5. Codelists

5.1. EPSG Registry

Refer to the official EPSG Geodetic Parameter Dataset of coordinate reference systems and transformations. Refer to https://www.epsg-registry.org/ for further details.

5.2. MD_MetadataScopeCode

A reduced version of MD_ScopeCode.

Element name	Element description
dataset	information applies to the dataset
series	information applies to the entire dataset series
nonGeographicDataset	information applies to only non-geographic data
software	information applies to a computer program or routine
model	information applies to a copy or imitation of an existing or hypothetical object
initiative	information applies to an initiative
sample	information applies to a single sample
aggregate	information applies to an aggregate resource

5.3. MD_ProgressCode

Element name	Element description
completed	production of the data has been completed
historicalArchive	data has been stored in an offline storage facility
obsolete	data is no longer relevant
onGoing	data is continually being updated
planned	fixed date has been established upon or by which the data will be created or updated
required	data needs to be generated or updated
underDevelopment	data is currently in the process of being created
final	progress concluded and no changes will be accepted
pending	committed to, but not yet addressed
retired	item is no longer recommended for use. It has not been superseded by another item
superseded	replaced by new document
tentative	provisional changes likely before resource becomes final or complete
valid	acceptable under specific conditions
accepted	agreed to by sponsor
notAccepted	rejected by sponsor
withdrawn	removed from consideration (generally implies data problems beyond obsolence)
proposed	suggested that development needs to be undertaken
deprecated	resource superseded and will become obsolete, use only for historical purposes

5.4. ISO 639-2 three letter language code

Refer to this Library of Congress page on ISO 639-2 for a complete list sorted by English language name, and to this page for a list sorted by the three letter code.

5.5. ISO 3166-1 three letter country code

Refer to the Wikipedia page on ISO 3166-1 alpha-3 for a list of current 3166-1 three letter country codes.

5.6. MD_CharacterSetCode

Element name	Element description
ucs2	16-bit fixed size Universal Character Set, based on ISO/IEC 10646
ucs4	32-bit fixed size Universal Character Set, based on ISO/IEC 10646
utf7	7-bit variable size UCS Transfer Format, based on ISO/IEC 10646
utf8	8-bit variable size UCS Transfer Format, based on ISO/IEC 10646. The default.
utf16	16-bit variable size UCS Transfer Format, based on ISO/IEC 10646
8859part1	ISO/IEC 8859-1, Information technology - 8-bit single byte coded graphic character sets - Part 1 : Latin alphabet No.1
8859part2	ISO/IEC 8859-2, Information technology - 8-bit single byte coded graphic character sets - Part 2 : Latin alphabet No.2
8859part3	ISO/IEC 8859-3, Information technology - 8-bit single byte coded graphic character sets - Part 3 : Latin alphabet No.3
8859part4	ISO/IEC 8859-4, Information technology - 8-bit single byte coded graphic character sets - Part 4 : Latin alphabet No.4
8859part5	ISO/IEC 8859-5, Information technology - 8-bit single byte coded graphic character sets - Part 5 : Latin/Cyrillic alphabet
8859part6	ISO/IEC 8859-6, Information technology - 8-bit single byte coded graphic character sets - Part 6 : Latin/Arabic alphabet
8859part7	ISO/IEC 8859-7, Information technology - 8-bit single byte coded graphic character sets - Part 7 : Latin/Greek alphabet
8859part8	ISO/IEC 8859-8, Information technology - 8-bit single byte coded graphic character sets - Part 8 : Latin/Hebrew alphabet
8859part9	ISO/IEC 8859-9, Information technology - 8-bit single byte coded graphic character sets - Part 9 : Latin alphabet No.5
8859part10	ISO/IEC 8859-10, Information technology - 8-bit single byte coded graphic character sets - Part 10 : Latin alphabet No.6
8859part11	ISO/IEC 8859-11, Information technology - 8-bit single byte coded graphic character sets - Part 11 : Latin/Thai alphabet
8859part13	ISO/IEC 8859-13, Information technology - 8-bit single byte coded graphic character sets - Part 13 : Latin alphabet No.7
8859part14	ISO/IEC 8859-14, Information technology - 8-bit single byte coded graphic character sets - Part 14 : Latin alphabet No.8 (Celtic)
8859part15	ISO/IEC 8859-15, Information technology - 8-bit single byte coded graphic character sets - Part 15 : Latin alphabet No.9
8859part16	ISO/IEC 8859-16, Information technology - 8-bit single byte coded graphic character sets - Part 16 : Latin alphabet No.10
jis	Japanese code set used for electronic transmission
shiftJIS	Japanese code set used on MS-DOS machines
eucJP	Japanese code set used on UNIX based machines
usAscii	United States ASCII code set (ISO 646 US)
ebcdic	IBM mainframe code set
eucKR	Korean code set
big5	traditional Chinese code set used in Taiwan, Hong Kong of China and other areas
GB2312	simplified Chinese code set
Windows-1252	Windows-specific extension of ISO/IEC 8859-1. Includes additional special characters.

5.7. MD_CoverageContentTypeCode

Element name	Element description
image	meaningful numerical representation of a physical parameter that is not the actual value of the physical parameter
thematicClassification	code value with no quantitative meaning, used to represent a physical quantity
physicalMeasurement	value in physical units of the quantity being measured

5.8. MD_TopicCategoryCode

Element name	Element description
farming	rearing of animals and/or cultivation of plants. Examples: agriculture, irrigation, aquaculture, plantations, herding, pests and diseases affecting crops and livestock
biota	flora and/or fauna in natural environment. Examples: wildlife, vegetation, biological sciences, ecology, wilderness, sealife, wetlands, habitat
boundaries	legal land descriptions. Examples: political and administrative boundaries
climatologyMeteorologyAtmosphere	processes and phenomena of the atmosphere. Examples: cloud cover, weather, climate, atmospheric conditions, climate change, precipitation
economy	economic activities, conditions and employment. Examples: production, labour, revenue, commerce, industry, tourism and ecotourism, forestry, fisheries, commercial or subsistence hunting, exploration and exploitation of resources such as minerals, oil and gas
elevation	height above or below sea level. Examples: altitude, bathymetry, digital elevation models, slope, derived products
environment	environmental resources, protection and conservation. Examples: environmental pollution, waste storage and treatment, environmental impact assessment, monitoring environmental risk, nature reserves, landscape
geoscientificInformation	information pertaining to earth sciences. Examples: geophysical features and processes, geology, minerals, sciences dealing with the composition, structure and origin of the earth’s rocks, risks of earthquakes, volcanic activity, landslides, gravity information, soils, permafrost, hydrogeology, erosion
health	health, health services, human ecology, and safety. Examples: disease and illness, factors affecting health, hygiene, substance abuse, mental and physical health, health services
imageryBaseMapsEarthCover	base maps. Examples: land cover, topographic maps, imagery, unclassified images, annotations
intelligenceMilitary	military bases, structures, activities. Examples: barracks, training grounds, military transportation, information collection
inlandWaters	inland water features, drainage systems and their characteristics. Examples: rivers and glaciers, salt lakes, water utilization plans, dams, currents, floods, water quality, hydrographic charts
location	positional information and services. Examples: addresses, geodetic networks, control points, postal zones and services, place names
oceans	features and characteristics of salt water bodies (excluding inland waters). Examples: tides, tidal waves, coastal information, reefs.
planningCadastre	information used for appropriate actions for future use of the land. Examples: land use maps, zoning maps, cadastral surveys, land ownership
society	characteristics of society and cultures. Examples: settlements, anthropology, archaeology, education, traditional beliefs, manners and customs, demographic data, recreational areas and activities, social impact assessments, crime and justice, census information
structure	man-made construction. Examples: buildings, museums, churches, factories, housing, monuments, shops, towers
transportation	means and aids for conveying persons and/or goods. Examples: roads, airports/airstrips, shipping routes, tunnels, nautical charts, vehicle or vessel location, aeronautical charts, railways
utilitiesCommunication	energy, water and waste systems and communications infrastructure and services. Examples: hydroelectricity, geothermal, solar and nuclear sources of energy, water purification and distribution, sewage collection and disposal, electricity and gas distribution, data communication, telecommunication, radio, communication networks
extraTerrestrial	region more than 100 km above the surface of the Earth
disaster	Information related to disasters. Examples: site of the disaster, evacuation zone, disaster-prevention facility, disaster relief activities

5.9. SeaVoX platform types

Element name	Element description
Unknown	The correct value is not known to, and not computable by, the creator of this information. However, a correct value probably exists.
Land or seafloor	A platform located on the solid surface of the Earth either above or below sea level.
Fixed benthic node	A collection of oceanographic instruments mounted at a fixed position on the seabed (e.g. POL Monitoring Platform, seabed ADCP).
Sea bed vehicle	An instrumented platform that is propelled on wheels or tracks on the seabed (e.g benthic crawler).
Beach/intertidal zone structure	A structure to which instrumentation may be attached that is either in air or under water depending on the state of the tide and weather conditions.
Land/onshore structure	A fixed man-made structure on land to which instrumentation may be attached (e.g. meteorological tower).
Land/onshore vehicle	An instrumented vehicle or sample collector that operates on the solid surface of the Earth (e.g. mobile meteorological station, land crawler, snowmobile).
Offshore structure	A fixed (for the duration of the measurements) man-made structure away from the coast to which instrumentation may be attached (e.g. oil rig, gas rig or jack-up barge).
Coastal structure	A fixed man-made structure permanently linked to land with access to water at all states of the tide to which instrumentation may be attached (e.g. pier).
River station	An instrumented structure in a river upstream of its tidal limit.
Mesocosm bag	A large polythene bag containing a water sample suspended in the natural environment so that it shares ambient physical conditions such as temperature and light levels, but is chemically isolated to allow experiments such as fertilization.
Submersible	A platform operating within a water body.
Propelled manned submersible	A platform operating in the water column that has both self-contained propulsion and at least one human operator on board (e.g. submarine).
Propelled unmanned submersible	A platform operating in the water column attached to a mothership by an umbilical with limited propulsion and no human operator on board (e.g. ROV).
Towed unmanned submersible	A vehicle towed by rigid cable through the water column at fixed or varying depth with no propulsion and no human operator (e.g. Towfish, Scanfish, UOR, SeaSoar).
Drifting manned submersible	A platform operating in the water column attached to a mothership by an umbilical but with no means of propulsion that has at least one human operator on board (e.g. bathysphere).
Autonomous underwater submersible	A free-roving platform operating in the water column with propulsion but no human operator on board (e.g. Autosub, Glider).
Lowered unmanned submersible	An unmanned platform lowered and raised vertically by a cable from the mothership. Includes any type of profiling sensor mounting such as CTD frames, profiling radiometers and instrumented nets.
Sub-surface gliders	Platforms with buoyancy-based propulsion that are capable of operations at variable depths which are not constrained to be near the sea surface.
Ship	A large platform operating on the surface of the water column. Objective definitions for guidelines: >50m length (EU), >100 foot length (USA), >300 GRT weight (SOLAS). Subjective definition: a ship is a vessel big enough to carry a boat.
Research vessel	A platform of any size operating on the surface of the water column in unpredictable locations that is specifically equipped, manned and operated for scientific, usually oceanographic, research.
Vessel of opportunity	A platform for purpose of commerce of any size operating on the surface of the water column in unpredictable locations that regularly collects scientific (oceanographic and meteorological) data (e.g. an instrumented cargo vessel).
Self-propelled small boat	A small self-propelled platform operating on the surface of the water column that may be easily removed from the water (e.g. shore-based RIBs, ships’ boats).
Vessel at fixed position	A platform of any size occupying a fixed location on the surface of the water column for prolonged periods collecting scientific (oceanographic and meteorological) data as a primary or secondary mission. Includes light vessels and weather ships.
Vessel of opportunity on fixed route	A platform repeatedly following a predictable fixed track on the surface of the water column that collects scientific (oceanographic and meteorological) data (e.g. an instrumented ferry).
Fishing vessel	A platform operating on the surface of the water column whose primary purpose is the commercial harvesting of fish or shellfish but may be engaged in scientific activities such as fish stock surveys or mooring deployments and recoveries.
Self-propelled boat	A small self-propelled platform operating on the surface of the water column in unpredictable locations that is smaller than a ship, but too large to easily remove from the water.
Man-powered boat	A platform operating on the surface of the water column that is manually propelled and may not be easily removed from the water (e.g. trireme).
Naval vessel	A platform operating on the surface of the water column in unpredictable locations that is primarily equipped, manned and operated for military purposes. Includes surface warships of all sizes and logistic support vessels.
Man-powered small boat	A platform operating on the surface of the water column that is manually propelled and may be easily removed from the water (e.g. rowing boat, canoe).
Autonomous surface water vehicle	A self-propelled vehicle operating on the sea surface with no human occupants.
Surface gliders	Platforms operating at a single depth near the sea surface, using a combination of solar energy and wave motion as means of propulsion.
Drillship	A drillship is a merchant vessel designed for use in exploratory offshore drilling of new oil and gas wells or for scientific drilling purposes.
Surface vessel	A mobile platform with propulsion operating on and restricted to the surface of a water body.
Moored surface buoy	An unmanned instrumented platform operating on the surface of the water column loosely tethered to the seafloor to maintain a fixed position (e.g. ODAS buoy).
Drifting surface float	An unmanned instrumented platform operating on the surface of the water column often attached to a drogue to track currents rather than winds (e.g. Argos buoy).
Subsurface mooring	A collection of oceanographic instruments attached to wires suspended between anchors on the seabed and buoyant spheres in the water column.
Drifting subsurface float	An unmanned instrumented platform drifting freely in the water column at a depth governed by its density (e.g. Swallow float).
Fixed subsurface vertical profiler	A platform that periodically makes an automated vertical traverse of the water column at a predetermined fixed location. (e.g. YSI vertical profiler, HOMER CTD).
Drifting subsurface profiling float	An unmanned instrumented platform drifting freely in the water column that periodically makes vertical traverses through the water column (e.g. Argo float).
Float	A free-floating platform either on the surface of the water column or at a predetermined depth within the water column.
Mooring	A tethered collection of oceanographic instruments at a fixed location that may include seafloor, mid-water and surface components.
Surface ice buoy	An undrogued (i.e. no sub-surface parachute) surface float that is deployed in regions where sea ice forms that moves with either ice or water depending upon the time of year.
Buoyant aircraft	A platform capable of flight in the atmosphere because it is lighter than air.
Free-rising balloon	A container filled with a gas that is lighter than air, which is constrained to rise vertically at a fixed location.
Free-floating balloon	A container filled with a gas that is lighter than air, which is free to drift in the atmosphere.
Tethered balloon	A container filled with a gas that is lighter than air, which is tethered at a fixed height and location.
Airship	A self-propelled container filled with a gas that is lighter than air.
Non-buoyant aircraft	A platform capable of flight in the atmosphere despite its being heavier than air.
Research aeroplane	A fixed-wing self-propelled aircraft that is equipped, manned and operated for atmospheric, meteorological or oceanographic research.
Aeroplane	A fixed-wing self-propelled aircraft.
Rocket	A rocket is a vehicle, missile or aircraft which obtains thrust by the reaction to the ejection of fast moving exhaust gas from within a rocket engine.
Geostationary orbiting satellite	A vehicle operating beyond the Earth’s atmosphere without human occupants that orbits the Earth at the same rate as the Earth’s rotation keeping it over a fixed location on the Earth’s surface.
Orbiting satellite	A vehicle operating beyond the Earth’s atmosphere without human occupants that orbits the Earth at a different rate to the Earth’s rotation so it moves over the Earth’s surface.
Manned spacecraft	A vehicle operating beyond the Earth’s atmosphere with human occupants.
Helicopter	An aircraft without wings that obtains its lift from the rotation of overhead blades.
Satellite	A vehicle operating beyond the Earth’s atmosphere without human occupants that orbits the Earth.
Autogyro	An aircraft without wings that obtains its lift from the rotation of overhead blades, but obtains forward populsion from a fixed propellor.
Glider	A fixed-wing aircraft with no propulsion.
Kite	An aerofoil tethered to the ground held aloft by the wind.
Parachute	A fabric sheet designed to slow the descent of an object through the atmosphere.
Unmanned aerial vehicle	Any untethered heavier-than-air aircraft that is not occupied by people: may be a remotely piloted aircraft or an autonomous aircraft. Also referred to as a drone.
Spacecraft	A platform operating beyond the Earth’s atmosphere.
Organism	A living creature carrying instruments or collecting samples.
Human	A human being without specialised equipment operating on land or the surface of the water column.
Diver	A human being with self-contained equipment or surface-connected suit enabling operation within the water column.
Flightless bird	A bird that is unable to fly with the ability to exist within the water column (e.g. penguin).
Seabird and duck	A flighted bird that is able to exist on the water column surface and dive into the water column (e.g. cormorants, auks, ducks and gulls).
Cetacean	A mammal that exists within the water column but needing to regularly surface to breathe (i.e. dolphins and whales).
Fish	A free-swimming creature that exists totally within the water column.
Land-sea mammals	A mammal that exists both on land and within the water column. Includes seals, sea-lions, sea-otters and walruses.
Cryosphere	A frozen body of water on land, freshwater or sea.
Ice island	A floating ice sheet detached from the coast.
Ice shelf	A floating ice sheet attached to the coast.
Pack ice	Sea ice not connected to land with an ice concentration of over 70 per cent.
Drift ice	Sea ice not connected to land with an ice concentration of under 70 per cent.
Amphibious vehicle	A self-propelled platform capable of operating on land and within or on the surface of a water body.
Amphibious crawler	A self-propelled vehicle capable of operation on land or the seabed (e.g. beach crawler).
DUKW	A six-wheel drive amphibious truck developed during the second World War.
Hovercraft	A craft capable of moving over water or land on a downwardly-propelled cushion of air.

5.10. Acoustic experimental parameters

Element name	Element description
Sound pressure	The difference between instantaneous total pressure and pressure that would exist in the absence of sound. This is in effect the quantity that is being represented when a sound pressure waveform is plotted.
Peak sound pressure	The maximum sound pressure during a stated time interval. A peak sound pressure may arise from a positive or negative sound pressure. This quantity is typically useful as a metric for a pulsed waveform, though it may also be used to describe a periodic waveform.
Peak compressional pressure	The maximum value of the magnitude of the compressional pressure during a stated time interval. Peak compressional pressure is sometimes referred to as “peak-positive sound pressure”. A peak compressional pressure may only arise from a positive sound pressure. This quantity is typically most useful as a metric for a pulsed waveform, though it may also be used to describe a periodic waveform.
Peak rarefactional pressure	The maximum value of the magnitude of the rarefactional pressure during a stated time interval. Peak rarefactional pressure is sometimes referred to as “peak-negative sound pressure”. A peak rarefactional pressure may only arise from a negative sound pressure, but is expressed as a positive valued quantity. This quantity is typically most useful as a metric for a pulsed waveform, though it may also be used to describe a periodic waveform.
Peak to peak sound pressure	The sum of the peak compressional pressure and the peak rarefactional pressure during a stated time interval. This quantity is typically most useful as a metric for a pulsed waveform, though it may also be used to describe a periodic waveform.
RMS sound pressure	The square root of the mean square pressure, where the mean square pressure is the time integral of squared sound pressure over a specified time interval divided by the duration of the time interval. The RMS sound pressure is calculated by first squaring the values of sound pressure, averaging over the specified time interval, and then taking the square root. The averaging time must always be stated.
Sound exposure	The integral of the square of the sound pressure over a stated time interval or event (such as an acoustic pulse). As the integral of squared sound pressure over time, the quantity is sometimes called the “pressure-squared integral”. The quantity is sometimes taken as a proxy for the energy content of the sound wave (it may be converted to energy flux density by dividing by the specific acoustic impedance of the medium). When applied to an acoustic pulse, the integration time is the pulse duration. When applied to a single pulse (or event), the quantity is sometimes called “single pulse sound exposure” (or “single event sound exposure”). Note that the sound exposure useful as a measure of the exposure of a receptor to a sound field, and a frequency weighting is commonly applied. If a frequency weighting is applied, this should be indicated by appropriate subscripts.
Cumulative sound exposure	The sound exposure determined for an extended period or sequence of pulses/events.When stating the cumulative sound exposure, it is important to specify any other relevant information such number of pulses, total time duration, duty cycle of any sampling, etc. A more detailed discussion is provided in Section 2.3.
Pulse duration	The time during which a specified percentage of sound energy in the signal occurs. In the calculation, sound exposure may be used as a proxy for energy. A typical value of the percentage taken is 90, so that the duration is the time window during which 90% of the energy is present. This metric is intended for use to describe pulsed signals. If the percentage is represented by X, the metric is typically calculated by starting at (50-X/2)% and ending at (50+X/2)% of total energy (or 5% to 95% when X = 90).Note that this definition covers only X% of the overall pulse; if it is necessary to account for all time (or energy) in the pulse (including the “missing” 10% in the example given), multiply the above value by 100/X.
Pulse repetition frequency	The number of pulses or events arriving per second. Note that this is not the same as the number of cycles of signal arriving per second (the acoustic frequency).
Spectral density	Any quantity expressed as a contribution per unit of bandwidth.An example is sound exposure spectral density, expressed in units of Pa2·s/Hz.
Sound particle displacement	The instantaneous displacement in a stated direction of a particle in a medium from its position in the absence of sound waves.
Sound particle velocity	The instantaneous velocity of a material particle in a stated direction due to the action of sound waves. The sound particle velocity is equal to the rate of change with time of the acoustic particle displacement in a stated direction.
Sound particle acceleration	The instantaneous acceleration of a material particle in a stated direction due to the action of sound waves.
Mean square sound pressure	The product of the sound pressure and the particle velocity at a point in the sound field. Sound intensity is a vector quantity and is expressed for a specific direction
Instantaneous sound intensity	The product of the sound pressure and the particle velocity at a point in the sound field. Sound intensity is a vector quantity and is expressed for a specific direction.
Time-averaged sound intensity	The time-average of the sound intensity over a stated time interval in a stated direction. It is a vector quantity and is expressed for a specific direction.
Sound energy flux density	The time-integrated sound intensity at a far-field measurement position in a stated direction.
Sound power	The sound power is the sound intensity integrated over a closed surface surrounding a source. It is the rate of sound energy radiated by a source.
Source factor	The source factor is the product of the far-field acoustic pressure and the distance from the source in a stated direction in the acoustic far-field.
Acoustic pulse rise time	The time required for the sound pressure to rise from X% to Y% of its maximum value, with 5% and 95% typically chosen for values of X and Y respectively.
Compressional pressure	sound pressure, p(t), when p(t) > 0, where t is time
Rarefactional pressure	magnitude of sound pressure, |p(t)|, when p(t) < 0, where p is sound pressure and t is time
Sound exposure spectral density	distribution as a function of non-negative frequency of the time-integrated squared sound pressure per unit bandwidth of a sound having a continuous spectrum
Equivalent plane wave sound intensity	mean-square sound pressure, mml_m22, divided by the product of the density, ρ, and sound speed, c, of the undisturbed fluid
Mean-square sound pressure spectral density	distribution as a function of non-negative frequency of the mean-square sound pressure per unit bandwidth of a sound having a continuous spectrum
Force impulse	integral of a transient force, over a specified time interval or event, for a specified frequency range
Pressure impulse	integral of a transient sound pressure , p(t), over a specified time interval or event, for a specified frequency range
Sound pressure variance	variance of the sound pressure, p(t), over a specified time interval, t1 to t2, for a specified frequency range
Sound pressure skewness	skewness of the sound pressure, p(t), over a specified time interval, t1 to t2, for a specified frequency range
Sound pressure kurtosis	kurtosis of the sound pressure, p(t), over a specified time interval, t1 to t2, for a specified frequency range
Characteristic acoustic impedance	sound pressure divided by the component of the sound particle velocity in the direction of the wave propagation, at a point in a non-dissipative medium and for a plane progressive wave
Specific acoustic impedance	Fourier transform of sound pressure, P(f), divided by the Fourier transform of sound particle velocity in a given direction, U(f)
Sound exposure source factor	product of the square of the distance from the acoustic centre (3.3.1.3) of a source, in a specified direction, r2, and time-integrated squared sound pressure (3.1.3.5) in the acoustic far field (3.3.1.1) at that distance, Ep(r), of a sound source, if placed in a hypothetical infinite uniform lossless medium of the same density and sound speed as the real medium at the location of the source, with identical motion of all acoustically active surfaces as the true source in the true medium
Source waveform	The sound waveform of the source, measured as an intensity or pressure as a function of time
Source spectrum	The sound spectrum of the source, created by Fourier transforming the source waveform. Expressed as an intensity or pressure as a function of frequency
Propagation factor	mean-square sound pressure divided by the source factor in a specified direction
Sound exposure propagation factor	time-integrated squared sound pressure divided by the sound exposure source factor in a specified direction
Transmission loss	reduction in a specified level between two specified points x1, x2 that are within an underwater acoustic field
Propagation loss	difference between source level in a specified direction, LS, and mean-square sound pressure level, Lp(x), at a specified position, x
Sound exposure propagation loss	difference between sound exposure source level in a specified direction, LS,E, and time-integrated squared sound pressure level, LE,p(x), at a specified position, x</description>
Differential scattering cross section	quotient of the ensemble-average of the free-field time-averaged sound power radiated per unit solid angle in a specified direction in the far field of the scattered field by the magnitude of the time-averaged sound intensity of the incident field, for an incident plane wave and specified continuous incident signal
Total scattering cross section	differential scattering cross section, σΩ, of an object, integrated over all solid angles with respect to the scattering direction
Absorption cross section	quotient of the ensemble-average of the free-field time-averaged rate at which sound energy is converted to heat by the time-averaged sound intensity of the incident field, for an incident plane wave
Extinction cross section	quotient of the mean rate of work done on a scatterer by the magnitude of the time-averaged sound intensity of the incident field, for an incident plane wave
Volume differential scattering cross section per unit volume	quotient of the ensemble-average of the free-field time-averaged sound power radiated per unit solid angle in a specified direction in the far field of the scattered field per unit volume of water by the time-averaged sound intensity of the incident field, for an incident plane wave
Sea surface differential scattering per unit area	ratio of the ensemble-average of the free-field time-averaged sound power radiated per unit solid angle in a specified direction in the far field of the scattered field per unit area of sea surface to the time-averaged sound intensity of the incident field, for an incident plane wave
Sea bottom differential scattering per unit area	ratio of the ensemble-average of the free-field time-averaged sound power radiated per unit solid angle in a specified direction in the far field of the scattered field per unit area of sea bottom to the time-averaged sound intensity of the incident field, for an incident plane wave
Effective signal duration	square of the integral with respect to time of |μ(t)|2 divided by the integral with respect to time of |μ(t)|4, where μ(t) is the complex envelope of the sound pressure
Threshold exceedance signal duration	time during which the mean-square sound pressure level (SPL) exceeds a specified threshold y decibels below the maximum SPL, for a specified averaging time
Percentage energy signal duration	time during which a specified percentage x of time-integrated squared sound pressure occurs, starting at (50 - x/2) % and ending at (50 + x/2) % of total energy
Effective signal bandwidth	square of the integral with respect to frequency of |M(f)|2 divided by the integral with respect to frequency of |M(f)|4, where M(f) is the Fourier transform of the complex envelope, μ(t), corresponding to a time-dependent field quantity, p(t)
Sonar signal sound pressure	sound pressure at a specified position caused by the presence of a target
Sonar signal voltage	voltage at a sonar receiver, for a specified frequency band, caused by the sonar signal sound pressure
Target echo	sound at a sonar receiver originating from an active sonar transmission, and subsequently re-radiated by a target
Equivalent target strength	difference between sum of target echo level (LTE), propagation loss from sonar transmitter to target (NPL,Tx), and propagation loss from target to sonar receiver (NPL,Rx), and source level (LS)610).</description>
Auditory frequency weighting function	frequency weighting function chosen to represent a specified frequency-dependent characteristic of hearing sensitivity in a particular type of animal, by which an acoustic quantity is adjusted to reflect the importance of frequency dependence to that animal
Behavioural hearing threshold	minimum level of a specified sound signal that is capable of evoking a behaviourally measurable auditory sensation in a specified fraction of trials, for a specific subject and for specified conditions, including measurement geometry
Electrophysiological hearing threshold	minimum level of a specified signal that is capable of evoking a detectable and reproducible electrophysiological response, for a specific subject and for specified conditions, including measurement geometry
Hearing threshold shift	change in the behavioural hearing threshold or electrophysiological hearing threshold

5.11. MD_KeywordTypeCode

Element name	Element description
discipline	keyword identifies a branch of instruction or specialized learning
place	keyword identifies a location
dataResolution	keyword identifies a temporal or spatial resolution
stratum	keyword identifies the layer(s) of any deposited substance
temporal	keyword identifies a time period related to the dataset
theme	keyword identifies a particular subject or topic
dataCentre	keyword identifies a repository or archive that manages and distributes data
featureType	keyword identifies a resource containing or about a collection of feature instances with common characteristics
instrument	keyword identifies a device used to measure or compare physical properties
platform	keyword identifies a structure upon which an instrument is mounted
process	keyword identifies a series of actions or natural occurrences
project	keyword identifies an endeavour undertaken to create or modify a product or service
service	keyword identifies an activity carried out by one party for the benefit of another
product	keyword identifies a type of product
subTopicCategory	refinement of a topic category for the purpose of geographic data classification

5.12. DS_AssociationTypeCode

Element name	Element description
crossReference	reference from one dataset to another
largerWorkCitation	reference to a master dataset of which this one is a part
partOfSeamlessDatabase	part of the same structured set of data held in a computer
source	mapping and charting information from which the dataset content originates
stereoMate	part of a set of imagery that when used together, provides three-dimensional images
isComposedOf	reference to resources that are parts of this resource
collectiveTitle	common title for a collection of resources. NOTE: title identifies elements of a series collectively, combined with information about what volumes are available at the source cite
series	associated through a common heritage such as produced to a common product specification
dependency	associated through a dependency
revisionOf	resource is a revision of associated resource

5.13. CI_DateTypeCode

Element name	Element description
creation	date identifies when the resource was brought into existence
publication	date identifies when the resource was issued
revision	date identifies when the resource was examined or re-examined and improved or amended
expiry	date identifies when resource expires
lastUpdate	date identifies when resource was last updated
lastRevision	date identifies when resource was last reviewed
nextUpdate	date identifies when resource will be next updated
unavailable	date identifies when resource became not available or obtainable
inForce	date identifies when resource became in force
adopted	date identifies when resource was adopted
deprecated	date identifies when resource was deprecated
superseded	date identifies when resource was superseded or replaced by another resource
validityBegins	time at which the data are considered to become valid. NOTE: There could be quite a delay between creation and validity begins
validityExpires	time at which the data are no longer considered to be valid
released	the date that the resource shall be released for public access
distribution	date identifies when an instance of the resource was distributed

5.14. CI_RoleCode

Element name	Element description
resourceProvider	party that supplies the resource
custodian	party that accepts accountability and responsibility for the data and ensures appropriate care and maintenance of the resource
owner	party that owns the resource
sponsor	party that sponsors the resource
user	party who uses the resource
distributor	party who distributes the resource
originator	party who created the resource
pointOfContact	party who can be contacted for acquiring knowledge about or acquisition of the resource
principalInvestigator	key party responsible for gathering information and conducting research
processor	party who has processed the data in a manner such that the resource has been modified
publisher	party who published the resource
author	party who authored the resource
coAuthor	party who jointly authors the resource
collaborator	party who assists with the generation of the resource other than the principal investigator
editor	party who reviewed or modified the resource to improve the content
mediator	a class of entity that mediates access to the resource and for whom the resource is intended or useful
rightsHolder	party owning or managing rights over the resource
contributor	party contributing to the resource
funder	party providing monetary support for the resource
stakeholder	party who has an interest in the resource or the use of the resource

5.15. MD_RestrictionCode

Element name	Element description
copyright	exclusive right to the publication, production, or sale of the rights to a literary, dramatic, musical, or artistic work, or to the use of a commercial print or label, granted by law for a specified period of time to an author, composer, artist, distributor
patent	government has granted exclusive right to make, sell, use or license an invention or discovery
patentPending	produced or sold information awaiting a patent
trademark	a name, symbol, or other device identifying a product, officially registered and legally restricted to the use of the owner or manufacturer
license	formal permission to do something
intellectualPropertyRights	rights to financial benefit from and control of distribution of non-tangible property that is a result of creativity
restricted	withheld from general circulation or disclosure
otherRestrictions	limitation not listed
unrestricted	no constraints exist
licenceUnrestricted	formal permission not required to use the resource
licenceEndUser	formal permission required for a person or an entity to use the resource and that may differ from the person that orders or purchases it
licenceDistributor	formal permission required for a person or an entity to commercialize or distribute the resource
private	protects rights of individual or organizations from observation, intrusion, or attention of others
statutory	prescribed by law
confidential	not available to the public contains information that could be prejudicial to a commercial, industrial, or national interest
SBU	although unclassified, requires strict controls over its distribution.
in-confidence	with trust

5.16. MD_ClassificationCode

Element name	Element description
unclassified	available for general disclosure
restricted	not for general disclosure
confidential	available for someone who can be entrusted with information
secret	kept or meant to be kept private, unknown, or hidden from all but a select group of people
topSecret	of the highest secrecy
SBU	although unclassified, requires strict controls over its distribution
forOfficialUseOnly	unclassified information that is to be used only for official purposes determined by the designating body
protected	compromise of the information could cause damage
limitedDistribution	dissemination limited by designating body

5.17. MD_ScopeCode

Element name	Element description
attribute	information applies to the attribute class
attributeType	information applies to the characteristic of a feature
collectionHardware	information applies to the collection hardware class
collectionSession	information applies to the collection session
dataset	information applies to the dataset
series	information applies to the series
nonGeographicDataset	information applies to non-geographic data
dimensionGroup	information applies to a dimension group
feature	information applies to a feature
featureType	information applies to a feature type
propertyType	information applies to a property type
fieldSession	information applies to a field session
software	information applies to a computer program or routine
model	information applies to a copy or imitation of an existing or hypothetical object
tile	information applies to a tile, a spatial subset of geographic data
metadata	information applies to metadata
initiative	information applies to an initiative
sample	information applies to a sample
document	information applies to a document
aggregate	information applies to an aggregate resource
product	metadata describing an ISO 19131 data product specification
collection	information applies to an unstructured set
coverage	information applies to a coverage

5.18. MD_MaintenanceFrequencyCode

Element name	Element description
continual	data is repeatedly and frequently updated
daily	data is updated each day
weekly	data is updated on a weekly basis
fortnightly	data is updated every two weeks
monthly	data is updated each month
quarterly	data is updated every three months
biannually	data is updated twice each year
annually	data is updated every year
asNeeded	data is updated as deemed necessary
irregular	data is updated in intervals that are uneven in duration
notPlanned	there are no plans to update the data
unknown	frequency of maintenance for the data is not known

5.19. OOI Instrument types

Element name	Element description
Air-sea interface pCO2 sensor	Located at the sea surface, an Air-Sea Interface pCO2 Sensor measures the partial pressure of carbon dioxide (pCO2) in both the atmosphere and ocean. These measurements are used to calculate the exchange of CO2 between the air and sea (Air-Sea CO2 Flux).
Benthic fluid flow rate sampler	A Benthic Fluid Flow Rate Sampler measures the speed at which fluids seep from Earth’s crust into the surrounding ocean (Benthic Fluid Flow Rate).
Bio-acoustic sonar	Bio-acoustic Sonar measures fish and zooplankton concentrations using Acoustics. This instrument emits sound waves into the water column, which bounce off organisms back towards the sensor in a phenomenon known as ‘backscatter’. The more organisms, the higher the backscatter.
CTD	A CTD is so named as it measures Conductivity, Temperature and Depth. These parameters can then be used to calculate Salinity and Density.
Digital camera	Digital Cameras capture high-resolution photos (Still Images) of the seafloor environment that can be used for analytical work.
Dissolved oxygen sensor	A Dissolved Oxygen Sensor measures the concentration of oxygen molecules that have been dissolved, or mixed, into seawater (Dissolved Oxygen Concentration).
DNA sampler	A DNA Sampler filters a volume of seawater and preserves the particulate matter for genetic analysis after the instrument is recovered.
Fluorometer	A Fluorometer is a device used to measure patterns of Fluorescence. These data are used to determine Chlorophyll, Dissolved Organic Matter, and Turbidity.
HD video camera	HD Video Cameras capture High Definition (HD) Video of the seafloor environment that can be used for analytical work.
Hydrophone	A Hydrophone is a passive acoustic sensor that listens for earthquakes, sea creatures, and human-generated noise in the ocean.
Hydrothermal vent fluid chemistry sensor	Hydrothermal Vent Fluid Chemistry Sensors measure the chemical composition of the mineral-rich fluid plumes that emanate from cracks on the seafloor, providing insight into the sub-surface structure and dynamics of these unique habitats.
Hydrothermal vent fluid sampler	A Hydrothermal Vent Fluid Sampler collects a water sample and takes its temperature at the time of collection. Once recovered, laboratory tests are used to examine the chemistry of the vent fluid samples.
Hydrothermal vent fluid temperature sensor	Hydrothermal Vent Fluid Temperature Sensors measure the Water Temperature of the mineral-rich fluid plumes that emanate from cracks on the seafloor, providing insight into the sub-surface structure and dynamics of these unique habitats.
Light meter	A Light Meter is used to measure Downwelling Irradiance, the amount of light at a particular depth in the water column.
Mass spectrometer	A Mass Spectrometer measures the masses and relative concentrations of atoms and molecules in a water sample.
Nitrate sensor	Nitrate Sensors measure the amount of nitrate (NO3-) dissolved in seawater.
pH sensor	pH Sensors measure the concentration of hydrogen ions in a solution. Seawater has an average pH of 8.2, which is currently decreasing due to increases in carbon dioxide, a phenomenon known as Ocean Acidification.
Phtosynthetically active radiation sensor	A Photosynthetically Active Radiation (PAR) Sensor is used to measure the spectral range of light that is available for use by primary producers for photosynthesis (400-700 nanometers).
Seafloor pressure and tilt sensor	Seafloor Pressure and Tilt Sensors measure the force on the seafloor exerted by the weight of the overlying water and atmosphere (pressure) and movement of the seafloor itself (tilt). These measurements are used to understand changes in water depth (tides, waves) and the structure and dynamics of Oceanic Tectonic Plates.
Seafloor pressure sensor	A Seafloor Pressure Sensor measures the force on the seafloor exerted by the weight of the overlying water and atmosphere.
Sea-surface vertical eddy flux sensor	A Sea-Surface Vertical Eddy Flux Sensor measures a suite of parameters that describe the exchange of heat, moisture, and momentum between the ocean and the atmosphere. Sea-Surface Vertical Eddy Flux Sensors measure Air Temperature, Air-Sea Heat Flux, Wind Velocity, and Humidity.
Seawater pCO2 sensor	Seawater pCO2 Sensors measure the partial pressure of CO2 in seawater. Carbon enters the ocean mainly through the dissolution of atmospheric CO2 and undergoes a complex series of biological and chemical reactions.
Seismometer	Seismometers measure Seafloor Movement. These measurements provide insight into Seismic Activity and help to understand Volcanic Tremors, Seismology (including Earthquakes), and dynamics of Oceanic Tectonic Plates.
Surface wave sensor	A Surface Wave Sensor measures the frequency, height, period, and direction of waves on the ocean surface (Wave Properties). These sensors help to understand Turbulent Mixing in the surface ocean.
Turbidity meter	A Turbidity Meter measures suspended solids in seawater; i.e. cloudiness caused by particles in the water.
Velocity profiler - horizontal	The Velocity Profiler-Horizontal is an array of echo sounders on the seafloor. They send ‘pings’ (i.e., sound waves) to the sea surface and measure the length of time it takes the pings to return. These measurements are used to calculate the average horizontal movement of water within a column.
Velocity profiler - vertical	A Velocity Profiler - Vertical uses Acoustics to measure Water Velocity. Sound waves emitted by the profiler scatter off suspended particles and back to the sensor. The sensor calculates velocity by measuring changes in these sound waves (i.e., Doppler shifts).
Water velocity meter	A Water Velocity Meter measures the speed and direction of water as it moves past a single point.

5.20. MER:MI_EventTypeCode

Element name	Element description
announcement	Event which precedes other forthcoming events
calibration	Event which indicates when the instrument’s readings were aligned to match with physical reality
calibrationCoefficientUpdate	Event which indicates an update in calibration (as opposed to a whole new calibration)
dataLoss	Event either which caused data loss or was caused by data loss
fatal	Event which renders the instrument unusable
manoeuvre	Event tied to movements of the instrument
missingData	Event which either caused data to go missing or was caused by missing data
notice	General event which describes other closely related events
preLaunch	Event related to the pre-launch period
severe	Event which had a significant impact on the performance of the instrument
switchOff	Event which switched off or intentionally disabled the instrument
switchOn	Event which switched on or intentionally enabled the instrument

5.21. MI_OperationTypeCode

Element name	Element description
real	originates from live-fly or other non-simulated operational source
simulated	originates from target simulator sources
synthesized	mix of real and simulated data

5.22. MI_TriggerCode

Element name	Element description
automatic	event due to external stimuli
manual	event manually instigated
preProgrammed	event instigated by planned internal stimuli

5.23. MI_ContextCode

Element name	Element description
acquisition	event related to a specific domain
pass	event related to a sequence of collections
wayPoint	event related to navigational manoeuvre

5.24. MI_SequenceCode

Element name	Element description
start	beginning of a collection
end	end of a collection
instantaneous	collection without a significant duration

5.25. dwc:BasisOfRecordList

Element name	Element description
HumanObservation	An output of a human observation process.
MachineObservation	An output of a machine observation process.

5.26. Common data licenses

Element name	Element description
CC-BY (4.0)	Creative Commons - Attribution. This license lets others distribute, remix, tweak, and build upon your work, even commercially, as long as they credit you for the original creation. This is the most accommodating of licenses offered. Recommended for maximum dissemination and use of licensed materials.
CC-BY-SA (4.0)	Creative Commons - Attribution - Share Alike. This license lets others remix, tweak, and build upon your work even for commercial purposes, as long as they credit you and license their new creations under the identical terms. This license is often compared to “copyleft” free and open source software licenses. All new works based on yours will carry the same license, so any derivatives will also allow commercial use. This is the license used by Wikipedia, and is recommended for materials that would benefit from incorporating content from Wikipedia and similarly licensed projects.
CC-BY-ND (4.0)	Creative Commons - Attribution - No derivatives. This license lets others reuse the work for any purpose, including commercially; however, it cannot be shared with others in adapted form, and credit must be provided to you.
CC-BY-NC (4.0)	Creative Commons - Attribution - Non-commercial. This license lets others remix, tweak, and build upon your work non-commercially, and although their new works must also acknowledge you and be non-commercial, they don’t have to license their derivative works on the same terms.
CC-BY-NC-SA (4.0)	Creative Commons - Attribution - Non-commercial - Share Alike. This license lets others remix, tweak, and build upon your work non-commercially, as long as they credit you and license their new creations under the identical terms.
CC-BY-NC-ND (4.0)	Creative Commons - Attribution - Non-commercial - No derivatives. This license is the most restrictive of our six main licenses, only allowing others to download your works and share them with others as long as they credit you, but they can’t change them in any way or use them commercially.
CC0 (4.0)	Creative Commons - Public Domain. If you are the creator and owner of the copyright-protected work, choosing this option indicates you have waived all copyright protection and opted out of any exclusive rights granted to creators. You may only apply CC0 to your own work. You may retain certain moral (not legal) rights through the use of CC0.
PDDL (1.0)	Open Data Commons Public Domain Dedication and License. The PDDL places the data(base) in the public domain (waiving all rights). Similar to CC0.
ODC-By (1.0)	Open Data Commons Attribution License. Allows others to share, create, or adapt upon the data(base), providing they attribute any public use of the data(base) or works produced from the data(base) as specified in the license. Similar to CC-By.
ODC-ODbL (1.0)	Open Data Commons Open Database License. Allows others to share, create, or adapt upon the data(base), providing they attribute any public use of the data(base) or works produced from the data(base) as specified in the license, they share any adapted versions of the data(base) under the same license, and must offer an open version of the data(base) if they opt to redistribute the original or distribute their adaptation. Similar to CC-BY-SA.
OTHER	Any license not described here. Provide details on the license (e.g., full text or a link to access full text) in the field below.

5.27. Common software licenses

Element name	Element description
GNU General Public License 3.0	A copyleft license for software. Allows users substantial freedom of use and re-use, provided that changes are tracked and identified, and modifications of GPL 3 code (including software packaging) must be released under the same license. Equivalent access must be provided to compiled binaries and source. Note that users obtain the same rights as you - so are therefore allowed to redistribute software under their own terms. Further details available at gnu.org/licenses/gpl-3.0.html
GNU General Public License 2.0	A copyleft license for software. Similar to GNU GPL 3.0, but lacks direct compatibility with the Apache 2.0 license, lacks some protection against patent issues, and does not enforce the right to user control. Further details available at gnu.org/licenses/old-licenses/gpl-2.0.html
GNU Lesser General Public License 3.0	A version of the GNU GPL 3.0 which permits use of the software in entirely proprietary programs - and thus is not strictly copyleft. Further details are available at gnu.org/licenses/lgpl-3.0.html
X11 License	Sometimes called the MIT License. A lax permissive non-copyleft license for software. Essentially allows free unrestricted use so long as the original copyright and license statements are included. The X11 license is a slightly expanded version of the traditional “MIT” license which adds a restriction preventing using the license holders’ names for advertising without permission. Further details available at spdx.org/licenses/X11.html
Mozilla Public License 2.0	A copyleft software license which allows combining MPL 2.0 and proprietary software, so long as MPL 2.0 software is kept separate. Compatible with GPL 2.0 and newer. Further details available at mozilla.org/en-US/MPL/2.0/
Common Development and Distribution License	A software license which requires source code files under CDDL to remain under CDDL. While the license allows combining software from multiple licenses, it is not compatible with GPL. Further details are available at opensource.org/licenses/CDDL-1.0
Eclipse Public License 2.0	A software license with weak copyleft, allowing users to use, modify, copy, or distribute the work or modifications to it under the same license. Source code must be made available. Additions and changes which are not derivative may be re-licensed. Users also gain a license to any patents held by the creators covering modifications. It is not strictly compatible with the GNU GPL, but allows a secondary license designation which can incorporate mismatched licenses. For further details refer to eclipse.org/legal/epl-2.0/faq.php
Modified BSD License	Also known as the 3-clause BSD License. Allows almost unlimited freedom so long as the BSD copyright and license notice are included. Not to be confused with the original 4-clause BSD license. The 3-clause BSD removes the clause regarding advertising materials. For further details refer to opensource.org/licenses/BSD-3-Clause
FreeBSD License	Also known as the 2-clause BSD License. Allows almost unlimited freedom so long as the BSD copyright and license notice are included. Not to be confused with the original 4-clause BSD license or the modified (3-clause) BSD license. The 3-clause BSD removes the clause regarding advertising materials, and the 2-clause BSD further removes a clause regarding endorsements. For further details refer to opensource.org/licenses/BSD-2-Clause
Apache License 2.0	A permissive non-copyleft license. The same license must be applied to all unmodified parts and any original copyright, patent, trademark, etc… notices must be preserved, and any changes noted. Not compatible with GNU GPL 2.0. For more details refer to apache.org/licenses/LICENSE-2.0.html
CC0 (4.0)	Creative Commons - Public Domain. If you are the creator and owner of the copyright-protected work, choosing this option indicates you have waived all copyright protection and opted out of any exclusive rights granted to creators. You may only apply CC0 to your own work. You may retain certain moral (not legal) rights through the use of CC0.
OTHER	Any license not described here. Provide details on the license (e.g., full text or a link to access full text) in the field below.