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Reposted by Adrian Luckman

cira-csu.bsky.social @cira-csu.bsky.social · 22d

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

Reposted by Adrian Luckman

Will Harcourt @willharcourt.bsky.social · Aug 22

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

Surging glaciers in Svalbard: Observing their distribution, characteristics and evolution

eartharxiv.org

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Luke Zoet @lzoet.bsky.social · Jul 16

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.

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · Jul 7

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.

Iceberg A23a on 7/7/25 Eumetsat/Meteosat 12

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Reposted by Adrian Luckman

Dr. Genevieve Guenther (she/they) @doctorvive.bsky.social · Jun 26

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.

Global average temperature compared
with the middle of the 20th century

+1.0°C 2010 to
present

+0.5°C
1970 to
2010

Cooler than average
-0.5°C
1880 to 1970

• Note: Data available through May 2025. Anomalies
relative to the average temperature between 1951 and 1980. • The New York Times
2020

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Adrian Luckman @adrianluckman.bsky.social · Jun 26

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

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · Jun 15

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.

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Reposted by Adrian Luckman

Cai Ladd @cailadd.bsky.social · Jun 11

📣 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...

Biosciences (Restoration Ecology): Fully Funded PhD Studentship in Restoring Intertidal Systems using Electronics (RS851) - Swansea UniversityMenu

We offer a wide range of funded and fully funded research scholarships in all subject areas. Explore your options and apply now.

www.swansea.ac.uk

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Adrian Luckman @adrianluckman.bsky.social · Jun 10

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

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · Jun 4

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.

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · May 30

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.

Meteosat view of South Georgia and iceberg A23a. 30/5/25

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · May 6

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.

Iceberg A23a on 3 May. Copernicus / Sentinel-3

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Adrian Luckman @adrianluckman.bsky.social · May 2

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!

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Adrian Luckman @adrianluckman.bsky.social · May 1

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

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · Apr 22

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.

A23a and A23c pictured off South Georgia on 22/4/25 Nasa Worldview Modis

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · Apr 16

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.

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Adrian Luckman @adrianluckman.bsky.social · Apr 7

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

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Adrian Luckman @adrianluckman.bsky.social · Apr 3

So sorry for the typo Noel Gourmelen!

Adrian Luckman @adrianluckman.bsky.social · Apr 3

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

How subglacial lakes threaten Antarctic Ice Sheet stability

YouTube video by European Space Agency, ESA

youtu.be

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Adrian Luckman @adrianluckman.bsky.social · Apr 3

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!

Map depicting Helheim Glacier comprised of grey-scale backscatter image overlain by colours from blue to pink denoting ice surface velocity from 2 to 30 meters per day during the period 25th to 31st March 2025

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · Apr 2

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.

NASA/JPL/Caltech/ARIA/Copernicus Product. POC: R Zinke/G Bato/C Speed/E Fielding.

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Adrian Luckman @adrianluckman.bsky.social · Mar 31

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

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Reposted by Adrian Luckman

Jonathan Amos @jcdamos.bsky.social · Mar 24

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.

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Adrian Luckman @adrianluckman.bsky.social · Mar 17

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-...

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Reposted by Adrian Luckman

Climatologist49 @climatologist49.bsky.social · Mar 9

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

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