Showing 11205 items
1 January, 2006 by Jaume Forcada
Winter dispersal in leopard seals is poorly understood because of its low density in most of its range. By combining photo-identification and tagging data from Bird Island, South Georgia, in…1 January, 2006 by Andrew Clarke
We suggest that the epibenthic communities of passive suspension feeders that dominate some high-Antarctic seafloors present unique archaic features that are the result of long isolation, together with the effects…1 January, 2006 by Mark Preston, Philip Trathan
The use of automated systems to record the identity of individual penguins and their movements in and out of a colony can provide an effective means of studying penguin biology…1 January, 2006 by Hilmar Gudmundsson
Most of the ice lost from the Antarctic ice sheet passes through a few fast-flowing and highly dynamic ice streams(1). Quantifying temporal variations in flow in these ice streams, and…Read more on Fortnightly variations in the flow velocity of Rutford Ice Stream, West Antarctica
1 January, 2006
We present a multiple regression analysis of time series of the leading modes of variability in high latitudes, the Northern and Southern Annular Modes (NAM and SAM). The potential forcing…1 January, 2006
Increasing evidence exists that the strong warming of the West Antarctic Peninsula (WAP) region since the 1950s is related to reduced sea ice that is likely to be due to…1 January, 2006
The contribution of the atmospheric circulation to a record minimum extent of open water in the polar Ross Sea (RS) region in the 2003 austral summer is examined. Two major…1 January, 2006 by Roger Worland
1. Cold tolerance is a fundamental adaptation of insects to high latitudes. Flexibility in the cold hardening process, in turn, provides a useful indicator of the extent to which polar…1 January, 2006 by Roger Worland, Peter Convey
Modality in the supercooling points of cold tolerant but freezing intolerant terrestrial arthropods has proved a pragmatically reliable means of distinguishing between summer and winter cold hardiness in such species.…Read more on Ecologically realistic modalities in arthropod supercooling point distributions
1 January, 2006
We present data from the European Space Agency's Airborne SAR/Interferometric Radar Altimeter System (ASIRAS), flown during the CryoVex 2004 field calibration/validation campaign, and new, high-resolution depth profiles of snow density…Read more on ASIRAS airborne radar resolves internal annual layers in the dry-snow zone of Greenland
1 January, 2006
We have made side-by-side measurements in several boreholes at Summit, Greenland, using borehole optical stratigraphy (BOS) and neutron-scattering density logging techniques. The BOS logs show strong positive correlation at shallow…1 January, 2006
In this study we employ the TRIFFID (Top-down Representation of Interactive Flora and Foliage Including Dynamics) Dynamic Global Vegetation Model (DGVM) and the Hadley Centre Atmospheric General Circulation Model version…1 January, 2006 by Robert Larter
A Fossil Mounded Sedimentary Body (MB) has been identified in the sedimentary record on the central continental rise west of Adelaide Island, on the Antarctic Peninsula Pacific margin. The growth…1 January, 2006
An imaging Doppler interferometer (IDI) at Halley, Antarctica (76°S, 26°W) has been used to record near continuous mean winds in the mesosphere/lower thermosphere since December 1996. Monthly mean winds are…Read more on Mean winds and tides in the mesosphere and lower thermosphere above Halley, Antarctica
1 January, 2006 by Eugene Murphy, Philip Trathan, Simeon Hill
The ecosystem approach to fisheries recognises the interdependence between harvested species and other ecosystem components. It aims to account for the propagation of the effects of harvesting through the food-web.…Read more on Modelling Southern Ocean ecosystems: krill, the food-web, and the impacts of harvesting
1 January, 2006 by Claus-Dieter Hillenbrand
Oceanic stratification represents an effective mechanism to reduce vertical mixing of the water column, thereby locking up carbon dioxide (CO2) in the deep sea and preventing air–sea exchange of CO2.…Read more on Polar stratification: A critical view from the Southern Ocean
1 January, 2006 by Richard Hindmarsh, Richard Hindmarsh
Membrane stresses act along thin bodies which are relatively well lubricated on both surfaces. They operate in ice sheets because the bottom is either sliding, or is much less viscous…1 January, 2006 by Hilmar Gudmundsson, Richard Hindmarsh, Richard Hindmarsh
Internal isochronic layers in ice sheets sensed by radar show two characteristic relationships to the basal topography: Either they override it, with layers above the crests of rises lying essentially…1 January, 2006 by Richard Hindmarsh, Richard Hindmarsh
Calculations of thermomechanically coupled ice sheet evolution using the shallow ice approximation exhibit the development of fingering instabilities in velocity, temperature, and thickness, which have been argued to resemble and…Read more on Stress gradient damping of thermoviscous ice flow instabilities
1 January, 2006
Using a global data set on egg hatch times in zooplanktonic and nektonic ectotherms from marine waters, the combined effects of body size, temperature and life-history attributes on development times…1 January, 2006 by Dominic Hodgson
We reconstruct terrestrial and freshwater environments of the last two Quaternary interglacials in coastal east Antarctica by examining multi-proxy evidence in a lake sediment core. The record, from Progress Lake…1 January, 2006 by Dominic Hodgson, James Smith, Stephen Roberts
Temperatures on the Antarctic Peninsula are increasing at a rate of 3.4°C per century, more than five times the global mean. At the same time, the region's ice shelves have…Read more on Examining Holocene stability of Antarctic Peninsula ice shelves
1 January, 2006 by Dominic Hodgson
Research in East Antarctica has shown several recent environmental changes that may be linked to human impacts on climate. In order to detect the influence and context of these changes…Read more on Recent rapid salinity rise in three East Antarctic lakes
1 January, 2006 by Jaume Forcada
Published studies of wild vertebrate populations have almost universally reported positive associations between genetic variation measured at microsatellite loci and fitness, creating the impression of ubiquity both in terms of…1 January, 2006 by Philip Trathan
Genetic tagging, the identification of individuals using their genotypes, provides a powerful tool for studying animals that are difficult to observe or identify using conventional techniques. However, despite being widely…1 January, 2006 by Kevin Newsham, Peter Convey
Antarctic terrestrial ecosystems are noted for their relative simplicity and limited trophic structure. In this context, knowledge of biotic interactions in structuring terrestrial soil communities would seem beneficial from a…Read more on Biotic interactions in Antarctic terrestrial ecosystems: are they a factor?
1 January, 2006 by Paul Holland
A model of the dynamics and thermodynamics of a plume of meltwater at the base of an ice shelf is presented. Such ice shelf water plumes may become supercooled and…Read more on The effects of rotation and ice shelf topography on frazil-laden ice shelf water plumes
1 January, 2006 by David Vaughan, Hugh Corr
Airborne radar sounding over the Thwaites Glacier (TG) catchment and its surroundings provides the first comprehensive view of subglacial topography in this dynamic part of the West Antarctic Ice Sheet…1 January, 2006 by Kevin Hughes
This study shows that increased UV-B arising from stratospheric ozone depletion over Antarctica reduced cell viability and the maximum quantum yield of photochemistry (F v/F m) in a unicellular terrestrial…1 January, 2006 by Kevin Hughes, Peter Convey
In the Arctic, seasonal ozone depletion is resulting in periods of enhanced UV-B radiation at ground level while regional climate change is associated with increasing temperatures. These changes are likely…1 January, 2006 by David Barnes
Fatty acid analyses are emerging as a powerful technique to probe trophic interactions between organisms. In this paper, the application of both this procedure and gonad index (GI) determination on…1 January, 2006 by Kevin Hughes
Fuel oil has been extensively relied upon as an energy source since the earliest discovery and exploration of Antarctica. During this time oil spills have occurred, particularly around established research…Read more on Oil pollution in the Antarctic terrestrial environment
1 January, 2006
Dating Jurassic terrestrial floras in the Antarctic Peninsula has proved problematic and controversial. Here U–Pb series dating on detrital zircons from a conglomerate interbedded with fossil plant material provide a…1 January, 2006
Recent detailed mapping, section logging and an improved understanding of the geological evolution of the Antarctic Peninsula provide a robust framework for an improved lithostratigraphic subdivision of the Latady Basin,…1 January, 2006 by Teal Riley
The Jurassic Mount Poster Formation of eastern Ellsworth Land, southern Antarctic Peninsula, comprises silicic ignimbrites related to intracontinental rifting of Gondwana. The identification of less voluminous basaltic and sedimentary facies…1 January, 2006 by Nigel Meredith, Richard Horne
We present an analysis of the electron phase space density in the Earth's outer radiation belt during three magnetically disturbed periods to determine the likely roles of inward radial diffusion…Read more on Phase space density analysis of the outer radiation belt energetic electron dynamics
1 January, 2006
Geomagnetic data from five northern hemisphere observatories at latitudes ranging from 22 degrees N to 67 degrees N have been used to investigate long-term trends in planetary wave activity in…1 January, 2006 by Adrian Jenkins, Hugh Corr, Keith Nicholls
Basal melting of Antarctica’s floating ice shelves accounts for between 15 and 35% of the total mass loss from the ice sheet and helps to precondition the shelf waters for…1 January, 2006 by Adrian Jenkins, Hugh Corr, Keith Nicholls
Precise measurements of basal melting have been made at a series of 14 sites lying within a few kilometres of the grounding line of the Ronne Ice Shelf, Antarctica, where…1 January, 2006 by Adrian Jenkins, Keith Nicholls
Within the cavity beneath Filchner-Ronne Ice Shelf (FRIS), High Salinity Shelf Water (HSSW) is transformed into Ice Shelf Water (ISW) by a combination of melting and freezing at the ice…1 January, 2006 by Anna Jones, Eric Wolff, John Turner, Steve Colwell
Since March 2003, measurements of surface ozone have been made at the British Antarctic Survey Clean Air Sector Laboratory (CASLab) at Halley station in coastal Antarctica. Detailed measurements of boundary…1 January, 2006 by Martin Collins
We deployed 2 porpoise (Phocoena phocoena) carcasses at bathyal depth (2555 to 2710 m) in the Porcupine Seabight, NE Atlantic for periods of 1 wk and 6 mo respectively. Consumption…Read more on Consumption of large bathyal food fall, a six month study in the NE Atlantic
1 January, 2006 by John King
The Antarctic research stations of Dome C and Halley lie at similar latitudes (∼75°S) and are thus subject to similar diurnal variation of solar radiation at the top of the…1 January, 2006 by David Barnes
In order to study taxon richness, biodiversity and abundance patterns in the North Atlantic from temperate latitudes through Arctic to high Arctic latitudes, we recorded the faunas (at ELWS level)…1 January, 2006 by Thomas Lachlan-Cope
Tropical Pacific–high southern latitude teleconnections are shown to be caused by Rossby wave dynamics and are sensitive to the exact pattern of sea surface temperature (SST) anomalies forcing anomalous ascent.…1 January, 2006 by Mai Mai Lam, Michael Pinnock
The temporal and spatial variability of nightside magnetic reconnection is described using two-dimensional ionospheric measurements during the growth phase and early expansion phase of a single substorm. Two techniques (A…1 January, 2006 by Philip Trathan
Sea surface temperature (SST) time-series from the southwest Atlantic and the El Niño 4 region in the western Pacific were compared to an index of annual calving success of the…Read more on Global climate drives southern right whale (Eubalaena australis) population dynamics
1 January, 2006 by Katrin Linse
Bouvet Island is one of the most isolated islands in the Southern Ocean and its marine benthic fauna has rarely been investigated and so is poorly known. This study adds…1 January, 2006 by David Barnes, Katrin Linse, Peter Enderlein
Much has been made of body-size variability with latitude, and extreme body sizes in polar waters, but body size has never been investigated along a latitudinal gradient within polar waters.…Read more on Body size and growth of benthic invertebrates along an Antarctic latitudinal gradient
1 January, 2006 by Andrew Clarke, David Barnes, Huw Griffiths, Katrin Linse
For many decades molluscan data have been critical to the establishment of the concept of a global-scale increase in species richness from the poles to the equator. Low polar diversity…Read more on Biodiversity and biogeography of Antarctic and sub-Antarctic mollusca
1 January, 2006 by Eric Wolff
We determine the physicochemical habitat for microorganisms in subsurface terrestrial ice by quantitatively constraining the partitioning of bacteria and fluorescent beads (1–10 m) between the solid ice crystals and the…1 January, 2006 by Eric Wolff
Sea-salt aerosols represent a significant fraction of the aerosol optical depth over the oceans, and thus their response to changes in climate represents an important potential feedback on climate. Model…1 January, 2006 by Keith Makinson
The ice front region of Ronne Ice Shelf lies near the critical latitude of the semidiurnal M2 tide, the principal tidal constituent in the southern Weddell Sea. Here the Coriolis…1 January, 2006 by Keith Makinson
Ice streams are major drainage routes, through which much of the ice in Antarctica flows from the continent. They flow at speeds of up to two orders of magnitude greater…Read more on Future hot water drilling on Rutford Ice Stream 2004/05
1 January, 2006 by Keith Makinson
High Salinity Shelf Water (HSSW) flowing into the cavity beneath Filchner-Ronne Ice Shelf (FRIS) occupies the lower portion of the water column. Tidal mixing is likely to be a primary…Read more on Tidal vertical mixing beneath Filchner-Ronne Ice Shelf
1 January, 2006 by Gareth Marshall
We examine the impact that changes in the winter Southern Hemisphere (SH) meridional sea surface temperature (SST) gradient have on the sign and strength of the SH Annular Mode (SAM).…1 January, 2006 by Gareth Marshall, John King
Since the mid-1960s, rapid regional summer warming has occurred on the east coast of the northern Antarctic Peninsula, with near-surface temperatures increasing by more than 2°C. This warming has contributed…1 January, 2006 by Richard Hindmarsh, Richard Hindmarsh
Radar-detected internal layering contained in some ice divides shows upwarped arches termed Raymond bumps. The distribution of their amplitude with height can date the onset of divide flow, reflecting changes…1 January, 2006 by Peter Convey, Rolf Maslen
Nematode worms are one of the most important soil faunal groups in Antarctica. However, relatively little is known about their wider distribution, biogeography and history in the region, and taxonomic…1 January, 2006
A rapid increase in the variety, quality, and quantity of observations in polar regions is leading to a significant improvement in the understanding of sea ice dynamic and thermodynamic processes…1 January, 2006 by Mark Clilverd, Michael Rose
Plasmaspheric ducts may execute Doppler oscillations driven by propagating ultra-low frequency (ULF) waves. We examined about 100 such events recorded over 1 year under magnetically quiet conditions at L =…1 January, 2006 by Mark Clilverd, Nigel Meredith, Richard Horne
Plasmaspheric hiss is an electromagnetic wave emission responsible for electron loss from the radiation belts, particularly in the slot region (2 < L < 3). There are two leading theories…1 January, 2006 by Nigel Meredith, Richard Horne, Sarah Glauert
Following enhanced magnetic activity the fluxes of energetic electrons in the Earth's outer radiation belt gradually decay to quiet-time levels. We use CRRES observations to estimate the energetic electron loss…Read more on Energetic outer zone electron loss timescales during low geomagnetic activity
1 January, 2006
We explore methods of dating a 101 m ice core from a bare ice ablation area in the Yamato Mountains, Dronning Maud Land, East Antarctica. There are two unknowns, the…1 January, 2006 by Mark Belchier, Simon Morley
We present the first fecundity and egg size data for three species of lithodid crab from Antarctic waters south of the Polar Front, caught in the fisheries operating around the…Read more on Reproductive strategies of sub-Antarctic lithodid crabs vary with habitat depth
1 January, 2006 by David Barnes
In July 2003 Kirsty Brown, a marine biologist at Rothera Research Station (West Antarctic Peninsula), was attacked and drowned by a leopard seal (Hydrurga leptonyx). As a direct consequence, a…1 January, 2006
A function that approximates atmospheric tidal behavior in the polar regions is described. This function is fitted to multistation radar measurements of wind in the mesosphere and lower thermosphere with…Read more on A climatology of tides in the Antarctic mesosphere and lower thermosphere
1 January, 2006 by Kevin Newsham, Rolf Maslen, Sandra McInnes, Sandra McInnes
A sample of the liverwort Cephaloziella varians was collected on 1 January 1999 at Rothera Point on the Wright Peninsula, Adelaide Island, western Antarctic Peninsula and was partially dried and…Read more on Survival of antarctic soil metazoans at −80°C for six years
1 January, 2006 by Keith Nicholls
As a result of their importance in the production of Antarctic Bottom Water, processes over the Antarctic continental shelf have a strong impact on the global ocean. Some of the…Read more on Interannual variability beneath Filchner-Ronne Ice Shelf, Antarctica
1 January, 2006
All-sky CCD observations of short-period mesospheric gravity waves have been made from Halley Station, Antarctica (76°S, 27°W). On 27 May, 2001, an unusual wave event exhibiting several features characteristic of…Read more on An unusual mesospheric bore event observed at high latitudes over Antarctica
1 January, 2006 by Michael Pinnock
Auroral westward flow channels (AWFCs) are intense, narrow channels of westward drift overlapping the equatorward edge of the auroral oval in the pre-magnetic midnight sector. They are a close relative…Read more on On the occurrence of auroral westward flow channels and substorm phase
1 January, 2006 by Richard Hindmarsh, Richard Hindmarsh
The effect of spatial variations in ice thickness, accumulation rate and lateral flow divergence on radar-detected isochrone geometry in ice sheets is computed using an analytical method, under assumptions of…1 January, 2006 by Andrew Clarke, Lloyd Peck
The Antarctic gastropods Marseniopsis mollis (Smith, 1902) and Torellia mirabilis (Smith, 1907) lay eggs in the late austral summer and autumn; these hatch the following late winter and early summer.…1 January, 2006 by David Barnes, Lloyd Peck, Peter Convey
Knowledge of Antarctic biotas and environments has increased dramatically in recent years. There has also been a rapid increase in the use of novel technologies. Despite this, some fundamental aspects…1 January, 2006 by Andy Smith
Laterally continuous subglacial sediments are a necessary component for ice streaming in the modern onset regions of the ice streams draining the Siple Coast of West Antarctica on the basis…1 January, 2006 by Mervyn Freeman, Richard Horne
Collisionless magnetic reconnection requires the violation of ideal MHD by various kinetic-scale effects whose relative importance is uncertain. Recent research has highlighted the potential importance of wave-particle interactions by showing…Read more on Anomalous resistivity and the non-linear evolution of the ion-acoustic instability
1 January, 2006 by Mervyn Freeman
We present an analysis of the electric and magnetic wave spectra on kinetic scales during several crossings of a reconnecting current sheet. The spectra were measured from 1 Hz or…1 January, 2006 by Richard Phillips, Vsevolod Afanasyev
The white-chinned petrel Procellaria aequinoctialis is a medium-sized procellariiform with a circumpolar subAntarctic breeding distribution. Feeding during both day and night, and often competing aggressively for bait, offal and discards,…1 January, 2006 by Richard Phillips
Although a variety of techniques (including water-offloading, and spontaneous and induced regurgitation) are used routinely to obtain fresh stomach samples from seabirds, there have been few studies of their efficacy…Read more on Efficacy and effects of diet sampling of albatross chicks
1 January, 2006 by Philip Trathan, Richard Phillips
Long-term studies at Bird Island, South Georgia, show that numbers of wandering, black-browed and grey-headed albatrosses have been decreasing since the late 1970s. To determine the status of the total…1 January, 2006
Naturally occurring microbial communities are complex, with autotrophs and heterotrophs often similarly sized and impossible to separate by conventional size fractionation approaches. However, if it was possible to identify specific…1 January, 2006 by Andrew Clarke
Through functional analyses, integrative physiology is able to link molecular biology with ecology as well as evolutionary biology and is thereby expected to provide access to the evolution of molecular,…Read more on Trade-offs in thermal adaptation: the need for a molecular to ecological integration
1 January, 2006 by Lloyd Peck
Understanding thermal limits and the ability of species to cope with changing temperatures is crucial for a cause and effect understanding of climate effects on organisms and ecosystems. Data available…1 January, 2006 by Martin Collins
The oceanic abyss (depths greater than 3000 m), one of the largest environments on the planet, is characterized by absence of solar light, high pressures and remoteness from surface food…Read more on The absence of sharks from abyssal regions of the world’s oceans
1 January, 2006
A detailed record of late Pleistocene deglaciation followed by mid-Holocene ice shelf breakup and late Holocene re-growth is contained in continental shelf sediments in the northern Larsen area, northeast Antarctic…1 January, 2006 by Peter Convey
The molecular weight distributions and hydrolysable neutral sugar composition of dissolved organic carbon (DOC) was investigated in four maritime Antarctic lakes on Signy Island of different trophic status; Heywood Lake…1 January, 2006
British Antarctic Survey director Chris Rapley (above) first conceived the idea of an International Polar Year back in early 2003. It has now grown into the world’s largest coordinated science…1 January, 2006 by Iain Staniland
The spatial and temporal variability in the fish component of the diet of Antarctic fur seals (Arctocephalus gazella (Peters, 1875)) in the Atlantic sector of the Southern Ocean was examined…1 January, 2006
Observations from a novel autonomous Doppler sodar wind profiling system are described and analysed. These include the first continuous wintertime soundings of katabatic winds over Antarctica - a continent with…Read more on Profiles of katabatic flows in summer and winter over Coats Land, Antarctica
1 January, 2006 by Philip Leat, Teal Riley
A suite of mafic dykes from the Underberg region of southern KwaZulu-Natal (South Africa) were intruded at 178 Ma, coincident in age with the major Okavango Dyke Swarm of Botswana,…Read more on Overlap of Karoo and Ferrar magma types in KwaZulu-Natal, South Africa