By Paul Homewood
A new study has found that the Antarctic ice sheet started growing again between 2021 and 2023, confounding the warnings of doom continually fed to us.
Abstract
To accurately evaluate the Antarctic Ice Sheet (AIS) mass change rate and its spatiotemporal characteristics, we derive the AIS mass change series from April 2002 to December 2023 using an improved point-mass model approach with data-driven regularization matrices and iteratively determined multiple regularization parameters. Then, we analyze the spatio-temporal characteristics of the mass change rate over the AIS, focusing on four glacier basins in the Wilkes Land-Queen Mary Land (WL-QML) region of the East AIS (EAIS), namely the Denman, Moscow, Totten, and Vincennes Bay glacier basins. The results indicate that the AIS contribution to GMSL (global mean sea level) rise peaked at 5.99±0.43 mm in February 2020, followed by a mass gain period lasting over three years, ultimately resulting in a total GMSL contribution of 5.10±0.52 mm by the end of 2023. Moreover, the AIS experienced substantial mass loss during the 2011–2020 period, with a rate of 142.06±56.12 Gt a−1, mainly due to intensified mass loss in the West AIS and the WL-QML region of the EAIS. Further analysis shows that the mass loss rate of the four glacier basins in the WL-QML region during the 2011–2020 period increased by 47.64±8.14 Gt a−1 compared with the 2002–2010 period, with expanded areas of mass loss spreading inland. Notably, the Vincennes Bay and Denman glacier basins transitioned from mass balance and accumulation to intense mass loss, respectively. An in-depth investigation reveals that the increased ice discharge and decreased SMB (surface mass balance) contribute 27.47% and 72.53%, respectively, to the intensified mass loss of the four glacier basins. Overall, the study presents the mass change characteristics of the AIS over the past 22 years, highlights the instability of four important glacier basins in the EAIS, and provides valuable scientific insights for related polar research.
https://link.springer.com/article/10.1007/s11430-024-1517-1
There should be no great surprise about this – NASA themselves show the same sort of recovery since 2020:
https://climate.nasa.gov/vital-signs/ice-sheets/?intent=121
But this is where it all starts to get muddied. The NASA graph is deliberately designed to misinform, suggesting a precipitous decline in Antarctic mass since 2000.
This is what the picture actually looks like:
Antarctic ice mass is reckoned to be 24,380,000 gigatonnes. NASA’s claimed loss of 136 Gt a year is just 0.0005% of that.
The ice is said to be about 2 km thick, so they are claiming they can measure the height of the ice to an accuracy of 1 cm across the whole continent, which is plainly absurd.
And we must also remember that ten years ago NASA’s own Jay Zwally found that the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001, and 82 billion tons of ice per year between 2003 and 2008. This totally contradicts what they are claiming now.
So who is right? Is the ice sheet growing or shrinking? The reality is that we simply cannot know, because whatever the changes are they are too tiny to measure with any certainty.
Interestingly, NASA’s article in 2015, covering the Zwally study, reported:
“The new study highlights the difficulties of measuring the small changes in ice height happening in East Antarctica,” said Ben Smith, a glaciologist with the University of Washington in Seattle who was not involved in Zwally’s study.
"Doing altimetry accurately for very large areas is extraordinarily difficult, and there are measurements of snow accumulation that need to be done independently to understand what’s happening in these places,” Smith said.
It is also highly relevant that since September 2018, measurements of the icecap have been monitored by a new NASA satellite, ICESat-2, which naturally is much more accurate than its predecessor. The latest measurements showing a recovery in ice mass therefore must be considered more reliable than earlier claims of mass loss.
All of these Antarctic studies share the same childishly naive view that climate never changed before the 21st century. What possible significance does a graph beginning in 2001 have, when we have no idea of what happened to the ice sheet during the previous 10,000 years.
There is evidence that the recent recovery is due to heavier snowfall, which the authors describe as “anomalous”. But how do they know the earlier period was not anomalously low?
In fact, NASA reported in 2015:
Zwally said that while other scientists have assumed that the gains in elevation seen in East Antarctica are due to recent increases in snow accumulation, his team used meteorological data beginning in 1979 to show that the snowfall in East Antarctica actually decreased by 11 billion tons per year during both the ERS and ICESat periods. They also used information on snow accumulation for tens of thousands of years, derived by other scientists from ice cores, to conclude that East Antarctica has been thickening for a very long time.
“At the end of the last Ice Age, the air became warmer and carried more moisture across the continent, doubling the amount of snow dropped on the ice sheet,” Zwally said.
The extra snowfall that began 10,000 years ago has been slowly accumulating on the ice sheet and compacting into solid ice over millennia, thickening the ice in East Antarctica and the interior of West Antarctica by an average of 0.7 inches (1.7 centimeters) per year. This small thickening, sustained over thousands of years and spread over the vast expanse of these sectors of Antarctica, corresponds to a very large gain of ice – enough to outweigh the losses from fast-flowing glaciers in other parts of the continent and reduce global sea level rise.
It really is a no-brainer! Polar regions warm because of the influx of milder, moist air from lower latitudes, which in turn brings more snow. We know that Antarctic sea ice has shrunk in the last few years, precisely because of the predominance of northerly winds; the two phenomena are connected.
And we also know that sea ice grew between the 1980s and 2010s, due to the same factors which led to reduced snowfall. Both events are part of the Southern Annular Mode, which describes shifts in the position and strength of the westerly wind belt around Antarctica, which in turn influences the strength and location of the polar jet stream.
But what Zwally has identified is that the same processes have been going since the Ice Age ended.
There is not a jot of evidence that the loss of ice mass claimed by NASA between 2002 and 2020 was in any way unprecedented or unusual.
FOOTNOTE
The NASA article referred to above now states:
This of course is a nonsense and a lie.
Plainly Zwally’s for 1992 to 2008 are just as valid now as they were then. Nor has NASA said that the study was in any way inaccurate or faulty. Indeed, Zwally’s study is up on the Journal of Glaciology.
The inference is obvious – Zwally’s conclusions that the Antarctic ice sheet has been growing for all of this time is politically inconvenient for NASA.