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In this paper, we present an electric-thermal drill with a novel design of a melting head that was developed within the EnEx-RANGE project. The design combines a short melting head with a large surface area of parabolic shape. It was succesfully tested in the laboratory as well as on Alpine glaciers (Langenferner and Mittelbergferner) and at the Ross Ice Shelf in Antarctica. In all these different environments, a high melting speed per specific power of typically 8.8 cm3 w-1 h-1 is achieved that is close to the ideal maximum bound of ~10.5-11.8 cm³ w-1 h-1 when neglecting all heat losses. It has also been demonstrated that the melting probe can be operated with typical equipment of small-scale field camps including a small power generator. [ABSTRACT FROM AUTHOR]

The IceCube Neutrino Observatory and its prototype, AMANDA, were built in South Pole ice, using powerful hot-water drills to cleanly bore >100 holes to depths up to 2500 m. The construction of these particle physics detectors provided a unique opportunity to examine the deep ice sheet using a variety of novel techniques. We made high-resolution particulate profiles with a laser dust logger in eight of the boreholes during detector commissioning between 2004 and 2010. The South Pole laser logs are among the most clearly resolved measurements of Antarctic dust strata during the last glacial period and can be used to reconstruct paleoclimate records in exceptional detail. Here we use manual and algorithmic matching to synthesize our South Pole measurements with ice-core and logging data from Dome C, East Antarctica. We derive impurity concentration, precision chronology, annual-layer thickness, local spatial variability, and identify several widespread volcanic ash depositions useful for dating. We also examine the interval around ∼74 ka recently isolated with radiometric dating to bracket the Toba (Sumatra) supereruption [ABSTRACT FROM AUTHOR]

The article presents a study which characterizes the glacial conditions at Halvfarryggen ice dome in Dronning Maud Land, Antarctica. It explores the potential drill site for the International Partnerships in Ice Core Sciences with specific atmospheric conditions, surface topography, and ice stratigraphy from radar data. It details the comprehensive approach in field data, remote sensing, and anisotropic ice-flow model in characterization of glacial conditions. The study suggests drilling into the apices of the deep anticlines for record length and temporal resolution.

The article reports on a study which discovered the active glaciological bodies sharing similar basal conditions for surface lakes. It refers to the unrelated subglacial lakes under the ice streams of Antartica and the supraglacial lakes observed in Iceland ice sheet. The Antarctic ice streams derive water from energy dissipation due to basal friction, while the Gleenland ice sheet derive water from atmospherically driven surface melting. It implies that glacial bodies can share common basal conditions and basal lakes can exist in tandem.

The article presents the first seasonal variations of 17O-excess and d-excess to offer an analogy with glacial climatic conditions in Vostok Station, Antarctica on an event basis over one year. It mentions that the 17O-excess and d-excess variations can be explained through the influence of low temperatures' kinetic fractionation. It states that the comparison with simple isotopic models affirms the explanation, but cannot explain the association between temperature, 17O-excess and d-excess without a particular relationship between surface temperature and condensation.

The question of how stable the climate in Antarctica has been during the last few million years compared to the rest of the planet is still controversial. This study attempts to add new information to the discussion by reconstructing the timing and spatial extent of glacial advances in northern Victoria Land over tens of thousands to millions of years. In Terra Nova Bay region, surface exposure ages and erosion rates of glacially rounded bedrock and glacial erratics have been determined using the cosmogenic nuclides ³He, [sup10]Be and [sup21]Ne. Three morphological units have been analysed. They yield minimum ages of 11 to 34 ka, 309 ka, and 2.6 Ma, respectively. Erosion rates were as low as 20 cm Ma[sup-1] since middle Pliocene time. Taking erosion into account, the oldest surface is 5.3 Ma old. Pleistocene glacier advances had considerable extent, reaching up to 780 m above modem ice levels, but have been restricted to the valleys since at least mid-Pliocene. The existence of landscapes of mid-Pliocene age in northern Victoria Land implies that the climatic stability of the McMurdo Dry Valleys is not unique within the Transantarctic Mountains, but rather the expression of a constantly cold and hyperarid climate regime in entire Victoria Land. [ABSTRACT FROM AUTHOR]