Showing 11332 items
1 January, 2010
We examine global phylogeography of the two forms of giant petrel Macronectes spp. Although previously considered to be a single taxon, and despite debate over the status of some populations…Read more on Speciation and phylogeography of giant petrels Macronectes
1 January, 2010 by Keith Makinson
The Eastern Weddell Ice Shelves (EWIS) are believed to modify the water masses of the coastal current and thus preconditions the water mass formation in the southern and western Weddell…1 January, 2010 by Andy Smith
The empirical Equation of State (EOS) allows the calculation of the density of water in dependence of salinity, temperature, and pressure. Water density is an important quantity to determine the…1 January, 2010 by Guy Hillyard, Michael Thorne, Melody Clark
Harpagifer antarcticus (the Antarctic plunderfish), a shallow-water benthic fish distributed around the Antarctic Peninsula, is a member of the notothenioid family, one of whose adaptations to the cold waters of…1 January, 2010 by Nigel Meredith, Richard Horne
Earth's diffuse aurora occurs over a broad latitude range(1) and is primarily caused by the precipitation of low-energy (0.1-30-keV) electrons originating in the central plasma sheet(2), which is the source…Read more on Scattering by chorus waves as the dominant cause of diffuse auroral precipitation
1 January, 2010 by Adrian Jenkins, Keith Makinson, Pierre Dutrieux
Sub-ice shelf circulation and freezing/melting rates in ocean general circulation models depend critically on an accurate and consistent representation of cavity geometry. Existing global or pan-Antarctic data sets have turned…1 January, 2010 by Peter Convey
Collembola are one of the few hexapod groups adapted to live in the harsh environmental conditions of Antarctic terrestrial ecosystems. Diversity is limited to a few species that can be…1 January, 2010 by Peter Convey
Friesea grisea is the only springtail species currently described from both East (Victoria Land) and West Antarctica (Antarctic Peninsula), although levels of genetic divergence between the two regions suggest the…1 January, 2010 by Philip Trathan
In this paper we review evidence for, and anticipated consequences of, climate change in Antarctic marine communities, examining the potential impacts on invertebrates and vertebrates alike and exploring plausible outcomes…Read more on Climate change and the Antarctic marine ecosystem: an essay on management implications
1 January, 2010 by Guy Hillyard, Lloyd Peck, Michael Thorne, Melody Clark
Our ability to predict animal responses to temperature changes is currently limited and more sensitive methods of identifying mechanisms, limits and thresholds are required. Antarctic marine ectotherms are excellent candidates…Read more on Transcriptional response to heat stress in the Antarctic bivalve Laternula elliptica
1 January, 2010 by Dominic Hodgson
Both ground-based and satellite data show that parts of Antarctica have entered a period of rapid climate change, which already affects the functioning and productivity of limnetic ecosystems. To predict…1 January, 2010 by Dominic Hodgson
Understanding the enormous diversity of microbes, their multiple roles in the functioning of ecosystems, and their response to large-scale environmental and climatic changes, are at the forefront of the international…Read more on Evidence for widespread endemism among Antarctic micro-organisms
1 January, 2010 by Geraint Tarling
We present observations of zooplankton diel vertical migration (DVM) over a period of 2 yr in an ice-free and a seasonally ice-covered Arctic fjord. The contrasting environments permitted assessment of…1 January, 2010
The paper will analyze over 50 years of science publications by British Antarctic Survey to establish the pattern of annual publications, changes in disciplinary output and how these might be…Read more on Trends and patterns in publication of Antarctic science
1 January, 2010 by Claire Waluda, Michael Dunn, Susan Gregory
The number of Antarctic fur seals Arctocephalus gazella hauled out at Signy Island in the South Orkneys was monitored annually between 1977 and 2008. Over the study period seal abundance…1 January, 2010 by Philip Trathan
In the wild, seabirds dive longer than their theoretical aerobic dive limit (oxygen store divided by oxygen consumption rate). One of the potential explanations for this is that when descending…1 January, 2010 by Victoria Peck
Growth increment analysis coupled with stable isotopic data (δ18O/δ13C) from Early Pliocene (ca 4.7 Ma) Austrochlamys anderssoni from shallow marine sediments of the Cockburn Island Formation, northern Antarctic Peninsula, suggest…Read more on Sea ice extent and seasonality for the Early Pliocene northern Weddell Sea
1 January, 2010 by Eric Wolff, Louise Sime, Robert Mulvaney
The EPICA ice core from Dome C extends 3259 m in depth, and encompasses 800 ka of datable and sequential ice. Numerous chemical species have been measured along the length…1 January, 2010 by Eric Wolff
The oxygen-isotope records from Greenland ice cores show a very strong, reproducible pattern of alternation between warm Greenland Interstadials (GI) and cold Greenland Stadials (GS) at millennial-scale during the last…Read more on Millennial-scale variability during the last glacial: the ice core record
1 January, 2010 by Roger Worland
Understanding the mechanisms by which aphids survive low temperature is fundamental in forecasting the risk of pest outbreaks. Aphids are chill susceptible and die at a temperature close to that…Read more on Pre-freeze mortality in three species of aphids from sub-Antarctic Marion Island
1 January, 2010 by Roger Worland
During the late 1960s, larvae of the flightless midge Eretmoptera murphyi Schaeffer were accidentally transferred from the sub-Antarctic island of South Georgia to Signy Island in the maritime Antarctic. Higher…Read more on Eretmoptera murphyi: pre-adapted to survive a colder climate
1 January, 2010 by Philip Trathan
Streaked Shearwaters (Calonectris leucomelas) breed in temperate regions of East and Southeast Asia and have been thought to migrate to tropical regions near the Equator after breeding. We documented the…1 January, 2010 by Claire Waluda, Iain Staniland, Martin Collins, Philip Trathan
Antarctic fur seals Arctocephalus gazella and macaroni penguins Eudyptes chrysolophus are the two main land-based krill Euphausia superba consumers in the northern Scotia Sea. Using a combination of concurrent at-sea…27 December, 2009 by Amelie Kirchgaessner, Andrew Orr, David Vaughan, Gareth Marshall, John King, John Turner, Steve Colwell, Thomas Bracegirdle, Thomas Lachlan-Cope, Tony Phillips
The lowest recorded air temperature at the surface of the Earth was a measurement of −89.2°C made at Vostok station, Antarctica, at 0245 UT on 21 July 1983. Here we…Read more on Record low surface air temperature at Vostok Station, Antarctica
17 November, 2009
Efforts to control climate change require the stabilization of atmospheric CO2 concentrations. This can only be achieved through a drastic reduction of global CO2 emissions. Yet fossil fuel emissions increased…Read more on Trends in the sources and sinks of carbon dioxide
28 October, 2009 by Vsevolod Afanasyev
When searching for prey, animals should maximize energetic gain, while minimizing energy expenditure by altering their movements relative to prey availability. However, with increasing amounts of marine debris, what once…1 October, 2009 by Philip Trathan
Albatrosses fly many hundreds of kilometers across the open ocean to find and feed upon their prey. Despite the growing number of studies concerning their foraging behaviour, relatively little is…1 October, 2009 by Liz Thomas, Thomas Bracegirdle
We present a new 150-year, high-resolution, stable isotope record (delta O-18) from the Gomez ice core, drilled on the data sparse south western Antarctic Peninsula, revealing a similar to 2.7…Read more on Ice core evidence for significant 100-year regional warming on the Antarctic Peninsula
30 September, 2009 by Nigel Meredith, Richard Horne
Relativistic (>1 MeV) electron flux increases in the Earth's radiation belts are significantly underestimated by models that only include transport and loss processes, suggesting that some additional acceleration process is…18 September, 2009 by Povl Abrahamsen
Shipboard hydrography and current profiles collected in 2003 and time series from moored current meters deployed in late 1990s are analyzed to study the variability of mixing in the southeastern…Read more on Mixing on the continental slope of the southern Weddell Sea
2 September, 2009 by Gareth Chisham, Mervyn Freeman
We present a technique to measure the magnetic field-aligned vorticity of meso-scale plasma flows in the F-region ionosphere using line-of-sight velocity measurements made by the Super Dual Auroral Radar Network…1 September, 2009 by Andrew Clarke, David Barnes, Huw Griffiths, Michael Meredith, Susie Grant
The Antarctic seabed has traditionally been regarded as cold and thermally stable, with little spatial or seasonal variation in temperature. Here we demonstrate marked spatial variations in continental shelf seabed…1 July, 2009
Migratory marine vertebrates move annually across remote oceanic water masses crossing international borders. Many anthropogenic threats such as overfishing, bycatch, pollution or global warming put millions of marine migrants at…Read more on Understanding oceanic migrations with intrinsic biogeochemical markers
16 May, 2009 by Elaina Ford
Long-period planetary wave data derived from meteor wind observations recorded over a 12-year period with the SuperDARN radar at Halley, Antarctica, are presented and compared with the phase of the…1 May, 2009 by Gabriele Stowasser, Martin Collins
To investigate the trophic ecology of two of the dominant families of deep-sea fish (Macrouridae and Moridae) fatty acid and stable isotope analyses were applied to liver and muscle samples…27 April, 2009 by Eric Wolff, Liz Thomas, Robert Mulvaney
Large and abrupt temperature oscillations during the last glacial period, known as Dansgaard‐Oeschger (DO) events, are clearly observed in the Greenland ice core record. Here we present a new high‐resolution…23 April, 2009 by Andrew Orr, Gareth Marshall, John Turner, Michael Meredith, Thomas Bracegirdle, Thomas Lachlan-Cope, Zhaomin Wang
Based on a new analysis of passive microwave satellite data, we demonstrate that the annual mean extent of Antarctic sea ice has increased at a statistically significant rate of 0.97%…2 April, 2009 by Povl Abrahamsen, Michael Meredith
We investigate the freshwater composition of the shelf and slope of the Arctic Ocean north of the New Siberian Islands using geochemical tracer data (δ18O, Ba, and PO4*) collected following…1 April, 2009 by John King
This article describes the development and evaluation of the U.K.'s new High-Resolution Global Environmental Model (HiGEM), which is based on the latest climate configuration of the Met Office Unified Model,…25 March, 2009 by Richard Hindmarsh, Richard Hindmarsh
Accurate computation of ice-stream location and dynamics is a key aspiration for theoretical glaciology. Ice-sheet models with thermo-viscous coupling have been shown to exhibit stream-like instabilities using shallow-ice approximation mechanics,…25 March, 2009
Source regions for the westward propagating zonal wavenumber one and three components of the semidiurnal tide observed in the summer mesosphere and lower thermosphere over Antarctica are identified by correlating…Read more on Source regions for Antarctic MLT non-migrating semidiurnal tides
24 March, 2009 by Kevin Newsham
Understanding and accurately predicting the fate of carbon and nitrogen in the terrestrial biosphere remains a central goal in ecosystem science. Amino acids represent a key pool of C and…Read more on Soil organic nitrogen mineralization across a global latitudinal gradient
3 March, 2009 by Povl Abrahamsen
Microstructure and hydrographic observations, during September 2007 in the boundary current on the East Siberian continental slope, document upper ocean stratification and along-stream water mass changes. A thin warm surface…Read more on Vertical mixing at intermediate depths in the Arctic boundary current
25 February, 2009 by Gareth Chisham, Mervyn Freeman
In this paper we determine the probability of substorm onset as a function of open magnetic flux in the magnetosphere by comparing the occurrence distribution of open flux observed at…1 January, 2009 by Richard Phillips
Seabirds are often advocated as biomonitors for marine contaminants such as mercury (Hg). However, contaminant levels can vary widely depending on among-individual and among-species variation in foraging preferences and physiology,…1 January, 2009 by Richard Phillips
The diet of brown skuas (Catharacta antarctica lonnbergi) on Bird Island, South Georgia was assessed using a combination of stable isotope analysis (SIA) and mixing model techniques. We found evidence…1 January, 2009
During the Middle Pliocene, the Earth experienced greater global warmth compared with today, coupled with higher atmospheric CO2 concentrations. To determine the extent to which the Middle Pliocene can be…1 January, 2009 by Gareth Chisham, Mervyn Freeman
We present an analysis of 8 years of meridional line-of-sight ionospheric plasma velocity measurements from the Halley SuperDARN radar which investigates the effect of the interplanetary magnetic field (IMF) clock…Read more on IMF clock angle control of multifractality in ionospheric velocity fluctuations
1 January, 2009
The Indo-Pacific Warm Pool (IPWP) is thought to play a key role in the propagation and amplification of climate changes through its influence on the global distribution of heat and…1 January, 2009 by Philip Trathan
We report the characterization of 25 microsatellite loci isolated from the macaroni penguin (Eudyptes chrysolophus). Thirteen loci were arranged into four multiplex sets for future genetic studies of macaroni penguin…1 January, 2009
The empirical dependence of turbulence Prandtl number (Pr) on gradient Richardson number (Ri) is presented, derived so as to avoid the effects of self-correlation from common variables. Linear power relationships…1 January, 2009
Despite much research on Euphausia superba, estimates of their total biomass and production are still very uncertain. Recently, circumpolar krill databases, combined with growth models and revisions in acoustics have…Read more on A re-appraisal of the total biomass and annual production of Antarctic krill
1 January, 2009
To evaluate and extend the record of decadal climate variability, we present a synthesis of 23 coral oxygen isotope records from the tropical Indo-Pacific that extends back to A. D.…Read more on Intensified decadal variability in tropical climate during the late 19th century
1 January, 2009 by Martin Collins
A severe scarcity of life history and population data for deep-water fishes is a major impediment to successful fisheries management. Long-term data for non-target species and those living deeper than…1 January, 2009 by Eric Wolff
Quaternary Climate: From Pole to Pole—EPICA Open Science Conference; Venice, Italy, 10–13 November 2008; The European Project for Ice Coring in Antarctica (EPICA) has provided unique paleoclimatic data and is…Read more on Toward a better understanding of climate of the past million years
1 January, 2009
The asynchronous relationship between millennial-scale temperature changes over Greenland and Antarctica during the last glacial period has led to the notion of a bipolar seesaw which acts to redistribute heat…Read more on Interhemispheric Atlantic seesaw response during the last deglaciation
1 January, 2009 by David Barnes
One of the most ubiquitous and long-lasting recent changes to the surface of our planet is the accumulation and fragmentation of plastics. Within just a few decades since mass production…Read more on Accumulation and fragmentation of plastic debris in global environments
1 January, 2009 by David Barnes, Huw Griffiths
Toleration, adaptation, migration or extinction are the options for species making up Southern Ocean (SO) shelf biodiversity, in response to accelerating change (e.g. warming), Physiological evidence suggests few organisms may…1 January, 2009 by David Barnes, Huw Griffiths, Katrin Linse
We ask how biodiverse is a polar archipelago; how this faunal richness is spread across marine, intertidal, freshwater, terrestrial and parasitic realms; and how fast species are accumulated with increased…1 January, 2009 by Andy Smith, David Vaughan, Keith Nicholls
The Antarctic Peninsula has warmed faster than the global average rate of warming during the last century. Due to limited availability of long term meteorological records, the geographical extent of…Read more on Rapid recent warming on Rutford Ice Stream, West Antarctica, from borehole thermometry
1 January, 2009 by Mark Belchier, Peter Fretwell
A new South Georgia Bathymetric Dataset (SGDB) was compiled from a variety of primary sources including multi-beam swath bathymetry. Sea floor area (km(2)1 January, 2009 by Dominic Hodgson, Claus-Dieter Hillenbrand, James Smith, Robert Larter, Stephen Roberts
The Antarctic Peninsula is one of the three fastest warming regions on Earth. Here we review Holocene proxy records of marine and terrestrial palaeoclimate in the region, and discuss possible…Read more on Mechanisms of Holocene palaeoenvironmental change in the Antarctic Peninsula region
1 January, 2009 by Dominic Hodgson
Reconstructing the former dimensions and deglacial history of the Antarctic Ice Sheet along with Antarctic paleoclimate is important for understanding forcing mechanisms of ice sheet change. Here, we review briefly…Read more on Antarctic ice sheet and climate history since the Last Glacial Maximum
1 January, 2009
Free-living nematodes constitute an important component of estuarine and marine benthic ecosystems. Some marine and soil nematodes are known to harbor microbes, including symbiotic bacteria and fungi, in their external…1 January, 2009
Glaciated landscapes consist of complex assemblages of landforms resulting from ice flow dynamic regimes and ice-sheet history, superimposed over, and in turn modifying, preglacial topography, lithology and geological structure. insights…1 January, 2009 by Hilary Blagbrough
The British Antarctic Survey is the custodian of more than 57,000 Antarctic fossils, of which some 2,500 are Type & Figured specimens. In addition to these, the geological collections include…Read more on In from the cold: an overview of the British Antarctic Survey fossil collections
1 January, 2009 by William Block
Antarctic fellfields present organisms with a heterogeneous habitat characterised by a wide variety of environmental stresses. These include low temperatures, limited moisture availability, frequent and often rapid freeze-thaw and hydration-dehydration…Read more on Strategies of survival and resource exploitation in the Antarctic fellfield ecosystem
1 January, 2009 by Michael Meredith, Sally Thorpe
The increasing need for continuous monitoring of the world oceans has stimulated the development of a range of autonomous sampling platforms. One novel addition to these approaches is a small,…1 January, 2009
It has been suggested that, during the Pliocene (ca 5–1.8Ma), an El Niño state existed as a permanent rather than an intermittent feature; that is, the tropical Pacific Ocean was…Read more on El Niño–Southern Oscillation, Pliocene climate and equifinality
1 January, 2009 by Pierre Dutrieux
A combination of 15N2 labeling, Tyramide Signal Amplification–Fluorescent in Situ Hybridization (TSA-FISH) assay, and chemical analyses were performed along a trophic gradient (8000 km) in the equatorial Pacific. Nitrogen fixation…1 January, 2009 by Nigel Meredith
A brief overview is given of the history of plasmaspheric hiss research, particularly in the context of the recent work by Bortnik et al. (2008) indicating that chorus could be…Read more on Plasmaspheric hiss overview and relation to chorus
1 January, 2009 by Philip Trathan
Although penguins are key marine predators from the Southern Ocean, their migratory behaviour during the inter-nesting period remains widely unknown. Here, we report for the first time, to our knowledge,…1 January, 2009 by Andrew Clarke, Lloyd Peck
Most marine benthic macroinvertebrate species reproduce via a larval phase but attempts to explain the occurrence of different larval strategies (feeding or non-feeding, pelagic or benthic) in different habitats have…1 January, 2009 by Thomas Bracegirdle
The dynamics of a polar low are examined using a piecewise potential vorticity (PV) inversion method. In previous studies of this and other polar lows, structural evolution has been described…Read more on The dynamics of a polar low assessed using potential vorticity inversion
1 January, 2009 by Katrin Linse
The aim of this study is to compare the depth distributions of four major Southern Ocean macrobenthic epi- and infaunal taxa, the Bivalvia, Gastropoda, Isopoda, and Polychaeta, from subtidal to…1 January, 2009 by Kevin Newsham
PCR amplification of ITS1-5.8S-ITS2 regions of rDNA followed by cloning was used to determine the fungi present in soil from three sites at Mars Oasis in the southern maritime Antarctic.…Read more on Soil fungal community composition at Mars Oasis, a southern maritime Antarctic site
1 January, 2009 by Markus Frey
An analysis of 96 snow pit and ice cores distributed over the Greenland ice sheet is used to determine the main drivers of variability in the preserved records of nitrate…1 January, 2009 by Lloyd Peck
Extrinsic neural and humoral influences on heart rate (fH) and ventilation frequency (fV) were examined following varying periods of post-surgical recovery in eight related Antarctic fish species inhabiting an array…Read more on Heart rate and ventilation in Antarctic fishes are largely determined by ecotype
1 January, 2009 by Richard Phillips
This is the first study using geolocators (global location sensing, GLS) to track the movements of a pelagic tropical seabird. We used GLS to describe at-sea distribution and activity patterns…1 January, 2009
Similarity analysis is used to identify the control parameter RA for the subset of avalanching systems that can exhibit self-organized criticality SOC. This parameter expresses the ratio of driving to…Read more on Macroscopic control parameter for avalanche models of bursty transport
1 January, 2009
The paradigm of self-organized criticality (SOC) has found application in understanding scaling and bursty transport in driven, dissipative plasmas. SOC is, however, a limiting process that occurs as the ratio…Read more on Avalanching systems under intermediate driving rate
1 January, 2009 by Richard Horne
A three dimensional ray tracing of whistler-mode chorus is performed in a realistic magnetosphere using the HOTRAY code. A variety of important propagation characteristics are revealed associated with azimuthal density…1 January, 2009 by Richard Horne
The HOTRAY code is used to evaluate the path integrated gain of electromagnetic ion cyclotron (EMIC) waves as a function of frequency in two propagation bands above the O+ and…1 January, 2009 by Michael Dunn, Peter Convey
Soil bacterial diversity at environmentally distinct locations on Signy Island, South Orkney Islands was examined using the denaturing gradient gel profiling approach. A range of chemical variables in soils at…1 January, 2009 by Lloyd Peck, Melody Clark
The ability to understand and predict the effects of environmental stress on biodiversity is becoming increasingly important in our changing environment. Antarctic marine species are some of the most stenothermal…1 January, 2009 by Lloyd Peck, Melody Clark
The Antarctic limpet, Nacella concinna, exhibits the classical heat shock response, with up-regulation of duplicated forms of the inducible heat shock protein 70 (HSP70) gene in response to experimental manipulation…1 January, 2009 by Guy Hillyard, Michael Thorne, Roger Worland, Melody Clark
Background: Insects provide tractable models for enhancing our understanding of the physiological and cellular processes that enable survival at extreme low temperatures. They possess three main strategies to survive the…1 January, 2009 by Mark Clilverd
We analyze in detail the February 2004 Global Ozone Monitoring by Occultation of Stars (GOMOS) NO2 observations in the northern polar latitudes during the springtime descent of NOx from the…1 January, 2009 by Mark Clilverd, Neil Cobbett
[1] The Antarctic-Arctic Radiation-belt (Dynamic) Deposition-VLF Atmospheric Research Konsortium (AARDDVARK) provides a network of continuous long-range observations of the lower ionosphere in the polar regions. Our ultimate aim is to…