Variability of Antarctic Sea Ice 1979-1998

[1] The principal characteristics of the variability of Antarctic sea ice cover as previously described from satellite passive microwave observations are also evident in a systematically calibrated and analyzed data set for 20.2 years (1979–1998). The total Antarctic sea ice extent (concentration >15%) increased by 11,180 ± 4190 km2 yr−1 (0.98 ± 0.37% (decade)−1). The increase in the area of sea ice within the extent boundary is similar (10,860 ± 3720 km2 yr−1 and 1.26 ± 0.43% (decade)−1). Regionally, the trends in extent are positive in the Weddel Sea (1.4 ± 0.9% (decade)−1), Pacific Ocean (2.0 ± 1.4% (decade)−1), and Ross (6.7 ± 1.1% (decade)−1) sectors, slightly negative in the Indian Ocean (−1.0 ± 1.0% (decade)−1), and strongly negative in the Bellingshausen-Amundsen Seas sector (−9.7 ± 1.5% (decade)−1)). For the entire ice pack, ice increases occur in all seasons, with the largest increase during fall. On a regional basis the trends differ season to season. During summer and fall the trends are positive or near zero in all sectors except the Bellingshausen-Amundsen Seas sector. During winter and spring the trends are negative or near zero in all sectors except the Ross Sea, which has positive trends in all seasons. Components of interannual variability with periods of about 3–5 years are regionally large but tend to counterbalance each other in the total ice pack. The interannual variability of the annual mean sea ice extent is only 1.6% overall, compared to 6–9% in each of five regional sectors. Analysis of the relation between regional sea ice extents and spatially averaged surface temperatures over the ice pack gives an overall sensitivity between winter ice cover and temperature of −0.7% change in sea ice extent per degree Kelvin. For summer some regional ice extents vary positively with temperature, and others vary negatively. The observed increase in Antarctic sea ice cover is counter to the observed decreases in the Arctic. It is also qualitatively consistent with the counterintuitive prediction of a global atmospheric-ocean model of increasing sea ice around Antarctica with climate warming due to the stabilizing effects of increased snowfall on the Southern Ocean.

[1]  Josefino C. Comiso,et al.  INTERANNUAL VARIABILITY IN SUMMER SEA ICE MINIMUM, COASTAL POLYNYAS AND BOTTOM WATER FORMATION IN THE WEDDELL SEA , 2013 .

[2]  C. L. Parkinson Length of the Sea Ice Season in the Southern Ocean, 1988–1994 , 2013 .

[3]  Petra Heil,et al.  East Antarctic sea ice: A review of its structure, properties and drift , 2013 .

[4]  R. Bindschadler,et al.  Response of Antarctic Sea Ice to Uniform Atmospheric Temperature Increases , 2013 .

[5]  S. Rintoul On the Origin and Influence of Adélie Land Bottom Water , 2013 .

[6]  Michael L. Van Woert,et al.  Winter Atmospheric Forcing of the Ross Sea Polynya , 2013 .

[7]  Jeffrey R. Key,et al.  The Estimation of Geophysical Parameters Using Passive Microwave Algorithms , 2013 .

[8]  H. Jay Zwally,et al.  Antarctic Offshore Leads and Polynyas and Oceanographic Effects , 2013 .

[9]  D. Cavalieri,et al.  A Passive Microwave Study of Polynyas Along the Antarctic Wilkes Land Coast , 2013 .

[10]  W. White,et al.  Reestablishing the circumpolar wave in sea ice around Antarctica from one winter to the next , 2001 .

[11]  I. Simmonds,et al.  Current Trends in Antarctic Sea Ice: The 1990s Impact on a Short Climatology , 2000 .

[12]  Josefino C. Comiso,et al.  Variability and Trends in Antarctic Surface Temperatures from In Situ and Satellite Infrared Measurements , 2000 .

[13]  Makiko Sato,et al.  GISS analysis of surface temperature change , 1999 .

[14]  A. Robock,et al.  Global Warming and Northern Hemisphere Sea Ice Extent. , 1999, Science.

[15]  Donald J. Cavalieri,et al.  Arctic sea ice extents, areas, and trends, 1978-1996 , 1999 .

[16]  Donald J. Cavalieri,et al.  Spatial distribution of trends and seasonally in the hemispheric sea ice covers: 1978–1996 , 1999 .

[17]  Donald J. Cavalieri,et al.  Deriving long‐term time series of sea ice cover from satellite passive‐microwave multisensor data sets , 1999 .

[18]  Norden E. Huang,et al.  In search of an elusive Antarctic circumpolar wave in sea ice extents: 1978–1996 , 1999 .

[19]  N. Huang,et al.  The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis , 1998, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[20]  S. Stammerjohn,et al.  Opposing Southern Ocean Climate Patterns as Revealed by Trends in Regional Sea Ice Coverage , 1997 .

[21]  Donald J. Cavalieri,et al.  Observed Hemispheric Asymmetry in Global Sea Ice Changes , 1997 .

[22]  S. O’Farrell,et al.  Transient Climate Change in the CSIRO Coupled Model with Dynamic Sea Ice , 1997 .

[23]  S. Jacobs,et al.  Climate Variability in the Amundsen and Bellingshausen Seas , 1997 .

[24]  Ola M. Johannessen,et al.  Analysis of merged SMMR‐SSMI time series of Arctic and Antarctic sea ice parameters 1978–1995 , 1997 .

[25]  A. Gordon,et al.  Cosmonaut polynya in the Southern Ocean: Structure and variability , 1996 .

[26]  W. White,et al.  An Antarctic circumpolar wave in surface pressure, wind, temperature and sea-ice extent , 1996, Nature.

[27]  Erik Mollo-Christensen,et al.  Oscillatory behavior in Arctic sea ice concentrations , 1996 .

[28]  E. Fahrbach,et al.  Formation and discharge of deep and bottom water in the northwestern Weddell Sea , 1995 .

[29]  Ola M. Johannessen,et al.  The Arctic's shrinking sea ice , 1995, Nature.

[30]  K. Ohshima,et al.  Observations of a street of cyclonic eddies in the Indian Ocean sector of the Antarctic divergence , 1994 .

[31]  C. L. Parkinson,et al.  Spatial patterns in the length of the sea ice season in the Southern Ocean, 1979–1986 , 1994 .

[32]  J. King Recent climate variability in the vicinity of the antarctic peninsula , 1994 .

[33]  H. Hellmer,et al.  Deep and Bottom Water of the Weddell Sea's Western Rim , 1993, Science.

[34]  S. Jacobs,et al.  A recent sea‐ice retreat west of the Antarctic Peninsula , 1993 .

[35]  タカシ ヤマノウチ,et al.  INTERANNUAL FLUCTUATIONS OF SEA ICE EXTENT IN THE ANTARCTIC AND ASSOCIATED ATMOSPHERIC CONDITIONS , 1992 .

[36]  C. C. Wackerman,et al.  Aircraft active and passive microwave validation of sea ice concentration from the Defense Meteorological Satellite Program special sensor microwave imager , 1991 .

[37]  H. Zwally,et al.  Antarctic sea ice variations and seasonal air temperature relationships , 1991 .

[38]  Syukuro Manabe,et al.  Transient responses of a coupled ocean-atmosphere model to gradual changes of atmospheric CO2 , 1991 .

[39]  Per Gloersen,et al.  Recent variations in Arctic and Antarctic sea-ice covers , 1991, Nature.

[40]  David J. Thomson,et al.  Coherence established between atmospheric carbon dioxide and global temperature , 1990, Nature.

[41]  A. Carleton Antarctic sea-ice relationships with indices of the atmospheric circulation of the Southern Hemisphere , 1989 .

[42]  Josefino C. Comiso,et al.  Polynyas in the Southern Ocean , 1988 .

[43]  D. Thomson,et al.  Multiple‐taper spectral analysis of terrestrial free oscillations: part I , 1987 .

[44]  A. Cerami,et al.  Glucose and aging. , 1987, Scientific American.

[45]  Donald J. Cavalieri,et al.  Reduction of weather effects in the calculation of sea ice concentration from microwave radiances , 1986 .

[46]  Josefino C. Comiso,et al.  Characteristics of Arctic winter sea ice from satellite multispectral microwave observations , 1986 .

[47]  T. Wigley,et al.  Variations in Surface Air Temperatures. Part 3: The Antarctic, 1957 82 , 1984 .

[48]  W. Campbell,et al.  Determination of sea ice parameters with the NIMBUS 7 SMMR , 1984 .

[49]  H. Zwally,et al.  Variability of Antarctic Sea Ice: and Changes in Carbon Dioxide , 1983, Science.

[50]  C. L. Parkinson On the Development and Cause of the Weddell Polynya in a Sea Ice Simulation , 1983 .

[51]  D. Cavalieri,et al.  Large-Scale Variations in Observed Antarctic Sea Ice Extent and Associated Atmospheric Circulation , 1981 .

[52]  G. Kukla,et al.  Summer Ice and Carbon Dioxide , 1981, Science.

[53]  D. Martinson,et al.  A Convective Model for the Weddell Polynya , 1981 .

[54]  F. Carsey Microwave Observation of the Weddell Polynya , 1980 .

[55]  J. Middleton,et al.  Variability in the bottom water of the Weddell Sea , 1979 .

[56]  H. Jay Zwally,et al.  Passive microwave images of the polar regions and research applications , 1977, Polar Record.

[57]  D. M. Ellis,et al.  Applied Regression Analysis , 1968 .

[58]  T. H. Jacka,et al.  Detection of temperature and sea-ice-extent changes in the Antarctic and Southern Ocean, 1949-96 , 1998, Annals of Glaciology.

[59]  Donald J. Cavalieri,et al.  Passive microwave algorithms for sea ice concentration: A comparison of two techniques , 1997 .

[60]  D. Cavalieri,et al.  Reduction of weather effects in the calculation of sea-ice concentration with the DMSP SSM/I , 1995, Journal of Glaciology.

[61]  K. Ohshima,et al.  Temperature structure and characteristics appearing on SSM/I images of the Cosmonaut Sea, Antarctica , 1994, Annals of Glaciology.

[62]  Donald J. Cavalieri,et al.  Arctic and Antarctic Sea Ice, 1978-1987: Satellite Passive-Microwave Observations and Analysis , 1992 .

[63]  I. Allison The East Antarctic sea ice zone: Ice characteristics and drift , 1989 .

[64]  Stephen F. Ackley,et al.  Development of Sea Ice in the Weddell Sea , 1989, Annals of Glaciology.

[65]  H. Zwally,et al.  Antarctic Sea Ice, 1973-1976: Satellite Passive-Microwave Observations , 1983 .

[66]  G. Deacon The hydrology of the southern ocean , 1937 .