6 samples of a multi century phenomenon and you are ringing an alarm bell !
the chart smacks more of searching around for a chart that shows a decline to prop up the "ice is in trouble narrative".
ice extent ( recovered from 2008/12 ) , ice age ( recovered again from 2012 ), ice thickness ( recovered ), ice refreeze date ( recovered ), polar bear population ( highest its ever been )
now its ice mass that is the panic chart of the day. but 6 samples, its just not enough