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The article presents a thermo-hydrodynamic modelling study of the low-elevation blue-ice areas in Antarctica where significant amounts of subsurface liquid water during summer can be contained and absorption of shortwave radiation can be experienced. The study of the phenomenon is using the existing 2-D (x-z) model and is improved by changing the optical and thermal boundary conditions together with the optical attenuation coefficient. Significant effect of spatial variability of snow on subsurface melting has been found out.

The West Antarctic rift system differs from other volcanically active rift systems in two unusual respects: (1) the rift floor lies 1000-2000 m lower in elevation than others, and (2) four interior ice-filled troughs extend between 1500 m and 2555 m below sea level. Two troughs are more than twice the depth of Lake Baikal, the world's deepest lake. The Marie Byrd Land dome, by contrast, compares closely with the intra-rift Kenyan and Ethiopian domes in the East African rift. Comparisons between these rift systems suggest (1) that the West Antarctic interior is relatively cool and volcanically inactive, (2) that there is likely to have been an episode of extension during Neogene time in the deep interior basins, and (3) that dome uplift and basin subsidence have greatly changed the West Antarctic landscape over the past 25 m.y. [ABSTRACT FROM AUTHOR]

The history of Lake Vostok, the huge East Antarctic subglacial lake, is critical to the unique biota expected in this extreme environment. One theory is that the lake existed prior to the mid-Miocene glaciation of the continent at around 15 million years ago, survived the subsequent period of ice growth intact, and then remained relatively stable beneath its thick ice cover to the present day. The alternative is that the lake was formed by subglacial water flow into an existing and/or glacially eroded trough after the ice sheet reached its present configuration. Here, the onset of persistent ice cover in Antarctica is reviewed and a simple model for continental ice growth discussed. This information is used to argue against the preglacial origin of subglacial lakes. Lake Vostok is large because ice flows essentially perpendicular to the trough's long axis, permitting the slopes of the ice surface and the ice-water interface to be low. During the onset of glaciation ice flow across Lake Vostok would have been more akin to flow across an ice marginal trough such as the Astrolabe Subglacial Basin, which holds the thickest ice in Antarctica: 4776 m where the bed is over 2 km below the sea level. Hence, regardless of whether Lake Vostok was a lake prior to glaciation, its trough is likely to have been occupied by grounded ice during the period of ice growth. Although the lake is stable today, its size and extent will be affected by ice sheet changes that occur over glacial-interglacial cycles. Such changes are reviewed and the potential consequences for the lake's volume are discussed. [ABSTRACT FROM AUTHOR]