AAS_4506_Buoys_Casey_2021_2022_2024
This dataset contains observations by wave-ice buoys made under the Australian Antarctic Program, Project 4506. Deployments were done in 2021, 2022, and 2024. Buoys were initially deployed on landfast sea ice, near Casey Station (66.2 degrees South, 110.63 degrees East). Data includes buoy longitude/latitude coordinates and measured wave spectrum.
Data 2021:
Four wave-ice buoys were deployed on the 10th of September on landfast sea ice. Due to rapidly changing sea ice conditions, three buoys (Rabault et al., 2020; https://doi.org/10.1016/j.coldregions.2019.102955) were deployed parallel to the coast, and the fourth buoy perpendicular to the coast. Two of these buoys included a wind anemometer providing observations of mean wind speed at a height of 90 cm above the surface (6410 Anemometer - Davis Instruments). The sea ice thickness at the time of deployment was between 120--130 cm with snow thickness between 12--20 cm. One buoy broke out at the start of October and the last signal transmitted by this buoy was on the 17th of November 2021.
Data 2022:
The second experiment started on the 25th of August 2022 with four OpenMetBuoys (OMBs) (Rabault et al., 2022; https://doi.org/10.3390/geosciences12030110) deployed on landfast sea ice. The OMBs were deployed along a transect roughly perpendicular to the fast sea ice edge. The sea ice thickness was measured during the deployment at 65--76 cm. Data transmission from three buoys was lost within two weeks of the deployment date. During a site revisit, the located buoys were found to have been covered by 30 cm of snow which was expected to be the cause of transmission loss. One of the buoys broke out starting on the 12th of October. Last transmission occurred on the 8th of January 2023, which is close to the expected depletion date of the battery.
Data 2024:
Instruments were deployed on landfast sea ice on the 3rd of October 2024, comprising of three OMBs, deployed along a transect perpendicular to the local fast sea ice edge. Sea ice and snow thickness was measured at the time of deployment and was 55 and 14 cm, respectively, for the two buoys closest to the fast sea ice edge, whereas the buoy closest to the coast was on sea ice and snow of thickness 92 and 30 cm, respectively. After one week, the buoy closest to the coast stopped transmitting due to unknown reasons. The sea ice surrounding the other two buoys started to breakup on the 19th of November leading to breakout of two buoys. The second buoy stopped transmitting on the 27th of November and was at that time only 9.6 km separated from the first buoy. The cause of failure is unknown, but it is noteworthy that also the first buoy stopped transmitting around the same time for two days before reconnecting. We therefore suspect snowfall to be the cause. The first buoy continued to drift westward and the last transmission was received on the 13th of January 2025.
