1) The document discusses coordinate systems used in GIS, specifically geographic and projected coordinate systems. 2) The basic coordinate system used to represent locations on Earth is latitude and longitude, which form a geographic grid. 3) Projected coordinate systems like UTM transform latitude and longitude coordinates into plane coordinates for use in GIS.

1. 29 October, 2020 1
Lecture 10 & 11 - GIS
Coordinate Systems

2. Lecture # 10 & 11 Dated:29/10/2020
Course(502) Introduction to GIS and RS
Topic
Presented by
Rehana Jamal (Geometiciation, GIS Specialist & Geographer)
Visiting lecturer/GIS Trainer
studentsdatafiles@gmail.com
Faculty of Agricultural Engineering, Arid Agriculture University,
Rawalpindi
Coordinate Systems
used in GIS
29 October, 2020 2
Coordinate Systems

3. A coordinate system is a reference system used to represent the
locations of geographic features, imagery, and observations such
as GPS locations within a common geographic framework.
What is a Coordinate System?
29 October, 2020 3
Coordinate Systems

4. 29 October, 2020 4
Geographical grid
The geographic grid is a system designed to pinpoint any location on Earth by
laying a vertical and horizontal grid over the Earth's layout. The vertical lines
are called the longitude and the horizontal lines are the latitude. The
intersection of these two points determines any exact location on the grid that
can be seen on maps and globes, and defines the absolute location in a series of
numbered degrees that can be understood worldwide.
Coordinate Systems

5. 29 October, 2020
Coordinate Systems 5
Latitude and Longitude Coordinates

6. 29 October, 2020
Coordinate Systems 6

7. 29 October, 2020
Coordinate Systems 7

8. 29 October, 2020
8
Geographical grid
Coordinate Systems

9. Latitude is the angular distance of a
point away from the equator measured
from the center of the globe 90 degrees
North (0 to +90) or South (0 to -90) .
Latitude and Longitude Coordinates
In order to describe positions on a sphere we use the Latitude, Longitude coordinate
system.
Determination of Latitude:
Longitude is the angular distance of a point from the
Principal Meridian measured from the center of the
globe 180 degrees East (0 to +180) or West (0 to -180).
The Principal Meridian is also referred to as the Prime
Meridian or Greenwich Meridian.
Determination of Longitude:
9
29 October, 2020
Coordinate Systems

10. GRATICULE
A
B
 Network of parallels and meridians
 Main theme of map projection
 Indicates Position on globe
10
29 October, 2020
Coordinate Systems

11. 29 October, 2020
Coordinate Systems 11
GRATICULE

12. Parallels of Latitude
Area between two
successive parallels
ZONE
12
29 October, 2020
Coordinate Systems

13. GORE
Area between two
successive meridians
Meridians of Longitude
13
29 October, 2020
Coordinate Systems

14. Coordinate Systems
A basic principle of using
Coordinate systems in GIS
 To align the
map layers
spatially
together
29 October, 2020 14
Coordinate Systems

15. Coordinate Systems
 Locations of Map features are based on plane coordinate
system
 Locations of spatial features on the earth surface are based
on geographic coordinate system(Lat.& Long.)
Process of projection transformation from the
Earth surface to a Plane is called Map Projection.
29 October, 2020 15
Coordinate Systems

16. 29 October, 2020
Coordinate Systems 16
 A spatial reference describes where features are located in the real
world.
Coordinate Systems
X,y coordinates are georeferenced with a geographic or projected
coordinate system.
GIS Users typically work with plane coordinate system
Projection Transformation : Very Beginning Task
 Coordinate systems enable geographic datasets to use common
locations for integration.

17. 29 October, 2020
Coordinate Systems 17
2.Projected coordinate system
Types of coordinate systems
1.Geographic coordinate systems

18. 29 October, 2020
Coordinate Systems 18
Source:https://www.google.com/

19. 29 October, 2020
Coordinate Systems 19
Equator
 A geographic coordinate
system (GCS) is defined by a
datum, an angular unit of
measure (usually degrees), and
a prime meridian.
 A point is referenced by its
longitude and latitude values.
 Longitude and latitude are
angles measured from the
earth's center to a point on the
earth's surface.
1.Geographic Coordinate System (GCS)

20.  A projected coordinate system is defined on a flat, two-dimensional
surface.
 Unlike a Geographic Coordinate System (GCS, a projected
coordinate system has constant lengths, angles, and areas across the
two dimensions.
 A projected coordinate system is always based on a geographic
coordinate system that is based on a sphere or spheroid.
2.Projected coordinate system
29 October, 2020 20
Coordinate Systems

21. The ellipsoidal form of the Transverse Mercator projection was developed by Carl Friedrich
Gauss in 1825.It has become the most used because it allows precise measurements in meters
to within 1 meter.
It was further analyzed by Johann Heinrich Louis Krüger in 1912. The projection is
known by several names:
Gauss Conformal or Gauss-Krüger in Europe;
Transverse Mercator in the US; or Gauss-Krüger Transverse Mercator generally
The projection is conformal with a constant scale on the central meridian.
Universal Transverse Mercator (UTM)
The Universal Transverse Mercator coordinate system was developed by the United States
Army Corps of Engineers in the 1940s.The system was based on an ellipsoidal model of
Earth. For areas within the conterminous United States, the Clarke 1866 ellipsoid was used.
For the remaining areas of Earth, including Hawaii, the International Ellipsoid was used.
Currently, the WGS 84 ellipsoid is used as the underlying model of Earth in the UTM
coordinate system.
29 October, 2020 21
Coordinate Systems

22. Universal Transverse Mercator (UTM)
29 October, 2020 22
Coordinate Systems

23. Universal Transverse Mercator (UTM)
Universal North Polar(UNP)
Universal South Polar(USP)
29 October, 2020 23
Coordinate Systems

24. Universal Transverse Mercator (UTM)
False Origin of Southern Hemisphere = 10,000,000 meters
False Origin of Northern Hemisphere = 0 at equator
Maximum northing value = 9,328,000 meters at the 84˚parallel
29 October, 2020 24
Coordinate Systems

25. UTM grid
False Origin of Southern Hemisphere = 10,000,000 meters at the 80˚S
Maximum northing value = 9,328,000 meters at the 84˚N parallel
False Origin of Northern Hemisphere = 0 at equator
29 October, 2020 25
Coordinate Systems
False
Northing
False Easting
False
Origin
0

26. Location of Pakistan in UTM Zones Map Projection
Source: http://whatutmzoneamiin.blogspot.com/p/map.html 29 October, 2020 26
Coordinate Systems

27. 29 October, 2020
Coordinate Systems 27
False Northing
False Easting
False Origin of each zone
Location 4
False Northing = 3,900,000 m
False Easting = 500,000m

28. Source: http://whatutmzoneamiin.blogspot.com/p/map.html
Latitude
Band
Designator
(R)=1000,000
UTM Zone 41 N 60°-66°
63°
60° 66°
3,000,000 m Northing
0 Easting
Central
meridian
of
Zone
=500,000m
How to read a UTM Zone in Baluchistan
O
29 October, 2020 28
Coordinate Systems
4,000,000 m Northing
1000,000 Easting
1
2
3
4

29. 29 October, 2020 29
Coordinate Systems

30. 29 October, 2020
Coordinate Systems 30
Summary
The basic coordinates system to represent earth is based on latitude and
longitude in the form of a graticule.
Two coordinate systems i.e. geographic or projected(UTM) are used in GIS.
In GIS x,y coordinates are georeferenced with a geographic or projected
coordinate system.
A spatial reference describes where features are located in the real world.
Coordinate systems enable geographic datasets to use common locations for
integration.
Note: GIS Users typically work with plane coordinate system(UTM)

31. References:
 http://geology.isu.edu/geostac/Field_Exercise/topomaps/utm.htm for UTM Projection
 http://geokov.com/education/utm.aspx (Good description for UTM Projection)
 http://geology.isu.edu/geostac/Field_Exercise/topomaps/utm.htm
 http://geology.isu.edu/geostac/Field_Exercise/topomaps/utm.htm
 http://www.progonos.com/furuti/MapProj/Dither/ProjTbl/Img/tn-Sinusoidal.png
 http://earth.rice.edu/mtpe/geo/geosphere/topics/projections.jpg
 http://en.wikipedia.org/wiki/Map_projection
 http://vterrain.org/Projections/UTM.html (Consult this site for the notes)
 http://geography.about.com/library/weekly/aa031599.htm
 Practical Geography for B.A. B.Sc. by Mian Mohammad Anwar
29 October, 2020 31
Coordinate Systems