Coordinate Reference Systems
SAInt uses a topological model to describe any network. Only nodes and branches are relevant, not their position. The length of a pipeline or of an electric line is just another attribute of an object that a user provides and that it is used in a set of equations. However, there are cases where the geographic position and geometry of a network are important elements. For example, the user needs to relate a network to the spatial distribution of houses or roads. Or it is necessary to overlay two networks to assess the feasibility of coupling points better. Or simply to see a network on a geographic map or satellite image. When it comes to representing and managing networks with an explicit spatial dimension, SAInt uses a simple and user-friendly approach.
For those kinds of applications, SAInt uses a dedicated "geographic Map Window". A geographic Map Window is a special map window where coordinates use a geographic system (i.e., longitude and latitude in degrees) instead of a Cartesian system (i.e., x and y in a linear unit of measurement). SAInt´s "coordinate reference system" (CRS) is known as the "World Geodetic System 1984 projection" (in short WGS84), and it is commonly used by services like Google Maps, OpenStreetMap, and GPS systems. This projection is based on the WGS84 datum ensemble and uses an ellipsoidal coordinate system with axes for latitude and longitude, orientation north and east, and the unit of measurement degree. SAInt also restricts the range of accepted coordinates to a latitude between 85.0°S and 85.0°N and a longitude between 180.0°E and 180.0°W.
For a systematic introduction to maps and coordinate systems, refer to the work of D. H. Maling (1992)[1].
1. Supported CRS
In cartography, a "coordinate reference system" (CRS) is defined as the combination of a "datum", a "projection", and a "coordinate system" to represent objects on the Earth on a map. A "datum" is a model of the Earth where we fix and mathematically describe a reference surface to provide known locations to begin surveys and create maps. A "coordinate system" is a set of mathematical rules defining how to represent and position an object in a reference space. A "projection" is a series of mathematical transformations that convert an initial coordinate system to a target coordinate system. By using an appropriate projection, the location of points on the curved surface of the selected Earth model is mapped to the corresponding location of a flat plane (i.e., a map) or space if elevation is considered.
SAInt supports the same set of coordinate reference systems available in the "European Petroleum Survey Group Geodetic Parameter Dataset" by the "International Association of Oil & Gas Producers" (IOGP). SAInt covers the most common CRS used at the international level for North and South America, Europe, and all the other continents, and it allows to convert data using established datum like:
-
"North American Datum" of 1983 (with epoch 2010;
NAD83, EPSG:4269); -
"North American Datum" of 1927 (
NAD27, EPSG:4267); -
"World Geodetic System" of 1984 (
WGS84, EPSG:4326); -
"European Terrestrial Reference System" of 1989 (
ETRS89, EPSG:4258).
SAInt supports projecting data to standard projections like the "Universal Transverse Mercator" or the "Pseudo-Mercator" (EPSG:3857), along with a variety of national projection systems (e.g., State Plane "New York Long Island" [EPSG:4456]).
Supported CRS are identified using an EPSG code. The code is based on the "European Petroleum Survey Group Geodetic Parameter Dataset", which is a collection of definitions of coordinate reference systems and coordinate transformations maintained by the Geodesy Subcommittee of the "IOGP Geomatics Committee". For details on the supported projections, please consult the website of the "EPSG Dataset".
Table 1 describes some of the supported coordinate reference systems. Entries are classified based on the geographic area, projection type, and datum. For Universal Transverse Mercator (UTM) projections, the zone number and main section (North or South) is reported.
-
World
-
National
-
Unites States and Canada
-
Europe
-
UTM North
-
UTM South
| Name | Datum | Zone | EPSG Code | Type |
|---|---|---|---|---|
World Geodetic System (WGS84) |
WGS84 |
- |
4326 |
Geographic |
Mercator projection |
WGS84 |
- |
3857 |
Projected |
| Name | Datum | Zone | EPSG Code | Type |
|---|---|---|---|---|
New York Long Island |
NAD27 |
4456 |
Projected |
|
New York East (ftUS) |
NAD83 |
2260 |
Projected |
|
Massachusetts Mainland |
NAD83 |
26986 |
Projected |
| Name | Datum | Zone | EPSG Code | Type |
|---|---|---|---|---|
Universal Transverse Mercator (UTM) |
NAD83 |
8N |
26908 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
9N |
26909 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
10N |
26910 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
11N |
26911 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
12N |
26912 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
13N |
26913 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
14N |
26914 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
15N |
26915 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
16N |
26916 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
17N |
26917 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
18N |
26918 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
19N |
26919 |
Projected |
Universal Transverse Mercator (UTM) |
NAD83 |
20N |
26920 |
Projected |
| Name | Datum | Zone | EPSG Code | Type |
|---|---|---|---|---|
Universal Transverse Mercator (UTM) |
ETRS89 |
28N |
25828 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
29N |
25829 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
30N |
25830 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
31N |
25831 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
32N |
25832 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
33N |
25833 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
34N |
25834 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
35N |
25835 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
36N |
25836 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
37N |
25837 |
Projected |
Universal Transverse Mercator (UTM) |
ETRS89 |
38N |
25838 |
Projected |
| Name | Datum | Zone | EPSG Code | Type |
|---|---|---|---|---|
Universal Transverse Mercator (UTM) |
WGS84 |
1N |
32601 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
2N |
32602 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
3N |
32603 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
4N |
32604 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
5N |
32605 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
6N |
32606 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
7N |
32607 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
8N |
32608 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
9N |
32609 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
10N |
32610 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
11N |
32611 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
12N |
32612 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
13N |
32613 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
14N |
32614 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
15N |
32615 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
16N |
32616 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
17N |
32617 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
18N |
32618 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
19N |
32619 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
20N |
32620 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
21N |
32621 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
22N |
32622 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
23N |
32623 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
24N |
32624 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
25N |
32625 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
26N |
32626 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
27N |
32627 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
28N |
32628 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
29N |
32629 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
30N |
32630 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
31N |
32631 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
32N |
32632 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
33N |
32633 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
34N |
32634 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
35N |
32635 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
36N |
32636 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
37N |
32637 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
38N |
32638 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
39N |
32639 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
40N |
32640 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
41N |
32641 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
42N |
32642 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
43N |
32643 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
44N |
32644 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
45N |
32645 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
46N |
32646 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
47N |
32647 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
48N |
32648 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
49N |
32649 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
50N |
32650 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
51N |
32651 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
52N |
32652 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
53N |
32653 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
54N |
32654 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
55N |
32655 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
56N |
32656 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
57N |
32657 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
58N |
32658 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
59N |
32659 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
60N |
32660 |
Projected |
| Name | Datum | Zone | EPSG Code | Type |
|---|---|---|---|---|
Universal Transverse Mercator (UTM) |
WGS84 |
1N |
32601 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
2N |
32602 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
3N |
32603 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
4N |
32604 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
5N |
32605 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
6N |
32606 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
7N |
32607 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
8N |
32608 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
9N |
32609 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
10N |
32610 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
11N |
32611 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
12N |
32612 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
13N |
32613 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
14N |
32614 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
15N |
32615 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
16N |
32616 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
17N |
32617 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
18N |
32618 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
19N |
32619 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
20N |
32620 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
21N |
32621 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
22N |
32622 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
23N |
32623 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
24N |
32624 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
25N |
32625 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
26N |
32626 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
27N |
32627 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
28N |
32628 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
29N |
32629 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
30N |
32630 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
31N |
32631 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
32N |
32632 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
33N |
32633 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
34N |
32634 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
35N |
32635 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
36N |
32636 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
37N |
32637 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
38N |
32638 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
39N |
32639 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
40N |
32640 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
41N |
32641 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
42N |
32642 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
43N |
32643 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
44N |
32644 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
45N |
32645 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
46N |
32646 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
47N |
32647 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
48N |
32648 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
49N |
32649 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
50N |
32650 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
51N |
32651 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
52N |
32652 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
53N |
32653 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
54N |
32654 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
55N |
32655 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
56N |
32656 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
57N |
32657 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
58N |
32658 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
59N |
32659 |
Projected |
Universal Transverse Mercator (UTM) |
WGS84 |
60N |
32660 |
Projected |
|
When writing the EPSG code for the CRS of choice in the column |
2. Coordinate conversion
A "coordinate conversion" is a set of mathematical rules to transform coordinates from one coordinate reference system to another. The conversion involves only the projection or the datum, or, in the most complicated situations, both. The difference in coordinates between datums is commonly referred to as "datum shift" and can vary from zero to hundreds of meters depending on the data and locations.
It is possible to have different types of data (e.g., geodetic or local), multiple types of coordinate systems (e.g., geographic or projected), and a variety of projections (for local use up to continental descriptions). Due to this variety of cases, the conversion procedure could be quite complex and may required in-depth knowledge of the different components involved.
SAInt performs datum "conversion" when exporting to a coordinate system with a datum different from WGS84. Examples of supported data are listed in Table 1. The applied transformation is the one with the smallest error for the specific target projection area.
SAInt uses the "Geospatial Data Abstraction Library" (GDAL) by the "Open Source Geospatial Foundation" to handle coordinate conversions. The user can select as source/target CRS any of the CRSs supported. See "Export to Network Import File" for an example of the export procedure.
|
Check the How-To "Import data with a Coordinate Reference System" for a step-by-step description of how to specify the CRS in your import template. |