#Icesheet

MPI für MeteorologieMPI_Meteo@wisskomm.social
2026-02-24

🧊 How stable is Greenland’s ice sheet? New #MPIM research reveals 4️⃣ different steady states of the Greenland #IceSheet under a pre-industrial climate. Using a novel fully-coupled Earth System-Ice Sheet Model, Malena Andernach et al. found a critical threshold of 70-83% of pre-industrial ice volume, below which 50-80% of its current volume would be irreversibly lost even if returning to pre-industrial CO2 concentrations.

🗺️ CC BY 4.0 Andernach et al. 2026
📖 tc.copernicus.org/articles/20/
#ClimateChange

Four maps of Greenland with different sizes of the Greenland Ice Sheet, ranging from large on the left to small on the right.
NewsletterTFnewsletterTF
2026-02-22

Greenland Ice Sheet Shows Unexpected Internal Dynamics

Scientists found strange things happening deep inside the Greenland Ice Sheet. This changes how we think about ice and sea levels.

, , , ,

newsletter.tf/greenland-ice-mo

NewsletterTFnewsletterTF
2026-02-22

New studies show that the Greenland Ice Sheet has surprising movements deep inside. Scientists are studying these to better understand how the ice moves and how it might affect sea levels.

, , , ,

newsletter.tf/greenland-ice-mo

Greenland thoughts from Antarctica..

I’m in Antarctica and yet I have been getting contact from journalists because Greenland is all over the press at the moment for all the wrong reasons. It’s reasonable I think to worry about what the various deranged threats towards Greenland will mean for us all also outside of Greenland. But I also think about (and yes, worry) about the friends I’ve made in Greenland over the years. Let’s hope common sense prevails and we can step back from the brink, and concentrate on the really long term problems that we are still rapidly storing up for ourselves.

Greenland is also on my mind, not just because of geopolitics, but also because the Copernicus Climate service has just put out their annual global climate highlights* for 2025 report with some disturbing results from Antarctica.

A few months ago we had a paper published called the Greenlandification of Antarctica, in which we argue that the changes in the Antarctic cryosphere increasingly resemble those we have previously observed in Greenland and the Arctic. To see the future of Antarctica, look at Greenland.

It’s been a busy time preparing for fieldwork and I didn’t manage to write anything here about it at the time, but this few eye-opening figure rather supports some of our arguments.

In this graphic, the 2025 temperature over the Antarctic region was 1.06°C higher than the average between 1991 and 2020 (a temperature anomaly). This is actually higher than any other region except the Arctic, where the temperature anomaly was reported to be 1.37°C above the 30 year average (bear in mind also that between 1991 and 2020, the temperature was also much increasing, so we’re not comparing with a pre-industrial climate here). Polar amplification was predicted long ago and as those first experiments found, it also is seen more in the Arctic than the Antarctic – but these results are a first hint of the amplification that is perhaps appearing now and may come to stay in the Antarctic.

In our paper we show the figure below (many thanks to illustrator Jagoba Malumbres-Olarta for the fine work), which shows five different cryosphere properties that are changing: 1) shrinking sea ice, 2) glacier velocities that show a seasonal cycle (mostly detected on the peninsula so far, though there are indications that Totten glacier for example has some kind of seasonal cycle, possibly modulated by sea ice), 3) total ice sheet mass loss, 4) ice shelf area and 5) annual mean surface temperature. In virtually all, the changes look very similar between Greenland and Antarctica, but with the crucial difference that the speed of changes is so far faster and more advanced in Greenland.

From Mottram et al., 2025: The Greenlandification of Antarctica. Original caption:
a, Commonalities include decline in sea ice extent from 1980 to 20232, with notable step-like changes in both poles. b, Seasonal glacier velocities are shown for two representative marine terminating glaciers, Kangilernata Sermia in Greenland13 and Hotine Glacier on the AP9, both now displaying similar seasonal dynamics. c, Both ice sheets show an accelerating total mass loss measured by GRACE satellites8d, Multi-sensor records of ice shelf area loss in Antarctica11 show a steeper decline than Greenland7 as Arctic ice shelves were largely lost in the pre-satellite era. e, Satellite records of annual mean ice sheet surface (skin) temperature for 1982 to 2021 from radiation data in the CLARA-A2.1 record processed by OSISAF2 over both ice sheets. Earth observation data allows us to generalize over the vast size and spatially varying trends of the ice sheets, where there is generally poor coverage of in situ data. Individual weather stations indicate warming trends in air temperatures over both ice sheets of ~0.61 °C per decade at the South Pole and ~1.7 °C per decade at Greenland coastal stations. Illustration by Jagoba Malumbres-Olarte

The latter surface temperature plot is not the same as the Copernicus 2m air temperature which is based on the ERA5 reanalysis (so a blending of computer model with observations from satellites, weather stations, balloons, ships, planes etc). In our paper we wanted to focus on the contribution that satellite data has brought as we simply have so few direct in situ observations, so we used skin or surface temperature which is measured from satellites. It’s a somewhat theoretical construct, imagine a very thin surface (hence skin) layer, where incoming and outgoing energy are summed up to give a temperature. This is calculated over both ice sheets and sea surface by our colleagues in the satellite group at DMI and this is the dataset we used here. Their results which stretch back to the 1980s show a slow upward trend in Antarctica and a steeper change in Greenland, the record stopped in 2021 in our paper but it actually shows an upward increase since and that’s also borne out by the Copernicus results. In climate and weather models we in fact first calculate the skin temperature and then back interpolate to 2m temperature, so the two are very closely related.

To check that the satellite skin temperature record was accurate, I also looked at some of the longer in situ records, the South pole station for example has a long record and shows a small increasing trend over the last 30 years or so (which also may be attributable to natural causes, it is hard to pick out the global warming trend). Analysis of the record also shows that it is largely due to decreasing cold extremes rather than necessarily higher warm extremes. Again, a pattern we also observe in the Arctic.

Shallow snow cores drilled near Wasa, the clear layers are refrozen surface melt that has percolated into the snow below the surface. I was genuinely not expecting to see these, and it’s not always captured in the satellite record either, so we clearly have work to do to explain some of these findings.

The analogy is not exact. As a continent, Antarctica is much further south than Greenland is to the north and it is much more insulated from warming by the circumpolar ocean than the Greenland ice sheet, sticking out in the middle of the Atlantic is. In a very real sense then, geography is destiny. Surface melt, which is also not nearly as common here in Antarctica mostly refreezes in the snowpack, whereas in the lower parts of Greenland it generally runs off and contributes directly to sea level rise. That has not yet become a major process in Antarctica, it’s still colder here and there is less surface melt for now, although from our own observations in the field, much more than I’d expected. Surface melt is definitely something we need to keep an eye on and some of our observations show how tricky that is, especially given disagreements between satellite sensors on this point .

But these are all details, the point is that Antarctica is also part of the global climate system and the same processes we’ve been observing for more than three decades in Greenland are now also starting to become apparent here too.

In one other respect Antarctica is becoming more similar to Greenland – it is becoming more contested. The Treaty that has governed Antarctica is vulnerable and subject to the same weakening of the global order that is now playing out in the North.

Let’s hope that geopolitics can settle down soon so that we can start to tackle the more serious and longer term crises coming down the line.

Lifted with thanks from Mackay Cartoons

*I’m not sure “highlights” is quite the right word either – maybe “lowlights” would be better, but then it also starts to sound like a report on hairstyles…

#Antarctica #climate #climateChange #environment #globalWarming #Greenland #GreenlandIceSheet #iceSheet #Science

Short cylindrical snow cores standing on end with clear ice layers visible in the sun
earthlingappassionato
2026-01-12

What Greenland’s Ancient Past Reveals about Its Fragile Future

The collapse of the world’s second-largest ice sheet would drown cities worldwide. Is that ice more vulnerable than we know?

July 2025 issue

scientificamerican.com/article


Expedition members Caleb Walcott-George and Arnar Pall Gíslason use a hand drill to pull rock cores out of an outcropping, called a nunatak on the Greenland ice sheet in May 2024. The samples they extract could help solve a much larger climate puzzle: When was the last time that Greenland was green? Jeffery DelViscio
2025-12-24

Parker et al provide a revised model of the ice sheet margin retreat of the Ross Sea sector of Antarctica. They show there was a rapid retreat of ice shelf between about 6900 and 5400 years ago.

#Antarctica #ClimateChange #Paleoclimate #IceSheet

doi.org/10.1038/s41467-025-654

2025-12-18

Also on the #iQ2300 expedition and posting in the fediverse is @Mercerraa - an early #FF for more #Antarctic #FieldPhotos

pixelfed.social/p/IceClimate/9
IceClimate@pixelfed.social - Wasa station. After a morning of safety training and snow scooter training, we unpacked and I took our snow optical sensors for a walk to test the surface snow grain sizes. All present and correct.
A good view from the moraine over the station and the vast whiteness of the #iceSheet beyond.
#iQ2300 #Antarctica #FieldworkPhoto #OceanIceEU #PRECISEnnf

2025-12-18
Wasa station. After a morning of safety training and snow scooter training, we unpacked and I took our snow optical sensors for a walk to test the surface snow grain sizes. All present and correct.
A good view from the moraine over the station and the vast whiteness of the #iceSheet beyond.
#iQ2300 #Antarctica #FieldworkPhoto #OceanIceEU #PRECISEnnf
2025-08-06

Next week our ECR group are starting a #MachineLearning sprint to speed up the development of our new #IceSheet surface mass budget emulation models.

I'm looking for hints, ideas tips and inspiration to help smooth and accelerate the process.

If you're used to working in #Sprint mode, what in your opinion makes it work or otherwise hinders it?

What can I as supervisor do to make it run better?
And how should we celebrate it's conclusion?

Also, should me do an #AMA on the process?

#ClimateScience #IceSheets #Greenland #Antarctica

2025-08-02

@Snoro

These happenings remind me strongly of a gripping novel I once read, making me shiver and think about my own consuming of resources:
The Sands of Sarasvati (Sarasvatin hiekkaa), in German Die Schmelze (The Melting)
by Risto Isomäki, scientific editor, environmental activist and author.

The novel is about scientists discovering huge lakes and rivers underneath and in the #Greenland #icesheet threatening to break loose.
If one wants to get the feeling how global #ClimateCatastrophe is threatening the earthly world as we know it now this is a strongly recommended read.

goodreads.com/book/show/353951

Charring Auhcharring58
2025-07-28

In Moulin

: 2008

Photo by Michael Brown

Giant holes called "moulins" form when meltwater flows into cracks in the Greentand .

#JamesBalog In Moulin

#Greenland: 2008

Photo by Michael Brown

Giant holes called "moulins" form when meltwater flows into cracks in the Greentand #IceSheet.
Norbert_R 🐘:mastodon:🦣norbert_renner
2025-07-19


The Skeptics Guide #1045 - Jul 19 2025

Quickie with Bob: Weird ; News Items: Voyager Brought Back to , Space , Global Temperature and Melting, @Robots Learn Physical Tasks 60 Times Faster, Most Powerful Solar ; Your Questions and E-mails: EV Charging, Off the Hook; or Fiction

Webseite der Episode: theskepticsguide.org/podcast/s

Mediendatei: traffic.libsyn.com/secure/skep

💧🌏 Greg CocksGregCocks@techhub.social
2025-07-02

Glacial Landforms And Rock Types [In Puget Sound Area, Washington State, As Seen With LiDAR]
--
wa100.dnr.wa.gov/puget-lowland <-- shared technical article
--
[my old stomping grounds as an engineering geologist, back when the PSLC first came out with its then ‘as if by magic’ LiDAR products around the Puget Sound…]
#geology #landform #geomorphometry #GIS #spatial #mapping #geomorphology #glacial #glacier #LiDAR #engineeringgeology #remotesensing #Seattle #PugetSound #WashingtonState #deposition #rock #sediments #till #water #hydrology #hydrography #melting #outwash #moraine #erratic #striation #boulder #icesheet #kettle #lake #WADNR

2025-06-25

If I didn't have 2 papers to (re)submit and two reports due at the ECMWF and ESA, I would write a quick blog post on how interesting it is that our modelled melt over the #Greenland #IceSheet on the @polarportal and the satellite derived melt areas almost but don't quite match, and why that might be...

fediscience.org/@polarportal/1

Client Info

Server: https://mastodon.social
Version: 2025.07
Repository: https://github.com/cyevgeniy/lmst