Showing 11923 items
7 March, 2014 by Jane Francis
Evidence suggests that the early Eocene was a time of extreme global warmth. However, there are discrepancies between the results of many previous modelling studies and the proxy data at…Read more on Investigating vegetation-climate feedbacks during the early Eocene
3 March, 2014 by Geraint Tarling
The formation of two vertically discrete layers (bilayers) at night-time is a commonly observed phenomenon in zooplankton and is regularly found in Gullmarsfjord, a fjord with a 50 m sill…3 March, 2014 by Richard Phillips
We studied the year-round distribution and at-sea activity patterns of the sibling species, northern giant petrel Macronectes halli and southern giant petrel M. giganteus. Loggers combining light-based geolocators and immersion…1 March, 2014 by Kevin Hughes
Despite considerable research on biological invasions, key areas remain poorly explored, especially ways to reduce unintentional propagule transfer. The Antarctic represents a microcosm of the situation, with the numbers of…1 March, 2014 by Richard Phillips
Pelagic longline fisheries in the southwest Atlantic are a major conservation concern for several threatened seabirds, including four species of great albatrosses: wandering albatross (Diomedea exulans), Tristan albatross (Diomedea dabbenena),…1 March, 2014 by Paul Holland
Ice-shelf fractures frequently terminate where they encounter suture zones, regions of material heterogeneity that form between meteoric inflows in ice shelves. This heterogeneity can consist of marine ice, meteoric ice…Read more on The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica
1 March, 2014 by Richard Phillips
We hypothesized that changes in southeastern Bering Sea foraging conditions for black-legged kittiwakes (Rissa tridactyla) have caused shifts in habitat use with direct implications for population trends. To test this,…26 February, 2014 by Victoria Peck
Characterised by long term cooling and abrupt ice sheet expansion on Antarctica ~14 Ma ago, the mid Miocene marked the beginning of the modern ice-house world, yet there is still little…Read more on Deep ocean carbonate ion increase during mid Miocene CO2 decline
21 February, 2014 by James Smith, Joanne Johnson, Robert Larter
Pine Island Glacier, a major outlet of the West Antarctic Ice Sheet, has been undergoing rapid thinning and retreat for the past two decades. Here we demonstrate, using glacial-geological and…Read more on Rapid thinning of Pine Island Glacier in the early Holocene
15 February, 2014
Increased loads of land-based pollutants through river plumes are a major threat to the coastal water quality, ecosystems and sanitary heath. Identifying the coastal areas impacted by potentially polluted freshwaters…14 February, 2014 by Louise Sime
The evaluation of ice sheet models is one of the pressing problems in the study of ice sheets dynamics. Here we examine the question of how much isochronous information is…Read more on Isochronous information in a Greenland ice sheet radio-echo sounding dataset
12 February, 2014 by Markus Frey
Snow in the environment acts as a host to rich chemistry and provides a matrix for physical exchange of contaminants within the ecosystem. The goal of this review is to…12 February, 2014 by Iain Staniland, Jaume Forcada, Peter Fretwell
We describe a method of identifying and counting whales using very high resolution satellite imagery through the example of southern right whales breeding in part of the Golfo Nuevo, Península…Read more on Whales from space: counting southern right whales by satellite
12 February, 2014 by Fausto Ferraccioli, Hugh Corr, Tom Jordan
We present a detailed analysis of bed roughness beneath Institute and Möller Ice Streams, west Antarctica, using radio-echo sounding data (RES) acquired in the austral summer of 2010/11. We assess…11 February, 2014 by Vsevolod Afanasyev
Recent years have seen a growing consensus that events during one part of an animal's annual cycle can detrimentally affect its future fitness. Notably, migratory species have been shown to…10 February, 2014 by Andrew Wood, Jaume Forcada, Richard Phillips
Species in comparative demography studies often have a common phylogenetic or evolutionary ancestry and hence, they cannot fully be treated as independent samples in the statistical analysis. Although the serious…9 February, 2014 by Richard Phillips
Summary 1.Interspecific competitive interactions typically result in niche differentiation to alleviate competition through mechanisms including character displacement. However, competition is not the sole constraint on resource partitioning, and its effects…5 February, 2014 by Sandra McInnes, Sandra McInnes
Dividing the world into nine regions, this first paper describes literature records of the limno-terrestrial tardigrades (Tardigrada) reported from Central America. Updating previously published species lists we have revised the…Read more on Annotated zoogeography of non-marine Tardigrada. Part I: Central America
5 February, 2014 by Catharine Horswill, Hugh Venables, Iain Staniland, Norman Ratcliffe, Philip Trathan, Stacey Adlard
Competition for food among populations of closely related species and conspecifics that occur in both sympatry and parapatry can be reduced by interspecific and intraspecific spatial segregation. According to predictions…1 February, 2014 by Claus-Dieter Hillenbrand, Michael Meredith
The Antarctic Circumpolar Current is key to the mixing and ventilation of the world’s oceans. This current flows from west to east between about 45° and 70°S connecting the Atlantic,…1 February, 2014 by Hilmar Gudmundsson
Over the past 40 years Pine Island Glacier in West Antarctica has thinned at an accelerating rate, so that at present it is the largest single contributor to sea-level rise…Read more on Retreat of Pine Island Glacier controlled by marine ice-sheet instability
1 February, 2014 by Paul Holland
Sinking dense plumes are important in many oceanographic settings, notably the polar formation of deep and bottom waters. The dense water sources feeding such plumes are commonly affected by tidal…1 February, 2014 by Claus-Dieter Hillenbrand
Using a one-dimensional numerical model of ice-stream flow with robust grounding-line dynamics, we explore controls on paleo-ice-stream retreat in Marguerite Bay, Antarctica, during the last deglaciation. Landforms on the continental…1 February, 2014 by Adrian Jenkins, Paul Holland, Satoshi Kimura
Ocean freezing within ice-shelf basal crevasses could potentially act as a stabilizing influence on ice shelves; however, ice-ocean interaction and ocean dynamics within these crevasses are as yet poorly understood.…Read more on Modelling ice-ocean interaction in ice shelf crevasses
1 February, 2014 by Rosie Williams
The ability of unicellular green algal species such as Chlamydomonas reinhardtii to produce hydrogen gas via iron-hydrogenase is well known. However, the oxygen-sensitive hydrogenase is closely linked to the photosynthetic…30 January, 2014 by Nigel Meredith, Richard Horne
Whistler mode chorus is an important magnetospheric emission, playing a dual role in the acceleration and loss of relativistic electrons in the Earth's outer radiation belt. Chorus is typically generated…29 January, 2014 by Mark Clilverd
Using Microwave Limb Sounder (MLS/Aura) and Medium Energy Proton and Electron Detector (MEPED/POES) observations between 2005–2009, we study the longitudinal response of nighttime mesospheric OH to radiation belt electron precipitation.…27 January, 2014 by Richard Phillips
For more than 60 yr, electronic tags (including acoustic transmitters, archival loggers, and satellite tags) have been applied to free-ranging marine vertebrates to track their behaviour and characterize their spatial…23 January, 2014 by John King
A combination of observational data and modelling reveals the potential significance of the north and tropical Atlantic Ocean in driving change in Antarctic winds and sea ice on decadal timescales…Read more on Climate science: A resolution of the Antarctic paradox
23 January, 2014 by Deborah Pardo
Allocation decisions depend on an organism's condition which can change with age. Two opposite changes in life-history traits are predicted in the presence of senescence: either an increase in breeding…21 January, 2014 by Rachel Cavanagh
The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global…Read more on Extinction risk and conservation of the world’s sharks and rays
21 January, 2014 by Stephen Roberts
Lake sediments contain valuable information about past volcanic and seismic events that have affected the lake catchment, and they provide unique records of the recurrence interval and magnitude of such…16 January, 2014 by Michael Meredith
The fate of a deep boundary current that originates in the Southeast Pacific and flows southward along the continental slope of South America is elucidated. The current transports poorly ventilated…Read more on Deep boundary current disintegration in Drake Passage
15 January, 2014 by Richard Phillips
Animal populations are frequently limited by the availability of food or of habitat. In central-place foragers, the cost of accessing these resources is distance-dependent rather than uniform in space. However,…15 January, 2014 by Eugene Murphy, Emma Young, Sally Thorpe
The waters around South Georgia are among the most productive in the Southern Ocean, with zooplankton populations close to the island, in particular Antarctic krill, supporting vast colonies of higher…10 January, 2014 by Adrian Jenkins, Povl Abrahamsen, Jan De Rydt, Paul Holland, Pierre Dutrieux
Pine Island Glacier has thinned and accelerated over recent decades, significantly contributing to global sea-level rise. Increased oceanic melting of its ice shelf is thought to have triggered those changes.…Read more on Strong sensitivity of Pine Island ice-shelf melting to climactic variability
9 January, 2014 by Richard Phillips
Tracking technology has revolutionized knowledge of seabird movements; yet, few studies have examined sex differences in distribution and behavior of small to medium-sized, sexually-monomorphic seabirds. Application of bird-borne geolocation-immersion loggers…8 January, 2014 by Philip Trathan, Peter Fretwell
We describe a new breeding behaviour discovered in emperor penguins; utilizing satellite and aerial-survey observations four emperor penguin breeding colonies have been recorded as existing on ice-shelves. Emperors have previously…7 January, 2014 by Sebastian Rosier
Tides play an important role in ice sheet dynamics by modulating ice stream velocity, fracturing, and moving ice shelves and mixing water beneath them. Any changes in ice shelf extent…Read more on Modeling Antarctic tides in response to ice shelf thinning and retreat
3 January, 2014 by Fausto Ferraccioli, Hugh Corr, Tom Jordan
Repeat-pass ICESat altimetry has revealed 124 discrete surface height changes across the Antarctic Ice Sheet, interpreted to be caused by subglacial lake discharges (surface lowering) and inputs (surface uplift). Few…1 January, 2014 by Alex Brisbourne, Andy Smith, Ed King, Keith Makinson, Keith Nicholls, Paul Holland
Seismic reflection soundings of ice thickness and seabed depth were acquired on the Larsen C Ice Shelf in order to test a sub-shelf bathymetry model derived from the inversion of…Read more on Seabed topography beneath Larsen C Ice Shelf from seismic soundings
1 January, 2014 by Alexander Tate, Claus-Dieter Hillenbrand, Philip Leat, Robert Larter
New multibeam bathymetric data from the southeastern Weddell Sea show significant differences in surface morphology of the outer continental shelf and slope between two adjacent cross-shelf troughs. These are the…1 January, 2014 by Melody Clark
Increasing temperatures and glacier melting at the Western Antarctic Peninsula (WAP) are causing rapid changes in shallow coastal and shelf systems. Climate change-related rising water temperatures, enhanced ice scouring, as…1 January, 2014
Improvements in our ability to model runoff from glaciers remain an important scientific goal. This paper describes a new temperature-radiation-index glacier melt model specifically enhanced for use in High-Arctic environments,…1 January, 2014 by Lloyd Peck, Melody Clark, Simon Morley
Antarctic marine species have evolved in one of the coldest and most temperature-stable marine environments on Earth. They have long been classified as being stenothermal, or having a poor capacity…Read more on Acclimation and thermal tolerance in Antarctic marine ectotherms
1 January, 2014 by Philip Trathan
Technical progress in animal-borne tracking and movement data analysis has facilitated the understanding of the interplay between successive periods in the life cycle of migratory animals. We investigated how sex…1 January, 2014 by Elisabeth Biersma, Peter Convey
Arctic terrestrial ecosystems are generally considered to be species poor, fragile and often isolated. Nonetheless, their intricate complexity, especially that of the invertebrate component, is beginning to emerge. Attention has…1 January, 2014 by Nigel Meredith, Richard Horne, Sarah Glauert
The flux of relativistic electrons in the Earth's radiation belts is highly variable and can change by orders of magnitude on timescales of a few hours. Understanding the drivers for…1 January, 2014 by David Vaughan
Since the 1970s, the sudden, rapid collapse of 20% of ice shelves on the Antarctic Peninsula has led to large-scale thinning and acceleration of its tributary glaciers. The leading hypothesis…Read more on Firn air depletion as a precursor of Antarctic ice-shelf collapse
1 January, 2014 by Clara Manno
The timing of vertical migration in planktonic foraminifera (ex. ontogenetic, diel) is still an open debate. This work aims to investigate the diel vertical migration (DVM) of Neogloboquadrina pachyderma (N.…1 January, 2014 by Carlos Martin Garcia, Ed King, Hilmar Gudmundsson
Flow at ice divides, their shape, size and internal structure depend not only on local conditions, but also on the flow regimes and past histories of the surrounding ice masses.…1 January, 2014 by Fausto Ferraccioli, Hugh Corr, Tom Jordan
Antarctic subglacial highlands are where the Antarctic ice sheets first developed and the “pinning points” where retreat phases of the marine-based sectors of the ice sheet are impeded. Due to…1 January, 2014 by Louise Ireland
Antarctic krill (Euphausia superba) were sampled in contrasting habitats: a seasonally ice-covered deep ocean (Lazarev Sea), ice-free shelves at their northern range (South Georgia) and the Antarctic Peninsula (Bransfield Strait),…1 January, 2014 by Lloyd Peck
This paper presents the output of our fifth annual horizon-scanning exercise, which aims to identify topics that increasingly may affect conservation of biological diversity, but have yet to be widely…Read more on A horizon scan of global conservation issues for 2014
1 January, 2014 by Geraint Tarling, Peter Ward, Sally Thorpe
Mesozooplankton samples taken during the Discovery Investigations in the Southern Ocean in the 1930’s were analysed from a series of 5 transects along 80oW. The samples provide a unique level…1 January, 2014 by Lloyd Peck, Melody Clark, Simon Morley
Metabolic rate is a key component of energy budgets that scales with body size and varies with large-scale environmental geographical patterns. Here we conduct an analysis of standard metabolic rates…1 January, 2014 by Huw Griffiths, Alistair Crame, Katrin Linse, Rowan Whittle
The fossil community from the Early Miocene Cape Melville Formation (King George Island, Antarctica) does not show the archaic retrograde nature of modern Antarctic marine communities, despite evidence, such as…1 January, 2014
The Polar Regions play an important role in the global processes of our planet, from climate change to sea level rise, protection from UV (ultraviolet) radiation to uptake of carbon…Read more on Education and polar research: bringing polar science into the classroom
1 January, 2014 by Michael Dunn, Norman Ratcliffe, Philip Trathan, Stacey Adlard
We present a design for a simple, inexpensive leg band for mounting GLS tags on penguins. It causes a low level of injury and can be made from materials and…Read more on A leg-band for mounting geolocator tags on penguins
1 January, 2014 by Jonathan Shanklin
We review the 2012 Antarctic ozone hole, making use of various meteorological reanalyses, remotely sensed ozone measurements and ground-based measurements of ultra-violet radiation. Based on analysis of 33 years of…1 January, 2014 by Jonathan Shanklin
The Antarctic ozone hole of 2011 is reviewed from a variety of perspectives, making use of various data and analyses. The ozone hole of 2011 was relatively large in terms…1 January, 2014
Little is known of the endangered and declining western North Atlantic population of the Roseate Tern Sterna dougallii outside the breeding season, when most mortality probably occurs. We used geolocators…17 December, 2013 by Chester Sands
Phylogeographic studies provide a framework for understanding the importance of intrinsic versus extrinsic factors in shaping patterns of biodiversity through identifying past and present microevolutionary processes that contributed to lineage…17 December, 2013
During the heroic age of Antarctic exploration, general anaesthesia was given on at least 11 occasions. This paper describes some of the surgery procedures performed, including on the doctors themselvesRead more on Surgery and anaesthesia during the heroic age of Antarctic exploration (1895-1922)
16 December, 2013 by Eric Wolff
Earth system models are increasing in complexity and incorporating more processes than their predecessors, making them important tools for studying the global carbon cycle. However, their coupled behaviour has only…16 December, 2013 by Keith Nicholls
Over the last decade, several hundred seals have been equipped with conductivity-temperature-depth (CTD) sensors in the Southern Ocean for both biological and physical oceanographic studies. A calibrated collection of seal-derived…16 December, 2013 by Anna Jones
HCHO was monitored throughout the year 2009 at the coastal East Antarctic site of Dumont d'Urville (DDU) using Aerolaser AL-4021 analyzers. The accurate determination of less than 100 pptv required…9 December, 2013 by Jennifer Jackson, Katrin Linse
A new deep-sea stalked barnacle, Vulcanolepas scotiaensis sp. nov. is described from hydrothermal vents at depths of 2400–2600 metres along segments of the East Scotia Ridge and from 1400 metres…9 December, 2013 by Mark Clilverd
The energy spectra of energetic electron precipitation from the radiation belts are studied in order to improve our understanding of the influence of radiation belt processes. The Detection of Electromagnetic…7 December, 2013 by Simon Morley
Species with broader geographical ranges are expected to be ecological generalists, while species with higher heat tolerances may be relatively competitive at more extreme and increasing temperatures. Thus, both traits…Read more on Geographical range, heat tolerance and invasion success in aquatic species
6 December, 2013 by Pierre Mathiot
The mid-Holocene (6 kyr BP; thousand years before present) is a key period to study the consistency between model results and proxy-based reconstruction data as it corresponds to a standard…1 December, 2013 by Peter Convey
This paper presents the results of a biodiversity study of microfungi in ornithogenic soils from Beaufort Island (Ross Sea, continental Antarctic). During the 2004/05 austral summer, we sampled a wide…1 December, 2013 by Adrian Jenkins, Deb Shoosmith, Keith Nicholls
The presence of warm Circumpolar Deep Water (CDW) intrusions on the Amundsen continental shelf has been linked to recent thinning of the outlet glaciers draining the West Antarctic ice sheet…1 December, 2013 by Jane Francis, Vanessa Bowman
The Late Cretaceous is considered to have been a time of greenhouse climates, although evidence from Maastrichtian sediments for rapid and significant sea-level changes suggests that ice sheets were growing…1 December, 2013 by Huw Griffiths
The geographical coverage of a comprehensive dataset on Antarctic macrobenthic communities is provided for the first time. Since the sampling methods applied since the 1950s vary considerably, a robust analysis…Read more on Circumpolar overview and spatial heterogeneity of Antarctic macrobenthic communities
1 December, 2013 by Keith Nicholls
Marine ice is an important factor in ice shelf stability. An extensive marine ice layer is present under the Amery Ice Shelf (AIS), East Antarctica. This paper documents observations on…1 December, 2013 by Simeon Hill
The goals of ecosystem based management (EBM) are strategically ambiguous, meaning that they require interpretation to identify objectives for ecosystem state. Ecosystem states that are useful for achieving such objectives…1 December, 2013 by Adrian Jenkins, Paul Holland, Thomas Millgate
The presence of ice shelf basal channels has been noted in a number of Antarctic and Greenland ice shelves, but their impact on basal melting is not fully understood. Here…Read more on The effect of basal channels on oceanic ice-shelf melting
1 December, 2013 by David Newnham, David Maxfield, Mark Clilverd, Richard Horne
We report ground-based measurements of the polar middle atmosphere made using a 230-250 GHz passive microwave radiometer deployed at Troll station (72°01’S 02°32’E, L-shell of L = 4.8), Antarctica. Our observations show enhanced…1 December, 2013 by Deborah Pardo
Sex differences in lifespan and aging are widespread among animals. Since investment in current reproduction can have consequences on other life-history traits, the sex with the highest cost of breeding…Read more on Females better face senescence in the wandering albatross
1 December, 2013 by Povl Abrahamsen
This synthesis study assesses recent changes of Arctic Ocean physical parameters using a unique collection of observations from the 2000s and places them in the context of long-term climate trends…Read more on Recent oceanic changes in the Arctic in the context of long-term observations
1 December, 2013 by Andrew Kavanagh, Mark Clilverd
Energetic Electron Precipitation (EEP) impacts the chemistry of the middle atmosphere with growing evidence of coupling to surface temperatures at high latitudes. To better understand this link it is essential…1 December, 2013 by Dominic Hodgson
Bathurst Harbour in World Heritage southwest Tasmania, Australia, is one of the world’s most pristine estuarine systems. At present there is a lack of data on pollution impacts or long-term…1 December, 2013 by Dominic Hodgson, Stephen Roberts
To fully understand the Holocene climatic variability in the sub-polar latitudes of the Southern Hemisphere and its driving mechanisms, like the Southern Hemisphere westerly winds, we undertook a multi-proxy analysis…Read more on A paleolimnological reconstruction of Holocene climate change in southern Patagonia
1 December, 2013 by David Pearce, Peter Convey
The Antarctic represents a largely untapped source for isolation of new microorganisms with potential to produce bioactive natural products. Actinomycetes are of special interest among such microorganisms as they are…29 November, 2013 by Richard Hindmarsh, Richard Hindmarsh
Fast-flowing glaciers and ice streams are pathways for ice discharge from the interior of the Antarctic Ice Sheet to ice shelves, at rates controlled by conditions at the ice-bed interface.…26 November, 2013 by Martin Miller
Lin et al. (1) claim to have discovered a positive 17O anomaly in water vapor from Alert, Canada, indicative of a component of stratospheric origin. However, their data (Tables S1−S5)…Read more on Oxygen isotope anomaly not present in water vapor from Alert, Canada
20 November, 2013 by Richard Phillips
Croxall et al. (2013; Mar Ecol Prog Ser 493:297-300) assert that fine-scale analysis of seabird-fisheries overlap, such as that presented in Torres et al. (2013; Mar Ecol Prog Ser 473:275-289),…20 November, 2013 by Gareth Marshall, Scott Hosking, John Turner, Tony Phillips
On 24 September 2012 the Antarctic sea ice extent (SIE) reached a new annual daily maximum (ADM) for the satellite era of 19.72 × 106 km2. The largest positive SIE anomalies compared to…11 November, 2013 by Jonathan Kingslake
We use the Shreve hydraulic potential equation as a simplified approach to investigate potential subglacial lake locations and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets. We validate…8 November, 2013
For over the past 50 years the tag line for Antarctica has been "A continent for peace and science," leaving the rest of human activities rather adrift. Yes, there have…Read more on Review of Exploring Antarctic values, by Daniela Liggett & Alan D. Hemmings (2013)
5 November, 2013 by Mark Clilverd, Neil Cobbett
Data from two autonomous VLF radio receiver systems installed in a remote region of the Antarctic in 2012 is used to take advantage of the juxtaposition of the L = 4.6 contour,…5 November, 2013 by Eric Wolff, Michael Dinn, Robert Arthern, Richard Hindmarsh, Robert Mulvaney, Richard Hindmarsh
The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and…Read more on Where to find 1.5 million yr old ice for the IPICS “Oldest-Ice” ice core
1 November, 2013 by Eric Wolff
Sea ice plays an important role in Earth's climate system. The lack of direct indications of past sea ice coverage, however, means that there is limited knowledge of the sensitivity…Read more on A review of sea ice proxy information from polar ice cores
1 November, 2013 by Claire Allen, Dominic Hodgson
Antarctic sea-ice plays a primary role in the climate system, potentially modulating interhemispheric millennial-scale climate change and deglacial warming. Recently, microfossil proxy data have provided important insights into this potential…1 November, 2013 by Richard Phillips
Life-history theory predicts that costs are associated with reproduction. One possible mediator of costs involves the secretion of glucocorticoid hormones, which in birds can be measured in feathers grown during…Read more on Corticosterone mediated costs of reproduction link current to future breeding
1 November, 2013 by Eric Wolff
We argue that, while Milanković variations in solar radiation undoubtedly have a major influence on the timing of the Quaternary ice ages, they are partly incidental to their underlying causes.…1 November, 2013
Here we demonstrate the ability of stochastic reduced order models to predict the statistics of non-stationary systems undergoing critical transitions. First, we show that the reduced order models are able…Read more on Predictions of critical transitions with non-stationary reduced order models