A rock cairn, with two matchbooks buried beneath, was found on the summit of the highest hill on Thomas Island, Bunger Hills, East Antarctica. The matchbooks are most likely from United States World War II-era ration packs, which were distributed to various military and civilian expeditions from the mid-1940s into the 1950s. Bunger Hills was first visited by United States Navy ‘Operation Highjump’ in February 1947, when a seaplane most likely landed on a marine inlet, rather than a lake as reported previously. Thomas Island was first visited by United States Navy ‘Operation Windmill’ in January 1948, when a survey point was established, and it is probably this location that is marked by the rock cairn. The matchbooks were replaced beneath the cairn and the rocks replaced. Just over 76 years had elapsed between burial of the matchbooks, construction of the cairn and their rediscovery.

During a 2019 Chilean Antarctic Scientific Expedition (ECA 55) studying crustose coralline algae (CCA) diversity on the Antarctic Peninsula, bleaching of these algae was observed for the first time in this region. Here, we present initial findings on the physiological state of bleached and normally pigmented CCA (Clathromorphum sp.) assessed using chlorophyll-a fluorescence induction pulse amplitude modulation. The study site experienced high light exposure and salinity in the water column. Our analyses found that bleached CCA have relatively healthy photophysiology responses but lower photosynthetic efficiency, which could be associated with the low salinities recorded in the study area. However, seasonal monitoring and mesocosm experiments across the southern polar latitudes are urgently required to confirm this hypothesis.

Antarctica is populated by a diverse array of terrestrial fauna that have successfully adapted to its extreme environmental conditions. The origins and diversity of the taxa have been of continuous interest to ecologists since their discovery. Early theory considered contemporary populations as descendants of recent arrivals; however, mounting molecular evidence points to firmly established indigenous taxa far earlier than the Last Glacial Maximum, thus indicating more ancient origins. Here we present insights into Antarctica's terrestrial invertebrates by synthesizing available phylogeographic studies. Molecular dating supports ancient origins for most indigenous taxa, including Acari (up to 100 million years ago; Ma), Collembola (21–11 Ma), Nematoda (~30 Ma), Tardigrada (> 1 Ma) and Chironomidae (> 49 Ma), while Rotifera appear to be more recent colonizers (~130 Ka). Subsequent population bottlenecks and rapid speciation have occurred with limited gene transfer between Continental and Maritime Antarctica, while repeated wind- or water-borne dispersal and colonization of contiguous regions during interglacial periods shaped current distributions. Greater knowledge of Antarctica's fauna will focus conservation efforts to ensure their persistence.

Marambio (Seymour) Island is located in the James Ross Archipelago east of the Antarctic Peninsula. Although several research groups have carried out studies on the biodiversity on the island for decades, surveys of bryophytes have not been developed. That is why there are currently only six species of mosses recorded in the northern part of the island. During the 2021–2022 summer Antarctic field trip, 15 mosses species were surveyed in Marambio Island. Of the total number of collected species, nine are reported for the first time for Marambio Island. For the remaining four species, their distributions are now expanded to Marambio Island.

As a result of analysis of the ice cover, geological structure and tectonics of the underlying rocks in the Lake Vostok area of Antarctica, a layered sub-horizontal structure of the ice cover and a distribution of the parameters of the ice composition were established. The physical and mechanical properties of the underlying rocks were determined experimentally. Complex tectonics revealed an increase in geothermal flow in the Vostok Basin region, which plays a role in the evolution of the Earth's crust and in shaping the morphology of its physical properties. A three-dimensional geomechanical model of the unified system ‘glacier-Lake Vostok-bedrock ’ was constructed and investigated. Regularities in the changes to the stress-strain state were revealed. Zones of development of plastic deformation in the ice cover along the perimeter of Lake Vostok and their distribution over the lake were established, which were confirmed by results from field observations. Modelling of geomechanical processes shows that the change in the mechanical state of the Earth's crust, taking into account the creep deformation of the ice sheet, relates more to nonlinear dynamic systems, which are characterized by unstable changes and should be considered as fractal systems.

Continuous permafrost is present across the McMurdo Dry Valleys of southern Victoria Land, Antarctica. While summer active-layer thaw is common in the low-elevation portions of the Dry Valleys, active layers have not significantly thickened over time. However, in some locations, coastal Antarctic permafrost has begun to warm. Here, based on soil and meteorological measurements from 1993 to 2023, we show that wintertime soil temperatures have increased across multiple sites in the Dry Valleys, at rates exceeding the pace of summer soil warming. Linear warming trends over time are significant (P < 0.05) at six of seven soil monitoring sites. Winter warming is strongly correlated with increased numbers of down-valley wind events (Foehn/katabatics), but it may also be driven by increased incident longwave radiation at some stations (although winter longwave increase is not significant over time). While down-valley wind events increase winter warming, when down-valley wind events are excluded from the record, winter soil warming remains persistent and significant, suggesting that Antarctic soils are experiencing less cold winters over time in response to regional warming. Together, these observations suggest that some Antarctic permafrost may be approaching a transition to discontinuous permafrost in some regions as winter freezing intensity is reduced over time.