ADMAP's Antarctic magnetic anomaly grids transformed for use with open source software

The Antarctic Digital Magnetic Anomaly Project (ADMAP) is an Expert Group of the Scientific Committee on Antarctic Research (SCAR). ADMAP compiles and publishes compilations of near surface magnetic anomaly data south of 60°S. Its two most recent compilations are referred to as ADMAP2B and ADMAP2S. ADMAP2B shows near-surface data only, with large gaps. ADMAP2S fills the gaps with satellite-derived data. Both products are freely available, but until now only for proprietary and/or custom software and with a custom map projection that is not widely used outside of the group. This contribution offers both ADMAP2B and ADMAP2S gridded data products in the widely used geotiff, netcdf, and kmz grid formats, and projected into the well known geodetic longitude-latitude and SCAR's recommended WGS-84 Antarctic Polar Stereographic system. These grids are suitable for use in a wide range of applications, including the widely-used free and open source products QGIS, Generic Mapping Tools, and Google Earth.