We have relatively short records of the extent of sea ice across the polar regions and can only accurately examine trends since sophisticated microwave instruments became available on the polar orbiting satellites in the late 1970s. However, the records do show that since that time the two polar regions have experienced very different trends in ice extent. Arctic sea ice has been declining in extent in every month of the year, but with the maximum loss of almost 14% per decade being found in September. In contrast, sea ice extent around the Antarctic has increased in every month of the year with the largest increase being almost 4% per decade in March. The contrasting nature of the changes was highlighted in September 2012 when both polar regions experienced new record extents of sea ice for the satellite era. On 16 September the Arctic sea ice extent reached a new minimum level of 3.41m sq km, beating the previous record minimum that occurred in 2007. However, in the Antarctic there was a new record maximum extent of 19.72m sq km on 24 September, exceeding the previous record of 19.59m sq km, which occurred on 24 September 2006. In September 2013 there was even more sea ice across the Southern Ocean, beating the 2012 record.