Physical oceanography during ALKOR cruise AL594
type: Dataset
conforms to: http://mlcommons.org/croissant/1.0
creator: Thorsten B H Reusch
creator: Felix Mittermayer-Schmittmann
  type: Person
  family name: Mittermayer-Schmittmann
  given name: Felix
  affiliation: GEOMAR - Helmholtz Centre for Ocean Research Kiel
creator: Julia Finke
  type: Person
  family name: Finke
  given name: Julia
  affiliation: GEOMAR - Helmholtz Centre for Ocean Research Kiel
creator: Andreas Lehmann
publisher: PANGAEA
  type: Organization
  disambiguating description: Data Publisher for Earth & Environmental Science
included in data catalog: PANGAEA
  type: DataCatalog
  disambiguating description: Data Publisher for Earth & Environmental Science
date published: 2026-07-31
additional type: dataset
description: Conductivity-temperature-depth profiles were measured using a ADM-CTD SN MOCNET during RV ALKOR cruise AL594. The CTD was equipped with duplicate sensors for temperature, conductivity and oxygen. The oxygen sensor (galvanic oxygen micro-sensor (AMT)) was exchanged in the beginning of the year. The sensors are used throughout the year and no post-cruise calibration is applied. All other sensors of the CTD are calibrated irregularly. Data were connected to the station book of the specific cruise as available in the DSHIP database. […]
abstract: Conductivity-temperature-depth profiles were measured using a ADM-CTD SN MOCNET during RV ALKOR cruise AL594. The CTD was equipped with duplicate sensors for temperature, conductivity and oxygen. The oxygen sensor (galvanic oxygen micro-sensor (AMT)) was exchanged in the beginning of the year. The sensors are used throughout the year and no post-cruise calibration is applied. All other sensors of the CTD are calibrated irregularly. Data were connected to the station book of the specific cruise as available in the DSHIP database. This dataset presents conductivity–temperature–depth (CTD) profiles collected during the research cruise. The data were processed using a custom Python workflow designed to summarize, standardize, and prepare CTD measurements for publication. Raw sensor output files (.TOB format) were parsed using a dedicated reader that extracts header metadata and harmonizes variable naming conventions across all profiles. Quality control procedures included the removal of non-physical values, treatment of missing or malformed entries, and consistency checks across key variables such as pressure, temperature, conductivity, and derived parameters (e.g., salinity and oxygen). Oxygen values were scaled, and salinity values were corrected according to the respective CTD calibration. Sensor channels were standardized and renamed to ensure compatibility with common data standards. Geographic coordinates were converted from degrees and minutes to decimal degrees to improve geospatial usability. Pressure was linearly interpolated to a uniform 1 dbar grid, and all depth-dependent parameters were interpolated accordingly. Maximum recorded pressure was cross-checked against local bathymetry (elevation); in cases of mismatch, profiles were truncated at the maximum depth of the corresponding location. The workflow further includes visual quality control of oxygen saturation, station locations, and vertical profiles of temperature, salinity, and oxygen.
citation: Baltic Cod, Cruise No. AL594, 13 May - 27 May 2023, Kiel (Germany) - Kiel (Germany)
spatial coverage: Place
  geo: GeoShape
    box: 54.13996333 10.02005667 55.79190833 16.50055167
    elevation: -96.0m/-12.0m
temporal coverage: 2023-05-13T07:33:41/2023-05-26T02:07:23
size: QuantitativeValue
  value: 43803.0
  unit text: data points
variable measured: Event label
variable measured: Station label
variable measured: DATE/TIME
  type: PropertyValue
  subject of: DefinedTermSet
    has defined term: Time
variable measured: LATITUDE
variable measured: LONGITUDE
variable measured: Sample elevation
  type: PropertyValue
  unit text: m
  subject of: DefinedTermSet
    has defined term: Length
variable measured: Date/Time local
variable measured: Pressure, water
  type: PropertyValue
  unit text: dbar
  measurement technique: CTD
  subject of: DefinedTermSet
    has defined term: Pressure
    has defined term: water
    has defined term: Energy Density
    has defined term: Force Per Area
    has defined term: CTD
    has defined term: CTD & XBT
variable measured: Temperature, water
  type: PropertyValue
  unit text: °C
  measurement technique: CTD
  subject of: DefinedTermSet
    has defined term: Temperature
    has defined term: water
    has defined term: CTD
    has defined term: CTD & XBT
variable measured: Salinity
  type: PropertyValue
  measurement technique: CTD
  subject of: DefinedTermSet
    has defined term: salinity
    has defined term: CTD
    has defined term: CTD & XBT
variable measured: Conductivity
  type: PropertyValue
  unit text: mS/cm
  measurement technique: CTD
  subject of: DefinedTermSet
    has defined term: conductivity
    has defined term: CTD
    has defined term: CTD & XBT
variable measured: Oxygen
  type: PropertyValue
  unit text: µmol/l
  measurement technique: CTD
  subject of: DefinedTermSet
    has defined term: oxygen
    has defined term: Molar Concentration
    has defined term: CTD
    has defined term: CTD & XBT
variable measured: Oxygen saturation
  type: PropertyValue
  unit text: %
  measurement technique: CTD
  subject of: DefinedTermSet
    has defined term: Dimensionless Ratio
    has defined term: CTD
    has defined term: CTD & XBT
keywords: Baltic Sea; CTD casts; RV ALKOR; Timeseries
license: https://creativecommons.org/licenses/by/4.0/
conditions of access: unrestricted
is accessible for free: true
language: en
distribution: data matrix.tab
distribution: FileObject
  type: DataDownload
  encoding format: text/html

Thorsten B H Reusch
type: Person
family name: Reusch
given name: Thorsten B H
affiliation: GEOMAR - Helmholtz Centre for Ocean Research Kiel

GEOMAR - Helmholtz Centre for Ocean Research Kiel
type: Organization
alternate name: GEOMAR

Andreas Lehmann
type: Person
family name: Lehmann
given name: Andreas
affiliation: GEOMAR - Helmholtz Centre for Ocean Research Kiel

Baltic Cod, Cruise No. AL594, 13 May - 27 May 2023, Kiel (Germany) - Kiel (Germany)
type: CreativeWork
type: Report
report number: AL594
creator: Thorsten B H Reusch
date published: 2024
pagination: 24 pp
is part of: Alkor-Berichte, GEOMAR Helmholtz Centre for Ocean Research, Research Division Marine Ecology/Marine Evolutionary Ecology, Kiel, Germany
additional type: report

Time
type: DefinedTerm
alternate name: T

Length
type: DefinedTerm
alternate name: L

Pressure
type: DefinedTerm

water
type: DefinedTerm

Energy Density
type: DefinedTerm

Force Per Area
type: DefinedTerm

CTD
type: DefinedTerm

Temperature
type: DefinedTerm
alternate name: Θ

salinity
type: DefinedTerm

conductivity
type: DefinedTerm

oxygen
type: DefinedTerm
alternate name: O

Dimensionless Ratio
type: DefinedTerm
alternate name: ψ

data matrix.tab
type: FileObject
type: DataDownload
encoding format: text/tab-separated-values