Ice station surface meteorology and radiation data from expedition ARTofMELT, Arctic Ocean, 2023

Heather Guy, Ian Brooks, Sonja Murto, Michail Karalis, Michael Tjernström

Measurements of near-surface meteorology, upwelling and downwelling radiative fluxes and snow temperature data were obtained from two installations (the Met Mast, and the radiometer stand) deployed on the sea ice near to the Swedish icebreaker Oden during the expedition ARTofMELT (Atmospheric Rivers and the Onset of Arctic Melt) in the Fram Strait pack ice during the spring transition, 8 May to 14 June of 2023. The installation was designed to fully characterise the surface energy budget on the sea-ice.

During ARTofMELT there were two Ice Stations: During Ice Station 1 measurements were collected on the sea ice continuously from 16 May to 22 May, and during Ice Station 2 measurements were collected on the sea ice continuously from 29 May to 12 June.

Data include air pressure, temperature, relative humidity, wind speed and direction, skin temperature, upwelling and downwelling long wave and shortwave radiation, sub-surface temperature at six depths between 0 and −0.64 m from the snow surface, and ice-to-snow heat flux at the snow-ice transition.

Citation

Heather Guy, Ian Brooks, Sonja Murto, Michail Karalis, Michael Tjernström (2024) Ice station surface meteorology and radiation data from expedition ARTofMELT, Arctic Ocean, 2023. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/oden-artofmelt-2023-surface-meteorology-ice-station-1

References

Guy H, Brooks I, Murto S, Karalis M, Tjernström M (2024) Ice station micrometeorological data from expedition ARTofMELT, Arctic Ocean, 2023. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/oden-artofmelt-2023-micrometeorology-ice-station-1

Data description

This dataset is provided in a zipped file containing 2 NetCDF (.nc) files, one file for each ice station. The zipped file also contains photographs of the instruments during each ice station, and the field log book (excel spreadsheet). The total file size is about 50 MB (compressed 45 MB).

Each NetCDF file contains 39 variables with dimensions of time and index. A detailed list of variables is included below.

Dimensions

• time Time (seconds since 1970-01-01 00:00:00)
• index Thermistor number, identifies the height of each thermistor relative to the snow surface, see variable height_relative_to_snow_surface

Variables

Detailed list:

• All variables
  • year Year
  • month Month
  • day Day
  • hour Hour
  • minute Minute
  • second Second
  • day_of_year time as decimal day of year
  • latitude Latitude, degree_north
  • longitude Longitude, degree_east
  • air_pressure Air Pressure, hPa
  • air_temperature Air Temperature, K
  • relative_humidity Relative Humidity, %
  • wind_speed Wind Speed, m s-1
  • wind_from_direction Wind From Direction, degree
  • downwelling_longwave_flux_in_air Downwelling Longwave Radiation, W m-2
  • downwelling_shortwave_flux_in_air Downwelling Shortwave Radiation, W m-2
  • downwelling_total_irradiance Downwelling Total Radiative Flux, W m-2
  • upwelling_longwave_flux_in_air Upwelling Longwave Radiation, W m-2
  • upwelling_shortwave_flux_in_air Upwelling Shortwave Radiation, W m-2
  • upwelling_total_irradiance Upwelling Total Radiative Flux, W m-2
  • net_total_irradiance Net Downwelling Radiative Flux, W m-2
  • ice_to_snow_heat_flux Ice to snow heat flux, W m-2
  • snow_temperature Snow Temperature, K
  • height_relative_to_snow_surface Height of thermistor relative to the snow surface (i.e. -ve is below snow surface), m
  • skin_temperature_1_raw Surface brightness temperature (9.6-11.5 μm) at the Met Mast (heated window), no bias correction applied, K
  • skin_temperature_1 Surface brightness temperature (9.6-11.5 μm) at the Met Mast (heated window) with bias correction applied, K
  • skin_temperature_2 Surface brightness temperature (9.6-11.5 μm) at the Radiometer Stand (unheated window), K
  • qc_flag_temperature Data Quality flag: Temperature
  • qc_flag_relative_humidity Data Quality flag: Relative Humidity
  • qc_flag_pressure Data Quality flag: Pressure
  • qc_flag_wind_speed Data Quality flag: Wind Speed
  • qc_flag_wind_from_direction Data Quality flag: Wind From Direction
  • qc_flag_downwelling_radiation Data Quality flag: Radiation
  • qc_flag_upwelling_radiation Data Quality flag: Radiation
  • qc_flag_ice_to_snow_heat_flux Data Quality flag: Ice to snow heat flux
  • qc_flag_snow_temperature Data Quality flag: Snow temperature
  • qc_flag_skin_temperature_1 Data Quality flag: Skin Temperature (Met Mast)
  • qc_flag_skin_temperature_2 Data Quality flag: Skin Temperature (Radiometer stand)

Comments

Measurement system

The measurement system consisted of two independent battery powered installations, the "Met Mast" and the "Radiometer Stand". The Radiometer Stand (all hemispheric radiometers and the KT15-2) was located approximately 40 m away from the Met Mast (all other instruments). Photographs of the measurement installations are included in the zipped datafile. GPS measurements on the Met Mast and the Radiometer Stand were used calculate a heading between the two installations allowing for the derivation of the true wind direction. Two Campbell Scientific CR1000 data loggers (one at the Met Mast and one at the Radiometer Stand) recorded data for the radiometers (Radiometer Stand) and the thermistor string and heat flux plate (Met Mast). The remaining data were logged by two Raspberry Pi's (one at the Met Mast and one at the Radiometer Stand).

Quality control

During the measurement period, the two installations were visited once per day when possible. During the visit, the data were downloaded, batteries were replaced, instrumentation were inspected, and any frost was removed from instrument windows. The daily visits were logged in the "icestation_logbook" which is included as an excel spreadsheet with this dataset.

Quality control flags for each variable are included in the data file. Note that poor quality data has not been removed, therefore it is essential to filter the data using the appropriate quality control flags before use.

The following additional factors should be considered when using this data:

• True wind directions are calculated using the heading between the two GPS units on the Met Mast and the radiometer stand.
• Vector wind averages are calculated before deriving the True wind direction in degrees.
• No tilt correction is applied to the 3D sonic anemometer data. Horizontal wind speed is calculated from all 3D components, assuming that the contribution of vertical velocity is negligible.
• Air pressure in this file is derived from the internal sensor in the Licor control box, no corrections have been applied.
• A bias correction has been applied to the Met mast KT15 (skin_temperature_1) based on the recorded temperature of melting snow. The instrument bias is due to the window heater that was activated on the Met mast KT15. Both raw (skin_temperature_1_raw) and corrected (skin_temperature_1) data are included in this dataset.
• The factory calibration is used for the heat-flux plate data.
• 1-minute averages are labelled for the LHS of the averaging window.

Associated raw data and code

The python code used to generate the NetCDF files and QC the raw data are available at GitHub.

The expedition

Data were collected during the ARTofMELT 2023 expedition on board the Swedish icebreaker Oden, which was organized by the Swedish Polar Research Secretariat from 8 May through 14 June, 2023.

Associated data from the expedition

See also thermodynamic and momentum flux estimations from the Ice station micrometeorological data from expedition ARTofMELT, Arctic Ocean, 2023 by Guy et al. (2024).

Data creators' roles

• Heather Guy (operator and dataset creator)
• Ian Brooks (operator and principal investigator)
• Sonja Murto (operator)
• Michail Karalis (operator)
• Michael Tjernström (chief scientist; operator)