Showing 11923 items
13 April, 2010 by Michael Meredith
The Antarctic Circumpolar Current (ACC), the world’s largest oceanic flow (∼135 million cubic meters per second), is an important component of the ocean climate, as it connects the three major…1 April, 2010
Rafting is one of the important deformation mechanisms of sea ice. This process is widespread in the north Caspian Sea, where multiple rafting produces thick sea ice features, which are…Read more on A model for the consolidation of rafted sea ice
1 April, 2010 by Mai Mai Lam, Nigel Meredith, Richard Horne, Sarah Glauert, Tracy Moffat-Griffin
Energetic electrons are deposited into the atmosphere from Earth's inner magnetosphere, resulting in the production of odd nitrogen (NOx). During polar night, NOx can be transported to low altitudes, where…Read more on Origin of energetic electron precipitation >30 keV into the atmosphere
1 April, 2010 by Mark Clilverd, Mai Mai Lam
The coupling of the Van Allen radiation belts to the Earth's atmosphere through precipitating particles is an area of intense scientific interest. Currently, there are significant uncertainties surrounding the precipitating…26 March, 2010
In 2008 the temporal focus of the Palaeoclimate Modelling Intercomparison Project was expanded to include a model intercomparison for the mid-Pliocene warm period (3.29–2.97 million years ago). This project is…16 March, 2010 by Philip Trathan
Diving animals have to counter both drag and buoyancy when moving through the water column. The magnitude of these forces depends upon an animal's swim speed and current depth. Feet,…Read more on Optimal stroke frequency during diving activity in seabirds
11 March, 2010
While Antarctica is often described as a pristine environment, there is an increasing awareness of the potential threats from local pollution sources including tourist ships and emissions associated with scientific…2 February, 2010 by David Vaughan
In recent decades, seven out of twelve ice shelves around the Antarctic Peninsula (AP) have either retreated significantly or have been almost entirely lost. At least some of these retreats…1 February, 2010 by Mark Clilverd
A type of electromagnetic phenomenon has been found in the electric VLF data measured by the low Earth orbit DEMETER satellite, which was nonidentified earlier as a different class of…Read more on An unusual VLF signature structure recorded by the DEMETER satellite
1 February, 2010 by Hugh Venables
Most of the Southern Ocean is a high-nutrient, low-chlorophyll (HNLC) area. There are exceptions to this situation downstream of some of the islands, where iron from the islands or surrounding…28 January, 2010 by Peter Ward
During the austral summer of 2008, we carried out a high resolution survey of the microplankton communities along a south to north transect covering a range of environments across the…1 January, 2010 by Richard Phillips
We investigated the concentrations of 22 essential and non-essential elements among a community of Procellariiformes (and their prey) to identify the extent to which trophic position and foraging range governed…1 January, 2010 by Amelie Kirchgaessner
This paper presents results of a combined analysis of cloud observations made at the Antarctic base Faraday/Vernadsky between 1960 and 2005 and sea ice concentration from the HadISST1 data set.…Read more on An analysis of cloud observations from Vernadsky, Antarctica
1 January, 2010 by Emily Shuckburgh
Meridional cross sections of effective diffusivity in the Southern Ocean are presented and discussed. The effective diffusivity, K-eff, characterizes the rate at which mesoscale eddies stir properties on interior isopycnal…Read more on Enhancement of mesoscale eddy stirring at steering levels in the Southern Ocean
1 January, 2010 by Claire Allen, Dominic Hodgson
Analyses of a 12 m marine sediment core from Neny Fjord, Marguerite Bay, Antarctic Peninsula (68.2571°S, 66.9617°W), yield a high-resolution record of Holocene climate variability. The sediments preserve signals of…1 January, 2010
The MarQUEST (Marine Biogeochemistry and Ecosystem Modelling Initiative in QUEST) project was established to develop improved descriptions of marine biogeochemistry, suited for the next generation of Earth system models. We…Read more on Marine ecosystem models for earth systems applications: The MarQUEST experience
1 January, 2010 by Andrew Clarke
Phytoplankton assemblages from seasonally sea-ice covered Ryder Bay (Adelaide Island, Antarctica) were studied over three austral summers (2004–2007), to link sea-ice variability and environmental conditions with algal speciation. Typical of…Read more on Seasonal progression of diatom assemblages in surface waters of Ryder Bay, Antarctica
1 January, 2010 by Hilmar Gudmundsson, Robert Arthern
As simulations of 21st-century climate start to include components with longer timescales, such as ice sheets, the initial conditions for those components will become critical to the forecast. This paper…Read more on Initialization of ice-sheet forecasts viewed as an inverse Robin problem
1 January, 2010 by Pierre Dutrieux
A complex pattern of zonal currents below the thermocline has been observed in the equatorial Pacific and Atlantic Oceans. The currents have typical speeds from 10 to 15 cm s−1…Read more on Deep equatorial ocean circulation induced by a forced- dissipated Yanai beam
1 January, 2010 by Vsevolod Afanasyev
Since 1899 ringing (or banding) remained the most important source of information about migration routes, stopover sites and wintering grounds for birds that are too small to carry satellite-based tracking…Read more on Year-round tracking of small trans-Saharan migrants using light-level geolocators
1 January, 2010 by Philip Trathan
Long-distance migration enables many organisms to take advantage of lucrative breeding and feeding opportunities during summer at high latitudes and then to move to lower, more temperate latitudes for the…1 January, 2010 by Eric Wolff
The papers in this issue originate from a symposium held in Venice in November 2008 to celebrate the official end of the European Project for Ice Coring in Antarctica (EPICA).…Read more on Climate of the last million years: new insights from EPICA and other records
1 January, 2010
Glacial terminations during the late Pleistocene epoch are associated with changes in insolation. They are also punctuated by millennial-scale climate shifts, characterized by a weakening and subsequent strengthening of the…Read more on Extreme deepening of the Atlantic overturning circulation during deglaciation
1 January, 2010 by David Barnes, Claus-Dieter Hillenbrand
Collapse of the West Antarctic Ice Sheet (WAIS) would raise global sea level by similar to 3.3-5 m. Ice-sheet models and geological data suggest at least one collapse has happened…Read more on Faunal evidence for a late quaternary trans-Antarctic Seaway
1 January, 2010 by David Barnes
Aim At the height of glaciations such as the Last Glacial Maximum (LGM), benthic life on polar continental shelves was bulldozed off nearly all of the Antarctic shelf by grounded…1 January, 2010 by David Barnes, Lloyd Peck, Simon Morley
The relevance of laboratory experiments in predicting effects of climate change has been questioned, especially in Antarctica where sea temperatures are remarkably stable. Laboratory studies of Southern Ocean marine animal…1 January, 2010 by David Barnes
More so than at any previous time, there is a heightened awareness of the amount of plastic in the environment, it's spread to even remote localities and the multiple influences…1 January, 2010 by Andrew Fleming, Eugene Murphy, Jaume Forcada
There is a need to characterise the physical environment associated with Antarctic minke whale density in order to understand long-term changes in minke whale distribution and density in open waters…1 January, 2010
This paper reviews the ways in which the palaeo record of Antarctic Ice Sheet change can be used to improve understanding of contemporary ice sheet behaviour, and thus enhance predictions…1 January, 2010 by Eric Wolff
Along the EPICA Dome C ice core, we measured concentrations of different water-soluble aerosol constituents and deduced total depositional flux records. Here we present high-resolution sodium, calcium, ammonium and nitrate…1 January, 2010 by Andy Smith, Ed King, Hamish Pritchard
This review presents a perspective on recent trends in glacial geomorphological research, which has seen an increasing engagement with investigating glaciation over larger and longer timescales facilitated by advances in…Read more on Glacial geomorphology: towards a convergence of glaciology and geomorphology
1 January, 2010 by Eric Wolff, Robert Mulvaney
The Sr and Nd isotopic composition of dust extracted from recent snow layers at the top of Berkner Island ice sheet (located within the Filchner–Ronne Ice Shelf at the southern…1 January, 2010 by Thomas Bracegirdle
Marine cold air outbreaks (MCAOs) are events where cold air flows over a relatively warm sea surface. Such outbreaks are associated with severe mesoscale weather systems that are not generally…Read more on Climatology and variability of Southern Hemisphere marine cold-air outbreaks
1 January, 2010
A survey was undertaken to determine the extent of Leratiomyces ceres (syn. Stropharia aurantiaca sensu auct.) in soil surrounding apparently isolated occurrences of fungal fruit bodies on woodchip mulch. A…1 January, 2010
[1] Microzooplankton ingest a significant fraction of primary production in the ocean and thus remineralize nutrients and stimulate regenerated primary production. We synthesized observations on microzooplankton carbon-specific grazing rate, partitioning…1 January, 2010 by Guy Hillyard, Michael Thorne, Roger Worland, Melody Clark, Peter Convey
The ability of the Antarctic microarthropod Cryptopygus antarcticus (Collembola, Isotomidae) to survive low temperatures has been well studied at the physiological level, with recent investigations indicating the importance of the…1 January, 2010
There has never been a greater need for delivering timely and policy-relevant information on the magnitude and evolution of the human-disturbed carbon cycle. In this paper, we present the main…1 January, 2010 by Peter Convey
Quantitative scaling relationships among body mass, temperature and metabolic rate of organisms are still controversial, while resolution may be further complicated through the use of different and possibly inappropriate approaches…1 January, 2010 by Iain Staniland
Predictable sources of food underpin lifetime reproductive output in long lived animals. The most important foraging areas of top marine predators are therefore likely to be related to environmental features…Read more on The influence of diet on foraging habitat models: a case study using nursing fur seals
1 January, 2010 by Richard Phillips
In birds, the period spent brooding or guarding young chicks is highly variable, but such variation has seldom been studied. Previous single-year studies of Antarctic petrels Thalassoica antarctica and grey-headed…1 January, 2010 by Andrew Clarke, Michael Meredith
Dissolved iodine speciation in surface seawater at a coastal Antarctic site has been studied over a period spanning three austral summers. The sampling site is biologically productive, with a summertime…1 January, 2010 by David Pearce, Peter Convey
In a previous study, soil bacterial diversity at environmentally distinct locations on Signy Island was examined using denaturing gradient gel electrophoresis (DGGE) profiling, and a range of chemical variables in…1 January, 2010 by Lloyd Peck, Michael Thorne, Melody Clark
Background: The Antarctic clam, Laternula elliptica, is an infaunal stenothermal bivalve mollusc with a circumpolar distribution. It plays a significant role in bentho-pelagic coupling and hence has been proposed as…1 January, 2010
Early Pliocene cheilostome bryozoans are preserved in a glacigenic diamictite at Cascade Cliffs, James Ross Island, northern Antarctic Peninsula. Several different marine bryozoan genera were incorporated into the diamictite during…Read more on Early Pliocene Weddell Sea seasonality determined by bryozoans
1 January, 2010 by Andrew Clarke, Alistair Crame
Ecologists have long been fascinated by the flora and fauna of extreme environments. Physiological studies have revealed the extent to which lifestyle is constrained by low temperature but there is…1 January, 2010 by Andrew Clarke
Endothermy has evolved at least twice, in the precursors to modern mammals and birds. The most widely accepted explanation for the evolution of endothermy has been selection for enhanced aerobic…Read more on Temperature, metabolic power and the evolution of endothermy
1 January, 2010 by Mark Clilverd
Noise burst events observed at Sodankylä, Finland, in the frequency range 20–25 kHz during January–April 2005 last up to 4 s, occur more often at midnight, are associated with high…1 January, 2010
Despite clear benefits of optimal arrival time on breeding grounds, migration schedules may vary with an individual bird's innate quality, non-breeding habitat or breeding destination. Here, we show that for…Read more on Breeding latitude drives individual schedules in a trans-hemispheric migrant bird
1 January, 2010 by Peter Convey
Although its major components have been known almost since the earliest exploring expeditions, even today the terrestrial biota of Antarctica is surprisingly poorly described in detail. It is clear that…Read more on Terrestrial biodiversity in Antarctica – recent advances and future challenges
1 January, 2010 by Peter Convey
We report the establishment of two representatives of a new ecological functional group on the sub-Antarctic island of South Georgia - pollinating insects - in the form of the hoverfly…1 January, 2010 by David Herbert
Using archival photography and satellite imagery, we have analysed the rates of advance or retreat of 103 coastal glaciers on South Georgia from the 1950s to the present. Ninety-seven percent…Read more on Glacier retreat on South Georgia and implications for the spread of rats
1 January, 2010
South Georgia is a glaciated island in the South Atlantic, which provides a primary nesting site for the albatrosses and petrels of the Southern Ocean. 60% of the island is…Read more on Estimating ice thickness in South Georgia from SRTM elevation data
1 January, 2010 by Philip Trathan, Richard Phillips
Where life-history stages overlap, there is the potential for physiological conflicts that might be important in mediating carryover effects. However, our knowledge of the specific physiological mechanisms underlying carryover effects…1 January, 2010 by Teal Riley
The island of South Georgia exposes remnants of a Late Jurassic to Early Cretaceous Andean magmatic arc and marginal basin system that was compressively deformed during the mid-Cretaceous main Andean…Read more on Andean sinistral transpression and kinematic partitioning in South Georgia
1 January, 2010
The analysis of many natural time series and especially those related to ice core records often suffers from uneven sampling intervals. For fractional Brownian motion, we show that standard estimates…1 January, 2010 by Povl Abrahamsen
This paper examines the role of atmospheric forcing in modifying the pathways of riverine water on the Laptev Sea shelf, using summer-to-winter hydrographic surveys from 2007-2009. Over the two consecutive…1 January, 2010 by Jaume Forcada
Leopard seals are regular winter visitors to Bird Island, South Georgia, where they mostly prey on fur seals and penguins, and to a lesser extent on Antarctic krill and fish.…Read more on First documentation of leopard seal predation of South Georgia pintail duck
1 January, 2010 by Janet Silk, Richard Phillips
The study of long-distance migration provides insights into the habits and performance of organisms at the limit of their physical abilities. The Arctic tern Sterna paradisaea is the epitome of…Read more on Tracking of Arctic terns Sterna paradisaea reveals longest animal migration
1 January, 2010 by Peter Convey
Coal Nunatak is an ice-free inland nunatak located on southern Alexander Island, adjacent to the west coast of the Antarctic Peninsula. Situated close to the Antarctic continent, it is characterized…Read more on Life history strategy of Lepraria borealis at an Antarctic inland site, Coal Nunatak
1 January, 2010 by Simon Morley
Ocean acidification, or the lowering of seawater pH, is caused by sequestration of atmospheric CO2 into the oceans. This study investigated the effects of present-day pH 8.0, predicted ocean surface…1 January, 2010
The Ronne Polynya is a coastal polynya, a region of thin ice or open water in sea ice, caused by the offshore transport of the ice by strong winds from…Read more on Ocean-atmosphere heat fluxes at the Ronne Polynya, Antarctica
1 January, 2010 by Eric Wolff
Recent progress in the reconstruction of atmospheric CO2 records from Antarctic ice cores has allowed for the documentation of natural CO2 variations on orbital time scales over the last up…1 January, 2010
This study examines the long-range dependency, climate noise characteristics, and nonlinear temperature trends of eight Antarctic stations from the Reference Antarctic Data for Environmental Research (READER) dataset. Evidence is shown…Read more on Long-range dependence and climate noise characteristics of Antarctic temperature data
1 January, 2010 by Mervyn Freeman
There is substantial interest in the effect of human mobility patterns on opportunistic communications. Inspired by recent work revisiting some of the early evidence for a Lévy flight foraging strategy…1 January, 2010 by Dominic Hodgson, Peter Fretwell, Stephen Roberts
We present new isobases constraining the Holocene isostatic uplift of the South Shetland Islands, northern Antarctic Peninsula, based on evidence from raised shorelines. Holocene shorelines were described and surveyed at…1 January, 2010
Emissions of CO2 are the main contributor to anthropogenic climate change. Here we present updated information on their present and near-future estimates. We calculate that global CO2 emissions from fossil…1 January, 2010 by Joanne Johnson
This paper presents new lichenometric population data from the Antarctic Peninsula (67°S), and describes a new approach to lichen growth-rate calibration in locations where dated surfaces are extremely rare. We…1 January, 2010 by Eugene Murphy, Geraint Tarling, Melody Clark, Will Goodall-Copestake
The Antarctic krill, Euphausia superba, is an abundant and key species found in the Southern Ocean that forms dense, discrete swarms. Despite over three decades of research on Antarctic krill,…Read more on Swarms of diversity at the gene cox1 in Antarctic krill
1 January, 2010 by Huw Griffiths
The remote and hostile Southern Ocean is home to a diverse and rich community of life that thrives in an environment dominated by glaciations and strong currents. Marine biological studies…1 January, 2010 by Victoria Peck
Increased fluxes of ice-rafted detritus (IRD) from European ice sheets have been documented some 1000-1500 years before the arrival of Laurentide Ice Sheet (LIS)-sourced IRD during Heinrich (H) events. These…1 January, 2010 by Martin Miller
To investigate the formation and early evolution of the lunar mantle and crust we have analysed the oxygen isotopic composition, titanium content and modal mineralogy of a suite of lunar…1 January, 2010
Introduction: The diurnal rhythm of saliva cortisol and its association to adaptation, performance and health were examined in personnel over-wintering at two British Antarctic stations. Methods: In total, 55 healthy…1 January, 2010 by Richard Phillips
Most seabirds die outside the breeding season, but understanding the key factors involved is hampered by limited knowledge of nonbreeding distributions. We used miniature geolocating loggers to examine the movements…1 January, 2010 by Philip Trathan
The nature of how behaviour at one time step influences the next is of great interest to behavioural ecologists, but rarely used for comparisons between animals. Time depth recorders (TDR)…1 January, 2010 by Philip Trathan
Recording the activity of animals as they migrate or forage has proven hugely advantageous to understanding how animals use their environment. Where animals cannot be directly observed, the problem remains…1 January, 2010 by Roger Worland
The process of organismal freezing in the Antarctic limpet, Nacelle concinna, is complicated by molluscan biology. Internal ice formation is, in particular, mediated by two factors: (a) the provision of…Read more on Freezing in the Antarctic limpet, Nacella concinna
1 January, 2010 by Michael Meredith
The use of dissolved Al as a tracer for oceanic water masses and atmospheric dust deposition of biologically important elements, such as iron, requires the quantitative assessment of its sources…1 January, 2010 by Hugh Venables
The Crozet Plateau is an area of interest as it is a region of the Southern Ocean where annual primary productivity is relatively high. We describe spatial and temporal variations…1 January, 2010
The longitudinal variability of the semidiurnal tide in the Antarctic upper mesosphere is investigated by comparison of observations from two radars at approximately opposite sides of Antarctica. Under the assumption…Read more on A new perspective on the longitudinal variability of the semidiurnal tide
1 January, 2010 by Oliver Marsh
Twelve years of horizontal wind data from the Scott Base MF radar and the Halley SuperDARN radar recorded between January 1996 and December 2007 are analysed to study the interannual…1 January, 2010 by Claire Waluda, Jaume Forcada, Philip Trathan, Simeon Hill
The purpose of ecosystem monitoring programs is to indicate the state of ecosystems and whether they have been impacted by activities such as fishing. This paper discusses a range of…Read more on Using ecosystem monitoring data to detect impacts
1 January, 2010 by Claus-Dieter Hillenbrand, Robert Larter
A major trough ("Belgica Trough") eroded by a palaeo-ice stream crosses the continental shelf of the southern Bellingshausen Sea (West Antarctica) and is associated with a trough mouth fan ("Belgica…1 January, 2010 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
Reliable dating of glaciomarine sediments deposited on the Antarctic shelf since the Last Glacial Maximum (LGM) is challenging because of the rarity of calcareous (micro-) fossils and the recycling of…1 January, 2010 by Chester Sands, Dominic Hodgson, Peter Convey, Sandra McInnes, Sandra McInnes
Very little is known about the higher latitude inland biology of continental Antarctica. In this paper we describe the limnology and biology of the Dufek Massif, using a range of…Read more on The limnology and biology of the Dufek Massif, Transantarctic Mountains 82° South
1 January, 2010 by Dominic Hodgson, Louise Sime
The Southern Hemisphere westerly winds affect the exchange of carbon dioxide between the ocean and atmosphere. Climate reconstructions from the southern mid-latitudes may reveal variability in the strength and position…1 January, 2010 by David Pearce
Glacier surfaces support unique microbial food webs dominated by organic and inorganic debris called 'cryoconite'. Observations from Longyearbreen, Spitsbergen, show how these aggregate particles can develop an internal structure following…1 January, 2010 by Kevin Newsham
Solute yields, laboratory dissolution data and both chemical and isotopic markers of rock weathering reactions are used to characterise the biogeochemistry of glacial meltwaters draining a maritime Antarctic glacier. We…1 January, 2010 by Guy Hillyard, Lloyd Peck, Melody Clark
The extent to which genetic divergence can occur in the absence of physical barriers to gene flow is currently one of the most controversial topics in evolutionary biology, with implications…1 January, 2010 by Jaume Forcada
Although heterozygosity-fitness correlations (HFCs) are widely reported in the literature, most studies use too few markers to allow the proximate mechanisms to be convincingly resolved. Two competing hypotheses have been…1 January, 2010 by Jaume Forcada, Philip Trathan
Most studies of heterozygosity-fitness correlations (HFCs) in natural populations relate to fitness traits expressed early in life, whereas traits that are often more difficult to measure such as longevity and…1 January, 2010 by Rachel Cavanagh
Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species…Read more on The impact of conservation on the status of the world’s vertebrates
1 January, 2010 by Eric Wolff
Ice core evidence indicates that even though atmospheric CO2 concentrations did not exceed 300 ppm at any point during the last 800 000 years, East Antarctica was at least 3–4…1 January, 2010 by Paul Holland
Greenland is losing ice through glaciers that flow into deep fjords. New observations highlight the important fjord processes that supply warm ocean waters to the melting glaciers, and thereby affect…1 January, 2010 by Kevin Hughes, Peter Convey, Rolf Maslen
Antarctic terrestrial ecosystems currently include very few non-native species, due to the continent’s extreme isolation from other landmasses. However, the indigenous biota is vulnerable to human-mediated introductions of non-native species.…1 January, 2010 by Kevin Hughes
Under the Antarctic Treaty System, environmental monitoring is a legal obligation for signatory nations and an essential tool for managers attempting to minimize local human impacts, but is it given…Read more on How committed are we to monitoring human impacts in Antarctica?
1 January, 2010 by Kevin Hughes, Peter Convey
Invasions by non-indigenous species are amongst the greatest threats to global biodiversity, causing substantial disruption to, and sometimes local extinction of, individual species and community assemblages which, in turn, can…1 January, 2010 by Kevin Hughes
Antarctic ecosystems are at risk from the introduction of invasive species. The first step in the process of invasion is the transportation of alien species to Antarctic in a viable…Read more on Impact of anthropogenic transportation to Antarctica on alien seed viability