position.yml

title: Position
description: >
  Information about a position during sampling.
  Since the platform moves during sampling, these positions often represent the calculated 
  midpoint of a trajectory.
  These trajectories (also called "observation bins") typically have a predefined duration (e.g. 2 
  minutes).
fields:
  - name: RecordType
    description: >
      Record type.
      Use `EP` for position records.
    type: string
    constraints:
      required: true
      pattern: 'EP'

  - name: SampleID
    description: >
      Identifier of the sample the position belongs to.
    type: string
    constraints:
      required: true
      maxLength: 50

  - name: PositionID
    description: >
      Identifier of the position.
      Must be unique within the campaign.
    type: string
    constraints:
      required: true
      unique: true
      maxLength: 50

  - name: Time
    description: >
      UTC time at the start of the trajectory/observation bin of this position, formatted as `hh:mm:ss`.
    type: time
    constraints:
      required: true

  - name: Latitude
    description: >
      Latitude of the position in decimal degrees, using the WGS84 datum.
      Often the calculated midpoint of a trajectory.
    type: number
    constraints:
      required: true
      minimum: -90
      maximum: 90

  - name: Longitude
    description: >
      Longitude of the position in decimal degrees, using the WGS84 datum.
      Often the calculated midpoint of a trajectory.
    type: number
    constraints:
      required: true
      minimum: -180
      maximum: 180

  - name: Distance
    description: >
      Distance (in km) travelled during the observation bin.
      Can only remain empty if `Area` is used.
    type: number
    constraints:
      required: false

  - name: Area
    description: >
      Area (in km²) of sea surveyed during the observation bin.
      Can only remain empty if `Distance` is used.
    type: number
    constraints:
      required: false

  - name: WindForce
    description: |
      Wind force and sea state according to the Beaufort scale.

      - `0` Calm - Sea like mirror
      - `1` Light air - Ripples with appearance of scales, no foam crests
      - `2` Light breeze - Small wavelets, crests of glassy appearance, not breaking
      - `3` Gentle breeze - Large wavelets, crests begin to break, scattered whitecaps
      - `4` Moderate breeze - Small waves becoming longer, numerous whitecaps
      - `5` Fresh breeze - Moderate waves, many whitecaps, some spray
      - `6` Strong breeze - Larger waves, whitecaps everywhere, more spray
      - `7` High wind, moderate gale, near gale - Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind
      - `8` Gale, fresh gale - Moderately high waves; edges of crests begin to break into the spindrift; foam is blown in well-marked streaks along the direction of the wind
      - `9` Strong/severe gale - High waves; dense streaks of foam along wind; crests begin to topple, tumble and roll over; spray may affect visibility
      - `10` Storm, whole gale - Very high waves with long overhanging crests; foam in great patches blown in dense white streaks along wind; sea surface takes a white appearance; tumbling becomes heavy and shock-like; visibility affected
      - `11` Violent storm - Exceptionally high waves (medium sized ships may be lost to view behind waves); sea covered with long white patches of foam lying along the wind; everywhere edges of crests are blown into froth; visibility affected
      - `12` Hurricane force - Air is filled with foam and spray; sea completely white with driving spray; visibility seriously affected
    type: string
    vocabulary:
      text: Beaufort
      href: http://vocab.ices.dk/?ref=1705
    constraints:
      required: false
      enum:
        - '0'
        - '1'
        - '2'
        - '3'
        - '4'
        - '5'
        - '6'
        - '7'
        - '8'
        - '9'
        - '10'
        - '11'
        - '12'

  - name: Visibility
    description: |
      Visibility (in km).
      Use a range code (`A`-`D`) for historical data.

      - `A` Poor (< 1 km) or express as `0.1`, `0.2`, `0.3`, ...
      - `B` Fair/moderate (1 - 5 km) or express as `1`, `1.5`, ...
      - `C` Good/very good (5 - 10 km) or express as `5`, `6`, ...
      - `D` Excellent/infinity (> 10 km) or express as `10`
    type: string
    vocabulary:
      text: Visibility
      href: http://vocab.ices.dk/?ref=1708
    constraints:
      required: false
      enum:
        - '0.1'
        - '0.2'
        - '0.3'
        - '0.4'
        - '0.5'
        - '0.6'
        - '0.7'
        - '0.8'
        - '0.9'
        - '1'
        - '1.5'
        - '2'
        - '2.5'
        - '3'
        - '3.5'
        - '4'
        - '5'
        - '6'
        - '7'
        - '8'
        - '9'
        - '10'
        - A
        - B
        - C
        - D

  - name: Glare
    description: |
      Glare that could be affecting observation quality.

      - `none` No glare
      - `weak` Weak glare (no major effect on the counting)
      - `medium` Medium glare (a part of the viewing area is affected by glare)
      - `strong` Strong glare (the whole viewing area is affected)
    type: string
    vocabulary:
      text: Glare
      href: http://vocab.ices.dk/?ref=1717
    constraints:
      required: false
      enum:
        - none
        - weak
        - medium
        - strong

  - name: SunAngle
    description: >
      Angle of the sun in relation to the observer (`0`-`359`), with `0` being straight ahead.
    type: integer
    constraints:
      required: false
      minimum: 0
      maximum: 360

  - name: CloudCover
    description: >
      Cloud cover (in oktas).
    type: string
    vocabulary:
      text: CloudCover
      href: http://vocab.ices.dk/?ref=1706
    constraints:
      required: false
      enum:
        - '0'
        - '1'
        - '2'
        - '3'
        - '4'
        - '5'
        - '6'
        - '7'
        - '8'

  - name: Precipitation
    description: |
      Precipitation.

      - `N` None
      - `R` Rain
      - `S` Snow
      - `F` Fog
    type: string
    vocabulary:
      text: Precipitation
      href: http://vocab.ices.dk/?ref=1707
    constraints:
      required: false
      enum:
        - 'N'
        - 'R'
        - 'S'
        - 'F'

  - name: IceCover
    description: >
      Ice cover percentage within the transect.
    type: integer
    constraints:
      required: false
      minimum: 0
      maximum: 100

  - name: ObservationConditions
    description: |
      General impression of the observation conditions.
      
      - `G` Good
      - `M` Moderate
      - `P` Poor
    type: string
    vocabulary:
      text: Sightability
      href: https://vocab.ices.dk/?ref=1704
    constraints:
      required: false
      enum:
        - G
        - M
        - P

missingValues:
  - ''
  - NA
primaryKey: PositionID
foreignKeys:
  - fields: SampleID
    reference:
      resource: samples
      fields: SampleID