Methodology:

GNSS/INS buoy system was assembled by the University of Huddersfield. Each buoy system consists of a miniature inertial system (Spatial), a data storage (ILU), a GNSS antenna and a power supply. These sensor components were supplied from Advanced Navigation (advancednavigation.com) and Innovelec (innovelec.co.uk), and were then assembled in a weather-proof plastic case for deployment. A total of six sets of the GNSS/INS buoys were shipped to the expedition, but the number of the buoys deployed on the ice varied throughout the expedition due to the logistical and environmental circumstances. The deployment of the buoys was made in the vicinity (within 2 km) of RV Polarstern at the MOSAiC drifting site.

The buoys recorded the data from GNSS and Sensors. The raw GNSS data contain time, latitude, longitude, velocity, and fix type. The raw Sensors data contain time, acceleration, gyroscope, magnetometer, and temperature. These data were sampled at 10 Hz. The original data was in ANPP format (see advancednavigation.com), which have been converted to structured ASCII formats (such as RINEX, CSV) using Spatial Manager software.

Data collection:

Each GNSS sensor unit consists of Spatial, Data Interface Logging Unit (ILU), and antenna.

Spatial is a rugged miniature GPS aided inertial navigation system and AHRS that provides accurate position, velocity, acceleration and orientation. It combines temperature calibrated accelerometers, gyroscopes, magnetometers and a pressure sensor with advanced GNSS receiver to deliver accurate and reliable navigation and orientation (see advancednavigation.com/solutions/spatial/). The position accuracy can be a few centimetres as long as the antenna has a good sky view without any obstructions.

Data Interface Logging Unit (ILU) is a device server that interfaces to Spatial and provides data logging, a web interface, a time synchronisation server and different data input/output option.

Two types of GNSS antennas were used: Antcom (G5ANT-53A4T1) and Tallysman (TW3972).

Data quality:

This is a raw dataset, and no data quality check was applied to the data. The data at the start and end of the files may contain unrealistic values due to the disturbances caused by battery exchanges. The GNSS fix for the raw data should be 2 (3D fix with no base station data). Any data with Fix = 1 or 0 should be discarded from the analysis.