Near seafloor CTD-profiles, oxygen time series, and water velocity profile time series at the station Askö B1, Sweden, June 2019

Jonas Fredriksson, Volker Brüchert

The dataset consists of 3 sets of total 613 benthic profiles with a conductivity-temperature-depth (CTD) sonde positioned at the seafloor in the benthic boundary layer (BBL). The profiles were collected at a water depth of 40 m. The dataset contains oxygen concentrations, temperature, salinity and turbidity profiles in 1 – 50 cm above the seafloor, 3 series of oxygen concentration time series measured at 6 and 27 cm above the seafloor and 3 water velocity profiles time series collected with a down looking acoustic doppler current profiler (ADCP) covering the interval ~3 – 50 cm above the seafloor. In addition to the benthic data, the dataset contains 3 full water column CTD casts collected within an hour of the start of the 3 time-series and a full water ADCP dataset.

The data was collected in order to assess oxygen dynamics in the BBL (lateral transport, vertical mixing, sediment oxygen demand, resuspension of sediments and the connection between resuspension and changed sediment oxygen demand).

The data was collected in June 2019, approximately 200 m from the measuring station Askö B1, Trosa archipelago, Sweden. Water column profiling was conducted by CTD and shipborne ADCP. Two benthic lander systems collected data in situ at 40 m depth continuously for several days at a time.

Citation

Jonas Fredriksson, Volker Brüchert (2024) Near seafloor CTD-profiles, oxygen time series, and water velocity profile time series at the station Askö B1, Sweden, June 2019. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/fredriksson-2024-asko-bbl-2019-1

References

Fredriksson JP, Attard K, Stranne C, Koszalka IM, Glud RN, Andersen TJ, Humborg C, Brüchert V (2024) Hidden seafloor hypoxia in coastal waters. Limnology and Oceanography. https://doi.org/10.1002/lno.12607

Data description

The dataset consists of a folder fredriksson-2024-asko-bbl-2019-1.zip with the following directories:

1. BBL_ADCP 3 .csv files containing temperature and near seafloor flow velocity and direction and a ReadMe.txt

   1. benthic_ADCP_june10.csv
   2. benthic_ADCP_june14.csv
   3. benthic_ADCP_june19.csv

2. CTD 12 .csv files containing oxygen, salinity, temperature and turbidity measurements and a ReadMe.txt

   1. oxygen-1.csv Dissolved oxygen (mg/L)
   2. oxygen-2.csv
   3. oxygen-3.csv
   4. salinity-1.csv Absolute salinity (g/Kg)
   5. salinity-2.csv
   6. salinity-3.csv
   7. temperature-1.csv Conservative temperature (°C)
   8. temperature-2.csv
   9. temperature-3.csv
   10. turbidity-1.csv Turbidity (FTU)
   11. turbidity-2.csv
   12. turbidity-3.csv

3. CTD ship 3 .csv files containing depth, oxygen concentration, absolute salinity, conservative temperature, and turbidity and a ReadMe.txt

   1. wc_CTD-1.csv
   2. wc_CTD-2.csv
   3. wc_CTD-3.csv

4. Oxygen_optode 3 .csv files containing oxygen and temperature measurements and a ReadMe.txt

   1. Aanderaa_20190610.csv
   2. Aanderaa_20190614.csv
   3. Aandera_20190619.csv

5. ship_ADCP 6 .asc files containing full water column flow velocity and direction and a ReadMe.txt

   1. v_vel.asc
   2. u_vel.asc
   3. time.asc
   4. speed.asc
   5. direction.asc
   6. depth.asc

Comments

Coordinates: 58° 48' 07.0800'' N, 17° 37' 30.4200'' E