Pezza, A.B., Rashid, H.A. and Simmonds, I. 2012. Climate links and recent extremes in Antarctic sea ice, high-latitude cyclones, Southern Annular Mode and ENSO. Climate Dynamics 38: 57-73.
According to Pezza et al. (2012) there has been a modest increasing trend in sea ice extent (SIE) around Antarctica over the era of satellite coverage, citing the studies of Watkins and Simmonds (2000), Zwally et al. (2002), Parkinson (2004), Turner et al. (2007) and Comiso and Nishio (2008).
In a broader study of the climatic link between the Southern Annular Mode and Southern Hemisphere SIE, Pezza et al. derived a history of Antarctic SIE for the period stretching from autumn 1979 to autumn 2008, based on remotely-sensed Nimbus-7 SMMR and DMSP SSM/I passive microwave data from the National Aeronautics and Space Administration’s National Snow and Ice Data Center. In doing so the three Australian scientists report that modest positive SIE trends were observed during all seasons, noting that “the absolute trends over spring and autumn are the most pronounced, with an increase of about half a million square kilometers over the whole period.” In percentage terms, they say “there is an increase between 2 and 3% during winter and spring and from 5 to 7% during the low ice season.” Of special note is their finding that “the greatest SIE on record observed during the low sea ice season occurred repeatedly in December 2007-February 2008 and March-May2008,” with both records being “far greater” than all previous records: 6% greater in the first case and 8% greater in the second. (more…)