The distribution of annual mean biomass of mesozooplankton (animals in the size range 0.2–20 mm) in the upper layer (0–100 m) of the Atlantic sector of the Southern Ocean was mapped. The map was constructed from 4216 measurements at 2184 oceanographic stations, from the Russian and Brazilian archive records, from published sources, and from the British Oceanographic Data Centre. The annual mean mesozooplankton biomass value for the South Atlantic is estimated in this study to be 93 mg m−3 wet weight.

Details are presented of seismic velocities at a site near Rothera Point, Adelaide Island, Antarctic Peninsula. The snow/firn velocity structure was obtained using a 24-channel Bison 9000 seismograph, recording the outputs of geophones of 40 Hz natural frequency attached to 150 mm snow spikes. The refraction velocity of the underlying bedrock was measured using a 48-channel DFS V recorder and 10 Hz geophones. The records were obtained during trials of equipment and techniques which took place in the 1988–89 and 1990–91 seasons. The data will be of interest to other investigators studying firn structure around Antarctica or considering crustal seismology in the Antarctic Peninsula region.

The changes implemented in 2005 in the development strategies of Antarctic science carried out by Chile have had a positive impact on the scientific productivity of the Chilean Antarctic Science Program (PROCIEN). We analysed scientometric indicators from between 2009 and 2019. The bibliographic data were extracted from the Web of Science database using search query keywords. We used multiple correspondence analysis to identify specific trends and also network analyses of international collaboration in VOSviewer. The number of Antarctic science publications in Chile has gradually increased from 21 in 2009 to 95 in 2019. The rise in the number of articles was higher in journals for the first impact factor quartile. Research lines showing increased first-quartile impact factor papers corresponded to Antarctic ecosystems, biotechnology and geosciences. The main geographical domains in which such research activities have been carried out corresponded to in the South Shetland Islands and the Antarctic Peninsula. Fieldwork data are the main sources for the production of scientific articles, and there are three science platforms within which most of these papers concentrate. The diversification of funding sources, the implementation of improvements in the selection process and Chile's alignment with Scientific Committee on Antarctic Research programmes have contributed to improving the science that Chile has developed in Antarctica.

At former Antarctic research stations, legacy waste often remains in situ and concealed by ice. Consequently, the location, characteristics and potential environmental impact associated with legacy waste remains poorly documented. This study applies ground magnetometry to map the spatial extent of the landfill at the abandoned Wilkes Station. Magnetic anomalies indicate that the landfill extends north-west to south-east and is close to, and perhaps prograding into, the ocean. The landfill is characterized by large magnetic variations of > 1500 nT with asymmetrical magnetic anomalies which suggest variable orientations of material and random dumping. Magnetic susceptibilities > 0.02SI units beyond the landfill area reveal elevated magnetic properties of the basement geology. However, a contrast in anomaly shape reliably distinguishes large anomalies generated by landfill material. Surface and subsurface melt streams (observed at the shoreline) flowing from the survey area suggest elevated potential for metal contamination of the nearshore and marine environment. The survey demonstrates a cost-effective and non-invasive method for gathering information to guide the clean up of landfills beneath ice.

Unmanned magnetometer stations (UMS) have been developed and were installed at remote location near Syowa station, Antarctica (69°S, 40°E) to perform field tests in the harsh Antarctic environment. The UMS was powered by a thermo-electric generator fuelled by kerosene (LTEG) which supplies 87 Watts continuously to the load. The LTEG and instrumentation (flux gate magnetometer, data logger, chronometer) were installed in a thermally insulated shelter (0.9 m by 1.8 m by 1.9 m). The shelter and an 800 l fuel tank were mounted on a sled, and were towed by snow tractor. The UMS were installed at Kizahasi beach, Skarvsnes (50 km south-west of Syowa) and at H-100 of the Mizuho route (100 km south of Syowa) in the early spring of 1988 and operated until the end of the year. The data obtained will be used for a study of the spatial phase and amplitude structure of the ionospheric current systems and a response of the local induction currents to them.

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.

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.

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.

The structural basement of Alexander Island consists of a wide belt of accretionary complex rocks, the LeMay Group (Bum 1984). This is overlain by ?Cretaceous-Tertiary calcalkalinevolcanic rocks (Bum 1981), and intruded by several slightly younger, but related, plutons (Care 1983). The Rouen Mountains batholith is a large group of these plutons which occurs in the northern part of the island.

There is a potential threat to marine mammals from acoustic signals emitted by hydroacoustic devices. The impact on the hearing of marine mammals depends on the technical parameters of the instruments and on the exposure of the animal to noise pulses, as well as on the properties of the biological system, that is to say, on the anatomy and the audiogram of the animal. Here, the blue whale, the sperm whale and the beaked whale are taken as examples in an investigation of the potential exposure to noise pulses from the hydroacoustic instruments Hydrosweep and Parasound. Diving depths of the whales and relative speeds of the animals with respect to the survey vessels are taken into account, as well as the area impacted by the equipment, in estimating the level of sound needed to produce “temporary threshold shift” in an animal. The results suggest that auditory damage is only likely if animals pass the transducer at close range and that the impact on marine mammals can be mitigated by implementing prior detection and shut down procedures.

Nuculid bivalves of the Cape Melville Formation (Early Miocene, King George Island) are reviewed. Ten bivalve taxa are listed from the formation in the families Nuculidae (two species), Sareptidae, Malletiidae, Limopsidae (two species), Limidae, Pectinidae, Hiatellidae, and Periplomatidae. The Nuculidae consist of two species of Leionucula Quenstedt, 1930. One of these, L. melvilleana n. sp., is described and the other consists of the two species named previously by Anelli et al. (2006), which are demonstrated to be synonymous and are assigned to the species Leionucula frigida (Anelli, Rocha-Campos, Santos, Perinotto & Quaglio 2006). This assemblage, dominated by protobranchs (89% of specimens), is a typical fauna of offshore soft substrates, with a few specimens transported from hard substrates nearby. The diversity of Nuculidae has decreased in the Antarctic region through the Cenozoic.

An interception trap to collect airborne arthropods under extreme weather conditions is described. The trap, constructed from durable materials, is operated by wind pressure. It consists of a funnel of fine brass gauze mounted inside a cylinder of stainless steel that rotates into the wind on a mast at 1.5 m from the ground. The gauze funnel terminates in a removable, propanol-filled, collecting bottle into which airborne material accumulates. The counterbalanced cylinder rotates around a central shaft on roller bearings and faces into the wind. Two traps were successfully operated continuously for four and five years, respectively, on sub-Antarctic Macquarie Island and have collected large numbers of airborne arthropods and other biological material over this period.