This repository contains R scripts and resources used by the CCAMLR Secretariat to generate spatial objects, as well as examples of their use. Many of the operations rely on the CCAMLRGIS R package which functions may be accessed and reviewed here.
The following rules, as endorsed by the Scientific Committee in 2023 (SC-CAMLR-42, paragraph 2.30), will be applied throughout. The rules will be updated if requested by the Scientific Committee.
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geographical information system (GIS) objects use the EPSG 6932 projection (South Pole Lambert Azimuthal Equal-Area projection),
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lines of more than 0.1 degree of longitude be densified,
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polygon vertices be given clockwise in decimal degrees with at least five decimal places,
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vertices be added where polygons meet (see WG-FSA-2023 Figure 1),
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inland vertices be used for polygons that are bound by any coastline (continent and islands),
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polygons be clipped to all coastlines (continent and islands) based on the most recent available coastline data,
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the coastline be based on the latest available coastline data, as obtained from the SCAR Antarctic Digital Database (ADD) and other sources where needed (e.g., www.naturalearthdata.com),
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analyses cite CCAMLR geospatial data (i.e., shapefiles) as CCAMLR. (Year). Geographical data layer: (Layer name). Version (Version), URL: (URL),
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all maps cite data sources and projection used.
This section provides access to a basic example of the steps that must be followed when building polygons while adhering to the Geospatial Rules. This workflow is available here.
This section describes the geospatial workflow used by the CCAMLR Secretariat to build and maintain spatial objects for use by CCAMLR Members and the public. It provides methodological details, examples and R scripts to act as a transparent portal to the processes established by the Secretariat. While these resources are available here, individuals looking for the corresponding data should access these from here: https://github.com/ccamlr/data
This section provides access to several numerical tools that are used by the Secretariat when conducting geospatial analyses. Some are in development while others have been used for specific purposes, and all can be accessed here.