Sea ice in the Antarctic has shrunk to its lowest level since records began nearly four decades ago, preliminary US satellite data has shown.

Figures from the US National Snow and Ice Data Centre (NSIDC) on Wednesday showed that sea ice in the frozen continent covered just 2.26 million sq.km on Tuesday, lower than the lowest level seen around this time in 1997, Xinhua news agency reported.

Mark Serreze, Director of the NSIDC, said 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 sq.km in September 2014.