Environment

Antarctic ice loss and sea level rise rates have tripled since 2012

Antarctic ice loss and sea lev...
Crevasses near Pine Island Glacier, Antarctica, which is one of the hardest hit regions
Crevasses near Pine Island Glacier, Antarctica, which is one of the hardest hit regions
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The Antarctic Peninsula from the air
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The Antarctic Peninsula from the air
Sunset at Adelaide Island, Antarctic Peninsula
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Sunset at Adelaide Island, Antarctic Peninsula
Crevasses near Pine Island Glacier, Antarctica, which is one of the hardest hit regions
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Crevasses near Pine Island Glacier, Antarctica, which is one of the hardest hit regions
A graph highlighting the Antarctic ice sheet's contribution to global sea level rise between 1992 and 2017
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A graph highlighting the Antarctic ice sheet's contribution to global sea level rise between 1992 and 2017

An international team of scientists from over 40 organizations around the world has completed the most comprehensive assessment of how Antarctica's ice mass is changing – and as expected, the results are worrying. The Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE) shows that the rate of ice loss – and the resulting sea level rise – has tripled since 2012, compared to a more steady rate over the last 25 years.

This latest assessment involves 84 scientists from more than 40 institutions, and combines data from 24 satellite surveys. It follows in the footsteps of the first IMBIE conducted in 2012, and paints a particularly grim picture of the years between then and 2017.

The team studied changes in the ice mass of Antarctica between 1992 and 2017, and the associated contributions to the rising sea level. Before 2012, Antarctic ice was receding at a relatively steady rate of about 83.8 billion tons a year. In the years after that, the annual ice loss appears to have accelerated to a rate of 241.1 billion tons – around three times the previous rate.

Of course all that ice has to go somewhere, and the resulting sea level rise has also accelerated. The IMBIE researchers say that the sea level has climbed by 7.6 mm (0.3 in) since 1992, with almost half of that amount – 3 mm (0.12 in) – occurring in the five years between 2012 and 2017.

A graph highlighting the Antarctic ice sheet's contribution to global sea level rise between 1992 and 2017
A graph highlighting the Antarctic ice sheet's contribution to global sea level rise between 1992 and 2017

"We have long suspected that changes in Earth's climate will affect the polar ice sheets," says Andrew Shepherd, co-lead researcher on the project. "Thanks to the satellites that our space agencies have launched, we can now track their ice losses and global sea-level contribution with confidence. According to our analysis, there has been a step increase in ice losses from Antarctica during the past decade, and the continent is causing sea levels to rise faster today than at any time in the past 25 years."

West Antarctica has been the hardest hit, losing 175.3 billion tons of ice per year since 2012 – up from 58.4 billion tons a year during the 1990s. The Antarctic Peninsula in the north saw an increase of 27.6 billion tons each year since the beginning of the century, including the giant iceberg that broke off from the Larsen C ice shelf last year.

Sunset at Adelaide Island, Antarctic Peninsula
Sunset at Adelaide Island, Antarctic Peninsula

Interestingly, the East Antarctic ice shelf fared better, actually gaining about 5.5 billion tons of ice each year on average. Unfortunately, that's a drop in the bucket compared to the speed with which the rest of the continent is melting.

"Satellites have given us an amazing, continent-wide picture of how Antarctica is changing," says Pippa Whitehouse, an author on the study. "The length of the satellite record now makes it possible for us to identify regions that have been undergoing sustained ice loss for over a decade. The next piece of the puzzle is to understand the processes driving this change. To do this, we need to keep watching the ice sheet closely, but we also need to look back in time and try to understand how the ice sheet responded to past climate change."

The latest findings are discussed in the IMBIE video below.

The research was published in the journal Nature.

Assessing Antarctic ice loss

Sources: ESA, JPL

9 comments
VincentWolf
The rich will take advantage of all this by buying up properties along new sea shores. The poor will just get poorer.
Catweazle
The most recent analysis by Jay Zwally of NASA appears to disagree. https://www.nasa.gov/feature/goddard/nasa-study-mass-gains-of-antarctic-ice-sheet-greater-than-losses NOAA's sea level data do not show any increase in rate of change of sea level rise over the past three decades either. https://tidesandcurrents.noaa.gov/sltrends/sltrends.html So no cause for alarm.
GregVoevodsky
VincentWolf - so the poor and middle class who sell their new beach front properties won't become rich?! Save me from your ignorant socialist BS.
MD
GregVoevodsky: I think VincentWolf was havin a laugh. The Rich already own the houses of the poor... The middleclasses are happy to sell their second-row homes to the real wealthy and move forward to the Existing seashore - seaside home is the sign to everyone that you "have arrived", even if it was a "Bargain"- ready for Apocalyptic inundation and disposession by the sea.. We all Joke, because we know that in reality the rich are buying all the fishing shacks (overinflating prices, and then they don't even fish) on the waters edge that they can - firstwave disinformation perhaps.... To see if the science is real follow the money. lol. Don't listen to the real scientist or you will be bamboozled by statistics. BTW "socialist BS" may be ideology, or realworld observation, who can tell?? (This is very lighthearted, nothing here is too serious)
ljaques
OMGwereallgonnadieagain! Just last year, the google timelapse site showed that two thirds of glaciers had GAINED (or retained), not lost, ice over time.
Josh C
CatW is right. Same in Greenland: https://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/ If you scroll down a bit, 2017-2018 is actually higher than 2011-2012.
Coachtriplett
And New York is already under water according to Al Gore. Ridiculous.
christopher
I'm so sick of reading this alarmist garbage with fake statistics and ridiculous claims. I am double-sick of all the scientists who are too scared to risk their reputation by calling out all the bogus data that gets spewed into their face. None of those numbers are accurate - the suggestion that 84 "scientists" put their names to it is either ridiculous, or 84 tree huggers all got their qualifications from a DIY website and scammed the heck out of that Journal.
Synchro
@christopher: If you dispute data and findings, say so, and provide evidence. That's how it works. It's entirely likely that different studies will conflict - but that doesn't make them invalid, it just means that we're missing something. You will never find out what that is by throwing ad-hominem insults at those trying to do it right. What we need is better data - the NASA study linked above says that it's very difficult to measure these things accurately, so they are launching the ICESat-2 mission this year to do precisely that, measuring altitude much more accurately over the whole of antarctica every 80cm. On their site they also note that the study mentioned in this article (which NASA took part in too) is more comprehensive and accurate than the earlier one they did. That's how you do science.