Layer Structure

GIS systems use a layer structure to organise the data. Likewise, Web mapping also arranges our base data, and then layers other contextual data over the top.

Base Layers

Base layers are normally made up of raster data, such as satellite imagery, digital elevation models (DEMS), hillshades or a combination of both raster and vector data.

You can toggle between base layers as you use the map. Examples of base layers available in Operations GIS are listed below:

Layer	Description
Hillshade and Bathymetry	Antarctic hillshade and bathymetry south of 60°S
LIMA mosaic	Landsat Image Mosaic of Antarctica (LIMA). True colour (bands 3, 2, 1), pan-sharpened. Imagery dated 1999-2003. (learn more here)
REMA DEM	Reference Elevation Model of Antarctica, a Digital Surface Model (DSM) at 8-meter spatial resolution from the Polar Geospatial Center (PGC)

Operations GIS with base layers highlighted. As you can see, Radarsat RAMP HH is toggled here.

Reference Layers

The rest of the layers are called Reference Layers, and contain a mixture of Topographic and Operations data.

Topographic Data

Topographic data layers are sourced from the Antarctic Digital Database.

The ADD is updated twice a year and is available for download here. At Rothera, the data is updated at the start of each season.

Operations GIS, highlighting the topographic data layer group

Operations Data

This data is split into Static Data, which is useful reference data that is relatively fixed, and Season Data, which is updated annually.

Static Data

Examples of static operations data include station-specific data such as Rothera building layout, the Dash-7 PNR radii from airfields, or multi-year tractor traverse routes.

Operations GIS, highlighting the static data. Notice we have toggled the "Primary Routes and Waypoints" data layer here.

Season Data

Season data is updated annually, and usually includes:

• Waypoints, Depots and Network routes from the Air Operations Planning Maps

• Science Sites sourced from the Field Operations Manager

Operations GIS, highlighting the season-specific data group.