Date (Creation)

2024-10-15

Date (Revision)

2024-10-15

Date (Publication)

2024-10-15

Date (released)

2024-10-15

Edition

1.0

Unique resource identifier

https://doi.org/10.5285/386eef1f-2dc7-413c-8ff4-c90722c047f4

Codespace

doi

Unique resource identifier

GB/NERC/BAS/PDC/01919

Codespace

https://data.bas.ac.uk/

Other citation details

Please cite this item as: Fenney, N., & Gerrish, L. (2024). Topographic contours of Signy Island (March 2015) (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/386eef1f-2dc7-413c-8ff4-c90722c047f4

Credit

No credit.

Status

Completed

Point of contact

Organisation name	Individual name	Electronic mail address	Role
British Antarctic Survey	Fenney, Nathan		Author
British Antarctic Survey	Gerrish, Laura		Author
NERC EDS UK Polar Data Centre		PDCServiceDesk@bas.ac.uk	Point of contact

Maintenance and update frequency

As needed

Maintenance note

Completed

Global Change Master Directory (GCMD) Science Keywords

• EARTH SCIENCE > Land Surface > Topography > Contours

Theme

• Signy Island

• South Orkney Islands

• photogrammetry

• topographic contours

Place

• Signy Island Antarctica

• South Orkney Islands Antarctica

GEMET - INSPIRE themes, version 1.0

• Land cover

Access constraints

Other restrictions

Other constraints

no limitations to public access

Access constraints

Other restrictions

Other constraints

no limitations

Use constraints

License

Other constraints

Open Government Licence v3.0

Use constraints

Other restrictions

Other constraints

Data supplied under Open Government Licence v3.0

Use constraints

Other restrictions

Other constraints

None

Unique resource identifier

url

Codespace

url

Association Type

Larger work citation

Unique resource identifier

url

Codespace

url

Association Type

Cross reference

Unique resource identifier

url

Codespace

url

Association Type

Cross reference

Spatial representation type

Text, table

Language

English

Character set

UTF8

Topic category

• Boundaries
• Elevation
• Geoscientific information

Begin date

2015-03-29

End date

2015-03-29

Supplemental Information

It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk.

Title

European Petroleum Survey Group (EPSG) Geodetic Parameter Registry

Date (Publication)

2008-11-12

Cited responsible party

Organisation name	Individual name	Electronic mail address	Role
European Petroleum Survey Group		EPSGadministrator@iogp.org	Publisher

Unique resource identifier

urn:ogc:def:crs:EPSG::3031

Version

6.18.3

Hierarchy level

Dataset

Statement

Methodology:

Photogrammetry and terrain extraction:

The stereo VHR satellite images were processed in Socet GXP. Image triangulation was undertaken using a combination of known ground control points and automatically generated tie points. Following image triangulation, a digital elevation model was extracted using an automatic terrain extraction algorithm. The resulting digital elevation model was then compared with the original imagery using a stereoscopic monitor. Where the digital elevation model deviated from the imagery, these deviations were corrected manually. The digital elevation model was then exported from Socet GXP as a georeferenced .tif file.

WorldView-3 satellite images (c) 2015 Maxar Technologies.

Contour extraction:

Contours were extracted from the above digital elevation model using the 'Contour' tool in ArcGIS Pro v3.3.0 with a 10 metre interval. All anomalous contours less than 10 m in elevation were deleted, and any lines with a length less than 10 m were also deleted.

Coordinate reference system:

The projected coordinate system is WGS84 UTM Zone 23S.

Dataset Fields:

The dataset has an attribute field displaying the contour elevation related to Mean Sea Level (MSL) at Signy Research Station. Signy MSL is defined in the following report, BAS Archive reference no. AD6/2H/2001/L1 'GPS Survey Field Report - 2001-02 Antarctic Field Season', but to summarise: MSL is defined by the tide gauge at Signy Station. To transform data from WGS84 to Signy MSL, apply a local correction factor of -32.235 m (MSL is below WGS84). To access the full field report, please contact British Antarctic Survey Archives service.

Data collection:

Source imagery:

In-Track stereo WorldView-3 (MAXAR) VHR (very high resolution) satellite imagery.

WorldView-3 satellite images © 2015 Maxar Technologies.

Photogrammetry software:

Socet GXP (version 4.5.1.5)

GIS software:

ArcGIS Pro (version 3.3.0)

Data quality:

Image triangulation during the Socet GXP photogrammetric workflow was undertaken using a combination of ground control points and automatically generated tie points. The ground control points provided a global geospatial reference and were sourced from an earlier GNSS (global navigation satellite system) survey conducted around Signy Island during the 2001/02 Antarctic field season.

Identifying the original ground control points proved challenging due to the limited resolution of the satellite imagery and the duration of time that had passed between the original GNSS survey and the satellite capture. Points that could not be identified or no longer existed were removed.

The average error across the remaining ground control points following image triangulation was around 0.5 m.

Please refer to the original field report for an estimation of accuracy of the individual ground control points. BAS Archive reference no. AD6/2H/2001/L1 'GPS Survey Field Report - 2001-02 Antarctic Field Season'.

Please note, the additional error created as a result of the terrain extraction and contour creation workflows will vary across the dataset and has not been formally calculated but is expected to be around 2 - 3 m.

Metadata

File identifier

386eef1f-2dc7-413c-8ff4-c90722c047f4 XML

Metadata language

English

Character set

UTF8

Hierarchy level

Dataset

Hierarchy level name

dataset

Date stamp

2024-10-15

Metadata standard name

ISO 19115 Geographic Information - Metadata

Metadata standard version

ISO 19115:2003(E)

Metadata author

Organisation name	Individual name	Electronic mail address	Role
NERC EDS UK Polar Data Centre		polardatacentre@bas.ac.uk	Point of contact