Israeli Transverse Mercator


Israeli Transverse Mercator is the new geographic coordinate system for Israel. The name is derived from the Transverse Mercator projection it uses and the fact that it is optimized for Israel. ITM has replaced the old coordinate system ICS. This coordinate system is sometimes also referred as the "New Israeli Grid". It has been use since January 1, 1994.

The need for a new grid

ITM replaced the old grid ICS which was based on the Cassini-Soldner projection. The central meridian in the new projection, as in the old one, crosses through Jerusalem. Replacing the projection eliminates two prominent drawbacks in the old network: assigning negative latitudinal values to the Southern Negev and the possibility of confusing coordinate values on the X and Y axes. The new system relocated the Y axis 50 km westward and the X axis 500 km southward so that now the entire country is covered by positive coordinate values.
Additional information on the creation of the new grid is available in Hebrew

Examples

An ITM coordinate is generally given as a pair of two six digit numbers. The first number is always the Easting and the second is the Northing. The easting and northing are in metres from the false origin.
The ITM coordinate for the Western Wall at Jerusalem is:
The first figure is the easting and means that the location is 222,286 meters east from the false origin. The second figure is the northing and puts the location 631,556 meters north of the false origin. Also notice how the easting in this example is indicated with an “E” and likewise an “N” for the northing. The fact that the coordinate is in meters is indicated by the lowercase m.
The table below shows the same coordinate in 3 different grids:
GridEastingNorthing
ITM 222286631556
ICS 1722491131586
UTM 7115633518045

Grid Parameters

The ITM coordinate system is defined by the following parameters:
Projection
Transverse Mercator
Reference ellipsoid
EllipsoidGRS80-
Semi-major axis a6378137.000meter
Inverse flattening 298.257222100882711-

Origin Point
False Origin
False Easting219529.584meter
False Northing626907.390meter
Scale Factor1.0000067-

Parameters for conversion to WGS84

Reference ellipsoid
EllipsoidWGS84-
a6378137meter
1/f298.257223563-

Shift
dX-24.0024meter
dY-17.1032meter
dZ-17.8444meter

Rotation
Scale