Showing 11923 items
1 February, 2013 by Victoria Peck
The delivery of ice-rafted debris (IRD) from glaciated margins is a function of ice sheet dynamics. Shifts in supply and sourcing of IRD can therefore identify episodes of ice sheet…1 February, 2013 by Roger Worland, Melody Clark
The Arctic springtail, Megaphorura arctica, survives sub-zero temperatures in a dehydrated state via trehalose-dependent cryoprotective dehydration. Regulation of trehalose biosynthesis is complex; based in part on studies in yeast and…1 February, 2013 by Kevin Hughes, Michael Thorne, Roger Worland, Peter Convey
Antarctica is the continent least affected by invasive species, but climate change and increasing human activity are increasing this threat. Antarctic terrestrial ecosystems generally have low biodiversity with simple community…1 February, 2013 by Norman Ratcliffe, Philip Trathan
Krill consumption by natural predators represents a critical link between surveys and models of standing krill biomass and the design of a sustainable krill fishery for the Scotia Sea. Antarctic…1 February, 2013 by Helen Peat, Peter Convey
A small, inconspicuous lichen, Acarospora cf. badiofusca, was discovered colonizing ironstained quartz mica schists on the lower slope of Manhaul Rock, a recently exposed nunatak on the McLeod Glacier, Signy…Read more on Iron localization in Acarospora colonizing schist on Signy Island
1 February, 2013 by Chester Sands, David Barnes, Huw Griffiths, Katrin Linse
Ophiuroids are a conspicuous and often dominant component of the Antarctic continental shelf benthos. Here we report on the ophiuroids collected from the Burdwood Bank, off the Patagonian Shelf, through…Read more on Observations of the ophiuroids from the West Antarctic sector of the Southern Ocean
1 February, 2013
Despite the general view that the Antarctic intertidal conditions are too extreme to support obvious signs of macrofaunal life, recent studies have shown that intertidal communities can survive over annual…Read more on Zonation in a cryptic Antarctic intertidal macrofaunal community
30 January, 2013 by Andrew Meijers, Emily Shuckburgh, Jean-Baptiste Sallee, Thomas Bracegirdle, Tony Phillips
An assessment of the fifth Coupled Models Intercomparison Project (CMIP5) models' simulation of the near-surface westerly wind jet position and strength over the Atlantic, Indian and Pacific sectors of the…28 January, 2013
I review the hierarchy of approaches to complex systems, focusing particularly on stochastic equations. I discuss how the main models advocated by the late Benoit Mandelbrot fit into this classification,…24 January, 2013 by Emilie Capron, Eric Wolff, Robert Mulvaney
Efforts to extract a Greenland ice core with a complete record of the Eemian interglacial (130,000 to 115,000 years ago) have until now been unsuccessful. The response of the Greenland…Read more on Eemian interglacial reconstructed from a Greenland folded ice core
24 January, 2013 by Jaume Forcada, Michael Thorne, Philip Trathan
Background Transcriptomes are powerful resources, providing a window on the expressed portion of the genome that can be generated rapidly and at low cost for virtually any organism. However, because…21 January, 2013 by Kevin Hughes
Antarctic Specially Protected Areas (ASPAs) represent the highest level of area protection within the Antarctic Treaty area. To reduce environmental impacts, ASPA visitors must comply with the Area's management plan…21 January, 2013 by Richard Phillips
Seabird-fishery interactions are currently a major issue in marine conservation management. A common approach to quantifying the extent of interactions is to overlay density maps of seabird and fishing activities…Read more on Scaling down the analysis of seabird-fishery interactions
16 January, 2013 by Alistair Crame
The widespread assumption that the origin of polar marine faunas is linked to the onset of major global cooling in the Late Eocene – Early Oligocene is being increasingly challenged.…Read more on Early Cenozoic differentiation of polar marine faunas
11 January, 2013 by Geraint Tarling
Marine planktonic organisms that undertake active vertical migrations over their life cycle are important contributors to downward particle flux in the oceans. Acantharia, globally distributed heterotrophic protists that are unique…9 January, 2013 by Richard Phillips
Limited knowledge of year-round seabird distributions hinders efforts to assess consequences of anthropogenic threats and climate-induced changes in the marine environment. In particular, there is urgent need to understand how…6 January, 2013 by Richard Phillips
The use of miniature data loggers is rapidly increasing our understanding of the movements and habitat preferences of pelagic seabirds. However, objectively interpreting behavioural information from the large volumes of…1 January, 2013 by Eugene Murphy, Lloyd Peck, Thomas Bracegirdle
Stresses on Antarctic ecosystems result from environmental change, including extreme events, and from (other) human impacts. Consequently, Antarctic habitats are changing, some at a rapid pace while others are relatively…1 January, 2013 by Peter Convey
Environmental manipulation studies are integral to determining biological consequences of climate warming. Open Top Chambers (OTCs) have been widely used to assess summer warming effects on terrestrial biota, with their…1 January, 2013 by Thomas Bracegirdle
Statistical relationships between future and historical model runs in multimodel ensembles (MMEs) are increasingly exploited to make more constrained projections of climate change. However, such emergent constraints may be spurious…1 January, 2013 by Eric Wolff
This study evaluates the influence of plausible changes in East Antarctic Ice sheet (EAIS) thickness and the subsequent glacio-isostatic response as a contributor to the Antarctic warming indicated by ice…1 January, 2013 by Mark Clilverd
[1] Using six Polar Orbiting Environmental Satellites (POES) satellites that have carried the Space Environment Module-2 instrument package, a total of 436,422 individual half-orbits between 1998 and 2010 were inspected…1 January, 2013 by Richard Horne
The French government has committed to launch the satellite TARANIS to study transient coupling processes between the Earth’s atmosphere and near-Earth space. The prime objective of TARANIS is to detect…Read more on Energetic charged particles above thunderclouds
1 January, 2013 by David Vaughan, Claus-Dieter Hillenbrand, James Smith, Robert Larter
Ice loss from the marine-based, potentially unstable West Antarctic Ice Sheet (WAIS) contributes to current sea-level rise and may raise sea level by ≤3.3 m or even ≤5 m in…Read more on Grounding-line retreat of the West Antarctic Ice Sheet from inner Pine Island Bay
1 January, 2013 by Chester Sands
A new brittle star attributable to the genus Ophiacantha is described from Antarctic waters, in the diffuse limits of the Antarctic Polar Front at Shag Rocks, South Georgia. The new…1 January, 2013 by Eugene Murphy, Emma Young, Geraint Tarling, Jonathan Watkins, Nadine Johnston, Philip Trathan, Peter Fretwell, Rachel Cavanagh, Sally Thorpe, Simeon Hill
The ocean ecosystems around the west Antarctic Peninsula and South Georgia are two of the best described regional ecosystems of the Southern Ocean. They therefore provide a useful basis for…1 January, 2013 by Andrew Orr, Howard Roscoe, Scott Hosking, Thomas Bracegirdle
A model simulation forced by prescribed ozone depletion shows strong dynamical modulation of the springtime cooling of the polar stratosphere associated with the Antarctic ozone hole. The authors find that…1 January, 2013 by Katrin Linse
The Antarctic marine environment is extreme in its low temperatures and short periods of primary productivity. Invertebrates must therefore adapt to maximise reproductive output where low temperature and limited food…1 January, 2013 by Richard Phillips
Many marine species are threatened by high levels of incidental mortality in fisheries. This paper reviews the design of selected recent, detailed Ecological Risk Assessments (ERAs) of the effects of…1 January, 2013 by Lloyd Peck
This paper presents the findings of our fourth annual horizon-scanning exercise, which aims to identify topics that increasingly may affect conservation of biological diversity. The 15 issues were identified via…Read more on A horizon scan of global conservation issues for 2013
1 January, 2013 by Claire Tancell, Geraint Tarling, Richard Phillips
There is an urgent need to identify key marine areas for conservation, particularly in the high seas. A range of techniques have been applied to tracking data from higher predators,…Read more on Comparison of methods for determining key marine areas from tracking data
1 January, 2013
Cephalopods are important prey for numerous seabird species. However, the physical mechanisms by which cephalopods (particularly species considered as deep-dwelling) become available to seabirds are poorly understood, and it has…1 January, 2013 by Simeon Hill
CCAMLR aims to develop a feedback approach to aid ecosystem-based management (EBM) of Antarctic krill fisheries. It is important to assess whether a feedback approach is likely to achieve the…1 January, 2013 by Simeon Hill
There is a global need to develop strategic frameworks for assessing uncertainty in ecosystem dynamics models. Such models have been used within CCAMLR to evaluate options for managing the Antarctic…1 January, 2013
The western sector of Ria Formosa, a lagoon system in the south of Portugal, represents approximately 90% of the total tidal prism of the lagoon and includes three inlets. Two…1 January, 2013 by Philip Trathan, Susie Grant
Recent rapid climate change is now well documented in the Antarctic, particularly in the Antarctic Peninsula region. One of the most evident signs of climate change has been ice-shelf collapse;…21 December, 2012 by David Vaughan
Over the last two decades, the Greenland ice sheet (GrIS) has been losing mass at an increasing rate, enhancing its contribution to sea-level rise (SLR). The recent increases in ice…20 December, 2012 by Richard Horne
In the current study we perform a comparative analysis of the gyroresonant interactions of whistler mode waves with radiation belt electrons in the magnetospheres of Earth, Jupiter, and Saturn. Our…19 December, 2012 by Thomas Bracegirdle
This study presents projections of twenty-first century wintertime surface temperature changes over the high-latitude regions based on the third Coupled Model Inter-comparison Project (CMIP3) multi-model ensemble. The state-dependence of the…19 December, 2012 by David Newnham
Using a ground-based microwave radiometer at Troll Station, Antarctica (72°S, 2.5°E, L = 4.76), we have observed a decrease of 20–70% in the mesospheric ozone, coincident with increased nitric oxide,…19 December, 2012 by David Vaughan, Hamish Pritchard
We combined an ensemble of satellite altimetry, interferometry, and gravimetry data sets using common geographical regions, time intervals, and models of surface mass balance and glacial isostatic adjustment to estimate…Read more on A reconciled estimate of ice sheet mass balance
18 December, 2012 by Claus-Dieter Hillenbrand
Marine-based ice streams whose beds deepen inland are thought to be inherently unstable. This instability is of particular concern because significant portions of the marinebased West Antarctic and Greenland ice…18 December, 2012
Glaciers and ice sheets are melting in response to climate warming. Whereas the physical behaviour of glaciers has been studied intensively, the biological processes associated with glaciers and ice sheets…Read more on Biological processes on glacier and ice sheet surfaces
18 December, 2012 by Gareth Marshall
Recent changes in the summer climate of the Southern Hemisphere extra-tropics are primarily related to the dominance of the positive phase of the Southern Annular Mode. This shift in the…17 December, 2012 by Philip Trathan
Food web knowledge is a prerequisite for adequate resource management in the Antarctic ecosystem. Accurate dietary specifications for the major consumers within the Antarctic ecosystem are needed. Procellariid species are…17 December, 2012 by Andrew Clarke
The metabolic theory of ecology (MTE) predicts the effects of body size and temperature on metabolism through considerations of vascular distribution networks and biochemical kinetics. MTE has also been extended…17 December, 2012 by Emily Shuckburgh
The ocean plays an essential role in determining aspects of the climate through its influence on coupled processes involving the atmosphere, cyrosphere and biogeochemistry, including budgets of heat and carbon…15 December, 2012 by Gareth Marshall
Observations of extratropical Southern Hemisphere austral summer precipitation over recent decades show mid-latitude drying and high-latitude moistening. Here we show that the observed precipitation trends in two datasets are inconsistent…Read more on Human influence on extratropical Southern Hemisphere precipitation
13 December, 2012 by Andrew Wood
To examine the general population trends of large whales in South Georgia waters, 2 opportunistic data sets of sightings of large whales from 1991 to 2010 around South Georgia were…12 December, 2012 by Hilmar Gudmundsson
The stability of marine ice sheets grounded on beds that slope upwards in the overall direction of flow is investigated numerically in two horizontal dimensions. We give examples of stable…Read more on The stability of grounding lines on retrograde slopes
1 December, 2012 by Deb Shoosmith, Claus-Dieter Hillenbrand, Robert Larter
Submarine gullies are the most common morphological features observed on Antarctic continental slopes. The processes forming these gullies, however, remain poorly constrained. In some areas, gully heads incise the continental…1 December, 2012 by Andrew Meijers, Emily Shuckburgh, Jean-Baptiste Sallee, Thomas Bracegirdle
The representation of the Antarctic Circumpolar Current (ACC) in the fifth Coupled Models Intercomparison Project (CMIP5) is generally improved over CMIP3. The range of modeled transports in the historical (1976–2006)…1 December, 2012 by Emma Woodfield, Richard Horne
In this paper we compare and contrast chorus, electron cyclotron harmonics (ECH), and Z mode emissions observed at Jupiter and Saturn and relate them to recent work on electron acceleration…27 November, 2012 by Howard Roscoe
Iodine compounds were measured above, below and within the sea ice of the Weddell Sea during a cruise in 2009, to make progress in elucidating the mechanism of local enhancement…Read more on Iodine emissions from the sea ice of the Weddell Sea
22 November, 2012 by Eric Wolff, Liz Thomas
We present an automated process for determining the annual layer chronology of an ice-core with a strong annual signal, utilising the hydrogen peroxide record from an Antarctic Peninsula ice-core as…Read more on Automated ice-core layer-counting with strong univariate signals
18 October, 2012 by David Vaughan
A high resolution surface topography Digital Elevation Model (DEM) is required to underpin studies of the complex glacier system on the Antarctic Peninsula. A complete DEM with better than 200m…16 October, 2012 by Emily Venables, Keith Makinson, Keith Nicholls
Hot-water drilled access holes were used to obtain oceanographic data from beneath two sites on Larsen C Ice Shelf, one in the north and one in the south. At both…Read more on Ocean circulation beneath Larsen C Ice Shelf, Antarctica from in situ observations
1 October, 2012 by Andrew Orr, Scott Hosking, Thomas Bracegirdle, Tony Phillips
The authors report a hypothesis for the dynamical mechanisms responsible for the strengthening of the Southern Hemisphere circumpolar winds from the lower stratosphere to the surface due to the ozone…1 October, 2012 by Nigel Meredith, Richard Horne
Gyroresonant wave particle interactions with whistler mode chorus play a fundamental role in the dynamics of the Earth’s radiation belts and inner magnetosphere, affecting both the acceleration and loss of…Read more on Global model of lower band and upper band chorus from multiple satellite observations
1 October, 2012 by Mark Clilverd
Observed phases and amplitudes of VLF radio signals propagating on (near) tropical all-sea paths, both short, ∼300 km, and long, ∼10 Mm, are used to find daytime parameter changes for…Read more on Tropical daytime lower D-region dependence on sunspot number
24 September, 2012 by Eric Wolff
Differences in the duration of interglacials have long been apparent in palaeoclimate records of the Late and Middle Pleistocene. However, a systematic evaluation of such differences has been hampered by…Read more on Can we predict the duration of an interglacial?
15 September, 2012
Although metaphorical and conceptual connections between the human brain and the financial markets have often been drawn, rigorous physical or mathematical underpinnings of this analogy remain largely unexplored. Here, we…Read more on Topological isomorphisms of human brain and financial market networks
1 September, 2012 by Catharine Horswill, Jennifer Jackson
Here we present the first documentation of humpback whales (Megaptera novaeangliae) in the Pitcairn Island region. Land-based surveys were conducted from Pitcairn Island from June 2007 to August 2007 in…Read more on Humpback whales wintering at Pitcairn Island, South Pacific
1 September, 2012 by Jaume Forcada, Melody Clark
Although single nucleotide polymorphisms (SNPs) are increasingly being recognized as powerful molecular markers, their application to non-model organisms can bring significant challenges. Among these are imperfect conversion rates of assays…1 September, 2012 by Dominic Hodgson, Peter Convey
Signy Island, maritime Antarctic, lies within the region of the Southern Hemisphere that is currently experiencing the most rapid rates of environmental change. In this study, peat cores up to…1 September, 2012 by Adrian Jenkins, David Vaughan, Hilmar Gudmundsson, Hugh Corr, Pierre Dutrieux
A dense grid of ice-penetrating radar sections acquired over Pine Island Glacier, West Antarctica has revealed a network of sinuous subglacial channels, typically 500 m to 3 km wide, and…1 September, 2012 by Keith Makinson, Keith Nicholls
To capture the austral summer to winter transition in water mass properties over the southern Weddell Sea continental shelf and slope region, 19 Weddell seals were tagged with miniaturized conductivity–temperature–depth…25 August, 2012 by Andrew Clarke, Terri Souster, Hugh Venables, Michael Meredith, Terri Souster
Climate change and human activities are expected to have a major impact on the structure and functioning of marine ecosystems and the biogeochemical cycles they mediate in the coming years.…9 August, 2012 by Eric Wolff
The most powerful explosions on the Sun – in the form of bright flares, intense storms of solar energetic particles (SEPs), and fast coronal mass ejections (CMEs) – drive the…4 August, 2012 by Emilie Capron
The orbital-scale transition from the last interglacial to glacial climate corresponds to the progressive organization of global millennial-scale climate variability. Here, we investigate the structure and the global fingerprint of…1 August, 2012 by Andrew Meijers
Knowledge of habitat use by top marine predators in response to environmental conditions is crucial in the current context of global changes occurring in the Southern Ocean. We examined the…1 August, 2012 by Rosie Williams
Despite a central role in immunity, antibody neutralization of virus infection is poorly understood. Here we show how the neutralization and persistence of adenovirus type 5, a prevalent nonenveloped human…Read more on Regulation of Virus Neutralization and the Persistent Fraction by TRIM21
1 August, 2012 by Mervyn Freeman
During geomagnetically disturbed conditions the midlatitude ionosphere is subject to intense poleward directed electric fields in the dusk-midnight sector. These electric fields lead to the generation of a latitudinally narrow…Read more on An examination of inter-hemispheric conjugacy in a subauroral polarization stream
19 July, 2012 by Terri Souster, Melody Clark, Terri Souster
Regeneration of arms in brittle stars is thought to proceed slowly in low temperature environments. Here a survey of natural arm damage and arm regeneration rates is documented in the…1 July, 2012 by Geraint Tarling, Sophie Fielding
Anthropogenic ocean acidification is likely to have negative effects on marine calcifying organisms, such as shelled pteropods, by promoting dissolution of aragonite shells. Study of shell dissolution requires an accurate…29 June, 2012 by Pierre Dutrieux
Analysis of results from an eddy-resolving general circulation model showed two subsurface velocity cores in the mean within the depth range between 400 and 1000 m below the Mindanao Current…Read more on Mindanao current/undercurrent in an eddy-resolving GCM
28 June, 2012 by Eric Wolff
The ice core record reveals large variations in the concentration of atmospheric methane, [CH4], over the last 800 kyr. Amongst the most striking natural features are the large, rapid rises…28 June, 2012 by Andy Smith, Tom Jordan
We present measurements of ice thickness, gravimetry and surface elevation on Pine Island Glacier, West Antarctica, separated by a period of 49 years. At one station, on the main trunk…Read more on Rapid subglacial erosion beneath Pine Island Glacier, West Antarctica
8 June, 2012 by Eric Wolff
This study aims at refining the synchronisation between the EPICA Dome C (EDC) and Vostok ice cores in the time interval 0–145 kyr BP by using the volcanic signatures. 102…1 June, 2012 by Jean-Baptiste Sallee
The Southern Ocean’s Antarctic Circumpolar Current (ACC) naturally lends itself to interpretations using a zonally averaged framework. Yet, navigation around steep and complicated bathymetric obstacles suggests that local dynamics may…30 May, 2012 by Hilmar Gudmundsson, Richard Hindmarsh, Richard Hindmarsh
Predictions of marine ice-sheet behaviour require models that are able to robustly simulate grounding line migration. We present results of an intercomparison exercise for marine ice-sheet models. Verification is effected…Read more on Results of the Marine Ice Sheet Model Intercomparison Project, MISMIP
16 May, 2012 by Mark Clilverd
Energetic particle precipitation leads to enhancement of odd hydrogen (HOx) below 80 km altitude through water cluster ion chemistry. Using measurements from the Microwave Limb Sounder (MLS/Aura) and Medium Energy…16 May, 2012 by Hua Lu, Ingrid Cnossen
This study analyzes geopotential height data from the ERA-40 and ERA-Interim reanalyses for the period of 1958–2009 to provide some new insights on the stratospheric Quasi-Biennial Oscillation (QBO) modulation of…Read more on QBO modulation of traveling planetary waves during northern winter
8 May, 2012 by Richard Phillips
Seabirds are facing a growing number of threats in both terrestrial and marine habitats, and many populations have experienced dramatic changes over past decades. Years of seabird research have improved…1 May, 2012 by Richard Horne
Wave propagation plays an important role in linking the chorus source in the plasma trough region and the hiss emission in the plasmasphere. We investigate the dependence of plasmaspheric hiss…1 May, 2012 by Richard Horne
There is increasing evidence that plasmaspheric hiss is formed by the evolution of a portion of chorus waves that are excited in the plasmatrough and propagate into the plasmasphere. Comparison…Read more on Modeling the properties of plasmaspheric hiss: 1. Dependence on chorus wave emission
1 May, 2012 by David Maxfield, Michael Rose
On 5 April 2010 a coronal mass ejection produced a travelling solar wind shock front that impacted the Earth's magnetosphere, producing the largest geomagnetic storm of 2010. The storm resulted…Read more on Ionospheric scintillation over Antarctica during the storm of 5-6 April 2010
1 May, 2012
On 20 January 2005, a solar energetic particle (SEP) event caused the largest recorded solar proton ground level event since 1956. Serendipitously, a balloon-borne experiment intended to measure effects of…1 May, 2012 by Hua Lu, Mark Clilverd
Advanced statistical methods are employed to analyze three long-term time series of geomagnetic activity indices (aa, IHV, and IDV) together with sunspot number (Rz) to examine whether or not the…Read more on Trend and abrupt changes in long-term geomagnetic indices
11 April, 2012 by Lloyd Peck, Michael Thorne, Simon Morley
Defining ecologically relevant upper temperature limits of species is important in the context of environmental change. The approach used in the present paper estimates the relationship between rates of temperature…11 April, 2012 by Alexandra Weiss, John King, Thomas Lachlan-Cope
This study investigates the surface albedo of the sea ice areas adjacent to the Antarctic Peninsula during the austral summer. Aircraft measurements of the surface albedo, which were conducted in…Read more on Albedo of the ice covered Weddell and Bellingshausen Seas
30 March, 2012 by Hilmar Gudmundsson
Longitudinal surface structures (“flowstripes”) are common on many glaciers but their origin and significance are poorly understood. In this paper we present observations of the development of these longitudinal structures…Read more on Longitudinal surface structures (flowstripes) on Antarctic glaciers
27 March, 2012 by Andrew Clarke
A high resolution time-series analysis of stable carbon isotopic signatures in particulate organic carbon (δ13CPOC) and associated biogeochemical parameters in sea ice and surface waters provides an insight into the…27 March, 2012 by John King
Data collected by two automatic weather stations (AWS) on the Larsen C ice shelf, Antarctica, between 22 January 2009 and 1 February 2011 are analyzed and used as input for…