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Changes in sea ice conditions and atmospheric circulation over the Southern Ocean play an important role in modulating Antarctic climate. However, observations of both sea ice and wind conditions are limited in Antarctica and the Southern Ocean, both temporally and spatially, prior to the satellite era (1970 onwards). Ice core chemistry data can be used to reconstruct changes over annual, decadal, and millennial timescales. To facilitate sea ice and wind reconstructions, the CLIVASH2k (CLimate Variability in Antarctica and the Southern Hemisphere over the past 2000 years) working group has compiled a database of two species, sodium [Na+] and sulfate [SO42-], commonly measured ionic species. The database (https://doi.org/10.5285/9E0ED16E-F2AB-4372-8DF3-FDE7E388C9A7; Thomas et al., 2022) comprises records from 105 Antarctic ice cores, containing records with a maximum age duration of 2000 years. An initial filter has been applied, based on evaluation against sea ice concentration, geopotential height (500 hPa), and surface wind fields to identify sites suitable for reconstructing past sea ice conditions, wind strength, or atmospheric circulation.

Este estudo consiste na análise morfométrica da Península Keller, ilha Rei George, arquipélago das Shetlands do Sul, Antártica, usando técnicas de Sistema de Informação Geográfica (SIG). Uma fotografia aérea vertical e o Modelo Digital do Terreno (MDT) usados na elaboração de um mapa topográfico da PK na escala 1:5.000 foram processados em estação fotogramétrica digital para gerar uma ortofoto e uma ortofotocarta. O referido MDT, os pontos cotados e curvas de nível desse mapa topográfico foram armazenados em um SIG. Um MDT mais detalhado foi gerado para a área de entorno da Estação Comandante Ferraz (EACF), pela adição de pontos cotados da planta topográfica dessa estação. A partir desses MDTs foram derivados mapas hipsométricos, de declividade e aspecto, modelos de sombreamento analítico, cenas perspectivas tridimensionais e perfis topográficos, assim como medidas de distâncias, perímetros, áreas e volumes. Com base nos dados do MDT resultante deste estudo, a elevação média da PK é 96,5 m e a máxima de 332,8 m (monte Birkenmajer). Na PK predominam terrenos com declividade forte ondulada (35,6%), seguida pelas classes montanhosa (22,3%), ondulada (20%) e escarpada (12,8%). As vertentes da PK são principalmente orientadas para oeste (21,3%) e leste (15,3%). This study consists in the morphometric analysis of Keller Peninsula (KP), South Shetland Archipelago, Antarctica, using Geographical Information System (GIS) techniques. We processed a vertical metric aerial photography and a Digital Terrain Model (DTM) used in the compilation of the KP topographic map at a scale of 1:5,000, in a Digital Photogrammetric Station, to generate an orthophoto and then to create an orthophotomap. This DTM, altimetric points and contour lines from this topographic map were stored in the GIS. A more detailed DTM for the area surrounding the Brazilian Comandante Ferraz Station (EACF) were generated adding altimetric points from an EACF topographic plan. From these DTMs, we derived hypsometric, slope and aspect maps, hillshade models, perspective view scenes and topographic profiles, as well as measurements of distances, perimeters, areas and volumes for the KP and the EACF areas. Based on the DTM of this study, the mean KP elevation is 96.5 m and the maximum one is 332.8 m (Birkenmajer Mount). At KP predominates steep terrain slopes (35.6%), followed by very steep (22.3%), moderate (20%) and abrupt areas (12.8%). Its hillsides are mainly westward (21.3%) and eastward (15.3%) oriented.