Evolution of first‐year and second‐year snow properties on sea ice in the Weddell Sea during spring‐summer transition

Observations of snow properties, superimposed ice, and atmospheric heat fluxes have been performed on first-year and second-year sea ice in the western Weddell Sea, Antarctica. Snow in this region is particular as it does usually survive summer ablation. Measurements were performed during Ice Station Polarstern (ISPOL), a 5-week drift station of the German icebreaker RV Polarstern. Net heat flux to the snowpack was 8 W m−2, causing only 0.1 to 0.2 m of thinning of both snow cover types, thinner first-year and thicker second-year snow. Snow thinning was dominated by compaction and evaporation, whereas melt was of minor importance and occurred only internally at or close to the surface. Characteristic differences between snow on first-year and second-year ice were found in snow thickness, temperature, and stratigraphy. Snow on second-year ice was thicker, colder, denser, and more layered than on first-year ice. Metamorphism and ablation, and thus mass balance, were similar between both regimes, because they depend more on surface heat fluxes and less on underground properties. Ice freeboard was mostly negative, but flooding occurred mainly on first-year ice. Snow and ice interface temperature did not reach the melting point during the observation period. Nevertheless, formation of discontinuous superimposed ice was observed. Color tracer experiments suggest considerable meltwater percolation within the snow, despite below-melting temperatures of lower layers. Strong meridional gradients of snow and sea-ice properties were found in this region. They suggest similar gradients in atmospheric and oceanographic conditions and implicate their importance for melt processes and the location of the summer ice edge.

[1]  Vladimir F. Radionov,et al.  Snow Depth on Arctic Sea Ice , 1999 .

[2]  Ian Allison,et al.  Winter snow cover variability on East Antarctic sea ice , 1998 .

[3]  C. Haas,et al.  The importance of diurnal processes for the Seasonal cycle of Sea-ice microwave brightness temperatures during early Summer in the Weddell Sea, Antarctica , 2006, Annals of Glaciology.

[4]  Christian Haas,et al.  Reduced ice thickness in Arctic Transpolar Drift favors rapid ice retreat , 2008 .

[5]  R. Jordan.  A One-dimensional temperature model for a snow cover : technical documentation for SNTHERM.89 , 1991 .

[6]  M. Drinkwater,et al.  Sea ice, atmosphere and upper ocean variability in the Weddell Sea, Antarctica , 2001 .

[7]  Ian Allison,et al.  Snow on Antarctic sea ice , 2001 .

[8]  Donald K. Perovich,et al.  Seasonal evolution of the albedo of multiyear Arctic sea ice , 2002 .

[9]  K. Ohshima,et al.  Relationship between the upper ocean and sea ice during the Antarctic melting season , 1997 .

[10]  C. Haas,et al.  High radar-backscatter regions on Antarctic sea-ice and their relation to sea-ice and snow properties and meteorological conditions , 2011 .

[11]  Bin Cheng,et al.  Model experiments on snow and ice thermodynamics in the Arctic Ocean with CHINARE 2003 data , 2008 .

[12]  Ice.  The international classification for seasonal snow on the ground , 1990 .

[13]  D. Perovich.  On the aggregate-scale partitioning of solar radiation in arctic sea ice during the Surface Heat Budget of the Arctic Ocean (SHEBA) field experiment , 2005 .

[14]  Christian Haas,et al.  Winter Snowcover on Sea Ice in the Weddell Sea , 1997 .

[15]  Edgar L. Andreas,et al.  On the Differences in Ablation Seasons of Arctic and Antarctic Sea Ice , 1982 .

[16]  Bruce C. Elder,et al.  Exploring Arctic Transpolar Drift During Dramatic Sea Ice Retreat , 2008 .

[17]  H. Hellmer,et al.  Early summer thermohaline characteristics and mixing in the western Weddell Sea , 2008 .

[18]  C. Haas,et al.  Surface properties and processes of perennial Antarctic sea ice in summer , 2001, Journal of Glaciology.

[19]  Matthew Sturm,et al.  The Winter Snow Cover of the West Antarctic Pack Ice: Its Spatial and Temporal Variability , 2013 .

[20]  T. Vihma,et al.  Weddell Sea ice drift: Kinematics and wind forcing , 1996 .

[21]  C. Haas,et al.  Observations of superimposed ice formation at melt-onset on fast ice on Kongsfjorden, Svalbard , 2002 .

[22]  Marcel Nicolaus,et al.  A model study of differences of snow thinning on Arctic and Antarctic first-year sea ice during spring and summer , 2006, Annals of Glaciology.

[23]  C. Haas,et al.  Tidal forcing on sea-ice drift and deformation in the western Weddell Sea in early austral summer, 2004 , 2008 .

[24]  H. Hellmer,et al.  The ISPOL drift experiment , 2008 .

[25]  S. Colbeck,et al.  The geometry and permittivity of snow at high frequencies , 1982 .

[26]  J. Bareiss,et al.  ISPOL weather conditions in the context of long-term climate variability in the north-western Weddell Sea , 2008 .

[27]  Ari Sihvola,et al.  Snow Fork for Field Determination of the Density and Wetness Profiles of a Snow Pack , 1986, IEEE Transactions on Geoscience and Remote Sensing.

[28]  P. Wadhams,et al.  Characteristics and distribution patterns of snow and meteoric ice in the Weddell Sea and their contribution to the mass balance of sea ice , 1994 .

[29]  D. Barber,et al.  Role of SAR in Surface Energy Flux Measurements Over Sea Ice , 1998 .

[30]  D. Marbouty.  An experimental study of temperature-gradient metamorphism , 1980 .

[31]  Raymond A. Shaw,et al.  Crystal structure, stable isotopes (δ18O), and development of sea ice in the Ross, Amundsen, and Bellingshausen seas, Antarctica , 1994 .

[32]  P. Lemke,et al.  Effects of the snow cover on Antarctic sea ice and potential modulation of its response to climate change , 1995 .

[33]  T. Fichefet,et al.  Simulating the mass balance and salinity of Arctic and Antarctic sea ice 2: Importance of sea ice salinity variations , 2009 .

[34]  M. Mcphee.  Physics of early summer ice/ocean exchanges in the western Weddell Sea during ISPOL , 2008 .

[35]  H. Eicken,et al.  Meltwater circulation and permeability of Arctic summer sea ice derived from hydrological field experiments , 2003, Journal of Glaciology.

[36]  David G. Long,et al.  Mapping the Progression of Melt Onset and Freeze-Up on Arctic Sea Ice Using SAR and Scatterometry , 1998 .

[37]  K. Keay,et al.  Mean Southern Hemisphere Extratropical Cyclone Behavior in the 40-Year NCEP–NCAR Reanalysis , 2000 .

[38]  P. Langhorne,et al.  Temporal evolution of decaying summer first-year sea ice in the Western Weddell Sea, Antarctica. , 2008 .

[39]  Gary A. Maykut,et al.  The Surface Heat and Mass Balance , 1986 .

[40]  R. M. Koerner,et al.  Some Observations on Superimposition of Ice on the Devon Island Ice Cap, N.W.T. Canada , 1970 .

[41]  D. Perovich.  The Optical Properties of Sea Ice. , 1996 .

[42]  I. Frolov.  The arctic basin : results from the Russian drifting stations , 2005 .

[43]  Donald K. Perovich,et al.  Spectral albedos of sea ice and incident solar irradiance in the southern Beaufort Sea , 1984 .

[44]  Bin Cheng,et al.  Superimposed ice formation and surface energy fluxes on sea ice during the spring melt–freeze period in the Baltic Sea , 2006, Journal of Glaciology.

[45]  C. Haas,et al.  Sea ice and snow thickness and physical properties of an ice floe in the western Weddell Sea and their changes during spring warming , 2008 .

[46]  G. Maykut,et al.  Some results from a time‐dependent thermodynamic model of sea ice , 1971 .

[47]  C. Haas,et al.  Copepods in sea ice of the western Weddell Sea during austral spring 2004 , 2008 .

[48]  Edgar L. Andreas,et al.  Year on ice gives climate insights , 1999 .

[49]  M. Anderson,et al.  Spatial and temporal variability in snowmelt onset over Arctic sea ice , 2001, Annals of Glaciology.

[50]  T. Vihma,et al.  Radiative and turbulent surface heat fluxes over sea ice in the western Weddell Sea in early summer , 2009 .

[51]  Seasonal variations in the properties and structural composition of sea ice and snow cover in the Bellingshausen and Amundsen Seas, Antarctica , 1997 .

[52]  J. Tison,et al.  Superimposed-ice formation in summer on Ross Sea pack-ice floes , 2004, Annals of Glaciology.

[53]  Ian Allison,et al.  East Antarctic sea ice: Albedo, thickness distribution, and snow cover , 1993 .

[54]  J. Curry,et al.  Applications of SHEBA/FIRE data to evaluation of snow/ice albedo parameterizations , 2001 .

[55]  M. Jeffries,et al.  Seasonal contrasts in snow-cover characteristics on Ross Sea ice floes , 2001, Annals of Glaciology.

[56]  Leif Toudal Pedersen,et al.  Simulation of the Ku-band Radar altimeter sea ice effective scattering surface , 2006, IEEE Geoscience and Remote Sensing Letters.

[57]  M. Holland,et al.  The influence of sea ice physics on simulations of climate change , 2001 .

[58]  Donald K. Perovich,et al.  Sunlight, water, and ice: Extreme Arctic sea ice melt during the summer of 2007 , 2008 .

[59]  Marcel Nicolaus,et al.  Satellite microwave observations of the interannual variability of snowmelt on sea ice in the Southern Ocean , 2009 .

[60]  K. Ohshima,et al.  Physical, structural, and isotopic characteristics and growth processes of fast sea ice in Lützow‐Holm Bay, Antarctica , 1997 .