Help for Christmas Island Online GIS


Outline

Christmas Island Online GIS is a web based map system for exploring Christmas Island over the internet. The system allows you to zoom in and out, pan and select attributes of displayed themes. Themes can be activated/deactivated from the tick-boxes on the right hand side of the site.


  • This page is best viewed at at least 1024 x 768 resolution, with at least 16 million colours.

Basic Navigation

CIGIS uses 4 basic buttons for navigating Christmas Island:

  • Zoom In - This button is for zooming in. Select this button, drag a box in the main map and the view will redraw, zoomed in to the selected box. The minimum scale at which a map will draw is 1:500. In the non-java version, click on a point rather than drag a box.

  • Zoom Out - This button is for zooming out. Select this button, click on a point in the main map and the view will redraw, zoomed out with the selected point in the centre of the view. The maximum scale at which a map will draw is 1:150 000.


  • Pan - This button is for panning (recentering the map). Select this button, click on a point in the main map and the view will redraw, with the selected point in the centre of the view.


  • Query - This button is for querying displayed features. Select this button, click on a feature in the main map and attributes of the selected feature will be displayed in a popup window.

The menu on the right allows the user to select multiple themes to overlay on the map. Click Update Map to apply changes to theme selection.

The reference map, in the bottom right hand corner of the screen, shows the location of the view (displayed as a yellow rectangle) in relationship to the full map extents. You may navigate roughly to a particular place on the island by clicking on the reference map then use Pan to navigate more precisely to the desired location.


Additional Information

The minimum scale at which a map will draw is 1:500. The maximum scale at which a map will draw is 1:150 000.

The legend button loads the legend in a different window that shows the colours of all displayed themes and their associated label values.

The projection of all data is CIG85, zone 48, Datum WGS72. “CIG85 is a plane rectangular grid coordinate system with True Origin coinciding with a point at UTM GRID ZONE 48 coordinates 570 000mE and 8 840 000mN (WGS 72). At that point the false origin is 20 000mW and 60 000mS of True Origin”

You can change the size of the output image by selecting an image size in pixels from the drop down box, located under the main map.


Note: Larger maps take longer to download.