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Abstract A dataset to describe exposed bedrock and surficial geology of Antarctica has been constructed by the GeoMAP Action Group of the Scientific Committee on Antarctic Research (SCAR) and GNS Science. Our group captured existing geological map data into a geographic information system (GIS), refined its spatial reliability, harmonised classification, and improved representation of glacial sequences and geomorphology, thereby creating a comprehensive and coherent representation of Antarctic geology. A total of 99,080 polygons were unified for depicting geology at 1:250,000 scale, but locally there are some areas with higher spatial resolution. Geological unit definition is based on a mixed chronostratigraphic- and lithostratigraphic-based classification. Description of rock and moraine polygons employs the international Geoscience Markup Language (GeoSciML) data protocols to provide attribute-rich and queryable information, including bibliographic links to 589 source maps and scientific literature. GeoMAP is the first detailed geological map dataset covering all of Antarctica. It depicts ‘known geology’ of rock exposures rather than ‘interpreted’ sub-ice features and is suitable for continent-wide perspectives and cross-discipline interrogation. 

Abstract We investigate the spatial distribution, spectral properties and temporal variability of primary producers (e.g. communities of microbial mats and mosses) throughout the Fryxell basin of Taylor Valley, Antarctica, using high-resolution multispectral remote-sensing data. Our results suggest that photosynthetic communities can be readily detected throughout the Fryxell basin based on their unique near-infrared spectral signatures. Observed intra- and inter-annual variability in spectral signatures are consistent with short-term variations in mat distribution, hydration and photosynthetic activity. Spectral unmixing is also implemented in order to estimate mat abundance, with the most densely vegetated regions observed from orbit correlating spatially with some of the most productive regions of the Fryxell basin. Our work establishes remote sensing as a valuable tool in the study of these ecological communities in the McMurdo Dry Valleys and demonstrates how future scientific investigations and the management of specially protected areas could benefit from these tools and techniques. 

Abstract. The Reference Elevation Model of Antarctica (REMA) is thefirst continental-scale digital elevation model (DEM) at a resolution ofless than 10 m. REMA is created from stereophotogrammetry with submeterresolution optical, commercial satellite imagery. The higher spatial andradiometric resolutions of this imagery enable high-quality surfaceextraction over the low-contrast ice sheet surface. The DEMs are registeredto satellite radar and laser altimetry and are mosaicked to provide acontinuous surface covering nearly 95 % the entire continent. The mosaicincludes an error estimate and a time stamp, enabling change measurement.Typical elevation errors are less than 1 m, as validated by thecomparison to airborne laser altimetry. REMA provides a powerful newresource for Antarctic science and provides a proof of concept forgenerating accurate high-resolution repeat topography at continentalscales.