Baltic Sea 2023 R/V Skagerak Cruise Data (CTD Stations; Radium; DSi)

Data were collected across the Baltic Sea in surface water and the bottom water column in September 2023.

Dataset consists of four files: 

(1) Baltic2023_Samples_Data_V2.csv (Sample Data) 

Column Names and Description:

Sample_ID: Sample name, with the following scheme, BS_STN_DEP where STN is the three-digit station number and DEP is the depth above the seafloor in meters.

Station: Station number

Type: SURF (collected from surface water, ~4 m depth), CTD (collected from bottom waters via CTD rosette)

Lat: Latitude of station.

Long: Longitude of station.

Datetime_UTC: Date and time of sampling in UTC.

Depth_m: Sample depth (m). Measured with Sea-Bird SBE 911.

dist_along_track_km: Distance along cruise track (km).

Salinity: Water column salinity. Measured with Sea-Bird SBE 911.

Temp_C: Water column temperature (°C). Measured with Sea-Bird SBE 911.

DO_per: Dissolved oxygen in %. Measured with Sea-Bird SBE 911.

Rho_kg_m3: Water column density (kg/m^3), calculated from CTD data using the the Thermodynamic Equation of Seawater 2010 (TEOS-10) equation of state and the Gibbs Seawater (GSW) Oceanographic Toolbox in Python (McDougall and Barker, 2011).

Ra224_dpm_100L: 224Ra concentration in dpm/100 L. Measured with a RaDeCC system.

Ra224_dpm_100L_unc: 224Ra concentration analytical uncertainty in dpm/100 L via error propogation.

DSi_umol_L: Dissolved silicate concentration in µmol/L. Measured with a SEAL AA500 AutoAnalyzer.

(2) Baltic2023_CTD_data_V2.csv (CTD Data) 

Processed and cleaned CTD profiles for all stations.

Column Names and Description:

Station: Station number

Pressure_dbar: Pressure in decibars. Measured with Sea-Bird SBE 911.

Temperature_C: Water column temperature (°C). Measured with Sea-Bird SBE 911.

Depth_m: Sample depth (m). Measured with Sea-Bird SBE 911.

Salinity: Water column salinity. Measured with Sea-Bird SBE 911.

DO_per: Dissolved oxygen in %. Measured with Sea-Bird SBE 911.

Lat: Latitude of station.

Long: Longitude of station.

Rho_kg_m3: Water column density (kg/m^3), calculated from CTD data using the the Thermodynamic Equation of Seawater 2010 (TEOS-10) equation of state and the Gibbs Seawater (GSW) Oceanographic Toolbox in Python (McDougall and Barker, 2011).

(3) Baltic2023_Raeff_data_V2.csv (Radium efficiency Data)

Data required to compute radium efficiency. For more info, please see accompanying manuscript. _UP refers to the first/most upstream/first MnO2 fiber and _DOWN refers to the last/most downstream/second MnO2 fiber aligned in a series. 

Column Names and Description:

Sample: Sample name.

TOT_CNTS_dpm_UP: Total counts in dpm in UP fiber. Measured with a RaDeCC system.

TOT_CNTS_dpm_DOWN: Total counts in dpm in DOWN fiber. Measured with a RaDeCC system.

Ra224_dpm_100L_UP: 224Ra concentration in dpm/100 L in UP fiber. Measured with a RaDeCC system.

Ra224_dpm_100L_UP_unc: 224Ra concentration uncertainty in dpm/100 L in UP fiber.

Ra224_dpm_100L_DOWN:  224Ra concentration in dpm/100 L in DOWN fiber. Measured with a RaDeCC system.

Ra224_dpm_100L_DOWN_unc: 224Ra concentration uncertainty in dpm/100 L in DOWN fiber.

(4) Baltic2023_radecc_data_V2.csv (Raw RaDeCC Data)

Data measured by the RaDeCC and other underlying data required for radium calculations. 

Column Names and Description:

Sample: Sample name.

Coll_date_CEST: Date of sample collection in CEST. Format: YYYY-MM-DD.

Coll_time_CEST: Time of sample collection in CEST. Format: 24:MM:SS.   

Vol_L: Sample water volume passed through the MnO2 coated fiber (L).   

Bkg_cpm: Total background counts in counts per minute measured on the RaDeCC prior to analysis.

Count_date_CEST: Date sample run started on RaDeCC in CEST. Format: YYYY-MM-DD.

Count_time_CEST: Time sample run started on RaDeCC in CEST. Format: 24:MM:SS. 

Count_min: Duration of sample counting time on the RaDeCC in minutes.   

219_cpm: Counts per minute in the 219 channel on the RaDeCC.    

220_cpm: Counts per minute in the 220 channel on the RaDeCC.       

Total_cpm: Counts per minute in the total channel on the RaDeCC.         

exRa224_dpm_100L: Final sample 224Ra concentration in dpm/100 L. Measured with a RaDeCC system.    

exRa224_unc_dpm_100L: Final 224Ra concentration uncertainty in dpm/100 L.