4a6096e7-6350-416d-a2a1-6a24adaaf929 eng utf8 dataset dataset NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom polardatacentre@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact 2021-11-11 ISO 19115 Geographic Information - Metadata ISO 19115:2003(E) European Petroleum Survey Group (EPSG) Geodetic Parameter Registry 2008-11-12 publication European Petroleum Survey Group EPSGadministrator@iogp.org https://www.epsg-registry.org/ EPSG Geodetic Parameter Dataset The EPSG Geodetic Parameter Dataset is a structured dataset of Coordinate Reference Systems and Coordinate Transformations, accessible through this online registry. information publisher urn:ogc:def:crs:EPSG::3031 6.18.3 Processed line aeromagnetic data from the 2015/16 PolarGAP survey of the South Pole region. 2021-11-11 creation 2021-11-11 revision 2021-11-11 publication 2021-11-11 released 1 https://doi.org/10.5285/4a6096e7-6350-416d-a2a1-6a24adaaf929 doi GB/NERC/BAS/PDC/01584 https://data.bas.ac.uk/ Please cite this item as: None The ESA PolarGap airborne gravity, lidar/radar and aeromagnetic survey was carried out in Antarctica in the field season 2015/16. The purpose of the 2015/16 ESA PolarGAP airborne survey of the South Pole region was to fill the gap in satellite gravity coverage, enabling construction of accurate global geoid models. Additional radar flights over the Recovery Lakes for the Norwegian Polar Institute (NPI) were carried out as part of the same survey. In conjunction with the primary datasets aeromagnetic data was collected opportunistically, to provide new insights into the subglacial geology. Data were collected using a caesium magnetometer system, and have been corrected to total field values following the approach laid out by the SCAR ADMAP working group (http://admap.kopri.re.kr/ADMAP-2_SCR_27Aug13.pdf). The aircraft used was the BAS aerogeophysicaly equipped twin otter VP-FBL. Data are available as an ASCII table (.csv). No credit. completed Jordan, Tom British Antarctic Survey Researcher author Robinson, Carl British Antarctic Survey Researcher author Matsuoka, Kenichi Norvegian Polar Institute Researcher author Olesen, Arne Technical University of Denmark Researcher author Forsberg, Rene Technical University of Denmark Researcher author Ferraccioli, Fausto British Antarctic Survey Researcher author NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact asNeeded completed EARTH SCIENCE > Solid Earth > Geomagnetism > Magnetic Anomalies theme Global Change Master Directory (GCMD) Science Keywords 2026-01-27 publication 23 Global Change Data Center, Science and Exploration Directorate, Goddard Space Flight Center (GSFC) National Aeronautics and Space Administration (NASA) Greenbelt MD United States of America https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords Global Change Master Directory (GCMD) Keywords The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. information publisher Aerogeophysics Aeromagnetics Antarctica Magnetics South Pole geophysics theme South Pole Antarctica Recovery Lakes Antarctica Thiel Mountains Antarctica place Geology theme GEMET - INSPIRE themes, version 1.0 2021-01-06 revision otherRestrictions no limitations to public access otherRestrictions no limitations license Open Government Licence v3.0 otherRestrictions This data is governed by the NERC Data Policy: https://www.ukri.org/who-we-are/nerc/our-policies-and-standards/nerc-data-policy/ otherRestrictions Further by downloading this data the user acknowledges that they agree with the NERC data policy (), and the following conditions: 1. To cite the data in any publication as follows: https://doi.org/10.5270/esa-8ffoo3e - PolarGap: "Filling the GOCE polar gap in Antarctica and ASIRAS flight around South Pole" 2. The user recognizes the limitations of data. Use of the data is at the users' own risk, and there is no warranty as to the quality or accuracy of any data, or the fitness of the data for your intended use. The data are not necessarily fully quality assured and cannot be expected to be free from measurement uncertainty, systematic biases, or errors of interpretation or analysis, and may include inaccuracies in error margins quoted with the data. otherRestrictions None doi doi crossReference url url crossReference textTable eng utf8 geoscientificInformation -180.0 180.0 -90.0 -80.4 2015-12-15 2016-01-20 It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk. NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information distributor bytes 1 https://ramadda.data.bas.ac.uk/repository/entry/show?entryid=4a6096e7-6350-416d-a2a1-6a24adaaf929 WWW:LINK-1.0-http--link Get Data Download data download dataset Methodology: The raw aeromagnetic data was initially corrected for DC offsets due to aircraft procedures, such as pumping fuel from so called 'tip tanks'. Most of these corrections were in turns, but logistical considerations meant such corrections on lines were unavoidable. Due to the unusual radial survey design normal compensation for aircraft dynamics was not possible. However, visual comparison between recorded fluxgate and total field data on the aircraft suggested most dynamic noise had a frequency of <15 seconds (~900m). The tip corrected data was therefore filtered with a 15 second low pass filter to remove dynamic noise prior to decimation from 10Hz to 1Hz to enhance the efficiency of data processing. The total field magnetic data was corrected for the core field using the 2015 IGRF, implemented in the Geosoft software package. The base-station correction for diurnal variations was derived from multiple base-station observations. Base station data at the PolarGAP field camps (Thiel Mountains and FD83) was collected using total-field sensors, with additional fluxgate magnetometer data from the Polar Experiment Network for Geospace Upper atmosphere Investigations (PENGUIn) at South Pole and other remote field sites. All base station data was converted into total field values, and each station corrected to have a zero mean across the survey period. The theoretical base station value at the aircraft was calculated using an inverse distance weighting scheme to merge base station observations (Shenwary et al 2011). This incorporates the base station corrections from all available base stations weighted by their distance to the survey aircraft. This technique provided a smooth transition between different base stations, and ensures the most 'local' base station dominates the correction. As short wavelength diurnal variations observed at a base station are often not fully representative of those occurring at large distances from the base station, the base station corrections were filtered with either a 60 or 30 minute low-pass filter. The base station data is also provided for reference. After base station correction preliminary levelling of the 30 minute base station corrected magnetic data was carried out. This included minimising internal crossovers and discrepancies with other surveys in the region. In general the preferred levelling method removed a 0, or 1st order trend revealed by errors at a number of intersections. Where residual line to line discrepancies remained, more complex spline levelling was applied. Further improvement of the dataset by more detailed levelling may be possible. The aeromagnetic data set includes the following channels: Line: Sequential survey flight number from P03 to P39: decimals denote line breaks. Lon: Longitude DDD.DDDDDDDD Lat: Latitude DD.DDDDDDDD Elev: Elevation on the WGS1984 ellipsoid Date: Date YYYY/MM/DD Time: Time (UTC) HH:MM:SS.SS MagR: Raw total field magnetic data (nT) MagC: Pseudo-compensated total field magnetic data (nT) TCorr: Tip correction (nT) RefField: IGRF correction (nT) MagRTC: Mag after IGRF: compensation and tip correction (nT) Bcorr_60min: IDW base station correction with 60 minute mean filter (nT) Bcorr_30min: IDW base station correction with 30 minute mean filter (nT) MagB60RTC: Final mag after 60 min base station correction (nT) MagB30RTC: Final mag after 30 min base station correction (nT) MagL_B30RTC: Magnetic anomaly after preliminary levelling (nT) The magnetic base station data set includes the following channels: Line: PolarGAP flight number TimeUTC: Time UTC (HH:MM:SS.SS) UTCDate: Date (YYYY/MM/DD) Longitude_decimal_degrees: Survey aircraft longitude (DDD.DDDDDDDDD) Latitude_decimal_degrees: Survey aircraft Latitude (DD.DDDDDDDDD) x: Polar stereographic projected aircraft x position (true scale -71) (m) y: Polar stereographic projected airc...(23) Data collection: Data was collected using the BAS aerogeophysicaly equipped twin otter VP-FBL. Magnetic data was collected using wing tip mounted Scintrex CS-3 High Sensitivity Cs magnetometers. Only data from the magnetometer with the lowest noise characteristics is reported here. Data was recorded at 10 Hz on a PicoEnvirotec logging system. Additional base station information from total-field magnitomiters at field camps and fluxgate magnitomiters from the Polar Experiment Network for Geospace Upper atmosphere Investigations (PENGUIn) network were used. Data quality: After the basic processing presented here the standard deviation of the crossover errors was 52 nT, after preliminary levelling the crossover error was 25 nT. Data resolution: The radial design of the survey makes defining a specific resolution problematic. Line spacing at the survey edges was 90 km, reducing towards South Pole. The provided data is sampled at 1Hz, along track which equates to a ~60m along track sample spacing. The true usable resolution of this dataset is proportional to the depth to source, which averages to 2900 m across the survey. asNeeded completed