Adding an MGRS or a U.S. National Grid

About MGRS and U.S. National Grid

The Military Grid Reference System (MGRS) is a grid-based system used to represent locations on the universal transverse Mercator (UTM) and universal polar stereographic (UPS) grid systems, expressed as an alphanumeric string. An MGRS coordinate defines an area on the Earth's surface as opposed to a specific point. A fully qualified MGRS string is 15 characters long and consists of the following three components: grid zone designation, 100,000-meter square identifier, and easting/northing.

There are two methods for adding an MGRS or U.S. National Grid overlay to your map. If you need a dynamic grid that updates automatically as you pan and zoom, you can use the data frame grid properties with an MGRS or U.S. National Grid overlay grid. However, if you need to do one of the following, you will need to utilize a Grid and Graticule layer:

• Display the MGRS or U.S. National Grid in a coordinate system other than UTM
• Display UTM labels when your area of interest crosses UTM zones
• Display multiple MGRS or U.S. National Grid overlays within a single layout
• Display the MGRS or U.S. National Grid for rotated and nonrectangular areas of interest
• Change the MGRS or U.S. National Grid interval
• Place interior ladder labels for alternate intervals

Grid and Graticule layers support these complex grid and graticule scenarios. However, they are not dynamic and will not update as you pan and zoom.

Learn more about Grid and Graticule layers

Adding an MGRS or a U.S. National overlay grid with wizards turned on

Use the following steps to add an MGRS or a U.S. National Grid to your map layout using Grids and Graticules Wizard. For more information on Grids and Graticules Wizard, see A quick tour of the Grids and Graticules Wizard.

1. Create a default graticule using Grids and Graticules Wizard (see the steps in Adding a graticule).
2. On the Data Frame Properties dialog box, click the Grids tab.
3. Choose the grid you just created and click the Styles button.
4. Click the MGRS or U.S. National Grid style you want to use from the list of grids. This list contains the reference systems in the ESRI style and in any other styles you may have referenced.
5. Click OK to close all dialog boxes.

MGRS overlay grids only appear in layout view. MGRS overlay grids appear correctly only when your data frame is set to a UTM projected coordinate system appropriate for your area of interest. The ESRI style contains some MGRS grid and U.S. National Grid styles for you to use. You can modify these, or you can create your own MGRS grid or U.S. National Grid styles.

Making modifications to the properties of the reference grid will not change it from the MGRS grid or U.S. National Grid style. If you do want to save the changes in a new style, click the Style button, click Save, then specify the name for your new grid.

Tip:

You can change the name of the grid on the Grids tab of the Date Frame Properties dialog box. Click twice on the grid name in the list to put it into edit mode and type the new name.

Adding an MGRS or a U.S. National overlay grid with wizards turned off

Use the following steps to add an MGRS grid or a U.S. National Grid to your map layout without using Grids and Graticules Wizard. For more information on Grids and Graticules Wizard, see A quick tour of the Grids and Graticules Wizard.

1. Click View > Data Frame Properties.
2. Click the Grids tab on the Data Frame Properties dialog box.
3. Click New Grid.
4. Choose the MGRS or U.S. National Grid style you want to use from the list of grids. This list contains the reference systems in the ESRI style and in any other styles you may have referenced.
5. Click OK to close all dialog boxes.

MGRS overlay grids only appear in layout view. MGRS overlay grids appear correctly only when your data frame is set to a UTM projected coordinate system appropriate for your area of interest. The ESRI style contains some MGRS grid and U.S. National Grid styles for you to use. You can modify these, or you can create your own MGRS grid or U.S. National Grid styles.

Making modifications to the properties of the reference grid will not change it from the MGRS grid or U.S. National Grid style. If you do want to save the changes in a new style, click the Style button, click Save, then specify the name for your new grid.

Tip:

You can change the name of the grid on the Grids tab of the Data Frame Properties dialog box. Click twice on the grid name in the list to put it into edit mode and type the new name.

Adding a Grid and Graticule layer for a U.S. National Grid

The Make Grids and Graticules Layer geoprocessing tool creates a grouped layer of feature classes depicting grid, graticule, and border features using predefined cartographic specifications. Grid and Graticule layers are ideal for advanced grid definitions that are scale and extent specific. They are designed for projected maps that will be printed or exported. The tool is not meant for creating grids or graticules that dynamically update as the user navigates the map.

Use the following steps to add a Grid and Graticule layer representing a U.S. National Grid. These steps assume that you have a map document open and already have the data frame zoomed to the desired extent.

Note:

The tool requires that a feature dataset is available before running the tool. This feature dataset must be in the same datum or geographic coordinate system as the grids and graticules that you want to create.

1. Open the Make Grids and Graticules Layer geoprocessing tool.

   You can find the tool by opening Search and typing Make Grids and Graticules Layer, or you can locate the tool under Toolboxes > System Toolboxes > Cartography Tools > Grids and Graticules.

2. Click the Grid Template (XML file) browse button , navigate to the folder containing the XML templates (located under the ArcGIS installation directory \ArcGIS\Desktop10.0\GridTemplates), then choose the USNG XML template you want to use.

   The grid definition template is stored in a predefined XML file. This file stores specification properties for each grid, such as the number, color, and line weight of gridlines. When the definition template is applied, features are created according to the specification based on the current extent or extent of a selected feature (area of interest), scale and coordinate systems.

   Tip:

   Templates supporting the U.S. National Grid have names beginning with "USNG."

3. Specify a value for Input Area of Interest by choosing Extent, clicking the arrow, then choosing Same as Display.

   The Input Area of Interest can also be based on a polygon feature from a chosen layer or on a specified extent.

4. Click the Input Feature Dataset browse button and navigate to the feature dataset in which you want to store the Grid and Graticule layer features.

   Grid and graticule features are saved to this feature dataset for future use. You can use this feature dataset to hold grids and graticules for other areas. If you do, make sure you use unique names to distinguish between the different sets.

5. Specify the Output Layer name.

   This is the in-memory layer that is added to the active data frame as a result of geoprocessing.

6. Click Advanced Settings.
7. Check the Configure data frame and layout using grid settings check box.

   When this is checked, the tool adjusts the data frame settings to ensure they match the grid layer. The data frame's coordinate system, scale, rotation, size, and extent may be altered to enforce consistency. The data frame may also be clipped.

   Caution:

   This setting is only available when the tool is executed from the ArcMap layout view and is not being run in the background.

8. Click OK.

Once a grid is generated, changing the data frame's coordinate system may cause unexpected results. Since these grids are features and spatially accurate, if you project a grid that was created using a cylindrical projection, for example, UTM or Mercator, and you change your coordinate system to a conic or equal area projection, the grid lines will curve and warp with the coordinate transformation. The grids are still accurate for the projection for which they were generated but may no longer meet at right angles. Also coordinate annotation will be projected that may cause conflicts and reduce the quality of your coordinate label placement. You may need to move the annotation manually.