The 3–D current velocity 5-m beneath landfast ice in Prydz Bay, East Antarctica, recorded from an Acoustic Doppler Velocimeter (ADV) from April to November 2021

The data recorded field observations of 3–D current velocity beneath landfast ice outside Zhongshan Station in Prize Bay, East Antarctica. From April 16 to November 7, 2021, an observation station was established by the wintering team at the coastal landfast ice site, about 1 km off Zhongshan Station (69°22′ S, 76°22′ E). A set of Acoustic Doppler Velocimeters (ADV) was deployed to observe the ocean 3–D velocity (the meridional (U), zonal (V), and vertical direction (W)), at 5 m below the ice surface and 60 m north from shore. The frequency for ocean velocity observations was 40 s, and the accuracy was ±0.001 m s-1. To mitigate the error of high-frequency observations, data were sampled with the sliding mean to a 2-minute interval. Due to the insufficient power of the instrument, the data recording was briefly missing from April 23 to May 12 and from August 24 to August 25. The 2-minute frequency records of U and V showed a large oscillation, mainly varied among ±20 cm s-1. W showed a relatively small oscillation, mainly varied between ±4 cm s-1 and 98% of W were among ±2 cm s-1. The typical periods for U, V, and W were all half-day. The results showed that the 3–D current velocity recorded data has good quality and can be used as a basic data set for sea ice thermodynamic and dynamics analysis and remote sensing verification.The data is recorded in text format (.txt). The fields include time, meridional velocity, zonal velocity, and vertical velocity.