Processed line aeromagnetic data over the Thwaites glacier region (2019/2020 season)

Raw line aeromagnetic data from the December 2019 ITGC airborne survey were initially corrected for the regional geomagnetic field (IGRF), and compensated for aircraft motion. Compensation coefficients were calculated from a calibration flight flown ~500m above the Lower Thwaites Glacier field camp during the previous season, and are therefore not optimal. The dataset may benefit from a low pass filter to remove residual noise due to aircraft dynamic motion. Diurnal variations in the magnetic field were recorded at 30 second intervals using a base station at Lower Thwaites Glacier field camp. Base station corrections were calculated by subtracting the local mean base station value across the survey from the recorded base station values. The base station corrections were then filtered with a 30 minute filter to ensure short wavelength signals, likely only seen at the base station, were not transferred to the airborne dataset. No base correction was applied to any of the transits, or initial calibration flights. An additional Tip Tank correction was made to remove the offsets induced by aircraft operational procedures such as pumping fuel. This correction is generally restricted to turns and transits, as data quality is worse during these times, and users may wish to consider discarding this data. DATA FORMAT: Data are provided in ASCII file format (.csv). The data set includes the following channels: FlightID: Sequential survey flight number from T1 to T17. x: coordinate (m) Polar stereographic true scale -71 y: coordinate (m) Polar stereographic true scale -71 Lon: Longitude DDD.DDDDDDDD Lat: Latitude DD.DDDDDDDD Height_WGS1984: Elevation on the WGS1984 ellipsoid (m) Date: Date YYYY/MM/DD Time: Time (GPS) HH:MM:SS.SSSSS MagR: Raw total field magnetic data (nT) MagC: Compensated total field magnetic data (nT) RefField: IGRF correction (nT) TCorr:Tip correction (nT) MagRTC: Mag after IGRF, compensation and tip correction (nT) Bcorr: Base station correction with 30 minute mean filter (nT) MagBRTC: Mag after all corrections (nT)