Showing 11205 items
1 January, 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…1 January, 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.…1 January, 2009
This study assesses the relation between the year-to-year variability of the semidiurnal tides (SDT) observed at high latitudes of both hemispheres and the global stratospheric stationary planetary wave (SPW) with…Read more on Asymmetry in the interhemispheric planetary wave-tide link between the two hemispheres
1 January, 2009
Antarctic ecosystems are fascinating in their limited trophic complexity, with decomposition and nutrient cycling functions being dominated by microbial activities. Not only are Antarctic habitats exposed to extreme environmental conditions,…Read more on Environmental microarray analyses of Antarctic soil microbial communities
1 January, 2009 by Michael Pinnock
Ground-based dual-frequency GPS observations can be used to create images of electron density. This is well established for the Arctic ionosphere; here one of the first results is presented for…Read more on Imaging of the Antarctic ionosphere: Experimental results
1 December, 2008 by Martin Collins
Understanding how environmental forcing has generated and maintained large-scale patterns of biodiversity is a key goal of evolutionary research and critical to predicting the impacts of global climate change. We…1 December, 2008 by Adrian Jenkins, Povl Abrahamsen, Keith Nicholls
Limitations of access have long restricted exploration and investigation of the cavities beneath ice shelves to a small number of drillholes. Studies of sea-ice underwater morphology are limited largely to…1 October, 2008 by Martin Collins, Mark Belchier
Recruitment variability in juvenile Patagonian toothfish (Dissostichus eleginoides), a commercially important, deepwater nototheniid fish, was examined at the sub-Antarctic island of South Georgia, South Atlantic. Data from 13 demersal trawl…1 September, 2008 by Adrian Jenkins
Results are presented from an isopycnic coordinate model of ocean circulation in the Amundsen Sea, focusing on the delivery of Circumpolar Deep Water (CDW) to the inner continental shelf around…1 August, 2008 by Richard Phillips
Parasitism can be a major constraint on host condition and an important selective force. Theoretical and empirical evidence shows that maternal condition affects relative investment in sons and daughters; however,…Read more on Parasite treatment affects maternal investment in sons
15 July, 2008 by Alexander Tate, Dominic Hodgson, Peter Fretwell, Robert Larter
A grid derived from a new compilation of marine echo-sounding data sets has allowed us to visualize and map the geomorphology of the entire continental shelf around South Georgia at…1 June, 2008 by Claire Waluda, Geraint Tarling, Martin Collins, Nadine Johnston, Peter Enderlein
The mesopelagic fish community of the northern Scotia Sea was investigated during the austral autumn using multi-frequency acoustics, opening and closing nets and pelagic trawls fished from the surface to…Read more on Patterns in the distribution of myctophid fish in the northern Scotia Sea ecosystem
1 June, 2008 by Martin Collins
Recent trawling in the Southern Ocean has yielded individuals of a number of species of the deep sea octopod genus Thaumeledone. This paper provides the first molecular study of the…1 June, 2008
We examine ship-based observations of atmospheric O-2 and CO2 in the southern Pacific Ocean made during two voyages: in February 2003 and in April 2004. We found, for the Austral…1 May, 2008
The Tyrone Central Inlier is a metamorphic terrane of uncertain affinity situated outboard of the main Dalradian outcrop (south of the Fair Head–Clew Bay Line) and could represent sub-arc basement…1 April, 2008 by Andrew Orr, Gareth Marshall, John King
Summer near-surface temperatures over the northeast coast of the Antarctic Peninsula have increased by more than 2°C over the past 40 years, a temperature increase 3 times greater than that…1 April, 2008 by Martin Collins
The reproductive biology of two species of endemic Southern Ocean octopods was investigated around the sub-Antarctic islands of South Georgia and Shag Rocks. The females of both the species produce…1 April, 2008 by Adrian Jenkins
Oceanographic data are presented from the eastern Bellingshausen Sea, representing the first near-contemporaneous sampling of conditions near both the northern and southern ice fronts of George VI Ice Shelf. Circumpolar…Read more on Circulation and melting beneath George VI Ice Shelf, Antarctica
1 March, 2008
The longevity and extent of the oceanic southern margin of Gondwana have made it the subject of intense study for more than 70 years. It was one of the cradles…Read more on The West Gondwana margin : Proterozoic to Mesozoic
27 February, 2008 by Martin Collins, Mark Belchier
Pseudochaenichthys georgianus is a member of the unique Channichthyidae family of fishes, which lack haemoglobin. The distribution, length-frequency and summer diet are described from 14 bottom trawl surveys undertaken in…1 January, 2008
The MIST (magnetosphere, ionosphere and solar–terrestrial physics) group of the RAS has been reinvigorated with a more formal structure, including a council, and a more thematic approach to the regular…1 January, 2008 by Robert Mulvaney
Ice-core records of methanesulphonic acid (MSA) provide a potentially powerful tool for producing proxy records of sea ice, a critical but poorly understood component of the Earth's climate system. However,…Read more on The preservation of methanesulphonic acid in frozen ice-core samples
1 January, 2008 by Andy Smith, Keith Makinson, Keith Nicholls
High-resolution surface velocity measurements and passive seismic observations from Rutford Ice Stream, West Antarctica, 40 km upstream from the grounding line are presented. These measurements indicate a complex relationship between…1 January, 2008 by Mervyn Freeman
During the International Polar Year (IPY), one area of great interest is co-coordinated, multi-instrument probing of the ionosphere at high latitudes. This region is important not only for the applications…1 January, 2008
A morphological dataset based on 14 standard counts and indices was constructed for 68 specimens comprising 12 species of octopuses. This was used to construct distance matrices based on morphological…1 January, 2008 by Claire Allen
This paper provides new observations of volcanic features and hydrological characteristics in and around Southern Thule, the southernmost group of islands in the South Sandwich Islands, including the first high-resolution…Read more on Volcanic features and hydrological setting of Southern Thule, South Sandwich Islands
1 January, 2008 by Andrew Clarke
A long-standing mystery in genome evolution is why short tandem repeats vary so much in length and frequency. Here, we test the hypothesis that body temperature acts to influence the…Read more on Body temperature predicts maximum microsatellite length in mammals
1 January, 2008
Observations of the unique chemical environment over snow and ice in recent decades, particularly in the polar regions. have stimulated increasing interest in the boundary layer processes that mediate exchanges…1 January, 2008
It is widely believed that contemporary climate determines large-scale patterns of species richness. An alternative view proposes that species richness reflects biotic responses to historic climate changes. These competing "contemporary…Read more on Quaternary climate changes explain diversity among reptiles and amphibians
1 January, 2008 by Andrew Fleming, Eugene Murphy, Geraint Tarling, Peter Fretwell
Surveys of Euphausia superba often target localised shelves and ice edges where their growth rates and predation losses are atypically high. Emphasis on these areas has led to the current…Read more on Oceanic circumpolar habitats of Antarctic krill
1 January, 2008 by David Barnes
Shelf and slope cryptofauna were sampled at the most northerly shelf environments within the Southern Ocean, Shag Rocks. The area is remarkably rich, with seven phyla, 10 classes, 40 families…1 January, 2008 by David Barnes, Katrin Linse, Peter Enderlein
Studies of the recovery of the fauna following the 1967-70 eruptions at Deception Island, South Shetland Islands, have made it one of the best-studied marine sites of the Southern Ocean…Read more on Marine richness and gradients at Deception Island, Antarctica
1 January, 2008 by David Barnes, Lloyd Peck
Predictions of sensitivity to climate change of polar benthos vary markedly depending on whether physiological or ecological/biodiversity criteria are considered. A realistic consensus view must be achieved as soon as…Read more on Vulnerability of Antarctic shelf biodiversity to predicted regional warming
1 January, 2008
Planetary waves with periods between two and four days in the middle atmosphere over Antarctica are characterized using one year of data from the medium-frequency spaced antenna (MFSA) radars at…Read more on Short-period planetary waves in the Antarctic middle atmosphere
1 January, 2008
Interpretation of ice mass elevation changes observed by satellite altimetry demands quantification of the proportion of elevation change which is attributable to variations in firn densification. Detailed stratigraphic logging of…1 January, 2008
The Antarctic Treaty Summit, which will coincide with the fiftieth anniversary of the treaty's signing, will be held at the Smithsonian Institution's National Museum of Natural History, in Washington, D.…Read more on Antarctic Treaty summit to focus on global science policy lessons
1 January, 2008
For most seabirds, reproductive performance improves with age; in albatrosses this is thought not to be so (experience being acquired before starting breeding) but only one study (of chick growth…1 January, 2008 by Andrew Fleming, Adrian Fox
The Landsat Image Mosaic of Antarctica (LIMA) is the first true-color, high-spatial-resolution image of the seventh continent. It is constructed from nearly 1100 individually selected Landsat-7 ETM+ scenes. Each image…1 January, 2008
Seasonal variations in ice motion have been observed at several polythermal ice masses across the High Arctic, including the Greenland Ice Sheet. However, such variations in ice motion and their…1 January, 2008 by Dominic Hodgson
Aims: To exploit the cyanobacterial diversity of microbial mats growing in the benthic environment of Antarctic lakes for the discovery of novel antibiotic and antitumour activities. Methods and results: In…Read more on Cyanobacteria from benthic mats of Antarctic lakes as a source of new bioactivities
1 January, 2008 by Gareth Chisham, Mervyn Freeman
A statistical comparison of the latitude of the open/closed magnetic field line boundary (OCB) as estimated from the three far ultraviolet (FUV) detectors onboard the IMAGE spacecraft (the Wideband Imaging…1 January, 2008 by Michael Meredith, Sally Thorpe
CTD-Satellite Relay Data Loggers (CTD-SRDLs), each recording conductivity, temperature and pressure, were attached to Southern elephant seals (Mirounga leonina) on the island of South Georgia. During the animals’ migration the…1 January, 2008 by Michael Meredith, Sally Thorpe
We describe large-scale features of the Antarctic Circumpolar Current (ACC) in the Atlantic part of the Southern Ocean by merging Argo data and data obtained by novel animal-borne CTD sensors.…1 January, 2008
In 2005, Candida nivariensis, a yeast species genetically related to Candida glabrata, was described following its isolation from three patients in a single Spanish hospital. Between 2005 and 2006, 16…1 January, 2008 by Nigel Meredith
Plasmaspheric hiss1 is a type of electromagnetic wave found ubiquitously in the dense plasma region that encircles the Earth, known as the plasmasphere2. This important wave is known to remove3,…Read more on The unexpected origin of plasmaspheric hiss from discrete chorus emissions
1 January, 2008 by John Turner, Thomas Bracegirdle
Here we present a new assessment of Antarctic climate change over the 21st century based on data from the models that were developed as part of the Intergovernmental Panel on…Read more on Antarctic climate change over the twenty first century
1 January, 2008 by Roger Worland
A fungal pathogen provisionally identified as Neozygites cf. acaridis has recently been isolated from the Antarctic oribatid mite Alaskozetes antarcticus. The identification of the fungus is discussed with reference to…1 January, 2008 by Kevin Hughes
The zygomycete fungus Pirella circinans was isolated from cadavers of the beetle Hydromedion sparsutum from diverse sites on the sub-Antarctic Bird Island and was found to be the dominant or…1 January, 2008 by Kevin Newsham
The pathogenicity of an isolate of a Pythium species from Signy Island in the South Orkney Islands was tested against the Antarctic hairgrass Deschampsia antarctica. The isolate was found to…1 January, 2008
The hypothesis that ITS structural features can be used to define fungal groups, where sequence analysis is unsatisfactory, was examined in plant and animal pathogenic fungi. Structural models of ITS1…1 January, 2008
Twenty-six isolates of Colletotrichum kahawae, the causal agent of coffee berry disease, from coffee in Africa, and 25 isolates, mostly of Colletotrichum gloeosporioides, from coffee and other tropical perennial crops,…1 January, 2008
The taxonomy and nomenclature of the fungus commonly referred to as Stropharia aurantiaca was investigated. Molecular analysis of the ribosomal RNA large subunit gene confirmed the exclusion of the species…1 January, 2008
A reference checklist has been compiled giving the names of all species of non-lichenized fungi described by collection, observation or culture from the general Antarctic region since records were first…1 January, 2008
We determined growth rates of six coccolithophorid strains (five species) as a function of temperature. We grew four strains (three species: Emiliania huxleyi, Gephyrocapsa oceanica, and two strains of Calcidiscus…Read more on Growth rates of six coccolithophorid strains as a function of temperature.
1 January, 2008
Geological analysis of 5-10-m-long sediment cores in the context of the anthropologically derived materials within them has allowed us to identify ancient landscape features in the Theban area around Luxor,…1 January, 2008
1. The concept of integrated ecosystem conservation is widely supported as a framework to achieve sustainable management of biodiversity. However, paucity of data and limited methodological tools reduce its application…Read more on A species approach to marine ecosystem conservation
1 January, 2008 by Lloyd Peck
Active metabolic suppression in anticipation of winter conditions has been demonstrated in species of mammals, birds, reptiles and amphibians, but not fish. This is because the reduction in metabolic rate…Read more on Hibernation in an Antarctic fish: on ice for winter
1 January, 2008
The anamorphic species Colletotrichum gloeosporioides has never been adequately typified according to modern nomenclatural practice, resulting in uncertainty as to application of the named A lectotype specimen is therefore designated…Read more on The typification of Colletotrichum gloeosporioides
1 January, 2008 by Peter Convey
Background: Mitogenomics data, i.e. complete mitochondrial genome sequences, are popular molecular markers used for phylogenetic, phylogeographic and ecological studies in different animal lineages. Their comparative analysis has been used to…1 January, 2008 by Michael Meredith
Polar regions are particularly sensitive to climate change, with the potential for significant feedbacks between ocean circulation, sea ice, and the ocean carbon cycle. However, the difficulty in obtaining in…Read more on Southern Ocean frontal structure and sea ice formation rates revealed by elephant seals
1 January, 2008 by Gareth Chisham, Mai Mai Lam, Mervyn Freeman, Michael Pinnock
Magnetic reconnection is the most significant process that results in the transport of magnetised plasma into, and out of, the Earth's magnetosphere-ionosphere system. There is also compelling observational evidence that…1 January, 2008 by Gareth Chisham
Accurately mapping the location of ionospheric backscatter targets (density irregularities) identified by the Super Dual Auroral Radar Network (SuperDARN) HF radars can be a major problem, particularly at far ranges…1 January, 2008 by Melody Clark
Physiological adaptation to increased environmental temperatures has been studied experimentally in a number of fish species, with the up-regulation of several genes identified as being associated with the process, such…1 January, 2008 by Lloyd Peck, Melody Clark
Members of the HSP70 gene family comprising the constitutive (HSC70) and inducible (HSP70) genes, plus GRP78 (Glucose-regulated protein 78 kDa) were surveyed for expression levels via Q-PCR after both an…Read more on The HSP70 heat shock response in the Antarctic fish Harpagifer antarcticus.
1 January, 2008 by Lloyd Peck, Melody Clark
The success of any organism depends not only on niche adaptation but also the ability to survive environmental perturbation from homeostasis, a situation generically described as stress. Although species-specific mechanisms…Read more on Antarctic marine molluscs do have an HSP70 heat shock response
1 January, 2008 by Lloyd Peck, Melody Clark
Members of the HSP70 gene family comprising the inducible (HSP70) genes and GRP78 (glucose-regulated protein 78 kDa) were identified in an Antarctic sea star (Odontaster validus) and an Antarctic gammarid…Read more on Lack of an HSP70 heat shock response in two Antarctic marine invertebrates
1 January, 2008 by David Barnes, Lloyd Peck, Melody Clark, Paul Geissler
Heat shock proteins (HSPs) are a family of genes classically used to measure levels of organism stress. We have previously identified two HSP70 genes (HSP70A and HSP70B) in sub-tidal populations…Read more on Low heat shock thresholds in wild Antarctic intertidal limpets (Nacella concinna).
1 January, 2008 by Roger Worland, Melody Clark
Insects vary considerably in their ability to survive low temperatures. The tractability of these organisms to experimentation has lead to considerable physiology-based work investigating both the variability between species and…Read more on How insects survive the cold: molecular mechanisms – a review
1 January, 2008 by Andrew Clarke
Although biological work in the Southern Ocean extends back well over a century, studies in the past two decades have changed significantly our understanding of the ecology, diversity, biogeography and…Read more on Antarctic marine benthic diversity: patterns and processes
1 January, 2008 by Andrew Clarke
Elemental (C, N, P) composition was examined in 6 benthic marine invertebrates from Antarctica: 2 suspension feeders (the holothurian Heterocucumis steineni and the polychaete Thelepus cincinnatus), 1 epifaunal grazer (the…Read more on Ecological stoichiometry in six species of Antarctic marine benthos
1 January, 2008 by Andrew Clarke, Michael Meredith
We report data from the first 8 years of oceanographic monitoring in Ryder Bay, northern Marguerite Bay, Antarctica. These data form the oceanographic component of the Rothera Oceanographic and Biological…1 January, 2008 by Andrew Clarke
We examine variation associated with phylogeny in the scaling of body temperature in endotherms, using data from 596 species of mammal and 490 species of bird. Among higher groups of…Read more on Scaling of body temperature in mammals and birds
1 January, 2008 by Andrew Clarke
Antarctic krill (Euphausia superba) is a large euphausiid, widely distributed within the Southern Ocean [1], and a key species in the Antarctic food web [2]. The Discovery Investigations in the…Read more on Adult Antarctic krill feeding at abyssal depths
1 January, 2008 by Mark Clilverd, Neil Cobbett, Tracy Moffat-Griffin
Geosynchronous Los Alamos National Laboratory (LANL-97A) satellite particle data, riometer data, and radio wave data recorded at high geomagnetic latitudes in the region south of Australia and New Zealand are…1 January, 2008 by Mark Clilverd, Nigel Meredith
The principal loss mechanism for electrons from the inner radiation belt (1.2 < L < 2.0) and slot region (2.0 < L < 3.0) is atmospheric precipitation driven by several…Read more on Ground-based transmitter signals observed from space: Ducted or nonducted?
1 January, 2008
The reproductive performances of Grey-headed Albatrosses Diomedea chrysostoma with a previous record (≤5 years) of consistent success (≤70% chicks fledged from eggs laid—“top” birds) or failure (≤ 70% of attempts…1 January, 2008 by Martin Collins, Sophie Fielding
The distribution, total length (L-T) frequency and diet of Patagonotothen guntheri are described from 14 bottom trawl surveys conducted on the Shag Rocks and South Georgia shelves in the austral…1 January, 2008 by Dominic Hodgson, Claus-Dieter Hillenbrand, Peter Convey
Antarctica is a continent locked in ice, with almost 99.7% of current terrain covered by permanent ice and snow, and clear evidence that, as recently as the Last Glacial Maximum…Read more on Antarctic terrestrial life – challenging the history of the frozen continent?
1 January, 2008 by David Vaughan, Hugh Corr
Indirect evidence suggests that volcanic activity occurring beneath the West Antarctic ice sheet influences ice flow and sheet stability(1-3). However, only volcanoes that protrude through the ice sheet(4) and those…Read more on A recent volcanic eruption beneath the West Antarctic ice sheet
1 January, 2008 by Claus-Dieter Hillenbrand
Sediment drifts on the continental rise are located proximal to the western side of the Antarctic Peninsula and recorded changes in glacial volume and thermal regime over the last ca.…1 January, 2008 by Sandra McInnes, Sandra McInnes
Remains of tardigrades have rarely been reported to preserve in sediments, resulting in the absence of important ecological and biogeographic information that they could provide. However, a study of faunal…1 January, 2008 by Philip Leat, Teal Riley
The Mesozoic dyke swarms of Western Dronning Maud Land, Antarctica, form a minor intrusive component of the Karoo large igneous province. Five-hundred and sixty one dykes were recorded intruding Neoproterozoic…1 January, 2008
The influence of snow microstructure on thermal and radiative transfer in snow has not been thoroughly investigated as the tools necessary to efficiently measure microstructural geometry at millimeter resolution have…1 January, 2008 by Richard Horne
The arrival of high-speed solar wind streams (HSSs) at the Earth's magnetopause drives particle and wave phenomena that are distinct from the phenomena caused by other solar wind structures. Although…Read more on High-speed solar wind streams: a call for key research
1 January, 2008 by Fausto Ferraccioli, Tom Jordan
Recent satellite observations of Thwaites Glacier in the Amundsen Sea Embayment, West Antarctica, have shown that the glacier is changing rapidly. The causes of its dynamic behavior are uncertain but…Read more on First airborne gravity results over the Thwaites Glacier catchment, West Antarctica
1 January, 2008 by Claus-Dieter Hillenbrand, Robert Larter
A 330-km length of the little known continental shelf edge and slope of the Bellingshausen Sea, West Antarctica, is investigated using multibeam swath-bathymetric and sub-bottom profiler evidence. The shelf break…1 January, 2008
The new Horizontal Wind Model (HWM07) provides a statistical representation of the horizontal wind fields of the Earth's atmosphere from the ground to the exosphere (0-500 km). It represents over…Read more on An empirical model of the Earth’s horizontal wind fields: HWM07
1 January, 2008 by Richard Hindmarsh, Richard Hindmarsh
Ribbed moraines are large (up to 16 km long) ridges of sediment produced transverse to ice flow direction that formed widely beneath palaeo-ice sheets. Since ice sheet stability is sensitive…1 January, 2008 by Lloyd Peck
The world's oceans are slowly becoming more acidic. In the last 150 yr, the pH of the oceans has dropped by similar to 0.1 units, which is equivalent to a…1 January, 2008
1. Ecologists are obtaining ever-increasing amounts of data concerning animal movement. A movement strategy that has been concluded for a broad variety of animals is that of Lévy flights, which…1 January, 2008
The Antarctic Tropospheric Chemistry Investigation (ANTCI) was carried out from late November to December 2003 with both extended ground-based and tethered balloon studies at Amundsen Scott Station, South Pole. ANTCI…Read more on Antarctic Tropospheric Chemistry Investigation (ANTCI) 2003 overview
1 January, 2008 by David Vaughan
The East Antarctic Ice Sheet is the largest, highest, coldest, driest, and windiest ice sheet on Earth. Understanding of the surface mass balance (SMB) of Antarctica is necessary to determine…1 January, 2008
Life, as we know it, is constrained by various environmental parameters ( physical and chemical) and these vary both in space and time. Combinations of specific ranges for each of…1 January, 2008
We present a global empirical disturbance wind model (DWM07) that represents average geospace-storm-induced perturbations of upper thermospheric (200-600 km altitude) neutral winds. DWM07 depends on the following three parameters: magnetic…Read more on DWM07 global empirical model of upper thermospheric storm-induced disturbance winds
1 January, 2008 by Michael Rose, Richard Horne
Magnetic pulsations in the Pc1-Pc2 frequency range (0.1-5 Hz) are often observed on the ground and in the Earth's magnetosphere during the aftermath of geomagnetic storms. Numerous studies have suggested…