Showing 11923 items
1 January, 2011
The diets of Antarctic toothfish Dissostichus mawsoni and Patagonian toothfish Dissostichus eleginoides were examined around the South Sandwich Islands in the Southern Ocean, one of few regions with overlapping populations…1 January, 2011 by Dominic Hodgson, Stephen Roberts
The recent disintegration of Antarctic Peninsula ice shelves, and the associated accelerated discharge and retreat of continental glaciers, has highlighted the necessity of quantifying the current rate of Antarctic ice…1 January, 2011 by Howard Roscoe
Previous work showed a near-continuous increase in stratospheric water vapour between the 1950s and 1990s from a variety of instruments, without recourse to fits between instruments. We reassess the trend…Read more on Revisiting the lower stratospheric water vapour trend from the 1950s to 1970s
1 January, 2011 by Andy Smith, Ed King, Hugh Corr, Richard Hindmarsh, Richard Hindmarsh
We analyze Holocene ice flow using global positioning system and radio-echo sounding data acquired near the Amundsen-Weddell ice divide, between Pine Island Glacier and the Institute Ice Stream, West Antarctica.…Read more on Holocene stability of the Amundsen-Weddell ice divide, West Antarctica
1 January, 2011
Understanding the connectivity between breeding and nonbreeding populations of migratory birds is fundamental to our knowledge of biological phenomena such as population dynamics and dispersal. Moreover, our ability to quantify…1 January, 2011
Surface cross-stream eddy diffusion in the Southern Ocean is estimated by monitoring dispersion of particles numerically advected with observed satellite altimetry velocity fields. To gain statistical significance and accuracy in…Read more on Mean-flow and topographic control on surface eddy-mixing in the Southern Ocean
1 January, 2011 by Jean-Baptiste Sallee
The divergence of the eddy mass flux in the surface layer of the Southern Ocean makes an important contribution to subduction of fluid through the base of the mixed layer.…Read more on Parameterization of eddy-induced subduction in the Southern Ocean surface-layer
1 January, 2011
We use the 3-D FinROSE chemistry transport model (CTM) and Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) observations to study connections between atmospheric dynamics and middle atmospheric NOx (NOx =…1 January, 2011
The question of whether Pliocene climate was warm enough to support a substantial vegetation cover on Antarctica is of great significance to the ongoing and controversial debate on the stability…1 January, 2011
Variscan Central Iberian Zone lamprophyre dikes cut synorogenic to late orogenic peraluminous S-type granitoids marking an important shift in regional tectonic regime from earlier, 350-290 Ma, extension-related crustal melting to…1 January, 2011 by Claire Allen, Geraint Tarling, Sophie Fielding
A compilation of more than 30 studies shows that adult Antarctic krill (Euphausia superba) may frequent benthic habitats year-round, in shelf as well as oceanic waters and throughout their circumpolar…1 January, 2011 by Jonathan Shanklin
1 January, 2011 by Richard Horne
The outer radiation belt is often enhanced during storms while the inner belt is usually considered to be unaffected by geomagnetic activity. During the most recent Halloween superstorms, the extreme…Read more on Profound change of the near-Earth radiation environment caused by solar superstorms
1 January, 2011 by Emily Shuckburgh
The modulation of air-sea heat fluxes by geostrophic eddies due to the stirring of temperature at the sea surface is discussed and quantified. It is argued that the damping of…Read more on Mixed layer lateral eddy fluxes mediated by air-sea interaction
1 January, 2011 by Eric Wolff, Louise Sime
The resemblance of the orbitally filtered isotope signal from the past 340 kyr in Antarctic ice cores to Northern Hemisphere summer insolation intensity has been used to suggest that the…1 January, 2011 by Hugh Corr, Louise Sime, Richard Hindmarsh, Richard Hindmarsh
We present a novel automated processing method for obtaining layer dip from radio-echo sounding (RES) data. The method is robust, easily applicable and can be used to process large (several…Read more on Automated processing to derive dip angles of englacial radar reflectors in ice sheets
1 January, 2011 by David Barnes, Lloyd Peck
Significant warming has been observed in every ocean, yet our ability to predict the consequences of oceanic warming on marine biodiversity remains poor. Experiments have been severely limited because, until…Read more on Turning on the heat: ecological response to simulated warming in the sea
1 January, 2011
Late Miocene (c. 13-5 Ma) volcanic sequences of the Hallett Volcanic Province (HVP) crop out along > 250 km of western Ross Sea coast in northern Victoria Land. Eight primary…1 January, 2011 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
The Amundsen Sea Embayment (ASE) drains approximately 35% of the West Antarctic Ice Sheet (WAIS) and is one of the most rapidly changing parts of the cryosphere. In order to…Read more on Deglacial history of the West Antarctic Ice Sheet in the western Amundsen Sea Embayment
1 January, 2011
The study of Glacial Isostatic Adjustment (GIA) is gaining an increasingly im-portant role within the geophysical community. Understanding the response of the Earth to loading is crucial in various contexts,…Read more on A benchmark study for glacial-isostatic adjustment codes
1 January, 2011
The 2007 International Polar Year (IPY) in the Antarctic was distinguished by strong regional and seasonal ice-atmosphere-ocean anomalies associated with an overall weakening of the prevailing westerly circulation. Here we…1 January, 2011 by Iain Staniland, Jaume Forcada
We compared Antarctic fur seals Arctocephalus gazella breeding at 2 contrasting sites on South Georgia: one high density colony at Bird Island and one lower density colony at Cooper Bay.…1 January, 2011 by Robert Mulvaney
Ice-core records of climate from Greenland and Antarctica show asynchronous temperature variations on millennial timescales during the last glacial period(1). The warming during the transition from glacial to interglacial conditions…1 January, 2011
Rhyolite eruptions in Iceland mostly take place at long-lived central volcanoes, examples of which are found associated with each of the present-day rift-zone ice caps. Subglacial eruptions at Kerlingarfjöll central…Read more on Explosive rhyolite tuya formation: classic examples from Kerlingarfjoll, Iceland
1 January, 2011 by Katrin Linse
Many members of the benthic fauna of the Antarctic continental shelf share close phylogenetic relationships to the deep-sea fauna adjacent to Antarctica and in other ocean basins. It has been…1 January, 2011 by Lloyd Peck
This review describes outcomes of a 2010 horizon-scanning exercise building upon the first exercise conducted in 2009. The aim of both horizon scans was to identify emerging issues that could…Read more on A horizon scan of global conservation issues for 2011
1 January, 2011 by Richard Horne
Effects of density decrease in plasma injection regions and a latitude-dependent wave normal angle distribution on the energization of electrons by whistler mode waves at Jupiter are investigated. Previous work…1 January, 2011 by Philip Trathan
How top avian predators are distributed at sea during the inter-breeding period remains poorly known. Here we focused on the pelagic seabird that is the single greatest avian consumer of…Read more on Inter-population segregation in the wintering areas of macaroni penguins
1 January, 2011 by Philip Trathan
For land-breeding marine organisms such as seabirds, knowledge about their habitat use has mainly been gained through studies of breeding individuals that are constrained to return frequently to their breeding…1 January, 2011 by Michael Thorne, Roger Worland, Melody Clark
The Arctic springtail, Megaphorura arctica Tullberg 1876 (Onychiuridae: Collembola), is one of the few organisms known to survive the extreme stresses of its environment by using cryoprotective dehydration. We have…1 January, 2011 by Philip Leat
The South Sandwich volcanic arc is sited on a young oceanic crust, erupts low-K tholeiitic rocks, is characterized by unexotic pelagic and volcanogenic sediments on the down-going slab, and simple…1 January, 2011 by Philip Trathan, Peter Fretwell
In 1948, a small colony of emperor penguins Aptenodytes forsteri was discovered breeding on Emperor Island (67 degrees 51' 52 '' S, 68 degrees 42' 20 '' W), in the…1 January, 2011 by Richard Phillips
Currently, 17 of 22 albatross species are listed as Vulnerable, Endangered, or Critically endangered by the International Union for the Conservation of Nature (IUCN). Incidental mortality in fisheries is by…Read more on An assessment of seabird-fishery interactions in the Atlantic Ocean
1 January, 2011 by Jonathan Shanklin
The Antarctic ozone holes of 2008 and 2009 are reviewed from various perspectives, making use of a range of Australian data and analyses. In both years, ozone holes formed that…1 January, 2011
In the face of stochastic climatic perturbations, the overall stability of an ecosystem will be determined by the balance between its resilience and its resistance, but their relative importance is…1 January, 2011 by David Vaughan, David Barnes, Peter Fretwell
The West Antarctic ice sheet (WAIS) has long been considered vulnerable to rapid retreat and today parts are rapidly losing ice. Projection of future change in WAIS is, however, hampered…1 January, 2011 by Dominic Hodgson, Gareth Marshall, Stephen Roberts
We review the post-glacial climate variability along the East Antarctic coastline using terrestrial and shallow marine geological records and compare these reconstructions with data from elsewhere. Nearly all East Antarctic…1 January, 2011 by Michael Thorne, Melody Clark
Background Fish scales are an important reservoir of calcium and phosphorus and together with the skin function as an integrated barrier against environmental changes and external aggressors. Histological studies have…Read more on Skin healing and scale regeneration in fed and unfed sea bream, Sparus auratus
1 January, 2011 by Alistair Crame
Laocoetis piserai n. sp. (Hexactinellida, Porifera) from the mid-Cretaceous (i.e., Albian–Cenomanian) of James Ross Island is the first record of a fossil sponge from Antarctica. This new occurrence of a…Read more on First fossil sponge from Antarctica and its palaeobiogeographical significance
1 January, 2011 by Philip Trathan, Richard Phillips
Telemetry methods and remote sensing now make it possible to record the spatial usage of wide-ranging marine animals and the biophysical characteristics of their pelagic habitats. Furthermore, recent statistical advances…1 January, 2011 by Dominic Hodgson, Peter Fretwell, Robert Larter, Stephen Roberts
Precise relative sea level (RSL) data are important for inferring regional ice sheet histories, as well as helping to validate numerical models of ice sheet evolution and glacial isostatic adjustment.…Read more on A new Holocene relative sea level curve for the South Shetland Islands, Antarctica
1 January, 2011
In this study we examined the hypothesis that, under conditions of replete macronutrients and iron in the Southern Ocean, phytoplankton abundance and specific N uptake rates are influenced strongly by…1 January, 2011 by Huw Griffiths, Katrin Linse, Rowan Whittle
Limopsis is one of the most speciose and widespread bivalve genera in the Southern Ocean at the present day. However, the fossil record of the genus is poorly known from…1 January, 2011
A discrete-element model of sea ice is used to study how a 900 change in wind direction alters the pattern of faults generated through mechanical failure of the ice. The…Read more on Modelling the reorientation of sea-ice faults as the wind changes direction
1 January, 2011 by Eric Wolff
Predicting how climate will change in the future requires a sound understanding of physical processes. This is underpinned by observation of how and why climate has changed in the past.…1 January, 2011 by Eric Wolff
The rising trend in atmospheric concentrations of methane over the past 5,000 years has been attributed to human agency. A modelling study, of a power that has only now become…1 January, 2011 by Eric Wolff
While the trends in greenhouse gas concentrations in recent decades are clear, their significance is only revealed when viewed in the context of a longer time period. Fortunately, the air…Read more on Greenhouse gases in the earth system: a palaeoclimate perspective
1 January, 2011 by Richard Phillips
Cephalopods are components of the diet of many predators worldwide. They are identified mainly using their chitinized upper and lower beaks, but because it has been assumed that the number…1 January, 2011 by Philip Trathan
As the spatial distribution of marine organisms is often affected by seasonal changes, pelagic seabirds may change their foraging areas in response to seasonal changes in the marine environment. Here,…1 January, 2011 by Eugene Murphy, Emma Young, Michael Meredith
The marine ecosystem on the shelf and open ocean adjacent to South Georgia is extraordinarily rich, with a history of commercial exploitation. Although much progress has been made, attempts at…1 January, 2011 by Melody Clark
Insects in the field are exposed to multiple bouts of cold, and there is increasing evidence that the fitness consequences of repeated cold exposure differ from the impacts of a…1 January, 2011 by Nigel Meredith, Richard Horne
Understanding the dynamics of the Earth's radiation belts is important for modeling and forecasting the intensities of energetic electrons in space. Wave diffusion processes are known to be responsible for…Read more on Effects of energy and pitch angle mixed diffusion on radiation belt electrons
22 December, 2010 by Adrian Jenkins, Keith Makinson, Pierre Dutrieux
Sub-ice shelf circulation and freezing/melting rates in ocean general circulation models depend critically on an accurate and consistent representation of cavity geometry. Existing global or pan-Antarctic data sets have turned…16 December, 2010 by Liz Thomas, Louise Sime, Robert Mulvaney, Thomas Bracegirdle
This study uses ice core methanesulphonic acid (MSA) records from the Antarctic Peninsula, where temperatures have been warming faster than anywhere else in the Southern Hemisphere, to reconstruct the 20th…14 December, 2010
We present statistical methods to determine climate regimes for the last glacial period using three temperature proxy records from Greenland: measurements of δ18O from the Greenland Ice Sheet Project 2…1 December, 2010 by Mark Clilverd
AARDDVARK data from a radio wave receiver in Sodankyla, Finland have been used to monitor transmissions across the auroral oval and just into the polar cap from the very low…1 December, 2010 by Mark Clilverd
We report a comparison of Solar Anomalous Magnetospheric Particle Explorer detected relativistic electron microbursts and short-lived subionospheric VLF perturbations termed FAST events, observed at Sodankyl Geophysical Observatory, Finland, during 2005.…1 December, 2010 by John King, Paul Holland
The winter advance of the sea ice edge in the Bellingshausen Sea is frequently interrupted by periods of rapid retreat lasting a few days. The frequency and duration of such…Read more on Analysis of a rapid sea ice retreat event in the Bellingshausen Sea
1 December, 2010 by Mark Clilverd
The full potential of whistlers for monitoring plasmaspheric electron density variations has not yet been realized. The primary reason is the vast human effort required for the analysis of whistler…1 December, 2010 by David Barnes, Huw Griffiths, Lloyd Peck, Simon Morley
Antarctic marine invertebrates from the Western Antarctic Peninsula (WAP) are generally stenothermal, with three-month survival and activity limits above the average maximum summer seawater temperature (1.0 degrees C) of 1-6…1 December, 2010 by Mark Clilverd
It has long been recognized that whistler-mode waves can be trapped in plasmaspheric whistler ducts which guide the waves. For nonguided cases these waves are said to be "nonducted", which…1 December, 2010
During winter the ocean surface in polar regions freezes over to form sea ice. In the summer the upper layers of sea ice and snow melts producing meltwater that accumulates…1 December, 2010 by Richard Horne
Strong electron cyclotron harmonic (ECH) waves have been observed by Cassini associated with local plasma injection regions in the Saturnian magnetosphere. Using measured electron distributions from the Cassini plasma spectrometer,…23 November, 2010 by Howard Roscoe
In June 2009, 22 spectrometers from 14 institutes measured tropospheric and stratospheric NO2 from the ground for more than 11 days during the Cabauw Intercomparison Campaign of Nitrogen Dioxide measuring…19 November, 2010 by Liz Thomas
Desert dust perturbs climate by directly and indirectly interacting with incoming solar and outgoing long wave radiation, thereby changing precipitation and temperature, in addition to modifying ocean and land biogeochemistry.…Read more on Observed 20th century desert dust variability: impact on climate and biogeochemistry
17 November, 2010 by Nigel Meredith
This study explores the manner in which the plasmapause is responsible for dictating which magnetospheric source regions of ELF/VLF chorus are able to propagate to and be received by midlatitude…Read more on Role of the plasmapause in dictating the ground accessibility of ELF/VLF chorus
11 November, 2010 by Richard Horne
Plasmaspheric plumes created during disturbed geomagnetic conditions have been suggested as a major cause of increased occurrences of electromagnetic ion cyclotron (EMIC) waves at these times. We have catalogued occurrences…1 November, 2010 by Anna Jones
A modelling study of radical chemistry in the coastal Antarctic boundary layer, based upon observations performed in the course of the CHABLIS (Chemistry of the Antarctic Boundary Layer and the…Read more on Coupling of HOx, NOx and halogen chemistry in the Antarctic boundary layer
1 November, 2010 by Richard Horne
Coupling between the Rice Convection Model and Ring Current-Atmospheric Interactions Model codes is used to simulate the dynamical evolution of ring current ion phase space density and the thermal electron…Read more on Global simulation of magnetosonic wave instability in the storm time magnetosphere
1 November, 2010 by Mark Clilverd
Geomagnetic storms triggered by coronal mass ejections and high-speed solar wind streams can lead to enhanced losses of energetic electrons from the radiation belts into the atmosphere, both during the…1 October, 2010 by John King, Thomas Lachlan-Cope
Polynyas play an important role in the regional meteorology and oceanography of the high latitudes and in the global ocean circulation. Unique low-level observations of an Antarctic coastal polynya, the…Read more on Convective heat transfer over thin ice covered coastal polynyas
1 October, 2010
A discrete element model is used to study shear rupture of sea ice under convergent wind stresses. The model includes compressive, tensile, and shear rupture of viscous elastic joints connecting…Read more on Effect of shear rupture on aggregate scale formation in sea ice
15 September, 2010 by Hilmar Gudmundsson
The advance of a glacier over a deforming sediment layer is analysed numerically. We treat this problem as a contact problem involving two slowly-deforming viscous bodies. The surface evolution of…Read more on A numerical study of glacier advance over deforming till
10 September, 2010 by Gareth Chisham, Mervyn Freeman
The open-closed magnetic field line boundary (OCB) delimits the region of open magnetic flux forming the polar cap in the Earth’s ionosphere. We present a reliable, automated method for determining…7 September, 2010 by Richard Phillips
* 1. The global decline of albatrosses (Diomedidae: Procellariiformes) is thought to have occurred largely as a direct result of fishery-related mortality. Albatrosses and other large petrels interact with fisheries…1 September, 2010 by David Vaughan, Liz Thomas, Robert Arthern, Robert Mulvaney
We describe in situ measurements of the compaction of Antarctic snow. At three different sites in Antarctica, the rate of compaction was measured hourly, over various depth intervals, for up…Read more on In situ measurements of Antarctic snow compaction compared with predictions of models
1 September, 2010 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
Multibeam swath bathymetry and sub-bottom profiler data are used to establish constraints on the flow and retreat history of a major palaeo-ice stream that carried the combined discharge from the…1 September, 2010 by Richard Horne
Chorus, a naturally occurring magnetospheric electromagnetic wave, is believed to be the result of a long chain of physical processes starting with supergranular circulation at the sun. The interaction of…Read more on Introduction to the special section on Chorus: Chorus and its role in space weather
24 August, 2010 by Anna Jones, Eric Wolff, Gareth Marshall, Howard Roscoe, Neil Brough, Steve Colwell
The majority of tropospheric ozone depletion event (ODE) studies have focussed on time-series measurements, with comparatively few studies of the vertical component. Those that exist have almost exclusively used free-flying…21 August, 2010 by Peter Kirsch, Richard Horne
The slot-region between Earth's inner and outer electron radiation belts was observed on 24 February 2004 by the satellite STSAT-1 to be populated by quasi-trapped electrons of energy 100-400 keV.…1 August, 2010 by Mark Clilverd, Paul Breen, Tracy Moffat-Griffin
Transmissions from three U.S. VLF (very low frequency) transmitters were received at Churchill, Canada, during an event study in May to November, 2007. This period spans four cycles of recurrent…Read more on Energetic outer radiation belt electron precipitation during recurrent solar activity
1 August, 2010 by Nigel Meredith
Wave-particle interactions can play a key role in the process of transfer of energy between different electron populations in the outer Van Allen radiation belt. We present a case study…Read more on Wave-particle interactions in the equatorial source region of whistler-mode emissions
1 August, 2010 by Claire Allen, Claus-Dieter Hillenbrand, James Smith
Cores from a contourite drift on the continental slope in the NW Weddell Sea, Antarctica, contain up to four sandy foraminifer-rich layers (WA1–4), with dispersed ice-rafted debris (IRD), interbedded with…16 July, 2010 by Howard Roscoe
The passive tracer method is used to estimate ozone loss from ground-based measurements in the Antarctic. A sensitivity study shows that the ozone depletion can be estimated within an accuracy…Read more on Estimation of Antarctic ozone loss from ground-based total column measurements
1 July, 2010
Geological constraints on ice-sheet deglaciation are essential for improving the modelling of ice masses and understanding their potential for future change. Here we present a detailed interpretation of depositional environments…1 July, 2010 by Adrian Jenkins, Pierre Dutrieux
Thinning ice in West Antarctica, resulting from acceleration in the flow of outlet glaciers, is at present contributing about 10% of the observed rise in global sea level. Pine Island…1 July, 2010 by Richard Horne
The global distribution and spectral properties of electromagnetic ion cyclotron (EMIC) waves in the He+ band are simulated for the 21 April 2001 storm using a combination of three different…1 July, 2010 by Richard Hindmarsh, Richard Hindmarsh
Increase in ice-shelf melting is generally presumed to have triggered recent coastal ice-sheet thinning. Using a full-Stokes finite element model which includes a proper description of the grounding line dynamics,…Read more on Coupling of ice-shelf melting and buttressing is a key process in ice-sheets dynamics
25 June, 2010
We study the dynamics of dimethylsulphide (DMS) and dimethylsulphoniopropionate (DMSP) using the global ocean biogeochemistry model PlankTOM5, which includes three phytoplankton and two zooplankton functional types (PFTs). We present a…Read more on Simulating dimethylsulphide seasonality with the Dynamic Green Ocean Model PlankTOM5
2 June, 2010 by Andy Smith, Ed King, Hugh Corr
Subglacial Lake Ellsworth has been proposed as a candidate for direct measurement and sampling, to identify microbial life and extract sedimentary climate records. We present a detailed characterization of the…1 June, 2010 by Gareth Chisham, Mervyn Freeman
We present, for the first time, the probability density function (PDF) of ionospheric vorticity measurements made by the SuperDARN HF radars. We show that the PDF is typically heavy-tailed and…Read more on On the non-Gaussian nature of ionospheric vorticity
1 June, 2010 by Teal Riley
The results of lithological mapping using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data for the Wright Peninsula region of Adelaide Island, Antarctic Peninsula are compared with existing geological…1 June, 2010 by Eric Wolff
It is generally accepted that variations in the precession and eccentricity of Earth's orbit, and Earth's axial tilt, influence long-term climate fluctuations; the combined variations are referred to as Milankovitch…1 May, 2010 by Andrew Clarke
1. We present a statistical analysis of the scaling of resting (basal) metabolic rate, BMR, with body mass, Bm and body temperature, Tb, in mammals. 2. Whilst the majority of…Read more on Scaling of basal metabolic rate with body mass and temperature in mammals
1 May, 2010 by Adrian Jenkins, Paul Holland
In the vicinity of the Antarctic Peninsula observations show diminishing sea ice and a rapid warming of atmosphere and ocean. These changes have led to the collapse of ice shelves…Read more on Ice and ocean processes in the Bellingshausen Sea, Antarctica
23 April, 2010 by Kevin Hughes
The Antarctic Treaty and associated agreements have little to say specifically on bioprospecting activities within the Treaty area. Consequently, Antarctic bioprospecting has elicited much debate within the Antarctic community, particularly…