Found 14035 items
1 January, 2010 by Teal Riley
Silicic volcanism at c. 168 Ma has been identified previously on the Antarctic Peninsula, and the Mapple Formation, which includes those volcanic rocks, has been defined and documented from one…1 January, 2010 by Michael Meredith
By connecting the ocean basins and the upper and lower limbs of the ocean overturning circulation, the Southern Ocean plays a critical role in the global ocean circulation, biogeochemical cycles…1 January, 2010 by Dominic Hodgson, Huw Griffiths, Michael Thorne, Stephen Roberts
Glaciers in small mountain cirques on South Georgia respond rapidly and sensitively to changes in South Atlantic climate. The timing and rate of their deglaciation can be used to examine…1 January, 2010 by Paul Rodhouse
This manuscript was produced as an introduction to this publication emanating from CIAC '09, the recent triennial symposium of the Cephalopod International Advisory Council. Given the importance of one of…1 January, 2010 by Paul Rodhouse
Satellite-tracked squid predators and fish-finding acoustics were used to locate squid concentrations at the Antarctic Polar Front, then to sample them with a midwater trawl. Near-surface hauls were dominated by…1 January, 2010 by Simeon Hill
There is growing interest in models of marine ecosystems that deal with the effects of climate change through the higher trophic levels. Such end-to-end models combine physicochemical oceanographic descriptors and…1 January, 2010 by Eric Wolff
Diatom assemblages in marine cores and sea salt deposition fluxes in ice cores have been used as sea ice proxies in the southern hemisphere. Here, a marine and an ice…1 January, 2010
Zonal and meridional winds have been measured in the upper mesosphere and lower thermosphere at polar latitudes using two ground-based meteor radars. One radar is located at Rothera (68° S,…1 January, 2010 by Annette Scheffer, Philip Trathan
Marine predators are thought to utilise oceanic features adjusting their foraging strategy in a scale-dependent manner. Thus, they are thought to dynamically alter their foraging behaviour in response to environmental…1 January, 2010 by Geraint Tarling
Early feeding studies on Meganyctiphanes norvegica described the morphology of the feeding appendages and the actual process of food uptake and digestion. Insights into diurnal, seasonal and ontogenetic pattern in…Read more on Food and feeding in northern krill (Meganyctiphanes norvegica sars)
1 January, 2010 by Michael Meredith
Climate change will alter marine ecosystems; however, the complexity of the food webs, combined with chronic undersampling, constrains efforts to predict their future and to optimally manage and protect marine…Read more on How do polar marine ecosystems respond to rapid climate change?
1 January, 2010 by Richard Hindmarsh, Richard Hindmarsh
Free-surface thin-film flows can principally be described by two types of models. Lubrication models assume that shear stresses are dominant in the force balance of the flow and are appropriate…1 January, 2010 by Gareth Marshall
Over the last four decades there has been a trend to earlier summer breakup of the sea ice in western Hudson Bay, Canada. This sea ice is critical for the…Read more on A step-change in the date of sea-ice breakup in western Hudson Bay
1 January, 2010 by Andy Smith, David Vaughan
The basic theory of crevasse formation suggests that crevasses initiate at or near the surface. However, due to variations in stress with depth, it has been suggested that it is…1 January, 2010 by Geraint Tarling, Will Goodall-Copestake
Background: All crustaceans periodically moult to renew their exoskeleton. In krill this involves partial digestion and resorption of the old exoskeleton and synthesis of new cuticle. Molecular events that underlie…1 January, 2010
A state-of-the-art complex marine ecosystem model, PlankTOM5 2, simulating the distribution of five plankton functional types (PFTs, mixed phytoplankton, diatoms, coccolithophores, micro and mesozooplankton), was implemented separately in two medium…1 January, 2010 by Pierre Dutrieux
[1] We present results from the first zonal transect of iron, aluminum, and manganese conducted from the western source region of the Equatorial Undercurrent (EUC) to the central equatorial Pacific.…1 January, 2010 by Nigel Meredith, Richard Horne
This paper analyses a unique set of continuous high-quality well-calibrated observations of natural ELF/VLF radio waves, in the range 0.3-10 kHz, made at Halley Research Station, Antarctica (76 degrees S,27…1 January, 2010 by Michael Meredith
The transports associated with the Subantarctic Front (SAF) and the Polar Front (PF) account for the majority of the volume transport of the Antarctic Circumpolar Current (ACC). After passing through…Read more on The flow of the Antarctic Circumpolar Current over the North Scotia Ridge
1 January, 2010 by Iain Staniland
Foragers show adaptive responses to changes within their environment, and such behavioural plasticity can be a significant driving force in speciation. We investigated how lactating Antarctic fur seals, Arctocephalus gazella,…1 January, 2010
New high-resolution deuterium excess (d) data from the two EPICA ice cores drilled in Dronning Maud Land (EDML) and Dome C (EDC) are presented here. The main moisture sources for…1 January, 2010 by Lloyd Peck
Horizon scanning identifies emerging issues in a given field sufficiently early to conduct research to inform policy and practice. Our group of horizon scanners, including academics and researchers, convened to…Read more on A horizon scan of global conservation issues for 2010
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 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 Michael Thorne, Roger Worland, Melody Clark
Arthropods have evolved a number of different adaptations to survive extreme environmental temperatures including, in some regions, over-wintering temperatures well below 0°C. One of the less common adaptations to surviving…Read more on Cryoprotective dehydration: clues from an insect
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
23 December, 2009 by Hilmar Gudmundsson
We propose a new approach to indirectly estimate basal properties of ice streams, i.e. bedrock topography and basal slipperiness, from observations of surface topography and surface velocities. We demonstrate how…15 December, 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,…9 December, 2009 by Robert Larter
The Amundsen Sea Embayment is the most rapidly changing sector of the West Antarctic Ice Sheet and contains enough ice to raise global sea level by 1.2 m. Over the…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
16 November, 2009 by Markus Frey
The nitrogen (δ15N) and triple oxygen (δ17O and δ18O) isotopic composition of nitrate (NO3−) was measured year-round in the atmosphere and snow pits at Dome C, Antarctica (DC, 75.1° S,…11 November, 2009
To investigate possible couplings between planetary waves and the semidiurnal tide (SDT), this work examines the statistical correlations between the SDT amplitudes observed in the Northern Hemisphere (NH) mesosphere and…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 September, 2009
We demonstrate that global satellite products can be used to evaluate climate model soil moisture predictions but conclusions should be drawn with care. The quality of a limited area climate…1 September, 2009
The coupling processes in the middle atmosphere have been a subject of intense research activity because of their effects on atmospheric circulation, structure, variability, and the distribution of chemical constituents.…17 July, 2009 by Anna Jones, Eric Wolff, Gareth Marshall, Howard Roscoe, Neil Brough
The source of bromine that drives polar boundary layer ozone depletion events (ODEs) is still open to some debate. While ODEs are generally noted to form under conditions of a…Read more on BrO, blizzards, and drivers of polar tropospheric ozone depletion events
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
20 May, 2009 by Markus Frey
Atmospheric hydroperoxides (ROOH) were measured at Summit, Greenland (72.97 degrees N, 38.77 degrees W) in summer 2003 (SUM03) and spring 2004 (SUM04) and South Pole in December 2003 (SP03). The…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…13 May, 2009 by Andy Smith, David Vaughan, Hilmar Gudmundsson, Hamish Pritchard
Pine Island Glacier, Antarctica, has been undergoing several related changes for at least two decades; these include acceleration, thinning and grounding line retreat. During the first major ground-based study between…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,…26 March, 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…25 March, 2009 by Jamie Oliver, Kevin Hughes
Science has always been at the centre of human endeavour in Antarctica. It is just over 50 years since the International Geophysical Year (1957-58) established many of the long-term research…Read more on Understanding Antarctica – 50 years of British Scientific Monitoring (1959-2009)
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…11 February, 2009
We perform two superposed epoch analyses of the auroral evolution during substorms using the FUV instrument on the Imager for Magnetopause-to-Aurora Global Explorer ( IMAGE) spacecraft. The larger of the…6 February, 2009
The multi-scale nature and climate noise properties of teleconnection indices are examined by using the Empirical Mode Decomposition (EMD) procedure. The EMD procedure allows for the analysis of non-stationary time…3 February, 2009 by Howard Roscoe
A new climatology of stratospheric BrO profiles based on a parameterization using dynamical and chemical indicators has been developed, with the aim to apply it to the retrieval of tropospheric…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