"We are confident in our understanding of ice mass change in Antarctica and its impact on sea levels".
For the total period from 1992 through the present, the ice sheet has lost almost 3 trillion tons of ice, equating to just under 8 millimeters of sea level rise.
One of those studies, co-authored by physical oceanographer and climate scientist Steve Rintoul at Australia's CSIRO contemplates a grim choose-your-own-adventure style environmental dilemma - contrasting what Antarctica is projected to look like in the year 2070 if today's high greenhouse emissions remain unchanged, versus the preferable trajectory if climate action reins in carbon pollution. There's another number, though, that's more pressing: how fast Antarctica is now melting.
In a separate analysis piece in Nature today, climate scientist and Antarctic policy expert Professor Rob DeConto warned that Antarctica may contribute more to sea-level rise than previously thought.
Andrew Shepherd of the University of Leeds, who leads the Ice sheet Mass Balance Inter-comparison Exercise (Imbie), said it had always been suspecting changes in Earth's climate would affect the polar ice sheets.
In Antarctica, it's mostly warmer water causing the melt. By looking at all these types of measurements together, the study authors could more confidently set aside data that did not represent ice cover, Shepherd explained.
Antarctica has lost trillion tonnes of ice to global warming over the past quarter of a century, according to a new study, and that loss has been accelerating in recent years, to triple the rate that was seen prior to 2012. The tally has since jumped to 0.6mm a year.
An worldwide team of polar scientists found that melting in Antarctica has jumped sharply from an average of 76 billion tonnes per year prior to 2012, to around 219 billion tonnes each year between 2012 and 2017.
Antarctica is not the only contributor to sea-level rise. Previous research has shown Greenland-the planet's other major store of ice-lost a trillion tonnes of ice between 2011-2014.
The study also helps clear up some uncertainty that was linked to regional differences in Antarctica.
Two-fifths of that ice loss occurred in the last five years, a three-fold increase in the pace at which Antarctica is shedding its kilometres-thick casing, a consortium of 84 scientists reported in the journal Nature.
That's because as Antarctica's mass shrinks, the ice sheet's gravitational pull on the ocean relaxes somewhat, and the seas travel back across the globe to pile up far away - with USA coasts being one prime destination.
East Antarctica has sometimes been a focus of attention for people who deny the science of global warming.
The new findings are the result of the most complete satellite survey of Antarctic ice sheet change to date, involving 84 scientists from 44 worldwide organizations (including NASA and the European Space Agency).
Unlike single-measurement studies, this team looks at ice loss in 24 different ways using 10 to 15 satellites, as well as ground and air measurements and computer simulations, said lead author Andrew Shepherd of the University of Leeds in England. University of Washington researcher Knut Christianson, who wasn't involved with the study, says we're likely to see "periods of stability interspersed with rapid retreat". "And we find that by combining all of the available measurements we can iron out the problems that individual techniques have".
The Antarctic ice sheet is melting faster than ever - with global sea levels rising more than a half-millimeter every year since 2012, according to scientists.
Antarctic is hardly alone in losing a elephantine amount of ice. This increase has been very small compared to the losses recorded from the rest of the ice sheet, though.
According to a new study by the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE), now considered to be the most complete and up-to-date picture of the changes happening to the Antarctic ice sheet, satellites had been recording a fairly steady rate of ice loss from Antarctica, of around 76 billion tonnes per year, between 1992 and 2012.
Advancements in Earth-observing satellites have enabled researchers to better understand the polar regions.
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