a cliff.écroulementafstorting
RUERadiation Use EfficiencyRUERUE
scannerA device that examines an area or region point by point in a continuous systematic manner, repeatedly sweeping across until the entire area or region is covered.scanner (balayeur)scanner
secantA straight line that cuts a curve or surface at two or more points. Secants are used in the construction of some geometric map projections.sécantesecans
SecundaryMesozoic: geological era following the Paleozoic era and divided into the Triassic, Jurassic and Cretaceous periods.SecondaireSecundair
seepage lineThe uppermost level at which flowing water emerges along a seepage face Seepage face - A boundary between the saturated flow field and the atmosphere along which ground water discharges, either by evaporation or movement "downhill" along the land surface or in a well as a thin film in response to the force of de suintementzijpzone
semi-arid(Semi-desert) areas with a semi-arid environment (climate) are characterised by a dry season lasting the major part of the year and minimal rainfall during the "wet" season.semi-aridesemi-aried
shedShelter protecting game for bad weather, predators and human beings.remiseschuilhut
sidelapThe area common to two consecutive photos/images. The amount is expressed as a percentage of the total photo area.recouvrementlongitudinale overlapping
sleeping sicknessInfection from the flagellate protozoan Trypanosoma brucei gambiense or the closely related subspecies T. brucei rhodesiense, transmitted by the tsetse fly. Sleeping sickness is characterized by fever and inflammation of the lymph nodes.maladie du sommeilslaapziekte
sondeDevice for testing physical conditions.sondesonde
spatial dataData, usually stored as coordinates, that describe the location, shape, and spatial relationships of geographic features.données spatialesgespatialiseerd (spatialisatie)
spectral bandA finite segment of wavelengths in the electromagnetic spectrum.bande spectralespectrale band
spectral signatureThe frequency distribution patterns of radiation reflected and/or emitted by an object.signature spectralespectrale signatuur
spectrophotometerA device for measuring the relative amounts of radiant energy or radiant flux as a function of wavelength.spectrophotomètrespectrofotometer
spectroradiometerRadiometer for carrying out measurements in a large number of small wavelength bands.spectroradiomètrespectroradiometer
spruce standStand of trees of the genus (Picea, evergreen trees of the pine family with a conical head of dense foliage and soft light wood.pessièresparrenbos
static slope failureSlope failure (landslide, mudflow, rock slide,…) in static conditions, without external ground shaking, as opposed to dynamic slope failure where the rupture is triggered by an earthquake. The static slope failure can be triggered by heavy rains, storms, erosion or anthropic activities.rupture de talus statiquesstatische grondverzakking
stereomicrometerDevice to determine the height (and relative difference in height) of an object on an aerial photograph based on the reading of radial image displacement.stéréomicromètrestereomicrometer
stereomodelA stereoscopic model is a 3-dimensional optical image produced by combining the images from two overlapping aerial photographs, or other remotely sensed imagery (taken at slightly different angles) of the same area.modèle stéréoscopiquestereomodel
stereoscopicA science that deals with stereoscopic effects and methods of seeing overlapping twodimensional images in three dimensions. The area of overlap is called the stereoscopic overlap area. The pair of photographs is called a stereopair.stéréoscopiestereoscopisch
stratificationStructure produced by deposition of sediments in layers or beds.stratificationgelaagdheid / stratificatie
stratigraphyThe study of the character, form, and sequence of layered rocks.stratigraphiestratigrafie

Region of the atmosphere between the troposphere and mesosphere, having a lower boundary of approximately 8 km at the poles to 15 km at the equator and an upper boundary of approximately 50 km. The stratosphere contains 90% of atmospheric ozone (O3).

stratovolcanoA steep-sided volcano composed of many layers of volcanic rocks, usually of high-viscosity lava and fragmented debris such as lahar and pyroclastic deposits.strato-volcanstratovulkaan
suitability of the siteAptitude of an environment to meet the requirements of a species for development and survival.bonité du sitegeschiktheid van een site
sunsynchronousAn earth satellite orbit in which the orbital plane is near polar and the altitude is such that a satellite will always pass over a specific place on earth at the same local sun time and at fixed time intervals.héliosynchronezonsynchroon
sustainable developmentA concept that has emerged in recent years, based on the premise that development must meet the need of the present generation without compromising the ability of future generations to meet their own needs.développement durableduurzame ontwikkeling
synoptic viewObservation of parameters over a distance spanning a continent.vue synoptiquesynoptische waarneming
tandemIn 1996, the ERS-1 and ERS-2 satellites started flying in tandem, meaning that ERS-2 is following ERS-1 in the same orbit with a 24 h time interval.tandemtandem
tangentA mathematical term used in the construction of some geometric map projections describing a straight line or plane surface touching a curved line or curved surface at a single point but not intersecting it.tangentetangente
tectonicThose major processes within the crust of the earth that lead to its structural deformation.tectoniquetektoniek
ten-day synthesis productsProduct compiled from daily synthesis over the previous ten days. The synthesis is delivered in a standard map projection.produit de synthèse décadairetiendaagse synthese produkten
tephraSolid material of all sizes explosively ejected from a volcano into the atmosphere.tephratephra
textureThe visual or tactile surface characteristics and appearance of an object.texturetextuur
thalwegRiver profile.thalwegthalweg
thematic mapMap representing the disitribution, nature and/or quantity of certain (groups of) phenomena of topics on a topographic background.carte thématiquethematische kaart
time seriesAny series of observations of a physical variable that is sampled at (changing) time intervals.série temporelletijdsreeks
tomographyRadiologic technique for determining physical characteristics of predetermined plane sections of a solid object (a rock massive or soil in the present case) based on surface measurements at various spots.tomographietomografie
topographic factorThis factor forms part of the Universal Soil Loss Equation - USLE. For convenience, the slope length factor L and slope steepness factor S are frequently conjoined into a single topographic factor LS because the effect of steeper slopes and longer slopes is similar. Steeper slopes produce higher overland flow velocities. Longer slopes accumulate runoff from larger areas and also result in higher flow velocities. Thus, both result in increased erosion potential, but in a non - linear manner.facteur topographiquetopografische factor LS
topographic mapMap representing the topography according to preset criteria, providing the required accuracy and comprehensiveness for orientation and terrain study.carte topographiquetopografische kaart
topographyThe configuration or shape of features on the Earth's land surface. Topography is depicted on maps by contour lines, hypsometric tints, and relief shading.topographietopografie
topologyA term that defines the spatial relationships between features(points, lines and surfaces) in a vector layer (touching lines, little surfaces enclosed in bigger surfaces,…). Topological relationships are useful in GIS, because spatial analyses often occur in absence of geographical coordinates.topologietopologie
toponymyTaxonomic study of place-names, based on etymological, historical, and geographical information.toponymietoponomie
transmittanceThe ratio of energy transmitted by a body to that incident on it.transmittancetransmissie

A mineral consisting of a massive usually layered calcium carbonate (as aragonite or calcite) formed by deposition from spring waters, especially from hot springs, and shallow waters with small rapids. The precipitation of carbonates is provoked by turbulence, and the loss of CO2.

triangulationAn accurate method of surveying based on the geometric principle that if the measurements of one side and two angles of a triangle are known then the other dimensions of the triangle can be calculated. Starting with a known base line, a network of known horizontal positions on the Earth's surface may be established by expanding a network of triangles, for once the other sides of the first triangle are calculated then one of them can be used as the base line for the next triangle. This process establishes horizontal control.triangulationtriangulatie
troposphereBottom layer of the atmosphere.troposphèretroposfeer
turbidity indexMeasure of the turbidity of water. Turbidity: A cloudy condition in water due to suspended silt or organic matter.index de turbiditéturbiditeitsindex
Universal Soil Loss Equation(USLE). Equation providing techniques for prediction of average annual soil loss caused by sheet and rill erosion. USLE = A = R K LS P C with A = Annual soil loss; R = Rainfall factor; K = Soil erodibility factor; L = Field slope length factor; S = Field slope factor; (LS = Topographic factor); C = Cropping factor; P = Conservation practice factor (e.g. influence of terraces) C = cropping factorUniversal Soil Loss EquationUniversal Soil Loss Equation
URBISURBIS is a administrative, digital map reproducing the green areas of the Brussels regio.URBISURBIS
validationTo validate: to support or corroborate on a sound or authoritative basis.validationvalideren
vector dataThe representation of spatial data using points, lines, and polygons, digitally encoded according to their origins, breakpoints and terminators.données vectoriellesvector(gegevens)
vector maskMask defined by its vector outline.masque vectorielvectoriëel masker
vegetation indexThe reduction of multispectral scanning measurements to a single value for predicting and assessing vegetative characteristics such as plant leaf area, total biomass and general plant stress and vigor. In general, measurements from the red and infrared area of the electromagnetic spectrum are used for the calculation of vegetation indices because of the specific spectral signature of plants .indice de végétationvegetatie-index
viscosityResistance of a fluid (liquid or gas) to a change in shape, or movement of neighbouring portions relative to one another.viscositéviscositeit
visible lightElectromagnetic radiation with a wavelength between 400 and 750 nm, limited by the ultraviolet and the infrared channel.lumière visiblezichtbaar licht
wadiSeasonal river in arid areas.ouedwadi
water cycleHydrological cycle. A complex group of processes by which water in its various forms is circulated through the earth/atmosphere system. It is powered by solar radiation which provides the energy to maintain the flow through such processes as evaporation, transpiration, precipitation and runoff.cycle de l'eauwatercyclus
wetlandArea habitually saturated with water, which may be partly or wholly covered permanently, occasionally or periodically by fresh or salt water up to a depth of 6 m and that includes bogs, fens, water meadows, marshland and salt marshes, shallow ponds, river estuaries and intertidal mud flats, but excludes rivers, streams, lakes and oceans.milieu humidewaterrijk gebied - wetland
whitecapA wave crest breaking into white foam.écumeschuimkop