Geocode

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GEOCODEs are used by PANGAEA to geo-reference the origin of data values in space and time on earth. In the data numeric and data text tables of Pangaea, each value is geo-referenced, using some of the geocodes listed below. Geocodes are defined in the parameter table written in capital letters. They are defined as float values and thus can be configured to any precision (exception: DATE/TIME is defined as a Datum-field). The geocode not only defines the third numeric dimension from where a certain value was measured, but also in which medium the value was measured.

Most important and mandatory geocodes for georeferenced data are the geographical coordinates (ID in brackets, examples as DOI):

  • LATITUDE (1600)
  • LONGITUDE (1601)
    • For data sets from a single location the coordinated latitude and longitude are defined through the event doi:10.1594/PANGAEA.133415 .
    • For data sets from many locations or horizontal profiles a fully georeferenced data set is imported, which contains the coordinates (in decimal degree) for each line in two columns.

For the third spatial dimension the system provides different options. Only one of the following geocodes can be used in a data set:

  • DEPTH, depending on the origin of the data use:
  • ELEVATION [m] (8128) for samples taken on the earth surface, relative to sea level (above s.l. + positive, below s.l. - negative)
  • ALTITUDE [m] (4607) for measurements in meter above sea level, i.e. in the air; example: doi:10.1594/PANGAEA.385121
  • HEIGHT above ground [m] (56349) for measurements in meter above ground (not above sea level)

The following are not real spatial geocodes, but may be used to force data in a certain order:

  • DISTANCE [cm] (2920) relative measure in an object, e.g. coral, tree, shell, nodule
  • POINT DISTANCE from start [m] (26097) relative distance along a horizontal transect
  • SECTION, height [m] (25539) relative hight of a vertical profile
  • ORDINAL NUMBER (6262) may be used, if no third dimension is given and samples should just kept in order.

A data set can only have one vertical spatial geocode but may also have a time geocode:

  • AGE [kyr] (2205) for geological ages
    • Age, minimum/young (6167) and
    • Age maximum/old (6168) are NOT geocodes but may be used if a time span needs to be defined more precisely.
  • DATE/TIME (1599) for time series. The export format follows the ISO-standard 8601; example: 2006-02-18T14:45:41. Any fraction of the full ISO can be defined on the config card of a data set in the format menue. Also format for week of the year (YYYY-Www) and quartal of the year (YYYY-Qq) are provided. If a relative time is needed, e.g. for experiments, use hh:mm:ss. The DATEPART-formats will reduce a date to e.g. year or day.

For the import of events, date and time are in two fields and should have the format as defined through the operating system. When importing data sets, date/time are given in one field/column (headed by the ID 1599) and may have any valid format. DATE/TIME is defined in Sybase as a date/time-field and thus any format will be accepted and automatically converted to ISO.

The following additional date parameters are NOT geocodes but may be used if more date/time fields are required to precisely define a time span. Both are just text parameters and thus date/time should be imported already in the appropriate ISO-format.

  • Date/time start (7020) and
  • Date/time end (7021)
  • Date (16047)

The list of GEOCODEs can be downloaded from Pangaea in html or text format.

Retrieved from "http://wiki.pangaea.de/wiki/Geocode"
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