Antarctic sea ice extent has shrunk to the lowest level since records began nearly four decades ago, scientists say. According to data from the US National Snow and Ice Data Centre (NSIDC) sea ice in the frozen continent covered just 2.26 million square kilometres on Tuesday, dipping below the earlier 1997 record low. 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, researchers said. 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 state-run news agency ‘Xinhua’ reported.

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.