Add a topographic north arrow

Disponible avec une licence Defense Mapping.

Topographic north arrow elements are declination diagrams that represent three ways of defining north:

• Grid north (GN)—The north established using the vertical grid lines on the map. Grid north is automatically calculated based on the center point of the chosen map frame.
• Magnetic north (MN)—The direction to the north magnetic pole, as indicated by the north-seeking needle of a magnetic instrument. It is symbolized by a line ending with half an arrowhead. Magnetic north is automatically calculated based on the center point of the chosen map frame and the selected date.
• True north—A line from any point on the earth's surface to the north pole. All lines of longitude are true north lines. It is represented by a star at the end of a line.

Insert a topographic north arrow

A topographic north arrow can be inserted on any map layout.

1. Verify that the map is in layout view.

   If you don't have a layout set up for your project, add a layout.

2. Click the Insert tab.
3. Click the North Arrow drop-down arrow and choose a north arrow in the Topographic group.

   The north arrow is added to the layout.

   Remarque :

   The text defaults to Zurich Cn BT. If you do not have the Zurich Cn BT font installed, the text defaults to Arial.

Modify a topographic north arrow

You can modify the properties and appearance of the north arrow using either the Format tab on the ribbon or the Format North Arrow pane.

Remarque :

The size commands aren't available for this element because its size is fixed to meet map product specifications.

The following properties are available for north arrows only in the Format North Arrow pane.

The name of the north arrow can be changed by typing a new name in the Name text box. The name of the element appears in the Contents pane and must be unique.

The north arrow can be hidden by unchecking the Visible check box. The default is visible.

The north arrow can be locked to prevent changes from being made by checking the Locked check box. The default is unlocked.

The map frame a north arrow is associated with can be changed by choosing a new map frame from the drop-down list in the North Arrow section of the Element pane.

You can modify the date used to calculate the declination of magnetic north by unchecking the Update Dynamically check box, clicking the Declination Date drop-down arrow in the Declination group, and choosing the declination date you want to use. The magnetic value is calculated using the World Magnetic Model, which is released in five-year epochs. If the chosen date is outside of the supported epochs, the date is automatically set to the closest date available.

You can modify the coordinate system used to calculate the declination of grid north by unchecking the Update Dynamically check box, clicking the Coordinate System button in the Declination group, and choosing a coordinate system.

Remarque :

When the map on the map frame uses a projected coordinate system, the element automatically calculates the universal transverse Mercator (UTM) zone for the map. If the map covers two UTM zones, use the Primary Coordinate System check box to switch between the two zones.

You can manually define the G-M Angle and Grid Convergence options by unchecking the Update Dynamically check box, expanding the appropriate group, and updating the following settings:

• Direction—Choose West or East.

  When the Directional Notes check box is checked, the West or East text is capitalized and added to both the G-M and G-T notes, for example, 1½° (30 MILS) WEST.

• Degrees—Type or choose the number of degrees you want to use. The Mils value is automatically updated with the corresponding value in mils.

  When the Round G-M Angle check box is checked, the G-M angle is displayed to the nearest half-degree. For example, 13 ½°; mils are displayed to the nearest 10 mils, or 240. If the Round G-M Angle check box is unchecked, the G-M angle is displayed as degrees and minutes. For example, 13°41’; mils are displayed to the nearest 1 mil, or 243, and leading zeros are not displayed for G-M minutes.

• Minutes—Type or choose the number of minutes you want to use.

  When the Leading Zeros check box is checked, leading zeros are displayed for G-C minutes.

• Mils—Type or choose the number of mils you want to use. The Degrees and Minutes values are automatically updated with the corresponding values.

  When the Round Mils check box is unchecked, mils for both G-C and G-M are shown in decimals, for example, 19.6. This option is unavailable when the Round G-M Angle check box is checked.