Universal Polar Stereographic Co-ordinate System

Sahibzada Uzair Ullah

What is UPS?UPS stands for Universal Polar Stereographic Co-ordinate System.

It is made to cover poles of the earth

It is basically a planar or azimuthal projection.

Bearing is much more accurate than shape or area.

Why UPS is needed?All the Maps of the earth now a days are

generally made on UTM(Universal Tranverse Mercator).

UTM is basically a secant cylindrical projection shown below.

Contnd….UTM is not discussed comprehensively

because it is out of scope of this presentation.The area we are concerned is

Why UTM can’t cover PolesS.F.(P)

1.00041.0

0.9996

1.0

1.0004

Why UTM can’t cover PolesThe spaced marked by highligther is not

covered in UTM because the S.F in this region become un-acceptable. (0.9996<S.F<1.0004)

So What About the POLES?

Here UPS comes for your rescue.

Universal Polar Stereographic Co-ordinate SystemUPS covers the Earth from 84○ to 90○ North

PoleIt covers the Earth 80○ to 90○ South pole.

To give a better Understanding lets have a look at the following picture…….

Method to Draw UPS ProjectionsAs already said it is an azimuthal or planar

projection so it is simply drawn by placing a plane surface on top of globe, as shown in fig.

Contd…..The final shape of this comes out to be

Contd…It covers North and south poles w.r.t bearing

and shape.The latitude in the projection are represented

as concentric circlesThe longitudes are represented by

concurrent lines passing through the centre.

Terminologies Of UPSFALSE Easting & false Northing: It

is hypothetical value of easting & northing assigned to the point of intersection of 0○-180○ and 90○ E – 90○ W (The Polar Origin).

The Values are 2,000,000 east and 2,000,000 north.

Characteristics Of UPSUPS is defined on WGS-84 ellipsoid.

The characteristics of WGS-84 are

Major axis=a=6378137 meters

Falttening=1/f=298.257223563

Contnd….UPS projection parameters are given by:Ø =geodetic latitudeX=isometric latitudeλ=longitudeZ= isometric colatitude=90 – isometric

latitudeK=scale factor for poles

Zones Of UPSThe alphabets left over from UTM such as

A ,B ,X, Y, Z are used for the zones of polar areas.

The Letter A is a grid zone designation for the area West to the meridian drawn from 0-180 degree.

Letter B is used fro the same extent of area to the east of meridian.

In the North polar area Y is grid zone designation for western area.

Contd…Z is used as grid designation for the

eastern area of North Pole from 0-180 degree.

The zone divided by UTM are further divided into squares of 100,000 to 10,000 and 1000 meters.

To have good idea Just have a look over the picture in the next slide.

Zones Of UPS