Antarctic Digital Database/Data

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This page describes the geographic data available from the Antarctic Digital Database and the plans for translating this into OSM form for import.

Coastlines

The coastlines layer of the ADD contains the coastline and ice shelf data. It consists of:

  • line strings with attributes indicating coast type as well as data source information
  • separate polygons for: land, ice shelf, ice tongue, rumple, ocean
  • historic ice coastline data (probably not useful for OSM)

Feature translations

ADD layer feature type cst00_srf Description OSM Tag(s)
coast area land Land areas place=island, except for main land mass
coast area ice shelf Ice shelves natural=glacier, glacier:type=shelf
coast area rumple Broken up ice natural=glacier, glacier:type=shelf
coast area ice tongue Glacier ice tongues natural=glacier, glacier:type=ice_tongue
coast area ocean Open water areas in ice shelves natural=water, water=epishelf_lake
coast area Open ocean (not in the original data, necessary for processing) natural=water, fixme=remove before upload
coast way edge between land and ocean natural=coastline
coast way edge between ice shelf and ocean natural=coastline, glacier:edge=calving_line
coast way edge between land and ice shelf glacier:edge=grounding_line

Line attributes

ADD attributes Description OSM Tag(s)
cst00typ Feature type code, see [1]
cst00dat Date survey:date=*
cst00inf Information text note=*
cst00src Data source source=*
cst00rev Revision date source:date=*
cst00edt Editor
cst00sht Map sheet

Rock outcrops

This layer maps the ice free areas on land. Although these areas are primarily rocky they are not exclusively solid rock. No further distinction of surface type is made.

Data consists of:

  • polygons of the ice free areas
  • corresponding line strings containing data source information

The data does not well match the other features in the database and to mitigate this problem the rock areas have been buffered by 2.5 meters on the islands and clipped with the coastlines afterwards. This introduces a slight bias which is well below the data accuracy though and doing this avoids many artefacts.

Feature translations

ADD layer feature type Description OSM Tag(s)
rock area Rock area without ice natural=bare_rock

Line attributes

To avoid overlaps with other features the rock outcrop polygons need to be clipped and line attributes can not be easily maintained in this process.

Moraines

In contrast to other other area features in ADD there is no separate line string data for the moraines layer. But there is a distinction in form of the mrn00sub attribute to distinguish moraines on glaciers and off glaciers.

Feature translations

ADD layer feature type mrn00sub Description OSM Tag(s)
moraine area ice moraine on glacier natural=glacier, geological=moraine
moraine area other moraine off glacier natural=scree, geological=moraine
moraine area * moraine on ice shelf surface=scree, geological=moraine overlapping the ice shelf multipolygon

Lakes

This layer maps inland water surfaces. No further distinction is made (sweet/saltwater, frozen or ice free)

Feature translations

ADD layer feature type Description OSM Tag(s)
lakes area Lakes natural=water, water=lake

The lake polygons are split when they extend across the grounding line but no difference is made in tagging.

Line attributes

To avoid overlaps with other features the lake polygons need to be clipped and line attributes can not be easily maintained in this process.

Streams

This layer maps flowing water. Since all of these are relatively small and usually dry/frozen for most of the year they are tagged waterway=stream.

Since way direction is not consistently downstream in the ADD data direction has been set based on RAMP DEM. This is not perfect either so manual verification would be useful.

Feature translations

ADD layer feature type Description OSM Tag(s)
streams way Water Streams waterway=stream, intermittent=yes

Locations of research stations, camps and airfields

The point data for research stations, camps etc. in the ADD comes with various additional attributes, translation into OSM tags is described in the following. Note these will need to be carefully merged with the existing POI data in OSM. since Camp seems to be a very broad classification adding a fixme seems appropriate.

Feature translations

ADD layer feature type feature_ty OSM Tag(s)
human node Camp place=isolated_dwelling, fixme=verify classification of place
human node Depot amenity=depot
human node Refuge amenity=shelter
human node Aerodrome aeroway=aerodrome
human node Station place=hamlet

Attribute translations

ADD attributes Description OSM Tag(s)
hmn00elv Elevation ele=*
hmn00nam Name name=*
notes Description description=*
hmn00nat Operating nation operator=*
capacity Station/camp capacity capacity:persons=*
if either status or temporal contains Seasonal seasonal=yes
if temporal contains Year-round seasonal=no
if status contains Abandoned abandoned=yes
if either status or temporal contains Temporarily closed disused=yes

historic sites

Historic site data in the ADD is somewhat different from the other data. There is essentially only a brief and a longer description for these points so classification is based on keywords in those texts (priority in the order of the table)

Feature translations

Keyword OSM Tag(s)
plaque historic=memorial
cemetery historic=tomb
grave historic=tomb
cross historic=wayside_cross
hut historic=ruins
cairn historic=cairn

Attribute translations

ADD attributes OSM Tag(s)
brief_desc description=*
full_descr note=*

Contour lines and point elevations

Contour lines are by convention not part of the OSM data and the point elevations have no additional attributes indicating peaks or other features so they are not of interest either.