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EGM96 Geoid

Calculate geoid height as determined from EGM96 Geopotential Model

    Note:   EGM96 Geoid will be removed in a future version. Use Geoid Height instead.

Library

Environment/Gravity

Description

The EGM96 Geoid block calculates the geoid height as determined from the EGM96 Geopotential Model. The block interpolates the geoid heights from a 15 minute grid of point values in the tide-free system. It uses the EGM96 Geopotential Model to degree and order 360. The geoid undulations are with respect to the WGS84 ellipsoid.

The interpolation scheme wraps over the poles to allow for geoid height calculations at and near these locations.

Dialog Box

Units

Specifies the parameter and output units:

Units

Height

Metric (MKS)

Meters

English

Feet

Data type

Specify the data type of the input and output signals. From the list, select double or single.

Inputs and Outputs

InputDimension TypeDescription

First

ScalarContains geocentric latitude in degrees, where north latitude is positive, and south latitude is negative. Input latitude must be of type single or double. If latitude is not in the range from -90 to 90, the block wraps it to be within the range.

Second

ScalarContains geocentric longitude in degrees, where east longitude is positive in the range from 0 to 360. Input longitude must be of type single or double. If longitude is not in the range from 0 to 360, the block wraps it to be within the range.

OutputDimension TypeDescription

First

ScalarContains the geoid height, in meters.

Limitations

This block has the limitations of the 1996 Earth Geopotential Model. For more information, see http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm96/egm96.html.

The WGS84 EGM96 geoid undulations have an error range of +/-0.5 to +/-1.0 meters worldwide.

References

"Department of Defense World Geodetic System 1984, Its Definition and Relationship with Local Geodetic Systems", NIMA TR8350.2.

"The Development of the Joint NASA GSFC and NIMA Geopotential Model EGM96", NASA/TP-1998-206861.

National Geospatial-Intelligence Agency Web site: http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm96/egm96.html

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