Coordinate Systems

WMS allows the user to convert data to/from several coordinate systems. Mesh, map, scatter, image, and grid data can be converted to/from both horizontal and vertical systems. The Coordinate Conversions page describes how to set these systems. The available systems and units include:

Horizontal System

Set the horizontal system. The options to the right of the dialog change as the horizontal system is changed. For example, the hemisphere is required for a Geographic system and a UTM zone is required for a UTM system.

Local is the default horizontal and vertical system. Unless the user desires to convert data to another system, it is not necessary to change the system from Local.

Horizontal Units

Set the horizontal units (listed below). This options is available for all systems except Geographic, which uses decimal degrees. The units set here are the units used by the models such as RMA2.

Ellipsoid

The Ellipsoid options is only available for non-NAD/HPGN systems. The ellipsoid can be selected for a region of the world. Changing the ellipsoid changes the minor and major radii of the earth, measurements used in performing conversions. To set the radii for an ellipsoid not included in WMS, select the User Defined ellipsoid and a button appears titled Define. Clicking on this button brings up a dialog where the radii are defined.

Vertical System

Set the vertical system. The supported vertical data are for North America. If a non-NAD/HPGN horizontal system is selected, this option is disabled.

Vertical Units

Set the vertical units (listed below). The vertical unit is only used for conversions. Area and volume calculations done by WMS use the horizontal units.

 

Related Topics:
Single Point Conversion

Coordinate Conversions