Micrometeorological data from icebreaker Oden’s foremast during Ryder 2019 and Northwest passage 2019 expeditions
John Prytherch, Michael Tjernström
Air-sea fluxes and other micrometeorological variables derived from fast response (20 Hz) measurements of the 3-dimensional wind vector, temperature and humidity, and mean meteorological measurements using eddy covariance.
These are rare, direct measurements of the air sea exchange of momentum, sensible and latent heat from sea-ice regions of the Eastern Canadian Archipelago and Northern Greenland seas. They are key parameters in numerous processes, for example, determination of the surface energy balance.
The measurements are from instrumentation mounted on icebreaker Oden’s foremast at approximately 20 m above sea level during the Northwest Passage 2019, and Ryder 2019 expeditions in July, August and September 2019. Eddy covariance fluxes are determined on 30-minute intervals.
AtmosphereMicrometeorologyAir-sea interactionMeteorologyEddy covarianceArctic boundary layerGreenlandFjordNorthwest PassageRyder 2019 expeditionIcebreaker OdenACAS
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Citation
References
Jakobsson M, Mayer LA, Farrell F, Ryder 2019 Scientific Party (2020) Expedition report: SWEDARCTIC Ryder 2019, Swedish Polar Research Secretariat, 455 pp, ISBN 978-91-519-5132-4
Data description
Micrometeorology data from icebreaker Oden’s foremast, averaged over either 1 or 30-minute intervals. Flux data are not included in the 1-minute files. System operated by John Prytherch and Michael Tjernström (MISU). Two data formats are available: Matlab (.mat) and NetCDF (.nc) with an accompanying readme (.rtf) file.
Comments
The instrumentation on the foremast consisted of a Metek uSonic-3 heated sonic anemometer, a LI-COR 7500 infrared gas analyser, an aspirated TRH sensor, and an XSENS MTiG 3-axis inertial motion unit.
Wind measurements were corrected for platform motion following Edson et al. (1998; Direct covariance flux estimates from mobile platforms at sea. J. Atmos. Ocean. Tech, 15, 547-562) and Prytherch et al. (2015: Motion-correlated flow distortion and wave-induced biases in air-sea flux measurements from ships. Atmos. Chem. Phys., 15, 10619–10629).
Winds are measured relative to the ship. The ship acts to distort the wind speed and direction, increasingly so for winds away from bow-on. A computational fluid dynamics (CFD) model of airflow over Oden is used to correct the measured winds for wind directions within 150deg of bow on. An empirical adjustment to the model was derived from a comparison of the foremast wind measurements with those measured on the 15 m mast during the AO2018 ice camp.
The majority of the fast-response instrumentation measured at 20 Hz. Atmosphere-surface fluxes were determined from the fast-response measurements using eddy covariance. Metek anemometer winds have an aliasing correction applied prior to flux calculation, removing all signal above 5 Hz.
Quality control flagging follows Foken et al. (2012): Chapter 4 in Eddy Covariance: A practical guide to measurement and data analysis (eds. M. Aubinet, T. Vesala, D. Papale), Springer Atmospheric Sciences, and references therein: Foken and Wichura (1996) and Vickers and Mahrt (1997). Some of the code implementing these was adapted from the Eddycalc suite.
Data from the foremast are combined into a cruise-length file. The data are time-averaged to both 1-minute and 30-minute intervals. Flux data are not included in the 1-minute files.
Coordinates (lat, lon) for the observations are not included in this dataset, but they are the same as in the Weather data from MISU weather station during Ryder 2019 and Northwest passage 2019 expeditions.
Data were collected during the NorthWest Passage 2019 expedition and the Ryder 2019 expedition on board the Swedish icebreaker (I/B) Oden, which was organized by the Swedish Polar Research Secretariat.
Project
Ryder 2019. These data are part of the Arctic Climate Across Scales (ACAS) project, funded by the Knut and Alice Wallenberg Foundation. Project PI Michael Tjernström (MISU).
Publisher
Bolin Centre Database
License
First name
John
Last name or organisation
Prytherch
Email address
Address
Department of Meteorology (MISU); Stockholm University
Postal code
SE-106 91
City
Stockholm
Country
Sweden
GCMD science keyword
Earth science > Atmosphere
GCMD location
Continent > North America > Greenland
Dataset language
English
Begin date
2019-07-01
End date
2019-09-22