Physical properties and stratigraphy of surface snow in western Dronning Maud Land, Antarctica

Abstract

Information about the spatial variations of snow properties and of annual accumulation on ice sheets is important if we are to understand the results obtained from ice cores, satellite remote sensing data and changes in climate patterns. The layer structure and spatial variations of physical properties of surface snow in western Dronning Maud Land were analysed during the austral summers 1999/2000, 2000/01 and 2003/04 in five different snow zones. The measurements were performed in shallow (1–2 m) snow pits along a transect extending 350 km from the seaward edge of the ice shelf to the polar plateau. These pits covered at least the last annual accumulation and ranged in elevation from near sea level to 2500 m a.s.l. The Ø18O values and accumulation rates had a good linear correlation with the distance from the coast. The mean accumulation on the ice shelf was 312±28 mm water equivalent (w.e.); in the coastal region it was 215±43 mm w.e. and on the polar plateau it was 92±25 mm w.e. The mean annual conductivity and grain size values decreased exponentially with increasing distance from the ice edge, by 48%/100 km and 18%/100 km respectively. The mean grain size varied between 1.5 and 1.8 mm. Depth hoar layers were a common phenomenon, especially under thin ice crusts, and were associated with low dielectric constant values.

A snow sensor experiment in Dronning Maud Land, Antarctica

“…Upon both sensor installation and retrieval, a snow stratigraphic analysis was made in a separate pit nearby (Kärkäs and others, 2002, 2005; Rasmus and others, 2003). Snow density and temperature profiles (4.3 m deep) were measured using the core extracted during the installation of the battery tube at each site (Fig.…”

“…In FINNARP expeditions, snow accumulation was also examined from snow pits (Kärkäs and others, 2005). The mean net accumulation was 318 mm w.e.…”

Investigation of the spatial variations in synthetic aperture radar backscatter in western Dronning Maud Land, Antarctica

“…The approximate annual accumulation from snow pit data along a traverse of Dronning Maud Land was measured during expeditions in 1988−1989 and 1993−1994 [22,25]. Further data has been published from more recent investigations [26]. Isaksson [22] observed quite large variations in accumulation over relatively short distances and suggested megadunes may affect local patterns of accumulation.…”

“…Surface slopes are a further factor in spatial variation with steeper surfaces experiencing greater variation [23]. In the region we address in this paper, occasional investigations have been made using snowpit and shallow firn cores [22,25,26]. The approximate annual accumulation from snow pit data along a traverse of Dronning Maud Land was measured during expeditions in 1988−1989 and 1993−1994 [22,25].…”

The influence of Nunataks on atmospheric boundary layer convection during summer in Dronning Maud Land, Antarctica

“…To implement new and more realistic surface information into the models, knowledge on surface and soil properties is required. Kärkäs et al [] suggest further work using more detailed measurements of the effects of summer melting and evaporation of the snow on nunataks. While convective heat plumes have been studied in Antarctica, we are unaware of other peer‐reviewed model studies detailing the influence of nunataks on the ABL.…”