There is clear evidence that rapid warming has been fuelling significant changes in the ocean and cryosphere in the Antarctic Peninsula region. Less is known about how terrestrial biological ecosystems, particularly plants, are responding to warming and hydroclimatic change. We show that high evaporative environmental conditions and microclimate associated with topography lead to humidity-dependent evaporative effects on the oxygen isotope ratios (δ18O) of moss waters and α-cellulose in the northern Antarctic Peninsula, based on a spatial (> 400 km) isotopic survey at 14 sites over 24 days during summer 2020. The δ18O of moss waters define a water line of δ2H = 4 × δ18O + 37 for Polytrichum strictum and δ2H = 3.8 × δ18O + 38.9 for Chorisodontium aciphyllum, indicating enrichment compared to line slopes ranging from 6.7 to 8.5 for snow, standing water, previous published snapshots of moss waters and the long-term local meteoric water lines along the Antarctic Peninsula. The δ18O of moss waters negatively correlated with relative humidity (which ranged from ~50% to 100%) and not with temperature or latitude, where a higher δ18O indicates increased evaporative enrichment or dry conditions. A positive correlation between the δ18O of moss waters and α-cellulose (ρ = 0.397, P = 0.011) for P. strictum (ρ = 0.533, P = 0.007) but not C. aciphyllum suggests that the high evaporative conditions from the season imprinted on the cellulose. Lastly, we found significant positive correlations between topographic aspect (north-exposedness) and the δ18O of moss waters (ρ = 0.569, P < 0.001) and α-cellulose (ρ = 0.579, P < 0.001), indicating that irradiance on north-facing slopes promotes drier conditions and evaporative enrichment. Topographic aspect (and resulting microclimate) is an important and predictable determinant of the δ18O of moss waters and α-cellulose. This study highlights that mosses are sensitive recorders of climatic and non-climatic conditions in polar terrestrial ecosystems.

Many authors have studied the biogeography of the Southern Ocean (SO), defined its limits and proposed their division into biogeographical zones and provinces. In this work we analyse the biogeography of sea slugs in a broad sense (Mollusca, Gastropoda, Heterobranchia) in the different areas and zones of the SO below 41°S. Most of the published scientific publications, databases and technical reports where records of benthic sea slugs appear in the SO have been analysed in addition to our own records, cataloguing a total of 355 different benthic species. The following areas and zones of the SO have been considered: Antarctica (Weddell Sea, West Antarctica, Ross Sea, East Antarctica), the sub-Antarctic zone (Falkland Islands, South Georgia Island, South Orkney Islands, South Sandwich Islands, Bouvet Island, Crozet and Prince Edward islands, Kerguelen Islands, Macquarie Island), southern South America (Patagonia/Magellan), Tasmania and New Zealand (South Island). A presence/absence table for all recorded species in the different zones has been compiled, and the differences and similarities between them have been calculated using the Sorensen index. The best representation has been obtained by classifying the zones into five groups: G1 (the four Antarctic zones, South Georgia Island, South Sandwich Islands, South Orkney Islands), G2 (Kerguelen Islands, Crozet and Prince Edward islands and Macquarie Island), G3 (Falkland Islands and Patagonia/Magellan), G4 (Tasmania and New Zealand’s South Island) and G5 (Bouvet Island). In addition, the concordance between the non-hierarchical classification (K-mean) and the hierarchical classification obtained using the WARD and UPGMA cluster analysis methods has been verified. The representative and distinctive species of each of these groups are indicated. In this work, as regards benthic sea slugs, the biogeographical affinities between the Antarctic zones and some of the sub-Antarctic zones are confirmed, as well as between the fauna of these molluscs in the Patagonian/Magallan zone and the Falkland Islands, while the affinities between the other zones need further confirmation when more species records become available.

The McMurdo Dry Valleys in the Ross Sea Region of Antarctica represent a globally unique desert ecosystem where water availability is likely to change under global warming scenarios, thus influencing the distribution and abundance of biota. Using the Random Forest machine learning model, we focused on the spatial distribution of macroscopic terrestrial biota (moss, cyanobacteria, lichen, springtails and mites) in the Dry Valleys. A wetness index, explicitly driven by satellite-derived glacier surface temperatures and meltwater routing, was used along with biological survey data collected over six field seasons (2009–2014) as part of the New Zealand Terrestrial Biocomplexity Survey (n = 886 sites). Our analyses use the full extent of survey data available and include the larger Taylor, Wright and Victoria valleys, as well as data from the previously studied Miers, Marshall and Garwood valleys. The overall model accuracies were mixed (kappa statistic: 0.34% and 17.3% variance explained). However, the resulting predictive maps derived from the model and the influence of the different explanatory variables align with field observations and theoretical expectations. The models show that distance from coast was an important driver for the biota, as well as elevation and temperature. The predictive maps provide an initial model of the distribution of biota in the Dry Valleys and can guide future sampling as well as inform conservation and management strategies. Our research highlights the importance of biological survey data for use in spatial predictive modelling as well as the need to obtain representative samples from a wide range of different habitats (e.g. wet vs dry).

In 2019 we collected gravity and magnetic measurements, in conjunction with multibeam swath bathymetry and multi-channel seismic reflection profiling, to characterize the neovolcanic zone around Orca Volcano in the Central Bransfield Basin, Antarctica. New analysis of mafic dredge samples shows that the caldera is composed of rocks with a wide range of measured susceptibilities. Multi-channel seismic reflection profiles across Orca Volcano showed the presence of several reflectors under the caldera, characterized by strong amplitudes and phase-reversed polarity. Gravity and magnetic data also show coincident anomalies. Our 2D forward modelling shows that these anomalies are the result of a shallow magma accumulation zone underlain by a low-density, low-susceptibility volume. We also observe that the axial ridge to the south-west of the volcano is characterized by a narrow zone of low density and high susceptibility, consistent with a focused rift axis. To the north-east of the volcano, the potential field data show that the axial rift is left-lateral offset and is somewhat broader. An asymmetric pattern of decreasing density and susceptibility of igneous rocks across the rift is consistent with a pattern of extension that has only recently evolved into a narrow rift and the mid-ocean ridge basalt-like compositions seen in dredge samples. These results are consistent with rifting that is rapidly transitioning to seafloor spreading.

Human activity in the Antarctic is supported by a wide network of government agencies, policies, businesses and workers back home. This polar workforce is particularly important in the so-called ‘Antarctic gateway cities’, which foreground their economic and cultural connections with the far south. Rather than focusing just on the Antarctic continent as the place of work, this paper therefore takes a broader approach by turning attention to the people back home that enable Antarctic logistics, modelling, policymaking and public awareness to be executed successfully. The paper outlines a matrix for mapping polar work capacity, with Antarctic roles classified as direct or indirect and as in situ or ex situ. By bringing together stakeholders from a range of Antarctic workplaces (including local and national government, academia, tourism and local business owners and training providers) from Christchurch (New Zealand) in October 2024, a workshop event identified the key challenges facing the Antarctic sector over the coming 5 years and highlighted areas where international collaboration could help to address these challenges into the future. Key suggestions include the implementation of an overarching Antarctic strategy; training and education to improve local talent and pathways; enhanced visibility of existing skillsets; establishing exchange opportunities across the Antarctic gateway cities; and developing Antarctic identities, including through tourism opportunities.

In 1988, meteorological measurements started at the Spanish research station Juan Carlos I (JCI) on Livingston Island. A second station - Gabriel de Castilla (GdC) - was installed in 2005 on Deception Island. These long-term measurements improved our climatological understanding of the western region of the South Shetland Islands (SSI), a region that has received less attention than the more station-populated King George Island in the central SSI. Here, we present a complete climatological analysis of these stations after undertaking a full quality control process of the data. This analysis covers temperature, wind, precipitation, radiation, relative humidity and pressure, as well as trends and variability. The results show: 1) the stations along the western SSI coastline, particularly JCI, are warmer than those on the central SSI, especially in summer, 2) at GdC, winters are colder due to stagnant cold air pooling within the Deception Island caldera, 3) the importance of island orography in shaping local climatology, especially regarding wind patterns, and 4) the critical need to correct precipitation measurements for undercatchment of solid precipitation by common pluviometers. This study provides a climatological framework to support further research conducted in the region.

The Antarctic Peninsula is one of the regions in Antarctica that has experienced notable and extensively studied warming since the mid-twentieth century. Meteorological data, although limited and mostly dating back to the International Geophysical Year (1957–1958), reveal dramatic climate changes in both the Antarctic Peninsula and West Antarctica, with the Antarctic Peninsula showing the highest warming trends on the continent. One major manifestation of this warming is the increasing frequency and intensity of extreme warm events. This study utilizes temperature data from the Artigas Antarctic Scientific Base provided by National Weather Service, Uruguayan Institute of Meteorology (INUMET), which have not previously been used or quality-controlled. Data were processed and analysed, and a quality hourly database was built for the period 1 January 1998 to 11 December 2016 for the surface temperature, constructing a complete time series interpolating the data with two other nearby Antarctic stations (C.M.A. Eduardo Frei Montalva and King Sejong). Temperature presented an annual cycle with marked interannual and seasonal variability, with the cold season being the one with the highest variability and the largest anomalies, both positive and negative. No significant trend was found for the monthly mean temperature. A study of warm temperature events was conducted at three points on King George Island, defining warm events and extreme warm events as those in which the mean daily temperature was above the 90th and 99th percentile, respectively, for at least 3 consecutive days. A high frequency of occurrence was found (all years except 2015) mostly in the cold season of the year, and with large interannual variability. In turn, it was found that certain atmospheric dynamics favour the generation of these extreme warm events, and that their occurrence is higher during La Niña years. Although the majority of the extreme warm events occurred during positive phases of the Southern Annular Mode, the statistical correlations were not significant.

Deception Island is an active, caldera-forming volcano whose surveillance is critically constrained by its extreme Antarctic isolation, scarce resources and limited seasonal human access. This study addresses these challenges by presenting an innovative Global Navigation Satellite Systems (GNSS) geodetic surveillance framework specifically adapted for such a remote environment. Our approach establishes a key operational distinction between non-real-time monitoring and near-real-time surveillance via a semi-continuous wireless network. We effectively resolve the inherent trade-off between promptness and precision by applying signal enhancement methods (e.g. Kalman filtering) to maintain millimetric accuracy in deformation detection, even when utilizing the high sampling rates (1 Hz) essential for rapid assessment. The resulting model allows for the rigorous isolation of the local volcanic signal from the complex regional tectonic kinematics. Crucially, data analysis reveals recurrent 3 year cycles of inflation and deflation in the magmatic system, strongly correlated with seismicity, which validates ground deformation as a reliable volcanic precursor. The primary practical advance is the validation of a dual-term hazard forecasting system: 1) mid-term (months) forecasts based on long-term time-series analysis to facilitate safe inter-campaign operations and 2) short-term (days) forecasting during periods of unrest using ground displacement acceleration, complemented by a magma injection model to predict the spatial location of potential vent openings. This validated and technologically adjusted framework provides an optimized and transferable template for continuous geodetic surveillance in other isolated, active polar volcanoes.

The first fossil fauna to be described from the Antarctic was collected at Seymour Island in December 1892 by Captain Carl Anton Larsen and the crew of the Norwegian whaling ship Jason. Some specimens collected by Larsen’s crew were acquired by Charles Donald, the surgeon with an 1892–1893 Scottish whaling expedition from Dundee that was also operating in the vicinity of Seymour Island. Donald returned the fossils to Scotland, and they were described in two papers published by The Royal Society of Edinburgh (1894 and 1899) as, inter alia, two new species of Palaeogene bivalves and one of Cretaceous to Palaeocene age. Sadly, the described Palaeogene specimens are now lost, but one Cretaceous/Palaeocene survivor, the holotype of Lahillia larseni, has been located in the palaeontology collection of the British Geological Survey with the reference number FOR 4053. On Seymour Island, Lahillia larseni is a common species in both Upper Cretaceous and Palaeocene strata and is of particular importance as its abundance seems to have been unaffected by the end-Cretaceous extinction.

A Doppler Sonic Detection and Ranging (SODAR) wind-profiling system was deployed at Jang Bogo Station, Antarctica, during the summer of 2017. The parameters measured by the SODAR system were wind speed and direction averaged for 15 min from 30 m above the surface to 500 m aloft. Additionally, wind measurements obtained from the nearby walk-up tower and automatic weather station (AWS) were also used for additional data and comparison, respectively. The analysis and comparison used hourly average for consistency. The mean wind speed obtained from the SODAR measurement is highly correlated with those from the walk-up tower and the AWS measurements. All three measurements recorded westerlies during all strong wind events but varied during calm periods. The measurements also reveal that Jang Bogo Station experiences lower wind speeds compared to the nearest katabatic confluence region (Inexpressible Island), where the maximum airflow usually occurred. From the hourly averaged data, SODAR only detected a maximum wind speed of 18.1 m s−1. There were 238 occurrences of strong wind events equal to or above 10.8 m s−1 (Beaufort scale 6) from 10 May to 31 October 2017. These occurrences were recorded in 50 out of 175 days analysed in this study. From 10 to 12 June 2017, predominantly south-westerly-westerly winds were recorded at the surface and aloft during two strong wind events. Based on this case study, the boundary layer during calm and strong wind periods was also analysed.

Understanding the diverse pathways between science and policy is crucial for assessing the impact of research. In this context, ‘research impact’ refers to the broader societal benefits of scientific research that extend beyond traditional research evaluation metrics. Metrics of academic and scientific excellence, such as h-indexes or bibliometric analyses, often fail to capture the impact of science on policy. To investigate one aspect of how research can influence policy, and therefore probably have impact, this study analysed ice core publications from the Australian Antarctic Program. A dataset of 266 Australian-authored and/or -funded East Antarctic ice core publications was examined, revealing that 123 were cited in 284 international and Australian (domestic) policy and policy-related documents. To analyse the policy influence of the research, key information was categorized into authoring countries, institutions, research themes and the contextual use of publications by the documents. This categorization highlighted the different uses of information and interpretations of ice core publications by separate forums, with some more active compared to passive uses. The ‘Active-Passive’ spectrum developed in this study provides a framework for understanding how research is being used, and it underscores the relevance of ice core science to local Australian governance. The results show that domestic uptake of ice core publications by some Australian states demonstrated more ‘Active’ inclusions in policy to support an area of national interest: water security. The mixed methods piloted in this study can be used to assess scientific publications from national Antarctic programmes with more nuance, thereby offering an improved avenue for measuring research impact.

In recent decades, the extent of ice-free areas has been increasing in the South Shetland Islands (Maritime Antarctica). The coastal sector is one of the zones most significantly affected by glacial retreat, with newly exposed land surfaces undergoing a wide variety of post-glacial environmental processes. Coastal areas are characterized by both continental and marine ice dynamics, which in turn have major influences on the morphology and processes shaping coastal landforms. A detailed geomorphological analysis was carried out at Spanish Cove, south-west Livingston Island, which constitutes a boulder beach close to the Spanish Antarctic Station Juan Carlos I. This research provides a classification of the existing coastal landforms in this sector, as well as an analysis of the recent behaviour of the area using drone surveys, material size measurements obtained through semi-automatic techniques and hardness analysis using a durometer. This study represents one of the first attempts to classify the Antarctic coastal environment and offers a basis for understanding the potential evolution of such environments over the coming decades under global change and the rapid transformation of present-day glaciated landscapes.

The intensity and frequency of extreme weather events in rapidly changing environments continue to increase, driving unusual behaviours and posing significant threats to terrestrial ecosystems. In this study, we describe the co-occurrence of 1) Collembola swarming, 2) vegetation die-off and 3) extreme weather events, particularly heavy rainfall and high temperatures, over a 5 day period on sub-Antarctic Marion Island. Taxonomic and molecular evidence confirmed that the Collembola species displaying swarming behaviour was Ceratophysella denticulata, an invasive hypogastrurid. Our observations suggest that environmental stressors may have induced vegetation die-off, which, in turn, may have directly or indirectly driven Collembola aggregation. The association of these factors highlights the potential role of Collembola as bioindicators of soil ecosystem responses to climatic extremes, and that the recognition of these interactions can be critical in the prediction and management of ecological responses to changing environments.

The population status of Adélie penguins (Pygoscelis adeliae) on the Antarctic Peninsula highlights opportunities for the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) to address uncertainty more directly and effectively in its conservation efforts. The heightened uncertainty posed by climate change is testing CCAMLR’s commitment to balancing science and international cooperation in decision-making. Uncertainty underpins some of the justification to postpone reaching a consensus on the establishment of Marine Protected Areas, leaving Adélie penguins vulnerable to change. Two key opportunities to adapt current management approaches emerge: 1) reduce uncertainty by systematically identifying knowledge gaps within CCAMLR’s processes; and 2) integrate uncertainty more explicitly into decisions through a standardized approach to assessing and communicating it.

Concordia Station is a long-term lidar observatory in Antarctica. Its main purpose is to detect and classify polar stratospheric clouds (PSCs). In September 2023, water ice PSCs were observed for a period of 6 days. This has never occurred during the month of September in the 10 years of observations of PSCs at Concordia Station. In addition, the space-borne CALIOP (Cloud Aerosol Lidar with Orthogonal Polarization) lidar observed a rare occurrence of ice PSCs over Concordia Station during the first half of June. It is well known that the January 2022 eruption of the Hunga submarine volcano (20°32’S, 175°23’W) injected vast amounts of water vapour into the stratosphere. The Hunga hydration flooded southern high latitudes at the end of the 2022 austral winter, and the moist air was then entrained into the developing vortex in the austral autumn (April–May) of 2023. The increased water vapour from Hunga was reported to promote PSC formation by cooling the stratosphere and raising PSC formation temperatures. Here, we explore the impact of the Hunga eruption on the PSCs observed at Concordia Station.

Coastal erosion is a dynamic process driven by multiple environmental factors. In Antarctic regions, the interaction between wind, waves, sea ice, sediment transport and precipitation creates a complex setting for understanding shoreline change. This study focuses on Potter Cove, a small fjord in Maxwell Bay, south-west of King George Island (South Shetland Islands), where winter waves are investigated as a key erosive driver. Shoreline changes were assessed through satellite imagery, in situ beach profiling and sediment sampling. Additionally, a numerical wave modelling system was implemented to simulate wave dynamics within the cove. The results indicate a coastal retreat of up to 20 m along the southern shore of Potter Cove since 2020. Simulations for winter 2021 reveal two high-energy wave events with significant wave heights (Hs) of ~2 m, along with eight moderate events (Hs ≈ 1 m) occurring within the cove. The most energetic events (Hs = 2.11 m) originated offshore and entered directly through the cove’s mouth from the west-south-west. Conversely, moderate waves could be generated both internally and externally. Reduced sea-ice cover probably diminished the natural wave-buffering effect, enhancing the erosive impact of wave action on the coast. However, the absence of quantitative assessments of other relevant processes (e.g. permafrost thaw, glacial meltwater discharge, sea-level variability and sediment supply) limits our ability to gain a comprehensive understanding of the ongoing erosion. These findings highlight the role of wave dynamics in Antarctic coastal change and the need for integrated monitoring approaches.

The Fremouw Formation of the Central Transantarctic Mountains preserves the southernmost record of Early to Middle Triassic terrestrial ecosystems that developed in the aftermath of the end-Permian mass extinction. Although the well-studied vertebrate fossil assemblage in the lower member of the Fremouw Formation provides a detailed snapshot of subpolar ecosystems immediately following the end-Permian mass extinction, the nature of how long these earliest Triassic communities persisted at the southern extremes of Pangaea is virtually unknown. Importantly, the timing and extent of the major faunal turnover between the lower and upper members of the Fremouw Formation have been obscured by the paucity of fossil specimens historically recovered from the middle member. Here, we describe the first vertebrate assemblage from the middle member of the Fremouw Formation, including occurrences of procolophonids (including Procolophon trigoniceps) and archosauromorphs (including Prolacerta broomi), as well as infilled vertebrate burrow casts referrable to the ichnogenus Reniformichnus. We also summarize and expand on lithostratigraphic shifts between the lower, middle and upper members of the Fremouw Formation. Although the sample size of vertebrate body fossils is small compared to the lower and upper members of the Fremouw Formation, we discuss the evidence for a taphonomic shift between the lower and middle members of the Fremouw Formation that favours preservation of smaller-bodied taxa and individuals in the latter. Together, these preliminary data add crucial context to the persistence of subpolar vertebrate communities in the earliest Mesozoic.