Michael Tjernström, Sonja Murto, Michail Karalis, John Prytherch
Estimates of vertically integrated water-vapor and liquid-water paths are obtained from measurements with a HATPRO5 passive microwave radiometer deployed on 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, 7 May to 14 June of 2023.
The radiometer was installed on the roof of a 4th deck container, at about 20 m above sea level, located on the forward starboard side of Oden's superstructure. Measurements ran continuously during the whole expedition.
An associated dataset, containing the raw data, is available separately. The current dataset is simply the concatenation of the original raw files.
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Citation
Michael Tjernström, Sonja Murto, Michail Karalis, John Prytherch (2024) Integrated column water vapor and liquid water paths from expedition ARTofMELT, Arctic Ocean, 2023. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/oden-artofmelt-2023-microwave-column-water-1
References
Tjernström T, Murto S, Karalis M, Prytherch P (2024) Integrated column water vapor and liquid water paths from expedition ARTofMELT, Arctic Ocean, 2023 — raw data. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/oden-artofmelt-2023-microwave-column-water-raw-1
Data description
This dataset includes one NetCDF (.nc) file with the time series of vertically integrated water-vapor path, sometimes also known as precipitable water, and vertically integrated liquid-water path, derived from the passive microwave radiometer irradiances. The file size is 132 MB (compressed 32 MB).
A list of variable names, with short explanations and units is provided below. There is also an associated Readme_HATPRO.txt file that provides definitions.
Variables
Primary variables are the water-vapor and liquid-water paths.
- Primary variables
day_of_year Decimal day of year (in UTC) [time]year Year - constant [time]month Month of the year [time]day Day of the month [time]hour Hour of the day (in UTC) [time]minute Minutes of the hour [time]second Seconds of the minute [time]integrated_water_vapor Integrated water vapor [kg m⁻²]liquid_water_path Liquid water path [g m⁻²]flag_for_rain Data flag for rain; related to liquid water path. 0 = no rain, 1 = raining
Comments
Measurement system
The data was obtained from a Radiometer Physics microwave radiometer (HATPRO5) that passively measures the atmospheric irradiance at a number of microwave frequencies.
Quality control
No general data quality control is applied, except for removing a very few data points (set to NaN) around 11 UTC on 2 June when a crane was maneuvered above the sensor. The water vapor measurements are insensitive to the presence clouds, however, the liquid water path measurement is sensitive to water droplets or snow on the surface of the instrument. A fan blows heated air across its surface to remove droplets or snow; a rain sensor indicates if rain was present.
Associated raw data
The raw data, from which this dataset is derived, was created by Tjernström et al. (2024) and is available separately. The current dataset is simply the concatenation of the original raw files on the native time scale and no code is available for that processing.
Data creators' roles
The instrument system was continuously logging and was monitored by the Stockholm University Meteorology team onboard Oden:
- Michael Tjernström (chief scientist; operator and dataset creator)
- Sonja Murto (operator)
- Michail Karalis (operator)
John Prytherch (also Stockholm University) is responsible for the instrument system.
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.