Figures from the U.S. National Snow and Ice Data Center (NSIDC) on Wednesday show that sea ice in the frozen continent covered just 2.26 million square km, lower than the lowest level seen around this time in 1997.
Mark Serreze, director of the NSIDC, told reporters that the new data still need to be confirmed with a few days of measurements.
The sea ice is likely to decrease further as it usually melts to its smallest for the year at the end of February in the summer of southern hemisphere.
Sea ice at both poles has been expected to decline as the Earth heats up due to man-made global warming. However, the conditions in the Antarctic are much more variable.
The average extent of sea ice around the South Pole has tended to expand in many recent years and hit a record high of around 20.16 million square km in September 2014.
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