Showing 11205 items
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;…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 Tom Jordan
The basins of southern McMurdo Sound have evolved under the influence of lithospheric flexure induced by the loads of the Erebus Volcanic Province. To characterise these basins, it is important…Read more on Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica
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…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
11 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
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 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…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
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
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
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
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…1 March, 2012 by Mark Clilverd
This paper shows that at solar maximum, equatorial ion densities at L = 2.5 are substantially higher at American longitudes in the December months than in the June months. This…Read more on The annual and longitudinal variations in plasmaspheric ion density
1 March, 2012
As part of a collaborative program between British Antarctic Survey and Utah State University, measurements were made using an all-sky airglow imager located at the U.K. Halley Station (76°S, 27°W)…27 February, 2012 by Emily Shuckburgh, Howard Roscoe
New evidence from models, ozone measurements and balloon trajectories is presented that confirms the existence of a broad cohesive region of air at the edge of the Antarctic stratospheric vortex…Read more on The existence of the edge region of the Antarctic stratospheric vortex
1 February, 2012 by Mark Clilverd, Neil Cobbett
Using ground-based subionospheric radio wave propagation data from two very low frequency (VLF) receiver sites, riometer absorption data, and THEMIS satellite observations, we examine in detail energetic electron precipitation (EEP)…1 January, 2012
The Southern Ocean is the world's largest high nutrient low chlorophyll (HNLC) region. However, satellite images highlight several areas associated with island chains and shallow topographic features which display high…Read more on Seasonal and spatial dynamics of iron availability in the Scotia Sea
1 January, 2012 by Anna Jones
The role of ice in the formation of chemically active halogens in the environment requires a full understanding because of its role in atmospheric chemistry, including controlling the regional atmospheric…1 January, 2012 by Peter Convey
Two species of chironomid midges are currently described in the genus Belgica Jacobs, 1900. Belgica antarctica Jacobs, 1900 is endemic to parts of the maritime Antarctic, and Belgica albipes (Séguy,…1 January, 2012 by Jennifer Jackson
Lineages undergoing rapid radiations provide exceptional opportunities for studying speciation and adaptation, but also represent a challenge for molecular systematics because retention of ancestral polymorphisms and the occurrence of hybridization…Read more on Species tree of a recent radiation: The subfamily Delphininae (Cetacea, Mammalia)
1 January, 2012 by Geraint Tarling, Simeon Hill
This paper aims to provide the overview needed to include krill in food-web models and to guide modellers to key sources of data. It describes the strengths of each method…1 January, 2012 by Paul Geissler, Sophie Fielding
The kinetics of food processing by zooplankton affects both their energy budgets and the biogeochemical fate of their fecal pellets. We sampled 40 schools of krill across the Scotia Sea…1 January, 2012 by Peter Ward
There is an enormous amount of data on Southern Ocean (SO) zooplankton, mostly on their distribution with a minority addressing rate processes. This review aims to summarise these data and…1 January, 2012
The consolidation and bond strength of rafted sea ice were investigated through a series of experiments undertaken in the Ice Physics Laboratory at the UCL. To simulate a section of…Read more on The consolidation and bond strength of rafted sea ice
1 January, 2012
The northern wheatear (Oenanthe oenanthe) is a small (approx. 25 g), insectivorous migrant with one of the largest ranges of any songbird in the world, breeding from the eastern Canadian…1 January, 2012 by Anna Jones, Eric Wolff, Howard Roscoe
NOx measurements were conducted at the Halley Research Station, coastal Antarctica, during the austral summer period 1 January–10 February 2005. A clear NOx diurnal cycle was observed with minimum concentrations…1 January, 2012
Winter ranges have been identified for most neotropical migrant bird species, those that spend the winter months in Central and South America and summer months in North America. Published accounts…Read more on The Northern Black Swift: Migration path and wintering area revealed
1 January, 2012 by Eugene Murphy, Geraint Tarling, Hugh Venables, Peter Ward, Sophie Fielding
The carbonate chemistry of the surface ocean is rapidly changing with ocean acidification, a result of human activities. In the upper layers of the Southern Ocean, aragonite—a metastable form of…Read more on Extensive dissolution of live pteropods in the Southern Ocean
1 January, 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…1 January, 2012 by Geraint Tarling, Sophie Fielding
Limacina helicina antarctica is a common part of the Southern Ocean zooplankton community but little is known about its life cycle. Here we determine the population structure and standing stock…1 January, 2012 by Geraint Tarling
Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns remain poorly described. The aim of this study was to collect and synthesise existing pteropod (Gymnosomata, Thecosomata…1 January, 2012 by Mark Belchier
This review summarises the available information on the biology and ecology of the lithodids at South Georgia and provides an overview of the development of a management regime for them.…1 January, 2012 by Andy Smith, David Vaughan, Ed King, Fausto Ferraccioli, Hamish Pritchard, Robert Larter
Current ice loss from the West Antarctic Ice Sheet (WAIS) accounts for about ten per cent of observed global sea-level rise1. Losses are dominated by dynamic thinning, in which forcings…Read more on Inland thinning of West Antarctic Ice Sheet steered along subglacial rifts
1 January, 2012 by Emma Boland, Emily Shuckburgh
Coherent jets are ubiquitous features of the ocean’s circulation, and their characteristics, such as orientation and energetics, may be influenced by topography. In this study, the authors introduce a large-scale,…Read more on The formation of nonzonal jets over sloped topography
1 January, 2012 by Thomas Bracegirdle
The current understanding of climate changes that have occurred in the last 50 years over Antarctica is presented with a focus on: (i) a summer warming of the eastern Antarctic…Read more on Detection and attribution of Antarctic climate change
1 January, 2012 by Gareth Marshall, Thomas Bracegirdle
In this study, surface and radiosonde data from staffed Antarctic observation stations are compared to output from five reanalyses [Climate Forecast System Reanalysis (CFSR), 40-yr ECMWF Re-Analysis (ERA-40), ECMWF Interim…1 January, 2012 by Eric Wolff
Abundant indirect evidence suggests that the West Antarctic Ice Sheet (WAIS) reduced in size during the Last Interglacial (LIG) compared to the Holocene. This study explores this possibility by comparing,…1 January, 2012
Field observations from the Trinity Peninsula Group at View Point on the Antarctic Peninsula indicate that thick, southward-younging and overturned clastic sedimentary rocks, comprising unusually coarse conglomeratic lenses within a…1 January, 2012 by Lloyd Peck
Global warming is a reality and its effects have been widely studied. However, the consequences for marine invertebrates remain poorly understood. Thus, the present study proposed to evaluate the effect…1 January, 2012 by Thomas Lachlan-Cope
Compared to other regions, little is known about clouds in Antarctica. This arises in part from the challenging deployment of instrumentation in this remote and harsh environment and from the…1 January, 2012 by Emilie Capron
The climate of the last glacial Marine Isotopic Stage 3 (MIS3) period is characterized by strong millennial-scale variability with a succession of Dansgaard–Oeschger events first identified in Greenland ice cores…Read more on Regional imprints of millennial variability during the MIS 3 period around Antarctica
1 January, 2012
We simulate the likely noisy situation near a reconnection region by superposing many 2D linear reconnection eigenmodes. The superposition of modes on the steady state X-type magnetic field creates multiple…Read more on Particle Acceleration in the Presence of Weak Turbulence at an X-Type Neutral Point
1 January, 2012 by Lloyd Peck, Melody Clark
The extensive regeneration ability of ophiuroids, particularly in relation to arm re-growth following amputation, is becoming increasingly recognized as a useful model system for understanding cellular differentiation and regeneration in…Read more on Intrinsic gene expression during regeneration in arm explants of Amphiura filiformis
1 January, 2012 by Peter Kirsch
The NERC Science Information Strategy Data Citation and Publication project aims to develop and formalise a method for formally citing and publishing the datasets stored in its environmental data centres.…1 January, 2012 by Jonathan Shanklin, Steve Colwell
The passage of a volcanic plume produced by the eruption of Eyjafjallajökull volcano in April 2010 was measured by the sunesky radiometers of the new European SkyRad (ESR) network. This…1 January, 2012 by Roger Worland, Peter Convey
The Antarctic Peninsula has experienced a strong climate warming trend of + 0.53 °C (mean annual air temperature) over the last 50 years. In the Polar Regions, changes in vegetation…1 January, 2012 by Deb Shoosmith, Claus-Dieter Hillenbrand, James Smith
The Antarctic Circumpolar Current is one of the key components of ocean circulation, and a knowledge of its isotopic composition is essential to the use of neodymium (Nd) isotopes to…1 January, 2012 by Richard Phillips
The wandering albatross (Diomedea exulans) is regarded as a generalist predator, but can it be consistent in its foraging niche at an individual level? This study tested short- and long-term…Read more on Short- and long-term consistency in the foraging niche of wandering albatrosses
1 January, 2012 by David Pearce, Peter Convey
Despite an increasing number of Antarctic soil diversity assessments, understanding of the bacterial community composition in the arid soil environments of the maritime/continental Antarctic transitional zone remains lacking. Most documented…1 January, 2012 by David Pearce, Peter Convey
We adopted a statistical approach to identify environmental parameters which might be important in structuring the bacterial community in soils on the Antarctic Peninsula. An assessment of soil bacterial community…1 January, 2012 by David Pearce, Peter Convey
Since the advent of 16SrRNAgene-based molecular analysis, an increasing amount of work has been conducted on the Antarctic soilbacterial community. The majority of such studies suggest that the Antarctic soil…1 January, 2012 by Kevin Hughes, Peter Convey, Susie Grant
The Antarctic Treaty System, acknowledged as a successful model of cooperative regulation of one of the globe’s largest commons ( 1), is under substantial pressure. Concerns have been raised about…Read more on Challenges to the future conservation of the Antarctic
1 January, 2012 by Kevin Hughes
Invasive alien species are among the primary causes of biodiversity change globally, with the risks thereof broadly understood for most regions of the world. They are similarly thought to be…1 January, 2012
We studied the seasonal lipid dynamics of Calanus finmarchicus from Loch Etive, a semi-enclosed fjordic environment on the west coast of Scotland, in relation to the diapause behavior of this…1 January, 2012 by Michael Thorne, Melody Clark
Several organisms display dormancy and developmental arrest at embryonic stages. Long-term survival in the dormant form is usually associated with desiccation, orthodox plant seeds and Artemia cysts being well documented…Read more on Long-Term Survival of Hydrated Resting Eggs from Brachionus plicatilis
1 January, 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 January, 2012 by Andrew Clarke
The mountainous island of South Georgia, situated in the cold but productive waters of the Southern Ocean, is one of the world’s most important seabird islands. It is estimated that…1 January, 2012 by Mark Clilverd
On 5 April 2010 a series of energetic electron injections, acceleration, and loss events appeared to induce an operational anomaly in the Galaxy 15 geosynchronous communications satellite. We describe the…1 January, 2012 by Claire Allen, Dominic Hodgson
Establishing accurate chronologies for Late Quaternary Antarctic marine sediments is often a challenge due to variable radiocarbon reservoir effects, the presence of coarse-grained glacial material and a lack of carbonate…1 January, 2012 by Claire Allen, Dominic Hodgson
Recent modeling suggests that changes in Southern Ocean sea-ice extent potentially regulated the exchange of CO2 release between the ocean and atmosphere during glacials. Unfortunately, a lack of high-resolution sea-ice…1 January, 2012 by Gabriele Stowasser, Hugh Venables, Martin Collins, Peter Enderlein, Sophie Fielding
Mesopelagic fish are a key component of the pelagic ecosystem throughout the world’s oceans. Opening and closing nets were used to investigate patterns in the distribution and abundance of mesopelagic…1 January, 2012 by Jennifer Jackson
Estimating the abundance of long-lived, migratory animals is challenging but essential for managing populations. We provide the first abundance estimates of endangered humpback whales Megaptera novaeangliae from their breeding grounds…