This study looks at the feasibility of using Ocean Acoustic Tomography for long-term monitoring of polynyas using both observations in Terra Nova Bay polynya (Ross Sea) and simulations with a range dependent, multi-layered adiabatic normal mode acoustic propagation model. The summer sound speed profile is characterized by surface values of around 1450 m s−1, a minimum of 1441 m s−1 around 50 m depth and a linear increase with a 0.016 s−1 slope. Thus, the sound propagation is apparently ducted in the near surface layer and is refracted upward below it. During winter, due to water cooling and mixing processes, the subsurface minimum disappears, the surface sound speed is about 1440 m s−1 and no near surface layer ducted propagation occurs. Because of the specificity of the Terra Nova Bay seasonal sound speed profile and to cope with both deep and shelf water applicability, the feasibility study of acoustic inversion was undertaken using normal mode Match Field Tomography instead of the more classical travel-time inversion. The results from simulations demonstrate that ocean acoustic tomography is able to reproduce quite well the vertical sound speed profile, in particular the temporal evolution of summer stratification and winter mixing processes, thus providing information on the upper layer, where direct measurements are not possible.

We report here the discovery of a boulder pavement cropping out at the base of the Hobbs Glacier Formation (Miocene), on the northern sector of Seymour Island (Isla Marambio), West Antarctica, along the contact with the underlying La Meseta Formation (Eocene). The feature described has many points in common with boulder pavements developed in tidal-marine environments. The clasts of the pavement are mostly boulders and bear up to three sets of glacial striae on their bevelled truncated surfaces, but are not elongate parallel to them or bullet shaped. No diamictite body was identified associated with the boulder pavement. These features differ from those of boulder pavements described from terrestrially glaciated Cenozoic deposits and may indicate a shallow glaciomarine environment for the late Cenozoic of Seymour Island.

Nowadays it is well accepted that background aerosols in the boundary layer over remote oceans are of marine origin and not aged continental. Particularly in the Atlantic sector of the Southern Ocean at least four main important regions exhibit significant ocean primary productivity. They are the Bellingshausen–Amundsen Sea, the Weddell Sea, the southern Argentinean shelf and the southern Chilean coast. In this work, we have combined ground-based continuous atmospheric sampling of aerosol number concentration (ANC), over-sea dimethyl sulphide (DMS) measurements, chlorophyll a (chl a) concentration provided by Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite images, in situ meteorological data and monthly regional NCEP-NCAR re-analysis wind fields in order to investigate the relative contribution of each of the above regions to the apportionment of the ANC at King George Island (KGI), South Shetland Islands. Our results suggest that, at least during the period from September 1998–December 1999, the southern Argentinean shelf acted as the main contributor to the ANC measured in KGI.

A unique homoxylous wood is described from the Albian Lewis Hill Member of the Whisky Bay Formation on James Ross Island as Mixoxylon australe Chernomorets & Sakala, gen. et sp. nov. This fossil taxon shows an unusual combination of features in having indistinct growth rings with a significantly wider earlywood zone than latewood zone, tracheids with scalariform to araucarian pitting, exclusively uniseriate rays with distinctly pitted both tangential and horizontal walls and araucarioid to podocarpoid cross-field pits. Its characteristics are intermediate between Phoroxylon Sze and Sahnioxylon Bose & Sah, so a new genus is proposed. Its systematic affinities are dubious, but it represents the southernmost evidence of the homoxylous Mesozoic wood with scalariform pitting described so far.

The Tristan klipfish, Bovichtus diacanthus, an endemic species at Tristan da Cunha Island was successfully aged using whole sagittal otoliths. The annulation pattern was clear, resulting in an alternating combination of opaque and translucent zones that form an annulus. Although sampling limitations did not allow direct validation of annual ring deposition, most otoliths showed a translucent edge, perhaps suggesting that the deposition of translucent zones is a synchronous process which takes place in winter coincident with the spawning season. The reliability of ageing methodology was supported by the good agreement between readings. The maximum age was estimated to be five years in females and four years in males. In order to increase the small number of direct readings, the length at age was back-calculated for each fish by fitting growth curves. The resulting growth of B.diacanthus was described by the von Bertalanffy growth model, as summarized by the following parameters: L∞ = 207.1 mm TL, k = 0.49 per year, and t0 = 0.04 years. The size at which 50% of the population spawns for the first time was c. 147 mm, corresponding to 2.5 years of age.

The Devonian, Pivot Coal Measures in southern Victoria Land are non-carbonaceous. The sequence contains bedding parallel, titaniferous ironstones up to 50 cm thick, but no coal or carbonaceous shale, the unit is consequently renamed Pivot Member of the Arena Sandstone. The more Fe-Ti oxide-rich (up to 40 modal %) beds appear black and coal-like with conchoidal fracture and closely spaced cleat-like fractures. The coal-like beds grade laterally and vertically into less altered sedimentary rocks in which fine bedding-parallel concentrations of Fe-Ti oxide pick-out parting surfaces on ripples and other sedimentary structures. Thin section petrography shows that the Fe-Ti oxide is replacive, and outcrop relationships show that the replacement was related to dolerite intrusion 200 million years after the sedimentary host was deposited. Replacement of muscovite, biotite and chlorite by Fe-Ti-oxide occurred at 179 ± 3 Ma, at pressures of 0.3–0.4 kbar and at temperatures as low as 380°C.

To study how teleosts have modified their immunoglobulin structures to adapt to the Antarctic environment, we investigated Trematomus bernacchii IgM at protein and gene levels. Serum IgM was purified, characterized and quantified. The nucleotide and deduced amino acid sequences of IgL and IgH were determined. Upon comparison with other teleosts, T. bernacchii IgH showed a higher hydrophilic character and the presence of two remarkable insertions, probably increasing the flexibility of the molecule. To investigate the amplitude of the antibody repertoire, a VH library was constructed. The analysis of rearranged VH/D/JH transcripts revealed a high occurrence of the RGYW motif and a clear bias in the usage of serine codons. Diversity generated by insertions/deletions occurred more often than in other species. VH sequences fell into only two gene families referred to as Trbe VH I and Trbe VH II. The deduced amino acid sequence of the membrane region was found to be the longest and an F/Y substitution was observed at a highly conserved position. Models of the transmembrane helices of T. bernacchii and other teleost Ig were constructed by molecular dynamics. Finally, the analysis of the antibody specificity revealed the presence of antibodies specific to the proteins of nematode parasites.

Whilst interest in the economic exploitation of the Southern Ocean resources dates back to the last part of the 18th century scientific research into elements of the marine ecosystem only began in the mid 19th century. As far as plankton and benthos are concerned the great exploratory voyages and expeditions laid a firm taxonomic foundation on which later work was built. The most outstanding expedition contribution was from the Discovery Investigations. Concern about uncontrolled exploitation stimulated the SCAR BIOMASS programme which in turn led to CCAMLR with its modelling programmes and top predator monitoring. Recent research on pack ice communities has been aided by dedicated ice-capable research vessels whilst unmanned photographic techniques as well as SCUBA diving and experimental research facilities in the Antarctic have encouraged major research on benthos. International collaboration, interdisciplinary research and good ideas suggest Antarctic marine biology has a bright future.

The shallow benthos along the western Antarctic Peninsula supports brown macroalgal forests with dense amphipod assemblages, commonly including Gondogeneia antarctica (Amsler et al. 2014). Gondogeneia antarctica and most other amphipods are chemically deterred from consuming the macroalgae (Amsler et al. 2014). They primarily consume diatoms, other microalgae, filamentous macroalgae and a few undefended macroalgal species, including Palmaria decipiens (Aumack et al. 2017). Although unpalatable when alive, G. antarctica and other amphipods will consume the chemically defended brown algae Himantothallus grandifolius and Desmarestia anceps within a few weeks of death (Amsler et al. 2014).

The diet of post-breeding Antarctic shags Phalacrocorax bransfieldensis was investigated at four colonies at the Danco Coast, Antarctic Peninsula, by the analysis of 399 pellets (regurgitated casts) collected during February and March 1998 and 2000. Overall, demersal-benthic fish were the most frequent and important prey at all the colonies sampled, followed by octopods and gastropods. Amongst the fish, Notothenia coriiceps and Gobionotothen gibberifrons were the main prey in all of the sampling sites in both seasons. The composition of the diet of post-breeding shags differed from that observed in the previous breeding season. Post-breeders preyed on the same fish species consumed by breeders, although in different proportions and on larger specimens. The information provided here differs from that reported for post-breeding individuals belonging to other shag species and also for post-breeding Antarctic shags. Our results, as well as the differences with previous studies, are discussed in relation to differences in prey availability among localities and to the use of alternative foraging grounds at the end of the breeding period.

This study describes SNOW-WEB, a distributed system of atmospheric sensors, which is cost-effective and can be efficiently deployed in Antarctica. The system supports traditional atmospheric sensors and has built-in redundancy as many units can be deployed in a relatively small area for a similar cost to one conventional weather station. Furthermore, each unit is equipped with wireless mesh-networking capabilities and so is able to share information with those units in its direct vicinity. This allows for the ferrying of collected information to a manned observation station and hence the ability to monitor data in real-time. GPS hardware installed on each unit also allows for high-resolution glacier or ice shelf tracking. As a testing study, eighteen such weather stations were deployed in the vicinity of Scott Base, Ross Island, Antarctica over the 2011/12 summer season. This paper reports on the successful development and deployment of the system, results from the testing period and challenges encountered during the experiment. Collected data is validated against automatic weather stations already operating in the region and an intercomparison is performed between SNOW-WEB data and forecast output from the Antarctic Mesoscale Prediction System. A high degree of agreement is found between data sources. We conclude that SNOW-WEB data is suitable for use in studies of mesoscale meteorology.

Deciphering the sub-ice geology in the Wilkes Subglacial Basin region is important for understanding solid earth-ice sheet evolution and for assessing geological ties between East Antarctica and formerly contiguous Australia. We analyse marine sediment samples derived from drill site U1359 of Integrated Oceanic Drilling Program Expedition 318. Our study reports for the first time that the inland sediment source area comprises a complex mafic igneous terrain and a metamorphosed Precambrian subglacial basement. Pyroxene geochemical analyses confirm the presence of tholeiitic to calc-alkaline basalts. The high-grade part of the subglacial terrain contains upper amphibolite to granulite facies rocks that are comparable to Archaean to Palaeoproterozoic rocks exposed in the Terre Adélie Craton and the formerly adjacent Gawler Craton in Australia. Chemical Th-U-total Pb isochron method (CHIME) ages extracted from a subhedral monazite grain associated with the low-grade biotite-muscovite schist rock fragment provide a unimodal age of 799 ± 13 Ma. Rare occurrences of 800 Ma age in the Terre Adélie Craton and/or George V Coast provide evidence for the presence of at least one late Neoproterozoic magmato-metamorphic event in the interior of Wilkes Land. The affinity of the unexposed geological domains of Wilkes Land, East Antarctica, with their Australian counterparts is discussed in the context of the Rodinia supercontinent.

More than 60 years since it entered into force in 1961, the Antarctic Treaty is experiencing significant challenges. These challenges also affect its associated instruments known as the Antarctic Treaty System (ATS). These are mostly external dynamics that are increasingly challenging the ATS from outside of the Antarctic region. They encompass a spectrum of issues relating to global legal regimes and to what extent they are applicable in the Antarctic context. Climate change appears to be the most significant of these challenges, as the tangible planetary impacts of global warming and the perception of its urgency and seriousness by states have prompted additional challenges to the ATS. The physical changes that continue to be scientifically unveiled in the Antarctic are manifesting severe impacts on a planetary scale, and this fact has underscored the need for broader and more rapid international engagement within the Antarctic governance discourse. Nevertheless, the existing decision-making mechanisms compounded by the adversarial atmosphere within the ATS due to external factors have become challenges of themselves. Such challenges call for the re-contemplation and reassessment of the legal regime of the Antarctic in general, and the ATS in particular, to find ways forward for an otherwise historically effective international legal system. This paper utilizes both scientific and legal lenses to underscore the urgent need to achieve better communication between the ATS generally, the Antarctic Treaty Consultative Meetings specifically and the UN Framework Convention on Climate Change and Intergovernmental Panel on Climate Change regimes and to overcome the multiple barriers that stand in the way of achieving that objective.

We present the first quantitative attempt at reconciling the source and emplacement of granite erratics in Beacon Valley. The erratics are enigmatic because granite does not crop out in the valley and its nearest subaerial exposure is at least 10 km downstream to the east of the valley. Detailed mapping of the valley shows three types of granite erratics, which are not present in equal amounts and do not show spatial patterns. Pb isotopic and elemental compositions of the erratics eliminate the Metschel Tillite as a source and indicate they derive from the Dry Valley plutons. Our limited study tentatively ties the erratics to suites of plutons, but it does not allow a direct tie of the erratics to specific plutons because of i) the geochemical variability of the plutons and ii) the limited number of erratics that were analysed. Published data suggest the erratics provide evidence of wet-based glaciation, which covered the Dry Valleys and much of Antarctica during the mid-Miocene. Our paper also explains the problems associated with the emplacement of these erratics and the age of the massive ice in Beacon Valley.

Pelagic seabirds often nest on islands that are far from productive foraging areas. The Procellariiformes (petrels, shearwaters and albatrosses) are among the longest-ranging seabirds; they have several adaptations that permit them to efficiently utilize distant foraging areas and fast for long periods during incubation (Phillips & Hamer 1999). Giant petrels (Macronectes spp.) are large surface-nesting procellariiforms. They feed both by direct predation and by scavenging carrion, and they are the largest avian predator-scavengers in the Southern Ocean. Among procellariiform seabirds, one partner forages while their mate remains on the nest to incubate their single egg (Warham 1990). Northern giant petrels (Macronectes halli) have incubation shifts lasting up to 17 days (Cooper et al. 2001). In general, incubating procellariiform seabirds do not feed during their shift (Warham 1990). We report the first case to our knowledge of a procellariiform seabird, a northern giant petrel, actively feeding at its nest whilst incubating.

Scullin and Murray monoliths are thought to hold the largest concentration of breeding seabirds in East Antarctica. The monoliths were designated as an Antarctic Specially Protected Area (ASPA No. 164) in 2005 in recognition of the global importance of the seabird assemblages and to protect their outstanding ecological and scientific values. The management plan for the Scullin and Murray Monoliths ASPA encourages regular seabird population monitoring using methods such as aerial photography, but the complex logistics of accessing this remote site has until now limited quantitative assessment of the seabird populations to a single survey in 1986/87. In December 2010 we photographed the Adélie penguin population to provide the population counts presented here. We discuss the potential biases and uncertainties in estimating the breeding population from both the recent and 1980s population count data.