According to a study led by Eric Rignot from the University of California at Irvine, which looked at details of ice and snow from the entire continent of Antarctica since 1979, Antarctica's crucial ice sheet has been melting for the entire 39 year period, but that is just the tip of the iceberg, so to speak.
The research, published in the Proceedings of the National Academy of Sciences, found that the rate of that ice loss has not been consistent, with ice disappearing faster in each successive decade. Ice loss in Antarctica has increased from 40 gigatons (a gigaton is one billion tons) per year from 1979-90 all the way up to 252 gigatons per year from 2009-17, a 6-fold increase.
And that melt-rate has been accelerating in the most recent decades, up 280% in the second half of the nearly 40 years compared to the first half, Rignot and his colleagues calculated.