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Supraglacial lakes form in Antarctic blue ice regions from penetration of solar radiation into the ice in summer. Three lakes were mapped for their structure in summers 2004-05 and 2010-11 in western Dronning Maud Land, and one was also examined for the radiation budget. The lake body consisted of two layers, each ,1 m thick: an upper layer with a thin ice layer on top and main body of liquid water, and a lower layer containing slush and hard ice sub-layers. A sediment-rich slush pocket was found at the bottom. Hydraulic conductivity of the lake body was 0.25-30 cm s -1 depending on the stage of evolution, with 6.3 cm s -1 for closely packed slush. Albedo of the lake was 0.4-0.6 and light attenuation coefficient was 0.5-0.7 m -1 . The formation and the depth scale of the lakes are determined by the light attenuation distance and thermal diffusion coefficient, limiting the growth to less than about 1.5 m in one summer. The potential winter growth is more and thus the lakes freeze up in winter in the present climatic conditions.

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Extensive glaciological field measurements were carried out on the ice cap Vestfonna as well as on the minor ice body De Geerfonna (Nordaustlandet, Svalbard) within the framework of IPY Kinnvika. Field campaigns were conducted during the period 2007-2010 in spring (April/May) and summer (August). In this study we compile and present snow cover information obtained from 22 snow pits that were dug on Vestfonna during this period. Locations are along two transects on the northwestern, land terminating slope of the ice cap, on its central summit, Ahlmann Summit, and at a set of several other locations in the eastern and northern part of the ice cap. Snow-cover information acquired from four snow pits on adjacent De Geerfonna is also incorporated in this study. Field data are analysed regarding snow stratigraphy, snow density, snow hardness and snow temperature. Results reveal mean snow densities of around 400 kg m -3 for the snowpack of Vestfonna with no apparent spatial or interannual variability. A distinctly higher value of more than 450 kg m -3 was obtained for De Geerfonna. A spatial comparison of snow water equivalents above the previous end-ofsummer surface serves for obtaining insights into the spatial distribution of snow accumulation across Vestfonna. Altitude was found to be the only significant spatial parameter for controlling snow accumulation across the ice cap. IntroductionIn the framework of the IPY (International Polar Year) Kinnvika project ) and its follow-on activities several field campaigns with focus on snow-cover related fieldwork were carried out during seven individual field campaigns on Nordaustlandet, Svalbard, in the period 2007-2010. Snow cover conditions were investigated on the ice cap Vestfonna as well as the neighbouring minor ice body De Geerfonna. Snow-cover related fieldwork on Vestfonna focused on two transects along the northwestern slope of the ice cap and on its main ridges, including the two highest points,