As the year comes to a close we’d like to thank our incredible supporters, researchers, and partners for helping to advance crucial Antarctic science. We wish you all a Merry Christmas and a Happy New Year, and we look forward to continuing our work in the year ahead!🐧❄️🎁

#Subglacial sediment : key to reconstruction of #Cenozoic topography and #paleoenvironment 🇦🇶

The first flight to our deep-field scientific drilling site at Crary Ice Rise has departed Ross Island. The approximately 700km journey over the Ross Ice Shelf took around 2 hrs on a Basler. On board were our hot water drillers, most of our AIDD team, and camp staff 👉https://bit.ly/3KxwJgC

11/ Their computer modelling projects other changes in AABW such as meltwater, salinity and temperature by 2050 – “essentially an intensification of the patterns of change observed since the 1990s”, the review says.

10/ 𝗔𝗔𝗕𝗪 𝗶𝘀 𝗳𝗿𝗲𝘀𝗵𝗲𝗻𝗶𝗻𝗴. Melting ice shelves make the waters fresher and more buoyant. Another study by some of the same authors simulated the future response of the ocean to meltwater input, projecting a slowdown of the Antarctic overturning by 40% by 2050. ▶️ aappartnership.org.au/antarctic-de...

9/ 𝗔𝗔𝗕𝗪 𝗶𝘀 𝘁𝗵𝗶𝗻𝗻𝗶𝗻𝗴: since the mid-80s, at rates greater than 50 metres per decade in the deep Antarctic basins, with more rapid thinning observed closer to the sources of AABW. Contraction of AABW may lead to increased exposure of Antarctic ice shelves to warm water and further melt.

7/ So any change in AABW properties has consequences for the strength of the deep overturning circulation – and climatic patterns. We know that rapid change is already underway in the abyssal ocean. Sea ice edge 📸 Todor Iolovski/AAD

8/ 𝗔𝗔𝗕𝗪 𝗶𝘀 𝘄𝗮𝗿𝗺𝗶𝗻𝗴. Since the mid-80s, ocean heat content below 4,000m has increased at a rate of about 13 trillion watts – about equal to the global energy consumption rate by humans each year.

6/ From these regions, AABW moves into the Pacific, Indian and Atlantic Oceans, driving many of the world's significant currents. This shows the fraction of water on the seafloor that is composed of AABW (dark blue is more than 90%, depths shallower than 3,500m not shown).

5/ AABW only forms in four locations: Weddell Sea, Cape Darnley, Ross Sea and Adelie Land. ‘Sv’ is a Sverdrup, a measure of current flow rate (1 Sv = 1 million cubic metres per second). Any changes in these regions (like sea ice) may impact the 3-D structure of the global overturning circulation.

4/ To form AABW, cascades of dense water spill from the continental shelf and sink to the deep ocean: seawater freezes to form sea ice ➡️ rejects brine ➡️ dense cold salty oxygen-rich water sinks ➡️ pumps oxygen into the deep sea ➡️ ‘ventilates’ abyss Watch ▶️ vimeo.com/830053753

3/ How will this lifeline change on a warming planet? A new review in @natrevearthenviron.nature.com led by Steve Rintoul at CSIRO/AAPP examines the importance of AABW to ocean carbon and heat storage and oxygen supply to the deep sea – and the impacts of global heating. Review ▶️ rdcu.be/eTWCD

2/ Driving the pump is Antarctic Bottom Water (AABW), cold dense water that sinks from the continental shelf to the deep (dark purple) and fills 36% of the global ocean volume. The sinking of AABW is balanced by a return flow of lighter warmer water (yellow). Pic: @antarcticsciaus.bsky.social

1/ The overturning circulation is a network of ocean currents transporting heat, carbon, oxygen and nutrients around the world. At the heart of this circulatory system is the global pumphouse of #Antarctica and the Southern Ocean. Animation: NASA-SVS

Announcing “Antarctica as a Model for Global Peace”. Chapter by Bruno Arpi & I: “The resilience of the Antarctic Treaty System in the face of a changing global order“. Great working with Agenda Antártica and Konrad Adenauer Stiftung on this chapter. www.kas.de/documents/d/...

💦 "In effect, the Southern Ocean may be “sweating” more in response to climate change." — @aunz.theconversation.com ▶️ theconversation.com/storms-in-th...

Here's something those travelling to Antarctica hope they won't need. If your flight 'boomerangs' and has to turn back around, you'll be reunited with your checked-in boomerang bag.We're sharing Antarctic terms and phrases so that you too can #TalklikeanAntarctican!

Adrift like Shackleton: Robot float survives #Antarctic ice. The Argo float disappeared under the ice and survived to send back the first-ever ocean transect beneath an East Antarctic ice shelf. www.csiro.au/en/news/All/...

7/ Hats off to authors Steve Rintoul, Esmee van Wijk, Laura Herraiz-Borreguero and Madelaine Rosevear from CSIRO, AAPP, @utas.edu.au and @imas-utas.bsky.social – with support from @imos-aus.bsky.social – and the intrepid #Argo floats. @euro-argo.eu @soccomproject.bsky.social @soosocean.bsky.social

6/ This work reveals the Shackleton ice shelf is, for now, not exposed to warm water capable of melting it from below. However the Denman Glacier is and therefore more vulnerable. Its ice volume holds a potential 1.5-metre contribution to global sea level rise.

5/ That’s where floats can help, bumping their heads on the underside of ice shelves, measuring melt where it happens. Deploying an array of floats around Antarctica's continental shelf would reduce the large uncertainties in estimating future sea level rise. ▶️ theconversation.com/what-our-mis...

4/ But measuring inside ice shelf cavities is very difficult to do. Ice shelves can be hundreds of metres thick. While you can drill a hole through and lower your sensors, this is expensive and rarely done, so very few observations have been made. ▶️ aapp.shorthandstories.com/how-to-drill...

3/ Ice shelves resist the flow of continental ice to the sea. If warm ocean waters weaken the ice shelves, more ice will reach the ocean and melt, causing sea level to rise. Ocean measurements are critical to determine how much and how fast. ▶️ aapp.shorthandstories.com/opening-the-...

2/ After eight months hidden away, profiling the ocean from the seafloor to the base of the ice every five days, the Argo float survived to deliver the first-ever oceanographic transect from beneath an East Antarctic ice shelf. ▶️ aappartnership.org.au/adrift-like-...

🌊 1/ A robotic float has measured temperature and salinity from parts of the Southern Ocean never sampled before — underneath massive floating Denman and Shackleton ice shelves in East #Antarctica. New in @science.org #ScienceAdvances: www.science.org/doi/10.1126/...

Our November newsletter just went out, featuring ... Report of SCAR at 44th CCAMLR Meetings ... INSTANT workshop at CliC OSC 2026 ... SCAR at #COP30 in Belém, Brazil ... and more! ▶️ Read: mailchi.mp/scar/novembe... ▶️ Subscribe: scar.us7.list-manage.com/subscribe?u=...

The smiles say it all - they've finally made it to the ice! After an extended stay in Christchurch due to weather delays, followed by an 8hr boomerang back to Christchurch, the first of our science team have landed in Antarctica.

At @imas-utas.bsky.social @utas.edu.au, we're celebrating Antarctica Day 2025 with a symposium themed ‘Encountering Antarctica’. 🐧 www.utas.edu.au/about/events...

Happy Antarctica Day! 💙 1 December is the anniversary of the signing of the Antarctic Treaty in 1959. Australia was one of 12 original signatories to the Treaty, which established #Antarctica as a "natural reserve, devoted to peace and science".

Antarctica Day marks the anniversary of the signing of the Antarctic Treaty, setting the foundation for international collaboration in Antarctic research. SWAIS2C brings together researchers from 10 countries, dedicated to understanding how Antarctica’s ice sheets will respond in our warming world.

🌍 Happy #AntarcticaDay! 🌍 To mark the occasion, we’re delighted to announce that the call for abstracts for the 12th SCAR Open Science Conference #SCAR2026 (8-19 August 2026 in Oslo, Norway) is now open. Submit your abstracts by 28 February 2026 scar2026.org/abstracts

@antarctic.bsky.social @antarcticsciaus.bsky.social

🌏 Happy Antarctica Day! ❄️ Today we celebrate global cooperation in protecting and understanding one of Earth’s most unique and fragile environments. A huge thanks to all our researchers for driving this work forward every day. 🎥 Learn more in our new ACEAS video: www.youtube.com/watch?v=AGg3...

Happy Antarctica Day! We’ve recently updated this map to show consultative and non-consultative signatories of the Antarctic Treaty, signed on this day in 1959. The Treaty designates Antarctica a continent for peace and science. December 1st raises awareness of this global agreement and its goals.

It’s Antarctica Day! Give it up for this articulated skeleton of Thrinaxodon, an early mammal relative from 250 million years ago, found in the Transantarctic Mountains 8 years ago. This continent has an amazing fossil heritage that we’re continuing to learn more about!

MYIC drilling team landed at Dome C earlier today. We are one day behind schedule, which in the face of logistical and weather challenges of operating in Antarctica is a big WIN!! Two months ahead of us for deep drill set up and ice coring. Bring it on!!

10/ But we have choices. Under high emissions, a positive SAM continues to strengthen. Under low emissions pathways where net zero is achieved, modelling shows the SAM could stabilise by 2050 and begin returning to its historical range by 2100. (figure: @nature.com)

8/ The implications for sea-level rise are less clear. Ocean circulation changes could accelerate melt in the cavities underneath ice shelves that buttress the Antarctic ice sheet, while SAM-driven increased snowfall in some regions may offset ice mass loss. (photo: Pete Harmsen/AAD)

7/ A persistent positive SAM is expected to reduce the Southern Ocean’s ability to absorb excess carbon dioxide, warming the climate. Stronger, southward-shifted winds create upwellings that release more carbon from the deep ocean into the atmosphere. (photo: Pete Harmsen/AAD)

👏 6/ Authors from @arcsaef.bsky.social, @monashuniversity.bsky.social, @21stcenturyweather.bsky.social, BoM, @imas-utas.bsky.social, @utas.edu.au, @antarcticsciaus.bsky.social, @ccrc.bsky.social, @unimelb.bsky.social, CSIRO

5/ New review out today in @natrevearthenviron.nature.com: “The SAM is now in its most positive mean state in over 1,000 years, and a year-round positive trend in the SAM is projected to continue throughout the twenty-first century in response to increasing greenhouse gases.” Read: rdcu.be/eSGwe

4/ A positive SAM also changes the biogeochemical state of the Southern Ocean, affecting how carbon, heat and nutrients are transported and shaping the productivity of phytoplankton. (figure: Nature)

3/ A positive SAM changes the physical state of the Southern Ocean which affects sea ice, ocean circulation and the Antarctic ice sheet. (figure: Nature)

🌀 2/ The effects of the SAM connect the stratosphere to the ocean, and Antarctica to the tropics. In the Southern Ocean, it drives the Southern Westerly Winds (SWW) which drive the Antarctic Circumpolar Current, the world’s strongest current surrounding Antarctica. (figure: AntarcticGlaciers.org)

9/ “Given the importance of SAM effects on Southern Ocean circulation, carbon cycling, and Antarctic ice mass balance for future climate and sea level rise projections, it is crucial that the effects of SAM are better modelled and understood,” the review says.

🌊 1/ Meet SAM. The Southern Annular Mode (SAM) is the Southern Hemisphere’s most influential #climate driver. When the SAM enters a positive phase, the westerly winds tighten and move towards #Antarctica. When it moves into a negative phase, these winds expand back towards Australia. (figs: BoM)

Grateful to receive funding from @asfofficial.bsky.social This will greatly enhance my research on the population dynamics of the Southern Ocean seastar Glabraster antarctica! This work is fundamental to understanding #benthic #invertebrates’ response to #climatechange 🧬🇦🇶

Happy Antarctica Day! Today we celebrate 66 years of the Antarctic Treaty, an international promise to keep Antarctica a continent of peace, science, and environmental protection.