(S1) Grounding line and ice frontal positions for the Marie Byrd Land Sector of West Antarctica, 2003-2015, with links to shapefiles

1. This dataset contains shapefiles of the grounding lines (hereafter GLs) and ice frontal positions derived by Christie et al. (2018) for the Marie Byrd Land Sector of West Antarctica, 2003-2015.

2. Grounding lines were derived from a combination of Landsat 7 Enhanced Thematic Mapper, Landsat 8 Operational Land Imager and Terra-ASTER Level 1 Terrain Corrected optical satellite imagery (see Christie et al., 2018; their Figure S1), and represent the inflexion point of the ice-sheet-shelf grounding zone, otherwise known as 'Point Ib' (following the notation of Fricker et al., 2009, doi:10.1017/S095410200999023X). Acting as a reliable proxy for the true GL, G, which cannot be detected directly from satellite imagery, Point Ib typically resides ~1-2 km downstream of the G throughout most of the Marie Byrd Land Sector. For more information on GL detection techniques and the anatomy of the grounding zone, users are referred to Fricker et al. (2009, doi:10.1017/S095410200999023X), Brunt et al. (2010, doi:10.3189/172756410791392790), Bindschadler et al. (2011, doi:10.5194/tcd-5-183-2011), Rignot et al. (2011, doi:10.1029/2011GL047109) and Christie et al. (2016, doi:10.1002/2016GL068972). […]