Found 14089 items
1 September, 2015 by Kevin Newsham
l-isomeric amino acids and oligopeptides are thought to represent a key nitrogen (N) source for plants and soil microorganisms, bypassing the need to take up inorganic N, whilst self-cycling of…1 September, 2015 by Teal Riley
Calculating reliable temperatures of Mg-rich magmas is problematic because melt composition and KD(Fe-Mg)ol-liq, the key parameters of many traditional thermometers, are difficult to constrain precisely. The recently developed Al-in-olivine thermometer…1 September, 2015
When conducting marine seismic surveys it is important to know the vertical profile of the seismic streamer. Typically the streamer has a density that is different from the seawater; therefore…Read more on The vertical shape of a buoyant acoustic streamer between depth control units
1 September, 2015 by Xin Yang
Mercury (Hg) is a global pollutant that is known to have adverse effects on human health, and most human exposure to toxic methylmercury is through fish consumption. Soluble Hg compounds…1 September, 2015 by Michael Thorne, Melody Clark
The Brazilian oyster Crassostrea brasiliana was challenged to three common environmental contaminants: phenanthrene, diesel fuel water-accommodated fraction (WAF) and domestic sewage. Total RNA was extracted from the gill and digestive…1 September, 2015 by Richard Phillips
Aim Our current understanding of migratory strategies and the reasons for their high variability along the phylogenetic tree remains relatively poor. Most of the hypotheses relating to migration have been…1 September, 2015 by Jean-Baptiste Sallee
Understanding the responses of animals to the environment is crucial for identifying critical foraging habitat. Elephant seals (Mirounga leonina) from the Kerguelen Islands (49° 20’ S, 70° 20’ E) have…1 September, 2015 by Michael Dunn
Long-term monitoring of seabird numbers around Antarctica has revealed that the chinstrap penguin (Pygoscelis antarctica) is largely declining throughout its range in the Scotia Arc. Whether archipelagos across this large…1 September, 2015 by Peter Convey
Plants inhabiting extreme environments may possess features allowing them to tolerate sudden abrupt changes in their environment, a phenomenon often known as ‘adaptability.’ However, ability or success in developing adaptability…1 September, 2015 by Alexander Brearley
In this study, we demonstrate that oceanic vertical velocities can be estimated from individual mooring measurements, even for non-stationary flow. This result is obtained under three assumptions: i. weak diffusion…Read more on Vertical flow in the Southern Ocean estimated from individual moorings
1 September, 2015 by Damien Guihen, Jeremy Robst, Norman Ratcliffe, Peter Enderlein
Penguins, and many other seabirds, often nest in the open in large colonies, and so are amenable to aerial survey. UAVs offer a flexible and inexpensive method of achieving this…Read more on A protocol for the aerial survey of penguin colonies using UAVs
1 September, 2015 by Norman Ratcliffe, Philip Trathan
Mercury emissions have increased over the past decades affecting even remote areas such as Antarctica. As gentoo penguins (Pygoscelis papua) breed on many of the islands surrounding Antarctica, foraging close…1 September, 2015 by Richard Phillips
Microsatellite loci are ideal for testing hypotheses relating to genetic segregation at fine spatio-temporal scales. They are also conserved among closely related species, making them potentially useful for clarifying interspecific…1 September, 2015 by Gareth Marshall, Thomas Bracegirdle
Strong relationships exist between the Southern Annular Mode (SAM) and surface air temperature (SAT) across much of Antarctica. Changes in the SAM will have a profound influence on future Antarctic…1 September, 2015 by Will Goodall-Copestake
Gene duplication and subsequent divergence can lead to the evolution of new functions and lineage specific traits. In sticklebacks, the successive duplication of the mucin-like gene (MUC19) into a tandemly-arrayed,…Read more on The molecular evolution of spiggin nesting glue in sticklebacks
1 September, 2015 by Peter Convey
Systematic surveys of the lichen floras of Schirmacher Oasis (Queen Maud Land, continental Antarctic), Victoria Land (Ross Sector, continental Antarctic) and Admiralty Bay (South Shetland Islands, maritime Antarctic) were compared…Read more on Contrasting patterns in lichen diversity in the continental and maritime Antarctic
1 September, 2015 by Pierre Mathiot
Current ocean models have relatively large errors and biases in the Southern Ocean. The aim of this study is to provide a reanalysis from 1985 to 2006 assimilating sea surface…1 September, 2015 by Hugh Corr
Despite the importance of ice streaming to the evaluation of West Antarctic Ice Sheet (WAIS) stability we know little about mid- to long-term dynamic changes within the Institute Ice Stream…1 September, 2015 by Robert Mulvaney
Climate changes in the North Atlantic region during the last glacial cycle were dominated by the slow waxing and waning of the North American ice sheet as well as by…1 September, 2015 by Jennifer Jackson
Capture-recapture studies offer a powerful tool to assess abundance, survival and population rate of change (λ). A previous capture-recapture study, based on DNA profiles, estimated that the IUCN-listed Endangered Oceania…1 September, 2015 by Jonathan Kingslake
In this paper we undertake a quantitative analysis of the dynamic process by which ice underneath a dry porous debris layer melts. We show that the incorporation of debris-layer airflow…1 September, 2015 by Alex Brisbourne, Andy Smith, Emma Smith, Hamish Pritchard
Flow dynamics of the ice streams that drain the Antarctic Ice Sheet are heavily influenced by processes at the bed. Natural seismic activity generated beneath an ice stream is associated…21 August, 2015 by Hilmar Gudmundsson, Sebastian Rosier
Observations show that the flow of Rutford Ice Stream (RIS) is strongly modulated by the ocean tides, with the strongest tidal response at the 14.77 day tidal period (Msf). This…21 August, 2015 by Kevin Hughes
Antarctic biodiversity and ecosystems are under threat from introduced non-native species. Currently the Antarctic Peninsula and off shore islands are the most invaded areas. Invasions are likely to increase, facilitated…Read more on Status of known non-native species introductions and impacts (updated)
20 August, 2015 by Eric Wolff
An important share of paleoclimatic information is buried within the lowermost layers of deep ice cores. Because improving our records further back in time is one of the main challenges…Read more on Retrieving the paleoclimactic signal from the deeper part of the EPICA Dome C ice core?
18 August, 2015 by David Vaughan
We use the BISICLES adaptive mesh ice sheet model to carry out one, two, and three century simulations of the fast-flowing ice streams of the West Antarctic Ice Sheet. Each…10 August, 2015 by Richard Horne
The introduction of all-electric propulsion satellites is a game-changer in the quest for low-cost access to space. It also raises new questions for satellite manufacturers, operators and the insurance industry…Read more on Space weather concerns for all‐electric propulsion satellites
7 August, 2015
Background Electronic medical record (EMR) systems are increasingly being adopted to support the delivery of health care in developing countries and their implementation can help to strengthen pathways of care…5 August, 2015 by Katrin Linse
Three new species of Sericosura (Pycnogonida: Ammotheidae) are described from recently discovered hydrothermal vents in the East Scotia Ridge, Southern Ocean: Sericosura bamberi sp. nov., S. dimorpha sp. nov. and…5 August, 2015 by Huw Griffiths
The case put by Alexei Smirnov in 2012 is accepted and the order name Synaptida Cuénot is adopted in place of Apodida Brandt. Two new Synaptida species are described for…1 August, 2015 by Joakim Kjellsson
This study finds that the global atmospheric circulation weakens, i.e. transports less mass, by about 5 % per degree of global warming as a result of anthropogenic emissions. This is…Read more on Weakening of the global atmospheric circulation with global warming
1 August, 2015 by Mark Clilverd, Roger Duthie, Roger Duthie
We find that during a large geomagnetic storm in October 2011 the trapped fluxes of >30, >100, and >300 keV outer radiation belt electrons were enhanced at L=3-4 during the…Read more on A case study of electron precipitation fluxes due to plasmaspheric hiss
1 August, 2015 by Paul Holland
Leads are cracks in sea ice that often form due to deformation. During winter months leads expose the ocean to the cold atmosphere resulting in supercooling and the formation of…1 August, 2015 by Kevin Hughes
King George Island, situated in the South Shetland Islands archipelago, is one of the most visited sites in Antarctica. This has contributed to a high density of scientific stations and…1 August, 2015 by Katrin Linse
The ‘scaly-foot gastropod’ is widely recognized as an iconic species of deep-sea hydrothermal vent ecosystems in the Indian Ocean. Uniquely among gastropods, this species carries hundreds of dermal sclerites on…1 August, 2015 by Kevin Newsham
Understanding relationships between environmental changes and soil microbial respiration is critical for predicting changes in soil organic carbon (SOC) fluxes and content. The maritime Antarctic is experiencing one of the…1 August, 2015 by Paul Rodhouse
Malcolm Roy Clarke, FRS (1930–2013) made lasting contributions to cephalopod biology through his productive research programme, his commitment to furthering cephalopod biology and his congenial spirit. His professional legacy includes…1 August, 2015 by Emma Woodfield, Richard Horne
Because of the role of Z-mode emission in the diffusive scattering and resonant acceleration of electrons, we conduct a survey of intensity in the Saturn inner magnetosphere. Z-mode is primarily…1 August, 2015 by Adrian Jenkins, Povl Abrahamsen, Michael Meredith
We present the first densely-sampled hydrographic survey of the Amundsen Sea Polynya (ASP) region, including a detailed characterization of its freshwater distributions. Multiple components contribute to the freshwater budget, including…1 August, 2015 by Paul Rodhouse
Cephalopods (Mollusca: Cephalopoda) play an important role as keystone invertebrates in various marine ecosystems, as well as being a valuable fisheries resource. At the World Malacological Congress, held 21–28 July…1 August, 2015 by Teresa Kyrke-Smith
Observations have long associated ice streams with the presence of meltwater at the bed. More recently, theoretical models have been able to reproduce ice stream behavior as a consequence of…Read more on Subglacial hydrology as a control on emergence, scale, and spacing of ice streams
1 August, 2015 by Povl Abrahamsen, Keith Nicholls
Temperature and salinity data collected around grounded tabular icebergs in Baffin Bay in 2011, 2012, and 2013 indicate wind-induced upwelling at certain locations around the icebergs. These data suggest that…Read more on Wind-driven upwelling around grounded tabular icebergs
30 July, 2015 by Robert Mulvaney
Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling…Read more on Timing and climate forcing of volcanic eruptions for the past 2,500 years
29 July, 2015 by Jean-Baptiste Sallee
Iron availability in the Southern Ocean controls phytoplankton growth, community composition and the uptake of atmospheric CO2 by the biological pump. The KEOPS-2 experiment took place around the Kerguelen plateau…28 July, 2015 by Jean-Baptiste Sallee
The seasonal cycle of phytoplankton biomass in the Southern Ocean (SO) is characterized by a period of rapid accumulation, known as bloom, that is typical of high-latitude regions. Recent studies…Read more on Onset, intensification, and decline of phytoplankton blooms in the Southern Ocean
28 July, 2015 by Mark Clilverd
Electromagnetic ion cyclotron (EMIC) waves have been suggested to be a cause of radiation belt electron loss to the atmosphere. Here simultaneous, magnetically conjugate measurements are presented of EMIC wave…27 July, 2015 by Anna Jones, Howard Roscoe, Neil Brough
Aerosol particle number concentrations have been measured at Halley and Neumayer on the Antarctic coast, since 2004 and 1984 respectively. Sulphur compounds known to be implicated in particle formation and…Read more on Particles and iodine compounds in coastal Antarctica
23 July, 2015 by Eric Wolff, Robert Mulvaney
Relief of iron (Fe) limitation in the Southern Ocean during ice ages, with potentially increased carbon storage in the ocean, has been invoked as one driver of glacial–interglacial atmospheric CO2…
17 July, 2015 by Hoi Ga Chan, Markus Frey
Snow photochemical processes drive production of chemical trace gases in snowpacks, including nitrogen oxides (NOx = NO + NO2) and hydrogen oxide radical (HOx = OH + HO2), which are…
17 July, 2015 by Howard Roscoe, Markus Frey
Mixing ratios of the atmospheric nitrogen oxides NO and NO2 were measured as part of the OPALE (Oxidant Production in Antarctic Lands & Export) campaign at Dome C, East Antarctica…16 July, 2015 by Hilmar Gudmundsson, Jan De Rydt
Following the disintegration of the Larsen B Ice Shelf, Antarctic Peninsula, in 2002, regular surveillance of its ~20 tributary glaciers has revealed a response which is varied and complex in…
16 July, 2015 by Dominic Hodgson
Sub-Antarctic islands are ideally placed to reconstruct past changes in Southern Hemisphere westerly wind behaviour. They lie within their core belt (50–60°S) and the strong winds deliver sea salt ions…13 July, 2015 by Peter Convey
In the Arctic, areas close to seabird colonies are often characterized by exceptionally rich vegetation communities linked with the high nutrient subsidies transported by seabirds from the marine environment to…13 July, 2015 by Richard Phillips
According to niche theory, mechanisms exist that allow co-existence of organisms that would otherwise compete for the same prey and other resources. How seabirds cope with potential competition during the…Read more on Spatial distribution and ecological niches of non-breeding planktivorous petrels
6 July, 2015
The numerous glaciers on the Antarctic Peninsula are highly sensitive to environmental changes, with potential to make a significant contribution to sea-level rise, and yet they have been distinctly under…1 July, 2015 by Rosie Williams, Robert Arthern, Richard Hindmarsh, Richard Hindmarsh
Accurate dynamical models of the Antarctic ice sheet with carefully specified initial conditions and well-calibrated rheological parameters are needed to forecast global sea level. By adapting an inverse method previously…1 July, 2015 by Claire Allen, Dominic Hodgson, Victoria Peck
Recent intensification of wind-driven upwelling of warm upper circumpolar deep water (UCDW) has been linked to accelerated melting of West Antarctic ice shelves and glaciers. To better assess the long…1 July, 2015 by Richard Phillips
The Brown Skua Stercorarius antarcticus lonnbergi is an opportunistic species that displays a high degree of flexibility in foraging tactics. We deployed global positioning system (GPS) and immersion (activity) loggers…1 July, 2015 by Iain Staniland, Philip Trathan
The foraging strategy of many animals is thought to be determined by their past experiences. However, few empirical studies have investigated whether this is true in diving animals. We recorded…Read more on The influence of preceding dive cycles on the foraging decisions of Antarctic fur seals
1 July, 2015 by Richard Phillips
Plastics and other marine debris affect wildlife through entanglement and by ingestion. We assessed the ingestion of marine debris by seven albatross species in the southwest Atlantic by analyzing stomach…Read more on Marine debris ingestion by albatrosses in the southwest Atlantic Ocean
1 July, 2015 by Lloyd Peck, Michael Thorne, Melody Clark, Simon Morley
Selection acts on individuals, specifically on their differences. To understand adaptation and responses to change therefore requires knowledge of how variation is generated and distributed across traits. Variation occurs on…Read more on Variability among individuals is generated at the gene expression level
1 July, 2015 by Hilmar Gudmundsson
Understanding grounding-line dynamics is necessary for predictions of long-term ice-sheet stability. However, despite growing observations of the tidal influence on grounding-line migration, this short-timescale migration is poorly understood, with most…Read more on An improved model for tidally modulated grounding-line migration
1 July, 2015 by Gareth Marshall, Scott Hosking, John Turner, Thomas Bracegirdle, Tony Phillips
In contrast to the Arctic, total sea ice extent (SIE) across the Southern Ocean has increased since the late 1970s, with the annual mean increasing at a rate of 186×103 km2…1 July, 2015 by Richard Phillips
We measured mercury concentrations ([Hg]) and nitrogen stable isotope ratios (δ15N) in the primary feathers of Short-tailed Shearwaters (Puffinus tenuirostris) that were tracked year-round. The [Hg] were highest in 14…1 July, 2015 by Alistair Crame
In Mexico, the Upper Jurassic to lowermost Cretaceous La Casita and coeval La Caja and La Pimienta formations are well-known for their abundant and well-preserved marine vertebrates and invertebrates. The…1 July, 2015 by Richard Horne
Although most studies of the effects of EMIC waves on Earth's outer radiation belt have focused on events in the afternoon sector in the outer plasmasphere or plume region, strong…1 July, 2015 by Jean-Baptiste Sallee
In this study, we document the regional variations of bloom phenology in the Southern Ocean, based on a 13-year product of ocean colour measurements co-located with observation-based estimates of the…Read more on Characterization of distinct bloom phenology regimes in the Southern Ocean
1 July, 2015 by John Turner, Thomas Bracegirdle
Climate model results suggest that future climate change in Antarctica will be accompanied by continued strengthening and poleward contraction of the Southern Ocean westerly wind belt. Paleoclimate records suggest past…Read more on Potential for Southern Hemisphere climate surprises
1 July, 2015
Antarctic crews have been transporting plants and their supporting infrastructure to Antarctic field sites since as early as 1902. More than 46 distinct plant production facilities have, at one time…1 July, 2015 by Mark Clilverd
The EISCAT (European Incoherent SCATer) Scientific Association has provided versatile incoherent scatter (IS) radar facilities on the mainland of northern Scandinavia (the EISCAT UHF and VHF radar systems) and on…1 July, 2015 by Gareth Marshall
The International Surface Pressure Databank (ISPD) is the world's largest collection of global surface and sea-level pressure observations. It was developed by extracting observations from established international archives, through international…Read more on The International Surface Pressure Databank version 2
25 June, 2015 by Andrew Clarke
Antarctic biodiversity is much more extensive, ecologically diverse and biogeographically structured than previously thought. Understanding of how this diversity is distributed in marine and terrestrial systems, the mechanisms underlying its…24 June, 2015 by Katrin Linse
Hydrothermal vents in the Southern Ocean are the physiologically most isolated chemosynthetic environments known. Here, we describe Kiwa tyleri sp. nov., the first species of yeti crab known from the…23 June, 2015 by Emilie Capron, Robert Mulvaney
The stratospheric degradation of chlorofluorocarbons (CFCs) releases chlorine, which is a major contributor to the destruction of stratospheric ozone (O3). A recent study reported strong chlorine isotope fractionation during the…22 June, 2015 by Chester Sands, David Barnes
The Southern Ocean is anomalously rich in benthos. This biodiversity is native, mostly endemic and perceived to be uniquely threatened from climate- and anthropogenically- mediated invasions. Major international scientific effort…18 June, 2015 by Katrin Linse
Introduction The ‘scaly-foot gastropod’ (Chrysomallon squamiferum Chen et al., 2015) from deep-sea hydrothermal vent ecosystems of the Indian Ocean is an active mobile gastropod occurring in locally high densities, and…18 June, 2015 by Philip Trathan
Reproductive investment during the chick-rearing period is an important contributor to lifetime fitness. Key to chick-rearing is the success of parental foraging, as food deliveries affect chick growth and survival…18 June, 2015 by Richard Phillips
Although cephalopods play a critical role in marine food webs both as predators and prey, there is a limited knowledge of several basic aspects of their ecology, including their habitat…Read more on Habitat and trophic ecology of Southern Ocean cephalopods from stable isotope analyses
17 June, 2015 by Markus Frey
During the 2011/12 and 2012/13 austral summers, HCHO was investigated for the first time in ambient air, snow, and interstitial air at the Concordia site, located near Dome C on…16 June, 2015 by David Jones, Hilmar Gudmundsson
Icebergs are a natural hazard to maritime operations in polar regions. Iceberg populations are increasing, as is the demand for access to both Arctic and Antarctic seas. Soon the ability…Read more on Tracking B-31 iceberg with two aircraft deployed sensors
15 June, 2015 by Paul Holland
An established rift in the Larsen C Ice Shelf, formerly constrained by a suture zone containing marine ice, grew rapidly during 2014 and is likely in the near future to…5 June, 2015 by David Pearce
Viruses constitute the most abundant biological entities and a large reservoir of genetic diversity on Earth. Despite the recent surge in their study, our knowledge on their actual biodiversity and…Read more on Biodiversity and distribution of polar freshwater DNA viruses
5 June, 2015 by Markus Frey
The regional climate model MAR was run for the region of Dome C located on the East Antarctic plateau, during Antarctic summer 2011–2012, in order to refine our understanding of…1 June, 2015 by Emma Boland, Emily Shuckburgh
We test the use of a measure to diagnose a sub-mesoscale isopycnal diffusivity by determining the best match between observations of a tracer and simulations with varying small-scale diffusivities. Specifically,…1 June, 2015 by Paul Rodhouse
Some 290 species of squids comprise the order Teuthida that belongs to the molluscan Class Cephalopoda. Of these, about 30–40 squid species have substantial commercial importance around the world. Squid…1 June, 2015 by Peter Convey
The diversity and distribution of Antarctic life has been strongly influenced by climatic events, in particular by large scale extension of ice sheets onto the continental shelf during repeated glacial…1 June, 2015 by Jonathan Kingslake
A model subglacial drainage system, coupled to an ice-dammed reservoir that receives a time-varying meltwater input, is described and analysed. In numerical experiments an ice-marginal lake drains through a subglacial…1 June, 2015 by Adrian Fox
We report on the activities related to the IAG Subcommission 1.3f “Regional Reference Frame for Antarctica”. Campaign-style GPS observations have been carried out since 1995. Based on the Bernese GNSS…Read more on The Antarctic Regional GPS Network Densification: Status and Results
1 June, 2015 by Roger Worland
Seasonal changes in the FA composition of triacylglycerols and phospholipids prepared from the whole body of non-diapausing and diapausing fifth instar larvae of Ostrinia nubilalis, Hubn. (Lepidoptera: Crambidae) were determined…1 June, 2015 by Zhaomin Wang
Carbon (C) sequestration following afforestation is regarded as economically, politically, and technically feasible for fighting global warming, whereas the afforested area which will contribute more efficiently as sinks for CO2…Read more on Effects of regional afforestation on global climate
1 June, 2015 by Eugene Murphy, Emma Young, Mark Belchier, Michael Meredith
Understanding the key drivers of population connectivity in the marine environment is essential for the effective management of natural resources. Although several different approaches to evaluating connectivity have been used,…1 June, 2015 by Philip Trathan
The relationship between population structure and demographic history is critical to understanding microevolution and for predicting the resilience of species to environmental change. Using mitochondrial DNA from extant colonies and…