SIST EN ISO 19111:2020

SLOVENSKI STANDARD
01-junij-2020
Nadomešča:
SIST EN ISO 19111:2008
SIST EN ISO 19111-2:2012
Geografske informacije - Lociranje s koordinatami (ISO 19111:2019)
Geographic information - Referencing by coordinates (ISO 19111:2019)
Information géographique - Système de références par coordonnées (ISO 19111:2019)
Ta slovenski standard je istoveten z: EN ISO 19111:2020
ICS:
07.040 Astronomija. Geodezija. Astronomy. Geodesy.
Geografija Geography
35.240.70 Uporabniške rešitve IT v IT applications in science
znanosti
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 19111
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2020
EUROPÄISCHE NORM
ICS 35.240.70
English Version
Geographic information - Referencing by coordinates (ISO
19111:2019)
Information géographique - Système de références par
coordonnées (ISO 19111:2019)
This European Standard was approved by CEN on 7 March 2020.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19111:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
The text of ISO 19111:2019 has been prepared by Technical Committee ISO/TC 211 "Geographic
information/Geomatics” of the International Organization for Standardization (ISO) and has been taken
over as EN ISO 19111:2020 by Technical Committee CEN/TC 287 “Geographic Information” the
secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by September 2020, and conflicting national standards
shall be withdrawn at the latest by September 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 19111:2019 has been approved by CEN as EN ISO 19111:2020 without any modification.

INTERNATIONAL ISO
STANDARD 19111
Third edition
2019-01
Geographic information —
Referencing by coordinates
Information géographique — Système de références par coordonnées
Reference number
ISO 19111:2019(E)
©
ISO 2019
ISO 19111:2019(E)
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
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Fax: +41 22 749 09 47
Email: copyright@iso.org
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Published in Switzerland
ii © ISO 2019 – All rights reserved

ISO 19111:2019(E)
Contents Page
Foreword .v
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 2
3.1 Terms and definitions . 2
3.2 Symbols .11
3.3 Abbreviated terms .11
4 Conformance requirements .12
5 Conventions .13
5.1 Unified Modeling Language notation .13
5.2 Attribute status .13
6 Referencing by coordinates — Data model overview .14
7 Coordinates package .15
7.1 Relationship between coordinates and coordinate reference system .15
7.2 Coordinate reference system identification .16
7.3 Requirements for coordinate metadata .16
7.3.1 Requirements class: Static CRS coordinate metadata .16
7.3.2 Requirements class: Dynamic CRS coordinate metadata .17
7.4 UML schema for the Coordinates package .17
7.5 UML schema for change of coordinates .19
8 Common Classes package .21
8.1 General attributes .21
8.1.1 Introduction .21
8.1.2 Name and alias.21
8.1.3 Identifier .21
8.1.4 Scope and Domain of Validity .21
8.2 UML schema for the Common Classes package .22
9 Coordinate Reference Systems package .25
9.1 Coordinate reference system .25
9.1.1 General.25
9.1.2 Principal subtypes of coordinate reference system .25
9.2 Derived coordinate reference system .26
9.2.1 General.26
9.2.2 Projected coordinate reference system .26
9.3 Compound coordinate reference system .27
9.3.1 General.27
9.3.2 Spatial compound coordinate reference system .27
9.3.3 Spatio-temporal compound coordinate reference system .27
9.3.4 Spatio-parametric compound coordinate reference system .27
9.3.5 Spatio-parametric-temporal compound coordinate reference system .27
9.4 UML schema for the Coordinate Reference Systems package .27
10 Coordinate Systems package .36
10.1 Coordinate system — General .36
10.2 Parametric coordinate system .37
10.3 Temporal coordinate system.37
10.4 Coordinate system axis .38
10.5 UML schema for the Coordinate Systems package.38
11 Datums (reference frames) package .49
11.1 Types of datum and reference frame .49
ISO 19111:2019(E)
11.2 Geodetic reference frame .49
11.2.1 Prime meridian .49
11.2.2 Ellipsoid .49
11.3 Dynamic reference frame .50
11.4 Datum ensemble .50
11.5 Temporal datum .50
11.6 UML schema for the Datums package .50
12 Coordinate Operations package .58
12.1 General characteristics of coordinate operations .58
12.2 UML schema for the Coordinate Operations package .59
Annex A (normative) Abstract test suite .71
Annex B (informative) Spatial referencing by coordinates — Geodetic concepts .76
Annex C (informative) Spatial referencing by coordinates — Context for modelling.81
Annex D (informative) Temporal referencing by coordinates — Context for modelling .95
Annex E (informative) Examples.99
Annex F (informative) Recommended best practice for interfacing to ISO 19111 .137
Annex G (informative) Backward compatibility with ISO 19111:2007 .138
Bibliography .143
iv © ISO 2019 – All rights reserved

ISO 19111:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics,
in close collaboration with the Open Geospatial Consortium (OGC).
This third edition cancels and replaces the second edition (ISO 19111:2007), which has been technically
revised. This document also incorporates the provisions of ISO 19111-2:2009, which is cancelled.
The changes in this edition compared to the previous edition are:
— inclusion of applicable modern geodetic terminology;
— extension to describe dynamic geodetic reference frames;
— extension to describe geoid-based vertical coordinate reference systems;
— extension to allow triaxial ellipsoid for planetary applications;
— extension to describe three-dimensional projected coordinate reference systems;
— addition of 'datum ensembles' to allow grouping of related realizations of a reference frame where
for lower accuracy applications the differences are insignificant;
— clarification in the modelling of derived coordinate reference systems;
— remodelling of the metadata elements scope and extent;
— addition of requirements to describe coordinate metadata and the relationship between spatial
coordinates;
— additional modelling of temporal coordinate reference system components sufficient for spatio-
temporal coordinate referencing;
— consolidation of the provisions of ISO 19111-2:2009 (Spatial referencing by coordinates — Extension
for parametric values) into this document;
ISO 19111:2019(E)
— change in name from 'Spatial referencing by coordinates' to 'Referencing by coordinates', due to the
inclusion of the non-spatial coordinate reference system subtypes of parametric (from ISO 19111-2)
and temporal;
— the correction of minor errors.
Further details are given in Annex G.
In accordance with the ISO/IEC Directives, Part 2, 2018, Rules for the structure and drafting of
International Standards, in International Standards the decimal sign is a comma on the line. However the
General Conference on Weights and Measures (Conférence Générale des Poids et Mesures) at its meeting
in 2003 passed unanimously the following resolution:
“The decimal marker shall be either a point on the line or a comma on the line.”
In practice, the choice between these alternatives depends on customary use in the language concerned.
In the technical areas of geodesy and geographic information it is customary for the decimal point
always to be used, for all languages. That practice is used throughout this document.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
vi © ISO 2019 – All rights reserved

ISO 19111:2019(E)
Introduction
Geographic information is inherently four-dimensional and includes time. The spatial component
relates the features represented in geographic data to positions in the real world. Spatial references fall
into two categories:
— those using coordinates;
— those based on geographic identifiers.
[5]
Spatial referencing by geographic identifiers is defined in ISO 19112 . This document describes the
data elements, relationships and associated metadata required for spatial referencing by coordinates,
expanded from a strictly spatial context to include time. The temporal element is restricted to temporal
coordinate systems having a continuous axis. The temporal element excludes calendars and ordinal
reference systems due to their complexities in definition and in transformation. The context is shown
in Figure 1.
Figure 1 — Context of referencing by coordinates
Certain scientific communities use three-dimensional systems where horizontal position is combined
with a non-spatial parameter. In these communities, the parameter is considered to be a third, vertical,
axis. The parameter, although varying monotonically with height or depth, does not necessarily vary in
a simple manner. Thus conversion from the parameter to height or depth is non-trivial. The parameters
concerned are normally absolute measurements and the datum is taken with reference to a direct
physical measurement of the parameter. These non-spatial parameters and parametric coordinate
reference system modelling constructs were previously described in ISO 19111-2:2009 but have been
incorporated into this revision because the modelling constructs are identical to the other coordinate
reference system types included in this document.
This document describes the elements that are necessary to fully define various types of coordinate
reference systems applicable to geographic information. The subset of elements required is partially
dependent upon the type of coordinates. This document also includes optional fields to allow for the
ISO 19111:2019(E)
inclusion of metadata about the coordinate reference systems. The elements are intended to be both
machine and human readable.
In addition to describing a coordinate reference system, this document provides for the description of
a coordinate operation between two different coordinate reference systems or a coordinate operation
to account for crustal motion over time. With such information, spatial data referenced to different
coordinate reference systems can be referenced to one specified coordinate reference system at one
specified time. This facilitates spatial data integration. Alternatively, an audit trail of coordinate
manipulations can be maintained.
viii © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 19111:2019(E)
Geographic information — Referencing by coordinates
1 Scope
This document defines the conceptual schema for the description of referencing by coordinates. It
describes the minimum data required to define coordinate reference systems. This document supports
the definition of:
— spatial coordinate reference systems where coordinate values do not change with time. The
system may:
— be geodetic and apply on a national or regional basis, or
— apply locally such as for a building or construction site, or
— apply locally to an image or image sensor;
— be referenced to a moving platform such as a car, a ship, an aircraft or a spacecraft. Such a
coordinate reference system can be related to a second coordinate reference system which is
referenced to the Earth through a transformation that includes a time element;
— spatial coordinate reference systems in which coordinate values of points on or near the surface of
the earth change with time due to tectonic plate motion or other crustal deformation. Such dynamic
systems include time evolution, however they remain spatial in nature;
— parametric coordinate reference systems which use a non-spatial parameter that varies
monotonically with height or depth;
— temporal coordinate reference systems which use dateTime, temporal count or temporal measure
quantities that vary monotonically with time;
— mixed spatial, parametric or temporal coordinate reference systems.
The definition of a coordinate reference system does not change with time, although in some cases some
of the defining parameters can include a rate of change of the parameter. The coordinate values within
a dynamic and in a temporal coordinate reference system can change with time.
This document also describes the conceptual schema for defining the information required to describe
operations that change coordinate values.
In addition to the minimum data required for the definition of the coordinate reference system or
coordinate operation, the conceptual schema allows additional descriptive information - coordinate
reference system metadata - to be provided.
This document is applicable to producers and users of geographic information. Although it is applicable
to digital geographic data, the principles described in this document can be extended to many other
forms of spatial data such as maps, charts and text documents.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 8601, Data elements and interchange formats — Information interchange — Representation of dates
and times
ISO 19111:2019(E)
ISO 19103, Geographic information — Conceptual schema language
ISO 19115-1:2014, Geographic information — Metadata — Part 1: Fundamentals
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at https: //www .iso .org/obp
3.1.1
affine coordinate system
coordinate system in Euclidean space with straight axes that are not necessarily mutually perpendicular
3.1.2
Cartesian coordinate system
coordinate system in Euclidean space which gives the position of points relative to n mutually
perpendicular straight axes all having the same unit of measure
Note 1 to entry: n is 2 or 3 for the purposes of this document.
Note 2 to entry: A Cartesian coordinate system is a specialisation of an affine coordinate system.
3.1.3
compound coordinate reference system
coordinate reference system using at least two independent coordinate reference systems
Note 1 to entry: Coordinate reference systems are independent of each other if coordinate values in one cannot
be converted or transformed into coordinate values in the other.
3.1.4
concatenated operation
coordinate operation consisting of the sequential application of multiple coordinate operations
3.1.5
coordinate
one of a sequence of numbers designating the position of a point
Note 1 to entry: In a spatial coordinate reference system, the coordinate numbers are qualified by units.
3.1.6
coordinate conversion
coordinate operation that changes coordinates in a source coordinate reference system to coordinates
in a target coordinate reference system in which both coordinate reference systems are based on the
same datum
Note 1 to entry: A coordinate conversion uses parameters which have specified values.
EXAMPLE 1 A mapping of ellipsoidal coordinates to Cartesian coordinates using a map projection.
EXAMPLE 2 Change of units such as from radians to degrees or from feet to metres.
3.1.7
coordinate epoch
epoch to which coordinates in a dynamic coordinate reference system are referenced
2 © ISO 2019 – All rights reserved

ISO 19111:2019(E)
3.1.8
coordinate operation
process using a mathematical model, based on a one-to-one relationship, that changes coordinates in
a source coordinate reference system to coordinates in a target coordinate reference system, or that
changes coordinates at a source coordinate epoch to coordinates at a target coordinate epoch within
the same coordinate reference system
3.1.9
coordinate reference system
coordinate system that is related to an object by a datum
Note 1 to entry: Geodetic and vertical datums are referred to as reference frames.
Note 2 to entry: For geodetic and vertical reference frames, the object will be the Earth. In planetary applications,
geodetic and vertical reference frames may be applied to other celestial bodies.
3.1.10
coordinate set
collection of coordinate tuples referenced to the same coordinate reference system and if that
coordinate reference system is dynamic also to the same coordinate epoch
3.1.11
coordinate system
set of mathematical rules for specifying how coordinates are to be assigned to points
3.1.12
coordinate transformation
coordinate operation that changes coordinates in a source coordinate reference system to coordinates
in a target coordinate reference system in which the source and target coordinate reference systems
are based on different datums
Note 1 to entry: A coordinate transformation uses parameters which are derived empirically. Any error in those
coordinates will be embedded in the coordinate transformation and when the coordinate transformation is
applied the embedded errors are transmitted to output coordinates.
Note 2 to entry: A coordinate transformation is colloquially sometimes referred to as a 'datum transformation'.
This is erroneous. A coordinate transformation changes coordinate values. It does not change the definition
of the datum. In this document coordinates are referenced to a coordinate reference system. A coordinate
transformation operates between two coordinate reference systems, not between two datums.
3.1.13
coordinate tuple
tuple composed of coordinates
Note 1 to entry: The number of coordinates in the coordinate tuple equals the dimension of the coordinate system;
the order of coordinates in the coordinate tuple is identical to the order of the axes of the coordinate system.
3.1.14
cylindrical coordinate system
three-dimensional coordinate system in Euclidean space in which position is specified by two linear
coordinates and one angular coordinate
3.1.15
datum
reference frame
parameter or set of parameters that realize the position of the origin, the scale, and the orientation of a
coordinate system
ISO 19111:2019(E)
3.1.16
datum ensemble
group of multiple realizations of the same terrestrial or vertical reference system that, for approximate
spatial referencing purposes, are not significantly different
Note 1 to entry: Datasets referenced to the different realizations within a datum ensemble may be merged
without coordinate transformation.
Note 2 to entry: ‘Approximate’ is for users to define and typically is in the order of under 1 decimetre but may be
up to 2 metres.
EXAMPLE “WGS 84” as an undifferentiated group of realizations including WGS 84 (TRANSIT), WGS 84
(G730), WGS 84 (G873), WGS 84 (G1150), WGS 84 (G1674) and WGS 84 (G1762). At the surface of the Earth these
have changed on average by 0.7 m between the TRANSIT and G730 realizations, a further 0.2 m between G730 and
G873, 0.06 m between G873 and G1150, 0.2 m between G1150 and G1674 and 0.02 m between G1674 and G1762).
3.1.17
depth
distance of a point from a chosen vertical reference surface downward along a line that is perpendicular
to that surface
Note 1 to entry: The line direction may be straight, or be dependent on the Earth's gravity field or other physical
phenomena.
Note 2 to entry: A depth above the vertical reference surface will have a negative value.
3.1.18
derived coordinate reference system
coordinate reference system that is defined through the application of a specified coordinate conversion
to the coordinates within a previously established coordinate reference system
Note 1 to entry: The previously established coordinate reference system is referred to as the base coordinate
reference system.
Note 2 to entry: A derived coordinate reference system inherits its datum or reference frame from its base
coordinate reference system.
Note 3 to entry: The coordinate conversion between the base and derived coordinate reference system is
implemented using the parameters and formula(s) specified in the definition of the coordinate conversion.
3.1.19
dynamic coordinate reference system
coordinate reference system that has a dynamic reference frame
Note 1 to entry: Coordinates of points on or near the crust of the Earth that are referenced to a dynamic
coordinate reference system may change with time, usually due to crustal deformations such as tectonic motion
and glacial isostatic adjustment.
Note 2 to entry: Metadata for a dataset referenced to a dynamic coordinate reference system should include
coordinate epoch information.
3.1.20
dynamic reference frame
dynamic datum
reference frame in which the defining parameters include time evolution
Note 1 to entry: The defining parameters that have time evolution are usually a coordinate set.
3.1.21
easting
E
distance in a coordinate system, eastwards (positive) or westwards (negative) from a north-south
reference line
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ISO 19111:2019(E)
3.1.22
ellipsoid
reference ellipsoid
geometric reference surface embedded in 3D Euclidean space formed by an ellipse that is
rotated about a main axis
Note 1 to entry: For the Earth the ellipsoid is bi-axial with rotation about the polar axis. This results in an oblate
ellipsoid with the midpoint of the foci located at the nominal centre of the Earth.
3.1.23
ellipsoidal coordinate system
geodetic coordinate system
coordinate system in which position is specified by geodetic latitude, geodetic longitude and (in the
three-dimensional case) ellipsoidal height
3.1.24
ellipsoidal height
geodetic height
h
distance of a point from the reference ellipsoid along the perpendicular from the reference ellipsoid to
this point, positive if upwards or outside of the reference ellipsoid
Note 1 to entry: Only used as part of a three-dimensional ellipsoidal coordinate system or as part of a three-
dimensional Cartesian coordinate system in a three-dimensional projected coordinate reference system, but
never on its own.
3.1.25
engineering coordinate reference system
coordinate reference system based on an engineering datum
EXAMPLE 1 System for identifying relative positions within a few kilometres of the reference point, such as a
building or construction site.
EXAMPLE 2 Coordinate reference system local to a moving object such as a ship or an orbiting spacecraft.
EXAMPLE 3 Internal coordinate reference system for an image. This has continuous axes. It may be the
foundation for a grid.
3.1.26
engineering datum
local datum
datum describing the relationship of a coordinate system to a local reference
Note 1 to entry: Engineering datum excludes both geodetic and vertical reference frames.
3.1.27
epoch
point in time
Note 1 to entry: In this document an epoch is expressed in the Gregorian calendar as a decimal year.
EXAMPLE 2017-03-25 in the Gregorian calendar is epoch 2017.23.
3.1.28
flattening
f
ratio of the difference between the semi-major axis (a) and semi-minor axis (b) of an ellipsoid to the
semi-major axis: f = (a – b)/a
Note 1 to entry: Sometimes inverse flattening 1/f = a/(a − b) is given instead; 1/f is also known as reciprocal
flattening.
ISO 19111:2019(E)
3.1.29
frame reference epoch
epoch of coordinates that define a dynamic reference frame
3.1.30
geocentric latitude
angle from the equatorial plane to the direction from the centre of an ellipsoid through a given point,
northwards treated as positive
3.1.31
geodetic coordinate reference system
three-dimensional coordinate reference system based on a geodetic reference frame and having either
a three-dimensional Cartesian or a spherical coordinate system
Note 1 to entry: In this document a coordinate reference system based on a geodetic reference frame and having
an ellipsoidal coordinate system is geographic.
3.1.32
geodetic latitude
ellipsoidal latitude
φ
angle from the equatorial plane to the perpendicular to the ellipsoid through a given point, northwards
treated as positive
3.1.33
geodetic longitude
ellipsoidal longitude
λ
angle from the prime meridian plane to the meridian plane of a given point, eastward treated as positive
3.1.34
geodetic reference frame
reference frame or datum describing the relationship of a two- or three-dimensional coordinate system
to the Earth
Note 1 to entry: In the data model described in this document, the UML class GeodeticReferenceFrame includes
both modern terrestrial reference frames and classical geodetic datums.
3.1.35
geographic coordinate reference system
coordinate reference system that has a geodetic reference frame and an ellipsoidal coordinate system
3.1.36
geoid
equipotential surface of the Earth’s gravity field which is perpendicular to the direction of gravity and
which best fits mean sea level either locally, regionally or globally
3.1.37
gravity-related height
H
height that is dependent on the Earth’s gravity field
Note 1 to entry: This refers to, amongst others, orthometric height and Normal height, which are both
approximations of the distance of a point above the mean sea level, but also may include Normal-orthometric
heights, dynamic heights or geopotential numbers.
Note 2 to entry: The distance from the reference surface may follow a curved line, not necessarily straight, as it is
influenced by the direction of gravity.
6 © ISO 2019 – All rights reserved

ISO 19111:2019(E)
3.1.38
height
distance of a point from a chosen reference surface positive upward along a line perpendicular to
that surface
Note 1 to entry: A height below the reference surface will have a negative value.
Note 2 to entry: Generalisation of ellipsoidal height (h) and gravity-related height (H).
3.1.39
linear coordinate system
one-dimensional coordinate system in which a linear feature forms the axis
EXAMPLE 1 Distances along a pipeline.
EXAMPLE 2 Depths down a deviated oil well bore.
3.1.40
map projection
coordinate conversion from an ellipsoidal coordinate system to a plane
3.1.41
mean sea level
MSL
average level of the surface of the sea over all stages of tide and seasonal variations
Note 1 to entry: Mean sea level in a local context normally means mean sea level for the region calculated from
observations at one or more points over a given period of time. To meet IHO standards that period should be one
full lunar cycle of 19 years. Mean sea level in a global context differs from a global geoid by not more than 2 m.
3.1.42
meridian
intersection of an ellipsoid by a plane containing the shortest axis of the ellipsoid
Note 1 to entry: This term is generally used to describe the pole-to-pole arc rather than the complete closed figure.
3.1.43
northing
N
distance in a coordinate system, northwards (positive) or southwards (negative) from an east-west
reference line
3.1.44
parameter reference epoch
epoch at which the parameter values of a time-dependent coordinate transformation are valid
Note 1 to entry: The transformation parameter values first need to be propagated to the epoch of the coordinates
before the coordinate transformation can be applied.
3.1.45
parametric coordinate reference system
coordinate reference system based on a parametric datum
3.1.46
parametric coordinate system
one-dimensional coordinate system where the axis units are parameter values which are not
inherently spatial
3.1.47
parametric datum
datum describing the relationship of a parametric coordinate system to an object
Note 1 to entry: The object is normally the Earth.
ISO 19111:2019(E)
3.1.48
point motion operation
coordinate operation that changes coordinates within one coordinate reference system due to the
motion of the point
Note 1 to entry: The change of coordinates is from those at an initial epoch to those at another epoch.
Note 2 to entry: In this document the point motion is due to tectonic motion or crustal deformation.
3.1.49
polar coordinate system
two-dimensional coordinate system in Euclidean space in which position is specified by one distance
coordinate and one angular coordinate
Note 1 to entry: For the three-dimensional case, see spherical coordinate system.
3.1.50
prime meridian
meridian from which the longitudes of other meridians are quantified
3.1.51
projected coordinate reference system
coordinate reference system derived from a geographic coordinate reference system by applying a map
projection
Note 1 to entry: May be two- or three-dimensional, the dimension being equal to that of the geographic coordinate
reference system from which it is derived.
Note 2 to entry: In the three-dimensional case the horizontal coordinates (geodetic latitude and geodetic
longitude coordinates) are projected to northing and easting and the ellipsoidal height is unchanged.
3.1.52
reference frame
datum
parameter or set of parameters that realize the position of the origin, the scale, and the orientation of a
coordinate system
3.1.53
semi-major axis
a
semi-diameter of the longest axis of an ellipsoid
3.1.54
semi-minor axis
b
semi-diameter of the shortest ax
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