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Antarctic firn presents an exotic seismological environment in which the behaviors of propagating waves can be significantly at odds with those in other Earth media. We present a condensed view of the nascent field of ambient noise seismology in Antarctic firn-covered media, and highlight multiple unusual and information-rich observations framed through the lens of the firn's important role as a buffer for air temperature anomalies and a complex contributor to ice mass balance. We summarize key results from several recent papers depicting novel wind-excited firn resonances and point to the plethora of ways these observations could facilitate imaging and monitoring of glacial systems at single, isolated seismometers. Finally, we propose significant instrumental and computational objectives necessary to constrain resonance excitation mechanisms and broadly apply these observations as useful monitoring tools in Antarctica. [ABSTRACT FROM AUTHOR]

This paper reports geochemical characteristics of mafic gneisses and granulites collected from four localities in central Dronning Maud Land to evaluate the tectonic setting of their precursor rocks. Precursor rocks for the mafic gneisses and granulites in central Dronning Maud Land were formed in different geological backgrounds and tectonic settings. The mafic gneisses and granulites in the Schirmacher Hills were derived from basaltic rocks in a back-arc setting. Published U–Pb zircon ages and the geochemical variation of the basement rocks indicate their emplacement between 800 and 650 Ma, close to peak metamorphism. While similar protoliths were recognized in the inland nunataks of Hochlinfjellet, in Filchnerfjella the mafic gneisses/granulites were derived from basaltic rocks formed in marginal continental arcs or island arcs. Highly disturbed trace-element patterns indicate that the metamorphic process influenced the geochemical composition during the prograde metamorphic stage. Our results imply that the outcrops in central Dronning Maud Land with different metamorphic ages contain mafic gneisses/granulites from precursor rocks formed under different tectonic settings. [ABSTRACT FROM AUTHOR]

Antarctic firn presents an exotic seismological environment in which the behaviors of propagating waves can be significantly at odds with those in other Earth media. We present a condensed view of the nascent field of ambient noise seismology in Antarctic firn-covered media, and highlight multiple unusual and information-rich observations framed through the lens of the firn's important role as a buffer for air temperature anomalies and a complex contributor to ice mass balance. We summarize key results from several recent papers depicting novel wind-excited firn resonances and point to the plethora of ways these observations could facilitate imaging and monitoring of glacial systems at single, isolated seismometers. Finally, we propose significant instrumental and computational objectives necessary to constrain resonance excitation mechanisms and broadly apply these observations as useful monitoring tools in Antarctica. [ABSTRACT FROM AUTHOR]

Antarctica differs from all other regions in the world, not only from its unique geography, but also in the way humans understand it and have incorporated it into global relations. Considering Antarctica's distinctive landscapes and human relations, this paper discusses aspects of how time is humanly perceived in Antarctica. Basing on elements from different human occupations, nineteenth-century sailor-hunters and current incursions, this discussion approximates different historical groups in their experiences of Antarctica, connecting their personal lives, past and present. Meanwhile, also put into issue are the dualities that separate nature and culture, physical and relative time, and past and present, as well as the related notions of time in itself, perceived time speed and internal time consciousness. [ABSTRACT FROM AUTHOR]

Subglacial lake exploration is of great interest to the science community. RECoverable Autonomous Sonde (RECAS) provides an exploration tool to measure and sample subglacial lake environments while the subglacial lake remains isolated from the glacier surface and atmosphere. This paper presents an electronic control system design of 200 m prototype of RECAS. The proposed electronic control system consists of a surface system, a downhole control system, and a power transfer and communication system. The downhole control system is the core element of RECAS, and is responsible for sonde status monitoring, sonde motion control, subglacial water sampling and in situ analysis. A custom RS485 temperature sensor was developed to cater for the limited size and depth requirements of the system. We adopted a humidity-based measurement to monitor for a housing leak. This condition is because standard leak detection monitoring of water conductivity may be inapplicable to pure ice in Antarctica. A water sampler control board was designed to control the samplers and monitor the on/off state. A high-definition camera system with built-in storage and self-heating ability was designed to perform the video recording in the subglacial lake. The proposed electronic control system is proven effective after a series of tests. [ABSTRACT FROM AUTHOR]