Found 14053 items
1 January, 2012 by Michael Meredith
The supply of nutrients to the low-latitude thermocline is largely controlled by intermediate- depth waters formed at the surface in the high southern latitudes. Silicic acid is an essential macronutrient…1 January, 2012 by Eugene Murphy, Simeon Hill
Foodweb models provide a useful framework for compiling data on biomass, production, consumption and feeding relationships. They are particularly useful for identifying gaps and inconsistencies in the data, and for…Read more on A foodweb model to explore uncertainties in the South Georgia shelf pelagic ecosystem
1 January, 2012 by Guy Hillyard, Melody Clark
Fifteen species of marine invertebrate commonly occurring in the near-shore environment of Rothera base, Antarctica, were used to test tissue sample storage protocols with regard to preservation of RNA integrity.…Read more on RNA preservation of Antarctic marine invertebrates
1 January, 2012 by Richard Hindmarsh, Richard Hindmarsh
An analytical theory is developed for ice flow velocity in a boundary layer couplet at the calving front. The theory has simple quantitative characteristics that relate ice front velocity to…1 January, 2012
The Southern Ocean is largely a High Nutrient Low Chlorophyll (HNLC) region where macronutrient concentrations are high and phytoplankton productivity is low. However, there are productive ‘hot spots’ that sustain…Read more on Responses of microplankton community structure to iron addition in the Scotia Sea
1 January, 2012
The Southern Ocean is an important biogeochemical region on a global scale, in which mineralising phytoplankton play a role in cycling energy, carbon and nutrients. Mineralising phytoplankton with cells 2–20…1 January, 2012 by Andreas Cziferszky, Dominic Hodgson, Peter Convey, Peter Fretwell
We studied the glacial geomorphology and geochronology of two ice-free valleys in the Dufek Massif (Antarctic Specially Protected Area 119) providing new constraints on past ice sheet thickness in the…1 January, 2012 by Lloyd Peck, Melody Clark
Although recent years have witnessed a rapid growth in the number of genetic studies of Antarctic organisms, relatively few studies have so far used nuclear markers, possibly due to the…1 January, 2012 by Andrew Clarke, Lloyd Peck, Melody Clark, Peter Fretwell
Several recent empirical studies have challenged the prevailing dogma that broadcast-spawning species exhibit little or no population genetic structure by documenting genetic discontinuities associated with large-scale oceanographic features. However, relatively…1 January, 2012 by Jaume Forcada
Natal philopatry is an important component of mammalian behaviour but is difficult to study in natural vertebrate populations due to the requirement for long-term individual-based spatial observations. Consequently, we quantified…Read more on Extreme natal philopatry in female Antarctic fur seals (Arctocephalus gazella)
1 January, 2012 by Paul Holland
The sea-ice cover around Antarctica has experienced a slight expansion in area over the past decades1, 2. This small overall increase is the sum of much larger opposing trends in…1 January, 2012 by Richard Horne
Weather forecasting has expanded to space weather. As of 1 March 2012, satellite operators and the general public will be able to obtain forecasts of the Earth’s radiation belts, thanks…1 January, 2012 by Scott Hosking
We introduce a methodology to visualise rapid vertical and zonal tropical transport pathways. Using prescribed sea-surface temperatures in four monthly model integrations for 2005, we characterise preferred transport routes from…Read more on Tropical convective transport and the Walker circulation
1 January, 2012 by Kevin Hughes, Peter Convey
Continental Antarctic terrestrial and freshwater environments currently have few established non-native species compared to the sub-Antarctic islands and other terrestrial ecosystems on Earth. This is due to a unique combination…1 January, 2012 by Jennifer Jackson
Humpbacks breeding in East Australia (E1) and Oceania (New Caledonia E2, Tonga E3 and French Polynesia F) in the South Pacific are thought to be demographically independent, due to significant…1 January, 2012 by Jennifer Jackson
Rapid advances in molecular genetic techniques and the statistical analysis of genetic data have revolutionized the way that populations of animals, plants and microorganisms can be monitored. Genetic monitoring is…Read more on Guidelines for collecting and maintaining archives for genetic monitoring
1 January, 2012 by Adrian Jenkins
A few decades ago, Antarctic ice sheets were expected to grow as the atmosphere warmed and increasing poleward moisture transport added snowfall to regions that would remain below freezing year-round.…1 January, 2012 by Adrian Fox
Changes in the volume and extent of land ice of the Svalbard archipelago have been the subject of considerable research since their sensitivity to changes in climate was first noted.…Read more on Observations of enhanced thinning in the upper reaches of Svalbard glaciers
1 January, 2012 by David Pearce
Spatial patchiness in marine surface bacterioplankton populations was investigated in the Southern Ocean, where the Antarctic Circumpolar Current meets the islands of the Scotia Arc and is subjected to terrestrial…1 January, 2012 by Adrian Jenkins, Pierre Dutrieux
In recent years, mass loss from the Antarctic Ice Sheet has contributed nearly 0.5 mm yr–1 to global mean sea level rise, about one-sixth of the current rate (Church et…1 January, 2012
We placed light-level geolocators on 17 Rusty Blackbirds (Euphagus carolinus) in 2009 to track their migrations from nest sites near Anchorage, Alaska to wintering areas and back. We recaptured three…Read more on Identifying migratory pathways used by Rusty Blackbirds breeding in Southcentral Alaska
1 January, 2012 by Joanne Johnson, Philip Leat
Recent changes along the margins of the Antarctic Peninsula, such as the collapse of the Wilkins Ice Shelf, have highlighted the effects of climatic warming on the Antarctic Peninsula Ice…Read more on The deglacial history of NW Alexander Island, Antarctica, from surface exposure dating
1 January, 2012 by Hugh Venables
The influence of the island mass effect of South Georgia on the seasonal marine carbon cycle was investigated during austral summer (January–February) 2008. South Georgia (54–55°S 36–38°W) lies on the…1 January, 2012
Understanding the variability and coherence of surface ocean pCO2 on a global scale can provide insights into its physical and biogeochemical drivers and inform future samplings strategies and data assimilation…Read more on Autocorrelation characteristics of the surface ocean pCO2 and air-sea CO2 fluxes
1 January, 2012 by Peter Convey
It is not clear for how long Antarctic soil nematodes might tolerate freezing. Samples of the Antarctic moss, Bryum argenteum, were collected on 1 October 1983 at Langhovde, Soya coast,…1 January, 2012 by David Vaughan
Radio-echo sounding (RES) of polar ice sheets reveals extensive internal layering. The degree of continuity of internal layering holds critical information about the ice-flow field, but previous analyses of this…1 January, 2012 by Victoria Peck
Environmental changes associated with the Paleocene–Eocene thermal maximum (PETM, ∼56 Ma) have not yet been documented in detail from the North Sea Basin. Located within proximity to the North Atlantic…1 January, 2012 by Mark Belchier
Krill forms an important part of the diet of many Antarctic fish species. An understanding of the role of fish as krill predators in the Southern Ocean is critical to…1 January, 2012 by Claus-Dieter Hillenbrand
The goal of this study is to assess the changes that have occurred during the Mid-Pleistocene Transition, an important transitional period in cryosphere evolution, by examining the siliceous microfossil record…1 January, 2012 by Hugh Venables, Peter Ward
Surveys of the microplankton communities of the Scotia Sea, Southern Ocean, were carried out during three separate seasons of interest, spring, summer, and autumn of consecutive years. The surveys were…1 January, 2012 by Zhaomin Wang
The transport of the AntarcticCircumpolarCurrent (ACC) varies strongly across the coupled GCMs (general circulation models) used for the IPCC AR4. This note shows that a large fraction of this across-model…1 January, 2012 by Adrian Fox, David Vaughan
From approximately 400 glaciers of the western Antarctic Peninsula, no in situ records of mass balance exist and their recent contribution to sea level is consequently poorly constrained. We seek…Read more on Multi-decadal glacier surface lowering in the Antarctic Peninsula
1 January, 2012
Ice core data from Antarctica provide detailed insights into the characteristics of past climate, atmospheric circulation, as well as changes in the aerosol load of the atmosphere. We present high-resolution…1 January, 2012 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
The Last Glacial Maximum (LGM; ca 23–19 ka BP) extent of grounded ice in the Filchner Trough, a major cross shelf trough extending seaward from the Filchner Ice Shelf in…1 January, 2012 by Adrian Fox, Philip Leat
1 January, 2012 by Chester Sands, Jennifer Jackson, Katrin Linse, Will Goodall-Copestake
High throughput sequencing technologies are revolutionizing genetic research. With this ‘‘rise of the machines’’, genomic sequences can be obtained even for unknown genomes within a short time and for reasonable…1 January, 2012
Trophic relationships and vertical distribution patterns of dominant mesozooplankton (2–20 mm) and macrozooplankton (>20 mm) invertebrates (Euphausiacea, Copepoda, Decapoda, Amphipoda, Thecosomata and Lophogastrida) were investigated within the epi- and meso-pelagic…1 January, 2012 by Andrew Wood, Richard Phillips
Numerous studies of wild animal species have documented that population level responses to environmental change are underpinned by individual level phenotypic plasticity. However, where the relationship between an individual trait…1 January, 2012 by Claus-Dieter Hillenbrand
We review the geomorphological, sedimentological and chronological evidence for palaeo-icestreams on the continental shelf of Antarctica and use this information to investigate basal conditions and processes, and to identify factors…1 January, 2012 by Philip Trathan
As important marine mesopredators and sensitive indicators of Antarctic ecosystem change, penguins have been a major focus of long-term biological research in the Antarctic. However, the vast majority of such…1 January, 2012 by Katrin Linse
The crustacean genus Rhachotropis has a worldwide distribution and amongst the largest bathymetric range known from any amphipod genus. DNA barcoding of new material from around New Zealand and the…1 January, 2012 by Katrin Linse
DNA barcoding revealed four well-supported clades among amphipod specimens that keyed out to Epimeria georgiana Schellenberg, 1931, three clades with specimens from the southern Scotia Arc and one clade with…1 January, 2012 by Eugene Murphy, Nadine Johnston, Peter Ward, Simeon Hill
Since the Discovery Investigations of the 1920s and 1930s, seawater temperatures have increased in the Atlantic sector by ∼1 °C; greater than the global mean rise. The aims of this…1 January, 2012 by Richard Phillips
Capsule Great Skuas Stercorarius skua breeding in Scotland, Iceland, and Norway, winter in different areas. Aims To assess the winter distribution of adult Great Skuas breeding in different countries. Methods…1 January, 2012 by Hilmar Gudmundsson, Keith Makinson, Keith Nicholls
Recent GPS observations from a spatially extensive network across Ronne Ice Shelf show significant daily ice flow variations. At all sites, the almost-synchronous horizontal displacements occur at diurnal and semidiurnal…Read more on Diurnal and semidiurnal tide-induced lateral movement of Ronne Ice Shelf, Antarctica
1 January, 2012 by Katrin Linse
Chemosynthetic primary production by microbes supports abundant faunal assemblages at deep-sea hydrothermal vents, with zonation of invertebrate species typically occurring along physico-chemical gradients. Recently discovered vent fields on the East…1 January, 2012 by Carlos Martin Garcia, Hilmar Gudmundsson
Ice flow in divide areas is strongly anisotropic. The evolution of ice fabric, from the onset of divide flow towards steady state with a fully developed fabric, has been shown…1 January, 2012 by Pierre Mathiot
Short-term and decadal sea-ice prediction systems need a realistic initial state, generally obtained using ice–ocean model simulations with data assimilation. However, only sea-ice concentration and velocity data are currently assimilated.…Read more on Better constraints on the sea-ice state using global sea-ice data assimilation
1 January, 2012 by Jaume Forcada
The coastal spotted dolphin (Stenella attenuata graffmani) is one of the most common species of dolphin in inshore Pacific waters of Costa Rica. We conducted surveys in protected waters of…1 January, 2012 by Michael Meredith
The sensitivity of the overturning circulation in the Southern Ocean to the recent decadal strengthening of the overlying winds is being discussed intensely, with some works attributing an inferred saturation…1 January, 2012 by Anje-Margriet Neutel
It has been shown that in real food webs, the strongest omnivorous feedback, a three-link positive feedback, is a good indicator of system stability, suggesting that the strongest positive feedback…1 January, 2012 by Peter Convey
Few non-native species have colonized Antarctica, although increased human activity and accelerated climate change may increase their number, distributional range, and effects on native species on the continent. We searched…1 January, 2012 by Richard Phillips
Protection of the marine environment lags far behind that of terrestrial domains. To help ameliorate this circumstance, top predators are being tracked to identify important ocean habitats, biodiversity hotspots and…1 January, 2012 by Lloyd Peck, Michael Thorne, Simon Morley
To further investigate the previously reported limited acclimation capacities of Antarctic marine stenotherms, the Antarctic mud clam, Laternula elliptica (King and Broderip, 1830–1831), was incubated at 3.0 °C for 89…1 January, 2012 by Lloyd Peck, Melody Clark, Simon Morley
While, in lower latitudes, population-level differences in heat tolerance are linked to temperature variability, in the Southern Ocean remarkably stable year-round temperatures prevail. Temporal variation in the physiology of Antarctic…1 January, 2012 by Michael Thorne, Simon Morley
The thermal reaction norms of 4 closely related intertidal Nacellid limpets, Antarctic (Nacella concinna), New Zealand (Cellana ornata), Australia (C. tramoserica) and Singapore (C. radiata), were compared across environments with…1 January, 2012 by Richard Phillips
Seabirds are important components in marine ecosystems. However, knowledge of their ecology and spatial distribution during the non-breeding season is poor. More investigations during this critical period are required urgently,…1 January, 2012 by Howard Roscoe
We present surface layer measurements made over Hudson Bay seaice during February/March 2008 from the COBRA (Impact of combined iodine and bromine release on the Arctic atmosphere) experiment which formed…1 January, 2012 by Louise Sime, Richard Hindmarsh, Robert Mulvaney, Richard Hindmarsh
Rapid warming over the past 50 years on the Antarctic Peninsula is associated with the collapse of a number of ice shelves and accelerating glacier mass loss1, 2, 3, 4, 5,…Read more on Recent Antarctic Peninsula warming relative to Holocene climate and ice shelf history
1 January, 2012 by Andrew Clarke, Andrew Fleming, Eugene Murphy, Geraint Tarling, Iain Staniland, Jaume Forcada, Jonathan Watkins, Martin Collins, Michael Meredith, Nadine Johnston, Peter Enderlein, Paul Rodhouse, Philip Trathan, Peter Ward, Rachel Cavanagh, Sally Thorpe, Simeon Hill
Analysis of the operation of ocean ecosystems requires an understanding of how the structure of the ecosystem is determined by interactions between physical, chemical and biological processes. Such analysis needs…Read more on Spatial and Temporal Operation of the Scotia Sea Ecosystem
1 January, 2012 by Eugene Murphy, Nadine Johnston, Philip Trathan, Rachel Cavanagh, Simeon Hill
The Southern Ocean supports diverse and unique ecosystems that have been impacted by more than two centuries of exploitation and are now experiencing rapid changes in ocean temperature and seasonal…1 January, 2012 by Eugene Murphy
Southern Ocean ecosystems matter for us all because they are important in Earth System processes and contribute to food security; they are also undergoing some of the most rapid changes…1 January, 2012 by Michael Meredith
Due to its position as the principal connector of the major ocean basins, the Southern Ocean strongly impacts climate, sea level, biogeochemical cycles and biological productivity on a global scale.…1 January, 2012 by Richard Horne
This paper is a companion to a paper by Liang et al. (2011) which reports a causal connection between the intensification of electrostatic ECH waves and the postmidnight diffuse auroral…1 January, 2012 by Hugh Corr, Keith Makinson, Keith Nicholls
We have discovered a band of stones and coarse sand in the Ronne Ice Shelf, Antarctica, some 60m above the ice shelf’s base, 40km from its seaward edge and 420km…1 January, 2012 by Will Goodall-Copestake
Mating between relatives often results in negative fitness consequences or inbreeding depression. However, the expression of inbreeding in populations of wild cooperative mammals and the effects of environmental, maternal and…Read more on Inbreeding and inbreeding depression of early life traits in a cooperative mammal
1 January, 2012 by Claus-Dieter Hillenbrand
Reconstructing past detrital flux and provenance in the SouthernOcean provides information about changes in source regions associated with climate variations and transport pathways. We present a LastGlacial Maximum (LGM) to…1 January, 2012 by Peter Convey
During the last 50 years, the western coast of the Antarctic Peninsula and adjacent archipelagos, also known as the maritime Antarctic, has experienced notable climate warming. As a result, expansion…1 January, 2012 by Andrew Clarke, David Pearce, Eugene Murphy, Nadine Johnston
The Antarctic continent is almost entirely covered by a vast icecap that reaches 4 km in thickness. Despite this, the continent possesses a remarkable array of lake ecosystems, many of…1 January, 2012 by David Pearce, Kevin Newsham, Michael Thorne
Our current understanding of Antarctic soils is derived from direct culture on selective media, biodiversity studies based on clone library construction and analysis, quantitative PCR amplification of specific gene sequences…Read more on Metagenomic analysis of a a southern maritime Antarctic soil
1 January, 2012 by Dominic Hodgson, Peter Convey
Heterotrophic bacteria isolated from five aquatic microbial mat samples from different locations in continental Antarctica and the Antarctic Peninsula were compared to assess their biodiversity. A total of 2,225 isolates…Read more on Heterotrophic bacterial diversity in aquatic microbial mat communities from Antarctica
1 January, 2012 by Sandra McInnes, Sandra McInnes
A new species of eutardigrade, Hebesuncus mollispinus, sp.nov. is described from Charcot Island, maritime Antarctica. The three knowm species of Hebesuncus are either widespread with questionable reports from the Antarctic…1 January, 2012 by Richard Phillips
Two hypotheses have been proposed to explain sex-related differences in foraging in sexually monomorphic seabirds. The ‘intersexual competition’ hypothesis suggests that parents are in competition and that the dominated sex…1 January, 2012 by Geraint Tarling, Peter Ward
Many calanoid copepods inhabiting high latitude environments overwinter at depth in the water column in a state of diapause and the large wax ester reserves that they contain are central…Read more on Wax ester composition influences the diapause patterns in the copepod Calanoides acutus
1 January, 2012
A new perspective on the role of lipids in zooplankton is proposed, with solid–liquid phase transitions of lipids being a factor regulating their buoyancy. These phase transitions are controlled by…1 January, 2012 by Geraint Tarling
Fatty acid biomarkers analysis was performed on juvenile and adult northern krill (Meganyctiphanes norvegica) to determine variability in diet between individuals and the consequences for their growth rates. Animals were…Read more on Diet and growth rates of Meganyctiphanes norvegica in autumn
1 January, 2012 by David Vaughan, Hamish Pritchard
Accurate prediction of global sea-level rise requires that we understand the cause of recent, widespread and intensifying1, 2 glacier acceleration along Antarctic ice-sheet coastal margins3. Atmospheric and oceanic forcing have…Read more on Antarctic ice-sheet loss driven by basal melting of ice shelves
1 January, 2012
The dataset Future Flows Climate was developed as part of the project ''Future Flows and Groundwater Levels'' to provide a consistent set of climate change projections for the whole of…1 January, 2012 by Andrew Clarke, Eugene Murphy, Lloyd Peck, Nadine Johnston
It is widely accepted that marine biogeography is largely shaped by direct effects of temperature (Angel, 1991; Murawski, 1993). Temperature also influences biodiversity patterns at various latitudes (e.g.,Royet al.,1998; Astorga…1 January, 2012
In recent years, phytoplankton phenology has been proposed as an indicator to monitor systematically the state of the pelagic ecosystem and to detect changes triggered by perturbation of the environmental…1 January, 2012 by Norman Ratcliffe, Philip Trathan
Managing fisheries in an ecologically sensitive manner demands that catches do not depress stocks within the foraging areas used by predators to levels that reduce their reproductive success or survival.…1 January, 2012 by Richard Phillips
Petrels are highly mobile seabirds that face many threats and whose conservation is frequently hampered by a lack of understanding of their biology at sea. We used a combination of…1 January, 2012 by Katrin Linse
The Antarctic Peninsula has experienced a rapid increase in atmospheric temperature over the last 50 years. Whether or not marine organisms thriving in this cold stenothermal environment are able to…1 January, 2012 by Angelika Renner, Eugene Murphy, Jonathan Watkins, Michael Meredith, Sally Thorpe
Pathways and rates of ocean flow near the Antarctic Peninsula are strongly affected by frontal features, forcings from the atmosphere and the cryosphere. In the surface mixed layer, the currents…1 January, 2012 by Lloyd Peck, Simon Morley
There are areas on Earth where it is pressing that we obtain an understanding of the thermal limits and acclimationcapacities of the species living there. These are the zones where…Read more on Thermal acclimation capacity for four Arctic marine benthic species
1 January, 2012 by Teal Riley
New geological mapping combined with U–Pb ion microprobe zircon geochronology on the isolated but locally extensive exposures of crystalline basement inliers of eastern Graham Land has greatly improved our understanding…1 January, 2012 by Teal Riley
The Mesozoic fore-arc of the Antarctic Peninsula is exposed along its west coast. On Adelaide Island, a 2–3 km succession of turbiditic coarse sandstones and volcanic rocks is exposed. Four…1 January, 2012 by Michael Meredith
The Southern Ocean includes the only latitude band where the ocean circles the earth unobstructed by continental boundaries. This accident of geography has profound consequences for global ocean circulation, biogeochemical…1 January, 2012 by Mark Clilverd
In order to make best use of the opportunities provided by space missions such as the Radiation Belt Storm Probes, we determine the response of complementary subionospheric radiowave propagation measurements…1 January, 2012 by Andrew Clarke, Eugene Murphy, Nadine Johnston
Since its discovery Antarctica has held a deep fascination for biologists. Extreme environmental conditions, seasonality and isolation have lead to some of the most striking examples of natural selection and…Read more on Antarctic Ecosystems: An Extreme Environment in a Changing World
1 January, 2012 by Andrew Clarke, David Pearce, Katrin Linse, Robert Larter
Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins…1 January, 2012 by Dominic Hodgson
210Pb-dated sediment cores taken from lakes on the Falkland Islands, the South Orkney Islands, and the Larsemann Hills in Antarctica were analyzed for fly ash particles to assess the temporal…