Found 14065 items
1 January, 2010 by Tracy Moffat-Griffin
An imaging riometer uses the absorption of cosmic radio noise as a means of measuring electron density enhancements in the D region of the ionosphere. It employs a ground-based phased…Read more on Calibrating an imaging riometer: determination of the true beam azimuth angle position
1 January, 2010 by Howard Roscoe
Measurements of NO and NO2 were made at a surface site (55.28 degrees N, 77.77 degrees W) near Kuujjuarapik, Canada during February and March 2008. NOx mixing ratios ranged from…1 January, 2010 by Lloyd Peck, Melody Clark, Simon Morley
To fully understand how species distributions will respond to changing environments it is essential to understand the mechanisms underlying variation in animal performance and the relative importance of different ecological…1 January, 2010 by Iain Staniland
In order to investigate the extent to which Perfluorinated Contaminants (PFCs) have permeated the Southern Ocean food web to date, a range of Antarctic, sub-Antarctic and Antarctic-migratory biota were analysed…1 January, 2010 by Jaume Forcada
A major challenge in ecology is to understand the impact of increased environmental variability on populations and ecosystems. To maximize their fitness in a variable environment, life history theory states…Read more on Bet-hedging response to environmental variability, an intraspecific comparison
1 January, 2010 by Kevin Newsham
The biology and ecology of Cephaloziella varians, the most widespread and abundant liverwort in Antarctica, are reviewed. A description of the species is given, together with information on its geographical…Read more on The biology and ecology of the liverwort Cephaloziella varians in Antarctica
1 January, 2010 by Kevin Newsham
The leafy liverwort Lophozia excisa, which is colonised by basidiomycete fungi in other biomes and which evidence suggests may be colonised by mycorrhizal fungi in Antarctica, was sampled from L,onie…1 January, 2010 by David Pearce, Kevin Newsham
Bacterial community composition was determined by culture-independent PCR-based methods in two soils differing markedly in their water, C, N and P contents sampled from Mars Oasis on Alexander Island, western…1 January, 2010 by Ed King, Richard Hindmarsh, Robert Larter, Richard Hindmarsh
The submarine glacial geomorphology and sedimentology of the cross-shelf troughs and the adjacent continental slope around the Antarctic Peninsula and West Antarctica have been the focus of a series of…1 January, 2010 by David Barnes, Lloyd Peck, Simon Morley
Pronounced seasonality in photoperiod and phytoplankton availability drives key physiological processes in many Antarctic primary consumers. To test the hypothesis that carnivores would be less markedly affected by environmental seasonality…Read more on Seasonal physiology and ecology of Antarctic marine benthos predators and scavengers
1 January, 2010 by Carlos Martin Garcia
Calving from tidewater glaciers and ice shelves accounts for around half the mass loss from both polar ice sheets, yet the process is not well represented in prognostic models of…1 January, 2010 by Adrian Jenkins, Deb Shoosmith
We demonstrate the first use of marine mammal dive-depth data to improve maps of bathymetry in poorly sampled regions of the continental shelf. A group of 57 instrumented elephant seals…Read more on Seals map bathymetry of the Antarctic continental shelf
1 January, 2010 by Anna Jones, David Pearce, Kevin Hughes, Thomas Lachlan-Cope
A study of air-borne microbial biodiversity over an isolated scientific research station on an ice-shelf in continental Antarctica was undertaken to establish the potential source of microbial colonists. The study…Read more on Biodiversity of air-borne microorganisms at Halley station Antarctica
1 January, 2010 by Andrew Clarke, Andrew Fleming, David Barnes, Lloyd Peck
Feedbacks on climate change so far identified are predominantly positive, enhancing the rate of change. Loss of sea-ice, increase in desert areas, water vapour increase, loss of tropical rain forest…Read more on Negative feedback in the cold: ice retreat produces new carbon sinks in Antarctica
1 January, 2010 by Lloyd Peck
Geographical variations in animal characters are one of the main subjects for study in macroecology. Variation with latitude has received special interest. Articulated brachiopods are possibly the commonest macrofossil with…Read more on Variation in size of living articulated brachiopods with latitude and depth
1 January, 2010 by Lloyd Peck, Melody Clark, Simon Morley
Animals can respond to temperature change by the following means: using physiological flexibility (including acclimation); or adapting; or migrating, with acclimation proposed as the major mechanism dictating prospects for survival…Read more on Poor acclimation capacities in Antarctic marine ectotherms
1 January, 2010 by Victoria Peck
To date, no conclusive evidence has been identified for intermediate or deep water cooling associated with the > 1 parts per thousand benthic delta O-18 increase at the Eocene-Oligocene transition…1 January, 2010 by Richard Phillips
The United Nations, under the auspices of the Convention on Biological Diversity (CBD) has proclaimed 2010 as the International Year of Biodiversity. This has led to numerous initiatives to highlight…Read more on Eradications of invasive mammals from islands: why, where, how and what next?
1 January, 2010 by Richard Phillips
Fisheries are increasingly adopting ecosystem approaches to better manage impacts on non-target species. Although deliberate dumping of plastics at sea is banned, not all fisheries legislation prohibits discarding of gear…1 January, 2010 by Michael Thorne
Background Calcium ion is tightly regulated in body fluids and for euryhaline fish, which are exposed to rapid changes in environmental [Ca2+], homeostasis is especially challenging. The gill is the…1 January, 2010 by Eric Wolff
Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective…1 January, 2010 by Martin Collins
The ichthyofauna of ocean margin regions is characterised by a succession of different species occurring at different depths. This study was aimed at determining whether the resultant pattern of species…1 January, 2010 by Richard Phillips
Marine environments experience seasonal variation in physical and biological parameters, with consequent changes in predator distributions. During the breeding period, proximity to suitable feeding sites is essential for central place…1 January, 2010 by Rowan Whittle
Adamussium jonkersi sp. nov. is described from the Late Oligocene Destruction Bay Formation, Wrona Buttress area, King George Island (South Shetlands), West Antarctica. The unit, characterized by volcanic sandstone, is…Read more on A new fossil Adamussium (Bivalvia: Pectinidae) from Antarctica
1 January, 2010 by Norman Ratcliffe
The introduction of mammal predators to islands often results in rapid declines in the number and range of seabirds. On Ascension Island the introduction of cats in 1815 resulted in…1 January, 2010 by Richard Phillips
Pelagic seabirds are central place foragers during breeding and variation in foraging trip duration and range reflect differences in diet and chick provisioning, through the exploitation of divergent habitats of…1 January, 2010 by Eugene Murphy, Jonathan Watkins, Peter Enderlein, Philip Trathan, Sophie Fielding
The South Georgia region supports a large biomass of krill that is subject to high inter-annual variability. The apparent lack of a locally self-maintaining krill population at South Georgia means…1 January, 2010 by Peter Ward
Plankton are the main food source in the majority of marine ecosystems and have a crucial role in climate change through primary production and the export of carbon to the…Read more on A global continuous plankton recorder programme
1 January, 2010 by Claus-Dieter Hillenbrand
An increase in whole ocean alkalinity during glacial periods could account, in part, for the drawdown of atmospheric CO2 into the ocean. Such an increase was inevitable due to the…Read more on Evidence for elevated alkalinity in the glacial Southern Ocean
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…