Showing 13487 items
1 October, 2013 by Ed King
On RADARSAT imagery, the southern margin of the onset zone of Bindschadler Ice Stream, West Antarctica, manifests a multi-banded feature, with brightness varying across the bands and oscillating along each…1 October, 2013 by Kevin Hughes
A single colony of the non-native grass Poa pratensis L., which was introduced inadvertently to Cierva Point, Antarctic Peninsula, during the 1954–1955 season, was still present during a survey in…1 October, 2013 by Richard Phillips
Populations of flesh-footed shearwaters on Lord Howe Island, Tasman Sea, have declined recently, with mortality in longline fisheries likely to be one of the major causes. It is therefore imperative…1 October, 2013 by Richard Phillips
Although mercury bio-amplifies through the food chain and accumulates in top predators, mercury concentrations in tissues of the wandering albatross are greater than in any other vertebrate, including closely related…1 October, 2013 by Jennifer Jackson
Regional populations of bottlenose dolphins (Tursiops truncatus) around New Zealand are genetically isolated from each other and the species was recently classified as nationally endangered based on relatively small population…1 October, 2013 by Adrian Jenkins
Thermodynamic flowline and plume models for the ice-shelf/ocean system simplify the ice and ocean dynamics sufficiently to allow extensive exploration of parameters affecting ice-sheet stability while including key physical processes.…1 October, 2013 by Melody Clark
Polar marine ecosystems have global ecological and economic importance because of their unique biodiversity and their major role in climate processes and commercial fisheries, among others. Portugal and Spain have…1 October, 2013 by Ed King, Paul Holland
Antarctic ice shelves are fed primarily by the glaciers flowing into them. Downstream of promontories separating these glaciers, supercooled water can rise and freeze into suture zones, leading to the…26 September, 2013 by Andrew Fleming, Adrian Jenkins, David Vaughan, Hugh Corr, Paul Holland, Pierre Dutrieux
By thinning and accelerating, West Antarctic ice streams are contributing about 10% of the observed global sea level rise. Much of this ice loss is from Pine Island Glacier, which…Read more on Pine Island Glacier ice shelf melt distributed at kilometre scales
26 September, 2013 by Claus-Dieter Hillenbrand
Radiocarbon and uranium-thorium dating results are presented from a genus of calcitic Antarctic cold-water octocorals (family Coralliidae), which were collected from the Marie Byrd Seamounts in the Amundsen Sea (Pacific…23 September, 2013 by Ingrid Cnossen
The nondipolar portions of the Earth's main magnetic field constitute substantial differences between the two hemispheres. Beside the magnetic flux densities and patterns being different in the Northern Hemisphere (NH)…22 September, 2013 by Paul Rodhouse
Doryteuthis gahi (Orbigny, 1835) is a relatively small squid typically attaining 13–17 cm mantle length that inhabits the shelves around the southern tip of South America from southern Peru in…22 September, 2013 by Claire Waluda, Paul Rodhouse
Illex argentinus, a close relative of the other North Atlantic Illex species, concentrates on the Patagonian shelf edge and spreads over the shelf from Southern Brazil to the Falkland Islands.…22 September, 2013 by Claire Waluda, Paul Rodhouse
Dosidicus gigas (Humboldt or jumbo squid) (Orbigny, 1835) is the largest ommastrephid squid, reaching up to 1.2m mantle length and 65kg in weight. This pelagic squid is endemic to the…20 September, 2013 by Tracy Moffat-Griffin
Abundant short‒period, small‒scale gravity waves have been identified in the mesosphere and lower thermosphere over Halley, Antarctica, via ground‒based airglow image data. Although many are observed as freely propagating at…19 September, 2013 by Michael Meredith
Diapycnal mixing (across density surfaces) is an important process in the global ocean overturning circulation. Mixing in the interior of most of the ocean, however, is thought to have a…17 September, 2013 by Richard Phillips
Investigating the foraging ecology of seabirds is especially challenging given their wide-ranging movements and the practical difficulties of obtaining unbiased information on their feeding behavior. Despite the development of animal-borne…15 September, 2013 by Claire Waluda, Iain Staniland
Between November 1989 and March 2013, 1033 Antarctic fur seals Arctocephalus gazella were observed entangled in marine debris at Bird Island, South Georgia. The majority of entanglements involved plastic packaging…Read more on Entanglement of Antarctic fur seals at Bird Island, South Georgia
13 September, 2013 by David Pearce
Deep water samples (ca. 4,200 m) were taken from two hydrologically-similar sites around the Crozet islands with highly contrasting surface water productivities. Site M5 was characteristic of high productivity waters…13 September, 2013 by Hugh Corr
Ice shelves play a key role in the mass balance of the Antarctic ice sheets by buttressing their seaward-flowing outlet glaciers; however, they are exposed to the underlying ocean and…11 September, 2013
Climate change poses challenges for decision makers across society, not just in preparing for the climate of the future but even when planning for the climate of the present day.…Read more on Mapping climate change in European temperature distributions
9 September, 2013 by Dominic Hodgson, Peter Convey
Annual temperatures on the Antarctic Peninsula, one of the most rapidly warming regions on Earth, have risen by up to 0.56°C per decade since the 1950s [1]. Terrestrial and marine…Read more on Plants and soil microbes respond to recent warming on the Antarctic Peninsula
8 September, 2013 by Jaume Forcada
Many species have been heavily exploited by man leading to local extirpations, yet few studies have attempted to unravel subsequent recolonization histories. This has led to a significant gap in…6 September, 2013 by Dominic Hodgson, David Pearce, Michael Thorne
Since the first descriptions of Antarctic subglacial lakes, there has been a growing interest and awareness of the possibility that life will exist and potentially thrive in these unique and…Read more on Preliminary analysis of life within a former subglacial lake sediment in Antarctica
5 September, 2013 by Markus Frey
The first measurements of atmospheric nitric oxide (NO) along with observations of ozone (O3), hydroperoxides (H2O2 and MHP) and snow nitrate (NO3–) on the West Antarctic Ice Sheet (WAIS) were…3 September, 2013 by Jaume Forcada
Brucellosis is a worldwide infectious zoonotic disease caused by Gram-negative bacteria of the genus Brucella, and Brucella infections in marine mammals were first reported in 1994. A serosurvey investigating the…3 September, 2013 by Philip Trathan
Biogenic influences on the composition and characteristics of aerosol were investigated on Bird Island (54°00' S, 38°03' W) in the South Atlantic during November and December 2010. This remote marine…Read more on Sub-Antarctic marine aerosol: significant contributions from biogenic sources
1 September, 2013 by Teal Riley
Primitive rocks that are related to continental flood basalts are rare, but often reveal crucial information on the ultimate sources of these huge outpourings of mantle-derived magma. Here we present…1 September, 2013 by Alexander Tate, Philip Leat
New multibeam bathymetry data are presented for the South Sandwich intra-oceanic arc which occupies the small Sandwich plate in the South Atlantic, and is widely considered to be a simple…1 September, 2013
Boundary-layer measurements from the Brunt Ice Shelf, Antarctica are analyzed to determine flux–profile relationships. Dimensionless quantities are derived in the standard approach from estimates of wind shear, potential temperature gradient,…Read more on Investigation of the stable atmospheric boundary layer at Halley Antarctica
1 September, 2013 by Eric Wolff
Sea ice is an important component of the Earth system with complex dynamics imperfectly documented from direct observations, which are primarily limited to the last 40 years. Whereas large amplitude…1 September, 2013 by Hugh Corr, Robert Arthern
Translating satellite measurements of ice sheet volume change into sea level contribution requires knowledge of the profile of density as a function of depth within the ice sheet, and how…Read more on Inversion for the density-depth profile of polar firn using a stepped-frequency radar
1 September, 2013 by Gareth Chisham, Mervyn Freeman
The Super Dual Auroral Radar Network (SuperDARN) is a network of HF radars used to study phenomena in the Earth's magnetosphere, ionosphere, and upper atmosphere. Phenomena in the upper mesosphere…1 September, 2013 by David Pearce, Peter Convey
A range of small- to moderate-scale studies of patterns in bacterial biodiversity have been conducted in Antarctica over the last two decades, most suggesting strong correlations between the described bacterial…Read more on Spatial pattern in Antarctica: what can we learn from Antarctic bacterial isolates?
1 September, 2013 by Michael Thorne, Melody Clark
Understanding the environmental responses of an invasive species is critical in predicting how ecosystem composition may be transformed in the future, especially under climate change. In this study, Crassostrea gigas,…1 September, 2013 by Andrew Clarke
The metabolic status of dinosaurs has long been debated but remains unresolved as no consistent picture has emerged from a range of anatomical and isotopic evidence. Quantitative analysis of dinosaur…Read more on Dinosaur energetics: setting the bounds on feasible physiologies and ecologies
1 September, 2013 by Hugh Venables, Michael Meredith
The extent, duration, and seasonality of sea ice and glacial discharge strongly influence Antarctic marine ecosystems. Most organisms' life cycles in this region are attuned to ice seasonality. The annual…Read more on West Antarctic Peninsula: An ice-dependent coastal marine ecosystem in transition
1 September, 2013 by Roger Worland, Peter Convey
The collembolan Cryptopygus antarcticus Willem is potentially exposed to habitat salinities equal to (or greater than) sea water, as a result of sea spray, drying of littoral habitats, dispersal or…1 September, 2013 by Adrian Jenkins, David Vaughan, Pierre Dutrieux, Robert Larter
Ice shelves are critical features in the debate about West Antarctic ice sheet change and sea level rise, both because they limit ice discharge and because they are sensitive to…1 September, 2013 by Mervyn Freeman
We present a survey of medium-scale traveling ionospheric disturbances (MSTIDs) observed by a Super Dual Auroral Radar Network HF radar located in the Falkland Islands between May 2010 and April…1 September, 2013 by Emilie Capron
Air and water stable isotope measurements from four Greenland deep ice cores (GRIP, GISP2, NGRIP and NEEM) are investigated over a series of Dansgaard–Oeschger events (DO 8, 9 and 10),…1 September, 2013 by Andrew Orr, Gareth Marshall, Scott Hosking, John Turner, Tony Phillips
In contrast to earlier studies, the authors describe the climatological deep low pressure system that exists over the South Pacific sector of the Southern Ocean, referred to as the Amundsen–Bellingshausen…1 September, 2013 by Pierre Dutrieux
The large and complex Getz Ice Shelf extends along nearly half of the West Antarctic coastline in the Amundsen Sea, and is exposed to a more variable ocean environment than…Read more on Getz Ice Shelf melting response to changes in ocean forcing
1 September, 2013 by Chester Sands, David Barnes, David Pearce, Huw Griffiths
In the Southern Ocean, that is areas south of the Polar Front, long-term oceanographic cooling, geographic separation, development of isolating current and wind systems, tectonic drift and fluctuation of ice…1 September, 2013 by Katrin Linse
Microsatellite loci have been developed for three undescribed species discovered at hydrothermal vents on the East Scotia Ridge (ESR) in the Southern Ocean: a yeti crab, Kiwa sp. (Kiwaidae), a…1 September, 2013 by Michael Meredith
The West Antarctic Peninsula (WAP) is home to large breeding colonies of the ice-dependent Antarctic Adélie penguin (Pygoscelis adeliae). Although the entire inner continental shelf is highly productive, with abundant…31 August, 2013
U-Pb zircon ion-microprobe geochronology, whole rock geochemistry and feldspar Pb and Sm-Nd isotopic analyses carried out on granitoid rocks along a transect across the Nabitah fault zone suggest that it…28 August, 2013 by Hugh Corr
We analyze data acquired by the CryoSat-2 interferometric radar altimeter and demonstrate its novel capability to track topographic features on the Antarctic Ice Sheet. We map the perimeter and depth…Read more on Three-dimensional mapping by Cryosat 2 of subglacial lake volumes
21 August, 2013 by Simeon Hill, Tony Phillips
Antarctic krill is a cold water species, an increasingly important fishery resource and a major prey item for many fish, birds and mammals in the Southern Ocean. The fishery and…21 August, 2013 by Michael Thorne, Melody Clark
Background The Ice krill, Euphausia crystallorophias is one of the species at the base of the Southern Ocean food chain. Given their significant contribution to the biomass of the Southern…19 August, 2013 by Claus-Dieter Hillenbrand
This paper presents a glacial geomorphological map of over 17,000 landforms on the bed of a major palaeo-ice stream in Marguerite Bay, western Antarctic Peninsula. The map was compiled using…Read more on Glacial geomorphology of Marguerite Bay Palaeo-Ice stream, western Antarctic Peninsula
11 August, 2013
At the Earth’s surface, heat fluxes from the interior1 are generally insignificant compared with those from the Sun and atmosphere2, except in areas permanently blanketed by ice. Modelling studies show…7 August, 2013 by Katrin Linse
The phylogeny of the superfamily Chirostyloidea (Decapoda: Anomura) has been poorly understood owing to limited taxon sampling and discordance between different genes. We present a nine-gene dataset across 15 chirostyloids,…2 August, 2013 by Philip Trathan
Post-breeding migration in land-based marine animals is thought to offset seasonal deterioration in foraging or other important environmental conditions at the breeding site. However the inter-breeding distribution of such animals…Read more on A space oddity: Geographic and specific modulation of migration in Eudyptes penguins
1 August, 2013
The marine copepod, Calanus finmarchicus, is a crucial component of the pelagic food web in the North Atlantic and peripheral seas where it is a major player in biogeochemical cycles…1 August, 2013 by Katrin Linse
Large cetacean carcasses at the deep-sea floor, known as ‘whale falls’, provide a resource for generalist-scavenging species, chemosynthetic fauna related to those from hydrothermal vents and cold seeps, and remarkable…Read more on The discovery of a natural whale fall in the Antarctic deep sea
1 August, 2013 by Emilie Capron, Eric Wolff
An accurate and coherent chronological framework is essential for the interpretation of climatic and environmental records obtained from deep polar ice cores. Until now, one common ice core age scale…1 August, 2013 by Carlos Martin Garcia
The Fourth IPCC Assessment Report concluded that ice sheet flow models, in their current state, were unable to provide accurate forecast for the increase of polar ice sheet discharge and…Read more on Capabilities and performance of Elmer/Ice, a new-generation ice sheet model
1 August, 2013 by Kevin Hughes
The footprint of human activities within Antarctica is increasing, making it essential to consider whether current conservation/protection of environmental and scientific values is adequate. The Antarctic protected area network has…1 August, 2013 by Katrin Linse
Eleven specimens representing two hippolytid genera, EualusThallwitz, 1892 and LebbeusWhite, 1847 were sampled recently from the Scotia Sea (1517–2598 m). Seven specimens are described and illustrated as Eualus amandae sp.…1 August, 2013 by Lloyd Peck, Simon Morley
At all but the lowest latitudes, photoperiod varies through the year, resulting in seasonal variation in coastal primary productivity. This leads to a pronounced seasonality in the physiology of most…1 August, 2013 by Lloyd Peck
Growth rates in Antarctic marine ectotherms have been demonstrated to be slowed by two to five times compared to shallow-water temperate species, with no previous reports for octocorals. Here growth…1 August, 2013
Aim In the Northern Hemisphere, bird migration from the tropic to the temperate zone in spring is thought to proceed at a rate determined in large part by local phenology.…Read more on Phenological matching across hemispheres in a long-distance migratory bird
1 August, 2013 by Geraint Tarling, Ryan Saunders
Euphausiids are an important component of the northern North Atlantic ecosystem and several species are found in the Irminger Sea. However, data on euphausiids in this region are few, particularly…1 August, 2013 by Adrian Jenkins
The recent retreat and speedup of outlet glaciers, as well as enhanced surface melting around the ice sheet margin, have increased Greenland's contribution to sea level rise to 0.6±0.1 mm/yr…1 August, 2013 by Emilie Capron, Eric Wolff
The deep polar ice cores provide reference records commonly employed in global correlation of past climate events. However, temporal divergences reaching up to several thousand years (ka) exist between ice…1 August, 2013 by Roger Worland
This study compares the composition and biophysical properties of lipids in non-diapausing and diapausing fifth instar larvae of Ostrinia nubilalis Hubn. (Lepidoptera: Crambidae). The majority of fat body lipids in…30 July, 2013 by Philip Leat
An international 3-day meeting in which participants discussed geodynamic and multidisciplinary topics related to the evolution of the Scotia Arc was held at the Andalucía Institute of Earth Sciences (Spanish…27 July, 2013 by Mervyn Freeman
This study presents a nonlinear spatio-temporal analysis of 1167 station temperature records from the United States Historical Climatology Network covering the period from 1898 through 2008. We use the Empirical…Read more on A spatiotemporal analysis of U.S. station temperature trends over the last century
22 July, 2013 by David Barnes
The recent collapse of the Antarctic Larson ice shelves revealed a slow growing benthic community on the seabed below. But a revisit just four years later revealed rapid growth of…Read more on Marine biology: new light on growth in the cold
22 July, 2013 by Teal Riley
Earth history is punctuated by events during which large volumes of predominantly mafic magmas were generated and emplaced by processes that are generally accepted as being, unrelated to ‘normal’ sea-floor…21 July, 2013 by Claus-Dieter Hillenbrand
The East Antarctic ice sheet is believed to be Earth's most stable ice sheet. Changes in geochemical composition of offshore sediments suggest that its margin repeatedly retreated by at least…16 July, 2013 by Jaume Forcada, Michael Thorne
High-density SNP arrays developed for humans and their companion species provide a rapid and convenient tool for generating SNP data in closely-related non-model organisms, but have not yet been widely…12 July, 2013
Macrozooplankton are an important link between higher and lower trophic levels in the oceans. They serve as the primary food for fish, reptiles, birds and mammals in some regions, and…Read more on Distribution of known macrozooplankton abundance and biomass in the global ocean
5 July, 2013 by Eric Wolff
Snow and ice play their most important role in the nitrogen cycle as a barrier to land–atmosphere and ocean–atmosphere exchanges that would otherwise occur. The inventory of nitrogen compounds in…5 July, 2013 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
We present results of a multi-proxy study on marine sediment core JR179-PC466 recovered from the crest of a sediment drift off the West Antarctic Peninsula at approximately 2300 m water…1 July, 2013 by Robert Larter
Submarine gullies are common features of high latitude continental slopes and, over the last decade, have been shown to play a key role in continental margin evolution, submarine erosion, downslope…1 July, 2013 by Mark Belchier
The study of spatial and temporal distribution and diversity of ichthyoplankton (fish eggs and larvae) can provide fisheries-independent information on the population dynamics and recruitment processes of marine fish species.…1 July, 2013 by Lloyd Peck, Michael Thorne, Melody Clark
Future oceans are predicted to contain less oxygen than at present. This is because oxygen is less soluble in warmer water and predicted stratification will reduce mixing. Hypoxia in marine…Read more on Hypoxia impacts large adults first: consequences in a warming world
1 July, 2013 by Markus Frey
Here we report the measurement of the comprehensive isotopic composition (δ15N, Δ17O and δ18O) of nitrate at the air–snow interface at Dome C, Antarctica (DC, 75°06' S, 123°19' E), and…1 July, 2013 by Huw Griffiths, Katrin Linse, Mark Belchier, Rowan Whittle, Stephen Roberts
Recent scientific interest following the “discovery” of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent…1 July, 2013 by Adrian Jenkins, Paul Holland, Satoshi Kimura
Several different classes of ocean model are capable of representing floating glacial ice shelves. We describe the incorporation of ice shelves into Fluidity-ICOM, a nonhydrostatic finite-element ocean model with the…1 July, 2013 by Jonathan Kingslake
We explore a mathematical model that couples together a thermomechanically evolving subglacial channel, distributed cavity drainage, and basal sliding along a subglacial flood path fed by a jökulhlaup lake. It…Read more on Modelling the coupling of flood discharge with glacier flow during jökulhlaups
1 July, 2013 by Andrew Orr, Gareth Marshall, John Turner
The scientific literature portrays a temporally invariant spatial relationship between the phase of the southern annular mode (SAM) and the sign of surface air temperature (SAT) anomalies across Antarctica. However,…1 July, 2013 by Hilmar Gudmundsson, Richard Hindmarsh, Richard Hindmarsh
Predictions of marine ice-sheet behaviour require models able to simulate grounding-line migration. We present results of an intercomparison experiment for plan-view marine ice-sheet models. Verification is effected by comparison with…1 July, 2013 by Peter Convey
During the austral summer of 2006–07, abundant Diptera were found in the sewage system of the Base Científica Antártica Artigas on King George Island. These are here identified as Trichocera…Read more on First record of Trichoceridae (Diptera) in the maritime Antarctic
1 July, 2013 by Peter Ward, Richard Phillips, Sally Thorpe
Shifts in the diet of top predators can be linked to changes in environmental conditions. In this study, we tested relationships between environmental variation and seasonal changes in diet of…28 June, 2013
The International Bathymetric Chart of the Southern Ocean (IBCSO) Version 1.0 is a new digital bathymetric model (DBM) portraying the seafloor of the circum-Antarctic waters south of 60° S. IBCSO…28 June, 2013 by Nigel Meredith, Richard Horne
The origin of plasmaspheric hiss, the electromagnetic emission responsible for the gap between the inner and outer radiation belts, has been debated for over four decades. Recently, a new theory…Read more on Global statistical evidence for chorus as the embryonic source of plasmaspheric hiss
26 June, 2013 by Mark Clilverd
The results of the first 18 months of the PLASMON project are presented. We have extended our three, existing ground-based measuring networks, AWDANet (VLF/whistlers), EMMA/SANSA (ULF/FLRs), and AARDDVARK (VLF/perturbations on…Read more on The plasmasphere during a space weather event: first results from the PLASMON project
26 June, 2013 by Terri Souster, Lloyd Peck, Melody Clark, Terri Souster
Juvenile stages are often thought to be less resistant to thermal challenges than adults, yet few studies make direct comparisons using the same methods between different life history stages. We…19 June, 2013 by Andrew Clarke
There is no generally accepted value for the lower temperature limit for life on Earth. We present empirical evidence that free-living microbial cells cooling in the presence of external ice…19 June, 2013 by Eric Wolff
Although the Arctic occupies less than 5% of the Earth's surface, it includes some of the strongest positive feedbacks in the climate system. Reconstructing the climate history of the Quaternary…Read more on Paleoclimate, Paleoclimate history of the Arctic
19 June, 2013 by Robert Mulvaney
Electrical measurements of ice cores are used to obtain high time resolution records of past climate. The electrical conductivity method is sensitive to the acidity of the ice. The dielectric…