This article examines the parallel yet divergent histories of Indiaʼs and Chinaʼs Antarctic programmes, exploring their geopolitical, scientific, and cultural dimensions. Both nations, initially excluded from the Western-dominated Antarctic Treaty System (ATS), joined in the 1980s, marking a shift in their approach to the southern polar region. India, driven by post-colonial solidarity and environmental concerns, has focused on scientific research and conservation, while China has expanded its activities to include resource extraction and satellite surveillance, aligning with Russia to influence ATS policies. Both countries have leveraged their Antarctic presence to reinforce civilisational narratives—Indiaʼs Akhand Bharat and Chinaʼs tian xia—extending their cultural and geopolitical spheres. This article highlights their shared ambivalence towards ATS governance, their evolving strategies, and the role of Antarctica in their broader worldmaking projects. It argues that understanding these intertwined histories is crucial for addressing the conceptual clash between Global North-led environmental restrictions and Global South approaches to common resources, with implications for global climate and environmental governance.

We present a new 1:500 000 geological map of Alexander Island of West Antarctica. The map, combined with recent detrital zircon analysis, defines an updated chronostratigraphy for the Fossil Bluff Group, a Late Jurassic–Cretaceous forearc succession > 8 km in thickness that represents one of the most complete forearc successions globally. The forearc succession overlies and is in faulted contact with the LeMay Group, a late Permian basement accretionary complex that forms part of an extensive array of late Permian accretionary complexes in West Gondwana. The LeMay Group is intruded and overlain by a succession of Late Cretaceous–Palaeogene intermediate to silicic volcanic rocks and granitoid plutons. The uppermost unit on Alexander Island is an episode of Neogene to Quaternary basaltic volcanism associated with ridge-trench collisions and slab window development.

Monitoring snow depth in Antarctica is essential for understanding permafrost dynamics and soil thermal regimes. This study assesses the performance of low-cost, high-resolution, autocleaning ultrasonic sensors (MB7574-SCXL-Maxsonar-WRST7), powered by lithium D-type battery Geoprecision-Box dataloggers, in the South Shetland Islands. Traditional methods for estimating snow thickness, such as air temperature sensors in snow stakes, are economical but involve high maintenance costs and various complexities. To address these issues, we deployed ultrasonic sensors across 12 stations on Livingston and Deception islands from early 2023 to early 2024. Located at altitudes from 15 to 274 m above sea level and with varying wind exposures, these devices demonstrated notable durability and reliability, with only one sensor failure occurring due to structural damage. Data processing involved using an R script to filter out noise, and this process provided accurate hourly snow-depth measurements and revealed significant spatial and altitudinal variability, with depths ranging from 20 to 110 cm. Snow accumulation began in April and peaked in August and October, with major snowfall events contributing temporarily to snow depth but not to long-term accumulation. Our findings suggest that these sensors, as low-cost alternatives, could be integrated into networks such as the Global Terrestrial Network for Permafrost (GTN-P), supporting climate and permafrost studies.

This article explores the evolution of US policy on Antarctica, focusing on its legal, environmental and geopolitical aspects. It aims to identify changing US priorities in this regard. The Antarctic Treaty System (ATS) governs the region, emphasizing peace, scientific cooperation and environmental protection. The USA has issued four major memoranda on Antarctica in 1982, 1994, 2020 and 2024. This article highlights growing geopolitical competition, particularly with China and Russia. China frames Antarctica as essential to its global rise, using dual-purpose technologies that blur the line between science and strategic military interests. Similarly, Russia’s activities in the region raise concerns about potential violations of the ATS’s peaceful purpose mandate. The USA maintains its leadership in Antarctic diplomacy, advocating for environmental preservation and scientific cooperation. This article concludes by emphasizing the need for international collaboration to address climate change, resource exploitation and rising strategic tensions, ensuring Antarctica remains a region dedicated to peace and science.

The polar regions are famous for being inhospitable, difficult to access, and one of the final frontiers for exploration. The late 19th and early 20th centuries were filled with explorers seeking the achievement of being the first person to the Pole. These harrowing stories have action and adventure but lack a critical component: women. Women historically have not played a primary role in polar research or exploration. Many barriers to access existed such as prejudice, lack of education opportunity, and physical restrictions. Today, women have better access to the Antarctic and Arctic for research and research support but still face barriers to equitable participation. A “boys club” environment in stations can lead to women being excluded or subjected to sexual harassment. Despite this, the addition of women is shown to improve team dynamics, morale, and the culture within research stations. Women’s representation in polar research is better today than it’s ever been, yet there is still improvement being made for the future.

Microplastic release in Antarctica is an issue of increasing concern, despite the limited human presence in the region. This study estimates the annual release of microplastics from the wastewaters of scientific facilities through the use of personal care products and laundering. Furthermore, it analyses the most cost-efficient policy interventions to target this pollution. The study has estimated a potential release of 238 kg per year, which is negligible on a continental scale but could have substantial local environmental impacts. A comprehensive cost-efficiency analysis demonstrates that microplastic release can be effectively mitigated through low-cost preventative measures, such as installing washing machine filters and banning hygiene products containing microbeads. Furthermore, the implementation of wastewater treatment systems is suggested as a crucial and long-term cost-effective solution for treating wastewater effluent and removing other pollutants from the Antarctic region. These results provide a framework to inform policy decisions on microplastic release in Antarctica and lay the foundation for improved environmental protection strategies in this sensitive region.

If life ever existed on Mars, it may have developed survival strategies similar to those adopted by extremophiles living in terrestrial Martian analogs, such as the cryptoendolithic communities found in the rocky substrates of the McMurdo Dry Valleys or other ice-free areas of continental Antarctica. Nearly thirty years of research on these super-adapted organisms laid the foundation for the CRYPTOMARS project, which aims to disclose the genomic and phenotypic features allowing these microbial communities to withstand specific physico-chemical stresses that may be encountered on the Red Planet. This information will provide tools to outline, in terms of diversity and competences, a putative microbial community able to survive, adapt or even perpetuate under early or present Martian conditions. The project and the background information are here presented.

Seabirds play an important role as top consumers in the food web and can be used as biomonitors for exposure to pollutants. Erythrocyte nuclear abnormalities (ENAs) represent one of the most important ways to detect genomic damage associated with environmental degradation and pollution. This study investigates the number of ENAs in three populations of two species of Leucocarbo shags. Blood samples from the Antarctic shag (Leucocarbo bransfieldensis) breeding on the Antarctic Peninsula and the South Shetland Islands and the South Georgia shag (Leucocarbo georgianus) breeding on the South Orkney Islands were analysed. The results revealed evidence of genomic damage in all individuals, with a mean number of ENAs of 26.54 and 43.51/10 000 red blood cells for Antarctic and South Georgia shags, respectively. Thus, the shags from the Orkney Islands showed a higher number of erythrocyte abnormalities, whereas no significant differences were observed among shag populations across the Antarctic Peninsula and South Shetland Islands. These results suggest that, in the northern part of the region, shags might be more exposed to pollutants. They also provide the first reference values for cytogenetic damage in this species and establish a critical baseline for future biomonitoring efforts.

The evolution of the temperature and mass balance of first-year (FYI: Site S1) and second-year (SYI: Site S2) land-fast sea ice (LFSI) in May–November were investigated using high-resolution thermistor-string-based ice mass balance buoys, borehole measurements and a numerical sea ice model. In May, the growth rate of a 0.55 m FYI ice floe (9.2 mm day−1) was twice that of 1.08 m SYI (4.7 mm day−1) in snow-free conditions. After snow accumulation on 10 June, the growth slowed down and both reached 3.5 mm day−1 by 20 July. The observed/modelled ice thicknesses were 1.38/1.47 m for S1 (26 November) and 1.70/1.84 m for S2 (30 November). The correlation coefficients between the modelled and observed average ice temperature profiles were 0.8(vertical)/0.9(temporal) for S1 and 0.89/0.97 for S2. SYI had a higher winter cold content (32.78 MJ m−2) than FYI (21.01 MJ m−2). The modelled and observed snow depths were comparable when 50% ERA5 precipitation was used as the forcing. Snow–ice and superimposed ice formation were most sensitive to the precipitation pattern, followed by the initial snow depth and initial ice thickness. The net ice growth of both FYI and SYI were inversely related to the initial ice thickness and snow depth.

We analyse seismic time series collected during experimental campaigns in the area of the David Glacier, Victoria Land, Antarctica, between 2003 and 2016. We observe hundreds of repeating seismic events, characterized by highly correlated waveforms (cross-correlation > 0.95), which mainly occur in the grounding zone, i.e. the region where the ice transitions from grounded ice sheet to freely floating ice shelf. The joint analysis of seismic events and observed local tidal measurements suggests that seismicity is not only triggered by a regular, periodic driver such as the ocean tides but also more likely by transient pulses. We consider potential environmental processes and their impact on the coupling between the glacier flow and the bedrock brittle failure. Among the environmental variables examined, our findings suggest that clustered and repeated seismic events may be related to transient episodes of ice-mass discharge correlated to a change in the subglacial hydrographic system that originates upstream of the glacier, lubricating the interface with the bedrock. This hypothesis is supported by the gravity variation observations provided by the GRACE satellite mission, which observed mass variations during periods characterized by seismic clustering.

In the coming decades, Antarctica will face a range of challenges linked to transnational issues such as climate change, plastics pollution and geopolitical tension. Such challenges make it increasingly important for the Antarctic sector to ensure that there is broad public support for the ongoing political and environmental stewardship of the southern polar region. Initiatives such as the 2032–2033 International Polar Year offer a unique opportunity to enhance public knowledge of and investment in Antarctic research, but little is currently known about how well-suited the Antarctic sector is to the work of public engagement. In this paper, we present the results of an exploratory survey (n = 76) conducted in 2022–2023 to examine the Antarctic sector’s capacity to engage with the public. We find that, while public engagement work is certainly happening in the Antarctic sector, it is often ad hoc and under-resourced, and the skillset associated with engagement work is commonly undervalued. In order to capitalize on the opportunities presented by the next International Polar Year, we recommend that the organizations within the Antarctic sector collaborate on a joint public engagement strategy.

Polar ice develops anisotropic crystal orientation fabrics under deformation, yet ice is mostly modelled as an isotropic fluid. We present three-dimensional simulations of the crystal orientation fabric of Derwael Ice Rise including the surrounding ice shelf using a crystal orientation tensor evolution equation corresponding to a fixed velocity field. We use a semi-Lagrangian numerical method that constrains the degree of crystal orientation evolution to solve the equations in complex flow areas. We perform four simulations based on previous studies, altering the rate of evolution of the crystal fabric anisotropy and its dependence on a combination of the strain rate and deviatoric stress tensors. We provide a framework for comparison with radar observations of the fabric anisotropy, outlining areas where the assumption of one vertical eigenvector may not hold and provide resulting errors in measured eigenvalues. We recognise the areas of high horizontal divergence at the ends of the flow divide as important areas to make comparisons with observations. Here, poorly constrained model parameters result in the largest difference in fabric type. These results are important in the planning of future campaigns for gathering data to constrain model parameters and as a link between observations and computationally efficient, simplified models of anisotropy.

One century ago, US Secretary of State Charles Evan Hughes made the first official statement regarding US policy toward Antarctica by declaring it would not recognise sovereignty in areas that could not actually be settled. The Hughes Doctrine formalised US opposition to countries dividing Antarctica into sovereign territory, a doctrine that has become the bedrock upon which subsequent US decisions toward the region were built. This paper gives a broad overview of the development of US policy toward Antarctica, starting with the Hughes Doctrine, including the period when the United States secretly considered making its own claim to sovereign territory before deciding to champion then maintain the multilateral, sovereign-free region based on the Antarctic Treaty in order to achieve its national goals. This paper also reviews how the policies are working today and considers the significant challenges and costs the United States would incur if it altered its century-old policy toward Antarctica.

Cryoconite holes are supraglacial depressions containing water and microbe-mineral aggregates. Their autotrophic component plays a central role in reducing the albedo of glaciers and could contribute to sustaining the cryoconite food web. However, knowledge of its diversity is still limited, especially in Antarctica. Moreover, the study of cryoconite microalgae is challenging due to the limitations of molecular approaches, such as incomplete genetic databases and the semiquantitative nature of the data. Furthermore, it is equally difficult to examine the development of microalgae in sediment by using standard counting methods for water-living organisms. By using an adaptation of the high-speed density gradient centrifugation method, we provide a comprehensive description of the phenotypic characteristics, abundance and community structure of microalgae and Cyanobacteria in different cryoconite holes located in different glaciers of Northern Victoria Land, East Antarctica. We described 36 morphotypes belonging to Cyanobacteria, green algae and diatoms, revealing that cryoconite holes encompass a remarkably high diversity of photoautotrophs. The adapted protocol enabled the application of a standard microscopic approach, which provided crucial and comparable information on morphological characteristics, biovolume and community organization from a unique environment. The study poses the basis for the taxonomy of photoautotrophs as well as their diversity and distribution in cryoconite habitats.

Antarctic terrestrial ecosystems, covering less than 1% of the continent, are under increasing anthropogenic threats, particularly from climate change and tourism. This study focuses on the impact of human trampling on soil microbial communities in Barrientos Island (South Shetlands archipelago), a frequently visited location. Soil samples were collected within and at the edge of two established paths representing varying levels of human disturbance. Physical and chemical analyses revealed significant differences between the paths, potentially creating anaerobic conditions favorable for specific microbial taxa. Thus, microbial communities also differed between the paths. Aerobic heterotrophic taxa were dominant in the less disturbed path, while anaerobic taxa such as Bacteroidetes vadinHA17 thrived in the more compacted path. Although alpha diversity indices did not differ, beta diversity analyses showed notable distinctions, particularly between the paths rather than trampled and untrampled areas. These findings suggest that microbial communities may recover following the stop of human activity, but also that indigenous microbial communities or other overlooked factors may be influencing the recovery potential. This study thus offers a starting point for similar research, as it highlights the need for further investigation to determine whether human trampling or other environmental factors are primarily responsible for these differences.