Iceberg A23a continues to break apart in the southern Atlantic Ocean, near the island of South Georgia.

We have a new preprint out reviewing the monitoring & detection of Svalbard surging glaciers: eartharxiv.org/repository/v... We also compiled a new database of Svalbard's surge-type glaciers: zenodo.org/records/1524... @dannipearce.bsky.social @hazlovell.bsky.social @adrianluckman.bsky.social

Check out this time-lapse video of waves eroding an ice front from an experiment conducted in our cryogenic wave tank at the University of Wisconsin-Madison. The tank is housed in a walk-in freezer, and the waves are precisely controlled. This video captures about an hour of wave erosion.

In case you were wondering... Iceberg A23a seen cruising around South Georgia today by Meteosat 12. The old berg still has an area of 2,846 sq km.

I hope everyone on this website thinks very carefully about this graph and then considers whether or not they need to reorder their priorities at all.

Jakobshavn Isbrae (Ilulisat Glacier) produces 10% of Greenland's icebergs (Wikipedia). Ten years of @esa.int Copernicus #Sentinel-1 SAR data shows ice pouring into Baffin Bay. Winter advance and summer retreat of the ice front show how calving is controlled by seasonal freeze-up of fjord ice melange

Sentinel-1 has finally got a clear view of iceberg A23a (13/6/25). The berg is much diminished as it skirts around South Georgia. And the US National Ice Center has updated its stats: A23a is now only the world's second biggest berg at 829.79 sqNM, or 2846,11 sqKM.

📣 PhD position on #WorldSaltmarshDay! 🌱 👉Develop and deploy open-source sensors to measure #biophysical properties to predict #coastal #wetland #restoration success @ Swansea Uni + 3-month placement with Welsh Gov. Plz share! 🙏 www.swansea.ac.uk/postgraduate...

Nested glacier surges! This is Liestolbreen in Svalbard, surging into Nathorstbreen (which itself surged from 2008), and then being surged into by Doktorbreen. All brought to you by the magic of Sentinel-1 SAR

The movement of iceberg A23a over the past seven days. It's moved about 80km to the southeast of the position where it grounded off the coast of South Georgia in early March. Zoomed in animation from Meteosat-12.

With days shortening at South Georgia (it's about 8 hours from sunrise to sunset), optical satellite coverage in the region is getting more restricted. Not so for Meteosat, which images the Europe/Africa hemisphere regardless of season. Hence we get a few views of iceberg A23a. Still grounded.

There was a spectacular view of iceberg A23a on 3 May. Clear skies over the berg and South Georgia. By my measurement, A23a is no longer the world's biggest iceberg. At ~2850 sq km, it's now bested by D15a - but only just. The US National Ice Center will be the final judge on the matter.

The journey of Iceberg A23a (largest, oldest, 'living' berg) since the beginning of 2024, as seen by NASA MODIS, including its five-month pirouette on the Taylor Column, short embrace by the pack ice in August, grounding on South Georgia's shelf in April, and baby calf. Watch this space for updates!

Large fractures continue to open up at the grounding line of Thwaites Glacier Eastern Ice Shelf. Animation contains @copernicusland.bsky.social #Sentinel-1C data alongside 1A and 1B

US National Ice Center formally catalogues A23c, the big off-cut from grounded behemoth A23a. Daughter berg is ~130km² - or 2x Manhattan Island. A23a (~3,100km²) only needs to lose another ~30km² to hand "World's Biggest Iceberg" title to D15a (~3,070km²) in Amery Sea.

A big chunk has broken away from iceberg A23a, currently grounded at South Georgia. I calculate ~110 sq km. Looks to have fractured sometime on 11/12 April. It will get a US National Ice Center designation. It should be A23c, unless I'm mistaken.

Kronebreen is one of the fastest flowing glaciers in Svalbard. Ten years of @esa.int #Sentinel-1 data shows us both the annual advance/retreat cycle characteristic of melt-undercut calving in a seasonally warmed fjord, and the long-term retreat caused by climate warming. Email me for hi-res version

Fantastic new animation from ESA featuring CryoSat-2 & Sentinel-1 animations, highlighting our Nature-Comms paper "The influence of subglacial lake discharge on Thwaites Glacier ice-shelf melting and grounding-line retreat" www.nature.com/articles/s41... led by Noel Gourmelan: youtu.be/vRMeiMsQkBE

So exciting! Sentinel-1C (launched December) is finally delivering data to users and we can get back to exploring 6-day-repeat interferometry and feature-tracking such as this lovely new velocity map of Helheim Glacier in East Greenland. Nice one Copernicus!

You don't need to be a seismologist to look at this figure and understand the huge forces that ripped through Myanmar on March 28. The M7.7 quake ruptured fully 500km of the Sagaing Fault, moving its western flank north, with >3m of slip at the surface. Data from EU Sentinel satellites.

Update on Thwaites Glacier Eastern Ice Shelf from Copernicus Sentinel-1 SAR. Downloadable version here: aluckman4.wixsite.com/ade-s-world-...

Iceberg A23a pictured from the ISS. The space station is almost as far south as it can reach here (51.5° S, 49.0° W - altitude of 422km). Picture taken on 14 March, so the berg had been grounded at South Georgia for a fortnight by this time.

As polar night ends and sunlight begins to return to Longyearbyen, lets see how the Svalbard seasons progressed last year - from ice-locked fjords in March, through to the first snows of October. Thanks to NASA MODIS via GIBS. Download at full resolution here: aluckman4.wixsite.com/ade-s-world-...

Europe had its least snowy winter (Dec-Feb) in over 50 years. #ThisIsFine

The extent of sea ice around the world continues to remain the smallest in our satellite observation history for this time of year... More graphs at zacklabe.com/global-sea-i.... Data from @nsidc.bsky.social.

The world's largest iceberg, A23a, appears to have grounded close to South Georgia. We've been monitoring and mapping this berg for many years now and we're watching closely to see what it might do next! These maps show its route since 1986 and the latest position to the SW of South Georgia ❄️🐧 1/3

Rain in the northernmost city on Earth. This month temperatures have been almost always above normal. The Arctic is becoming totally unrecognisable. And in the meantime #BP and #Equinor are doubling down on fossil fuels. Profits over people. Profits over a liveable Earth.

Pisgana West (Adamello, IT) 1990 | 2021 Remember the 1990s? ⌚️❄️ Seems so far away from a glaciological point of view! 😱 And the most recent pic here was taken before the recent record-breaking heatwaves which wiped out 10% of Alpine ice in just 2 years! 🔥 📷 Servizio Glaciologico Lombardo

Pine Island Glacier accounts for a large proportion of recent Antarctic ice loss. This 7.5 year animation from Sentinel-1 shows the weakening of the lateral margins and the stochastic nature of the calving process. Grab a full-screen version here: aluckman4.wixsite.com/ade-s-world-...

Americans proposed that Ukraine concede half of the profits from its mineral rights in perpetuity... in exchange for essentially nothing. This is not a monetary proposition, let alone a "deal," but rather the demand that Ukraine become a permanent American colony. snyder.substack.com/p/recoup-the...

In their latest update, the GLAMBIE Team show that the pace of glacier melting has increased by 36%. Community assessments are vital as they give non-experts the confidence to act on their findings. www.bbc.co.uk/news/article...

Amid the majestic beauty of nature and the noble pursuit of science, the toilet tent can start to present pressing logistical issues... Today's ICEWORLD is all about a #polarscience investigation into ice shelf rifts and 'suture' ice on the Larsen C Ice Shelf ⬇️ podcasts.apple.com/gb/podcast/s...

The idea of renaming "Greenland" to "Red, White and Blueland" must have come from our 2020 Science paper where we (Ben Smith and 14 others) used NASA's ICESat and ICESat-2 laser altimetry to show how much the ice sheet surface went up or down in 16 years.

A new iceberg, ~30x14 km in size, recently calved from the southern end of the George VI Ice Shelf. It's called A84 and is already making quite an impact, bumping into the Stange Ice Shelf over the weekend! These Copernicus Sentinel-1 images from Polar View show the new berg over the last few days.

Sentinel-1 SAR data from the EU Copernicus program can be used to measure ice surface speed. This decade long time-series of mean annual speeds shows the ebb and flow of glacier surges around Svalbard. Download a full-resolution version here: aluckman4.wixsite.com/ade-s-world-...

This is by far the best modelling attempt of the Alpine Ice Field during the LGM (35-18 ka)! 🧊⌚ Thinner ice than previous attempts and better fit to the trimlines ❄️ Must read! www.nature.com/articles/s41... Don't miss the YT vids www.youtube.com/watch?v=wJ5-... Congrats @legertancrede.bsky.social!

Thwaites Glacier calves kilometre-scale icebergs every few weeks. Here's an animation of the process from Sentinel-1. For a longer and higher-resolution version, have a look here: aluckman4.wixsite.com/ade-s-world-...

Applications are OPEN for our tuition-FREE, multi-day expeditions blending science, art, and backcountry travel! Open to high school girls* (ages 16-18 on June 1, 2025). Visit inspiringgirls.org for more details. Share to help spread the word - we can't wait to adventure! ♥️ #InspiringGirls

Sorry - a not so very good Sunday ice update. #Arctic sea ice extent is easily the *lowest* on record to kick off a new year (JAXA data)... 🌊 • about 610,000 km² below the 2010s mean • about 2,160,000 km² below the 1980s mean Additional long-term sea ice graphs: zacklabe.com/arctic-sea-i...

Two Svalbard glacier surges (Arnesenbreen and Nordsysslebreen) in one frame, as seen by Sentinel-1. Hi-res video available here: aluckman4.wixsite.com/ade-s-world-...

A glacier that is far from being in peak condition, it's still beautiful #EarthArt. The ogive stripes are still really clear on the #MerDeGlace even though the front looks like it's becoming debris-covered.

To round of the year my wonderful friend @helen-amanda.bsky.social has been awarded the prestigious Seligmann Crystal by the International Glaciology Society !!!! What fabulous news !!! 🤩🎊🎉🥂🥳🛰❄️🧊🧪🍾🎆🌍 www.igsoc.org/about/awards...

Just updated my visualization of change in land ice mass as observed by GRACE(-FO) satellite in #Antarctica (left) and #Greenland (right) 🧊📉🌊 Methods can be found at climate.nasa.gov/vital-signs/.... My graphic can also be downloaded: zacklabe.com/arctic-sea-i....

Animation of Denman Glacier in East Antarctica from Sentinel-1 SAR. If you can't make out the fascinating surface movement at this scale, have a look at the full resolution version here aluckman4.wixsite.com/ade-s-world-...

A23a has finally escaped the vortex! 🏊‍♀️🌀 The biggest iceberg in the world is on the move again after a casual half-year sabbatical spent spinning in circles. Our @magic.bas.ac.uk colleagues have illustrated A23's super circuitous 2024 journey via satellite imagery ⬇️ www.bas.ac.uk/media-post/w...

Congratulations to my collaborator and friend, Laurie Padman @lpadman.bsky.social, on being named an AGU Fellow. Well deserved 🎉🥂

This is the surge of Hamarbreen and Sefstrombreen, a pair of glaciers in Svalbard, as seen by #Sentinel-1. There had been interesting dynamic activity in the upper region (Hamarbreen) for some years. The speed with which the lower surge was triggered is impressive.

Is this the final death throes of the Thwaites Eastern Ice Shelf? Let's hope that tomorrow's launch of #Sentinel-1C is successful and polar ice monitoring can get even better!