Abstract
An iterative classification technique based on Special Sensor Microwave/Imager data is used to estimate the total daily circum-Antarctic coastal polynya area for 1992–2008. The average wintertime (June to September) area is estimated at 245,000 ± 10,000 km2, and varies between 210,000 km2 (1997) and 281,000 km2 (2007). The polynyas along East-Antarctica (60 to 160°E) contribute about 40% to this area. The most persistent polynyas are located along East Antarctica: Lars-Christensen Coast (LCC), Prydz Bay, Western Davis Sea, Mertz Glacier, and in the Ross Sea: Ross Ice Shelf and Terra Nova Bay. The polynya at the LCC is observed on 110 ± 5 days during winter for 1992–2008. It is the most persistent of the observed polynyas, covering an average area of 2400 km2 on more than 90 days. Trends in the average wintertime area of the major coastal polynyas during 1992–2008 are small and not significant.
