Showing 13455 items
1 January, 2007 by Geraint Tarling
Backscattering strength was estimated from 127 shipboard surveys with an acoustic Doppler current profiler (ADCP) made during Drake Passage transits from 1999 to 2004. The backscattering strength is used to…1 January, 2007 by Gareth Chisham, Mervyn Freeman, Michael Pinnock
The Super Dual Auroral Radar Network (SuperDARN) has been operating as an international co-operative organisation for over 10 years. The network has now grown so that the fields of view…1 January, 2007 by Peter Convey
Antarctica and its surrounding islands lie at one extreme of global variation in diversity. Typically, these regions are characterized as being species poor and having simple food webs. Here, we…Read more on Spatial and temporal variability across life’s hierarchies in the terrestrial Antarctic
1 January, 2007
Geomagnetic pulsation in the Pc3–4 bands have been studied at high Antarctic latitudes during the local summer. The statistical relation between the occurrence probability of Pc3 and Pc4 pulsations and…1 January, 2007 by Lloyd Peck, Melody Clark
We describe the levels of natural arm damage in the Antarctic brittle star Ophionotus victoriae and the rate of arm regeneration over the period of 1 yr, as measured in…Read more on Delayed arm regeneration in the Antarctic brittlestar Ophionotus victoriae
1 January, 2007 by Michael Thorne, Roger Worland, Melody Clark
Background Ice, snow and temperatures of -14°C are conditions which most animals would find difficult, if not impossible, to survive in. However this exactly describes the Arctic winter, and the…1 January, 2007 by Andrew Clarke, David Barnes, Huw Griffiths, Alistair Crame, Katrin Linse
The aim of this study was to use data for gastropod and bivalve molluscs to determine whether the fauna of the Southern Ocean is sufficiently well known to establish robust…1 January, 2007 by Andrew Clarke, Eugene Murphy, Nadine Johnston
Antarctica offers a unique natural laboratory for undertaking fundamental research on the relationship between climate, evolutionary processes and molecular adaptation. The fragmentation of Gondwana and the development of wide-scale glaciation…1 January, 2007 by Andrew Clarke, David Barnes, Eugene Murphy, John King, Lloyd Peck, Michael Meredith
The Antarctic Peninsula is experiencing one of the fastest rates of regional climate change on Earth, resulting in the collapse of ice shelves, the retreat of glaciers and the exposure…Read more on Climate change and the marine ecosystem of the western Antarctic Peninsula
1 January, 2007 by Mark Clilverd, Nigel Meredith, Richard Horne, Sarah Glauert
The tilt and offset of the Earth's magnetic field can significantly affect the longitudinal and seasonal distribution of electron density in the plasmasphere. Here we show that for the solar…1 January, 2007 by Mark Clilverd
Precipitation of relativistic electrons into the atmosphere has been suggested as the primary loss mechanism for radiation belt electrons during large geomagnetic storms. Here we investigate the geographical spread of…1 January, 2007 by David Pearce
We launched a cryptoendolithic habitat, made of a gneissic impactite inoculated with Chroococcidiopsis sp., into Earth orbit. After orbiting the Earth for 16 days, the rock entered the Earth's atmosphere…1 January, 2007
We report on a case of left main bronchus occlusion by an inhaled foreign body at a remote Antarctic scientific base during the austral winter. We present the dilemmas of…1 January, 2007 by Martin Collins, Mark Belchier
The distribution and diet of juvenile (1 January, 2007 by Thomas Bracegirdle
We assess 19 coupled models from the IPCC fourth assessment report archive from the simulation of the 20th century, based on the calculation of " skill scores.'' The models show…Read more on An Antarctic assessment of IPCC AR4 coupled models
1 January, 2007 by Peter Convey
The "sub-Antarctic" is a region of the planet characterised by small and extremely isolated island landmasses set in the vastness and harsh conditions of the Southern Ocean. Although there is…Read more on Influences on and origins of terrestrial biodiversity of the sub-Antarctic islands
1 January, 2007
We measured egg hatching tunes and stage specific naupliar development tinges of the key calanoid copepods Calanus helgolandicus and C. finmarchicus in response to temperature, food quantity and food type.…1 January, 2007 by Geraint Tarling
Antarctic krill Euphausia superba are key to most Antarctic ecosystems, particularly at South Georgia, where penguins and seals rely on them for their breeding success each summer. Changes in krill…Read more on Behaviour affects local-scale distributions of Antarctic krill around South Georgia
1 January, 2007 by Geraint Tarling, Philip Trathan
Question: How does the female macaroni penguin balance her own needs with those of her chick during breeding? Features of the model: We model the behaviour of female macaroni penguins…1 January, 2007
Glacial and post-glacial shelf sedimentation near the Larsen C and former Larsen B ice shelves is compared to records from ice shelves farther north, which underwent mid-Holocene retreat. A core…1 January, 2007
The Cooper Bay Dislocation Zone (CBDZ) represents a major NW-SE trending tectonic boundary within the island of South Georgia that juxtaposes components of a Middle Jurassic to mid-Cretaceous island-arc and…Read more on Main Andean sinistral shear along the Cooper Bay Dislocation Zone, South Georgia?
1 January, 2007
The growing world population increases the demand for water, energy, and land. This demand for natural resources impacts the transport of material and the supply of nutrients in the coastal…Read more on Potential impact of changes in river nutrient supply on global ocean biogeochemistry.
1 January, 2007 by Paul Rodhouse
There is now undisputed evidence that climate change and modifications of the Earth system occurs, at faster rates in the polar regions. Among the many consequences we will be facing,…1 January, 2007 by Sandra McInnes, Sandra McInnes
Low Lake, a freshwater pool at Cape Denison, Commonwealth Bay, Antarctica (67 degrees 20'40"S; 142 degrees 40'45 '' E) was sampled for protists and invertebrates. Forty species of protists were…Read more on Low life in Low Lake, a freshwater pool at Commonwealth Bay, Antarctica
1 January, 2007 by Vsevolod Afanasyev
In most long-lived animal species, juveniles survive less well than adults. A potential mechanism is inferior foraging skills but longitudinal studies that follow the development of juvenile foraging are needed…1 January, 2007
We present a detailed statistical analysis of acoustic emission time series from laboratory rock fracture obtained from different experiments on different materials including acoustic emission controlled triaxial fracture and punch-through…1 January, 2007 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
Summary Understanding the past glacial history of regions undergoing potential rapid deglaciation is essential in order to estimate the possible threat of sea level rise. Recently acquired data have given…1 January, 2007
Polar biology is on the threshold of a revolution based on new technologies (e.g. genomics, proteomics), which will greatly enhance our knowledge of polar ecosystems and their biodiversity. The broad…1 January, 2007 by Eugene Murphy, Mervyn Freeman, Richard Phillips, Vsevolod Afanasyev
The study of animal foraging behaviour is of practical ecological importance1, and exemplifies the wider scientific problem of optimizing search strategies2. Lévy flights are random walks, the step lengths of…Read more on Revisiting Lévy flight search patterns of wandering albatrosses, bumblebees and deer
1 January, 2007 by Katrin Linse
We examined deep-sea benthic data on polychaetes, isopods and bivalves from the Atlantic sector of the Southern Ocean. Samples were taken during the expeditions EASIZ II (1998), ANDEEP I and…1 January, 2007
The hydroxyl (OH) rotational temperature and band emission rate have been derived using year-round, ground-based measurements of the infrared OH nightglow from Sweden from 1991 to 2002. Recent work has…Read more on Seasonal variation in the correlation of airglow temperature and emission rate
1 January, 2007 by Geraint Tarling
A series of eight replicated acoustic surveys, four by day and four by night, was undertaken in Gullmarsfjord on the Swedish west coast during two 24-h periods on 8 and…1 January, 2007 by Fausto Ferraccioli, Philip Leat, Tom Jordan
The polar regions play an important role in Earth's geodynamic and climatic systems. Modern airborne geophysical surveys combine radio-echo sounding, aeromagnetic and aerogravity methods to explore the geology of these…1 January, 2007 by Carl Robinson, Fausto Ferraccioli, Hugh Corr, Tom Jordan
As we enter the IPY geological boundary conditions for the stability of the East Antarctic Ice Sheet (EAIS) remain largely unknown. During the 2005/06 field season a major new aerogeophysical…1 January, 2007 by David Vaughan, Fausto Ferraccioli, Hugh Corr, Tom Jordan
The West Antarctic Ice Sheet is currently undergoing rapid change in particular over the Amundsen Sea Embayment (ASE). Previous aerogeophysical investigations over the Ross Sea Embayment reveal that the underlying…1 January, 2007 by Dave Ingham
The British Antarctic Survey(BAS) is implementing a phased approach to completely redevelop Rothera Research Station, with the first phase currently work in progress. BAS operates five major research stations and…1 January, 2007 by Peter Ward, Sophie Fielding
Net sampling within the vicinity of the Crozet archipelago, in the Indian Ocean sector of the Southern Ocean, was conducted during late spring/summer (November 2004-January 2005) to describe the composition,…1 January, 2007 by Eric Wolff, Robert Mulvaney
Continuous sea salt and mineral dust aerosol records have been studied on the two EPICA (European Project for Ice Coring in Antarctica) deep ice cores. The joint use of these…1 January, 2007
[1] During the Northern Hemisphere summer, absorbed solar radiation melts snow and the upper surface of Arctic sea ice to generate meltwater that accumulates in ponds. The melt ponds reduce…Read more on A continuum model of melt pond evolution on Arctic sea ice
1 January, 2007 by Teal Riley
Five of six Rb-Sr muscovite mineral isochron ages from the Scotia Metamorphic Complex of the South Orkney Islands, West Antarctica, average 190 ± 4 Ma. The muscovite ages are interpreted…1 January, 2007
U-Pb detrital zircon geochronology from the upper Cambrian to Devonian part of the Ellsworth Mountains succession, Antarctica, yields dominant late Mesoproterozoic and late Neoproterozoic–Cambrian age populations that are onsistent with…1 January, 2007 by Elaina Ford
Recent advances in the performance of CCD detectors have enabled a high time resolution study of the high latitude upper thermosphere with Fabry-Perot Interferometers(FPIs) to be performed. 10-s integration times…1 January, 2007
The Neogene Meyer Desert Formation, Sirius Group, at Oliver Bluffs in the Transantarctic Mountains, contains a sequence of glacial deposits formed under a wet-based glacial regime. Within this sequence fluvial…1 January, 2007 by Andrew Clarke, Lloyd Peck
Growth rates in Antarctic ectotherms are generally considered to be low in comparison to temperate and tropical species. Food consumption plays a major role in determining animal growth rates, but…1 January, 2007
Growth is a fundamental process within all marine organisms. In soft tissues, growth is primarily achieved by the synthesis and retention of proteins as protein growth. The protein pool (all…Read more on Protein metabolism in marine animals: the underlying mechanism of growth
1 January, 2007 by Sandra McInnes, Sandra McInnes
The preservation of tardigrade eggs and exuviae in Antarctic lake sediments provided an opportunity to assess post-glacial colonisation and Holocene tardigrade dynamics on the southern continent. Tardigrade eggs were recovered…1 January, 2007 by Martin Collins
Natural bioluminescence (that not mechanically stimulated by human intervention) produced by organisms on the seafloor of the northeast Atlantic ocean between 970 and 4,800 m depth was examined using an…1 January, 2007
During the Late Miocene the Mediterranean experienced a period of extreme salinity fluctuations known as the Messinian Salinity Crisis (MSC). The causes of these high amplitude changes in salinity are…Read more on The Mediterranean hydrologic budget from a Late Miocene global climate simulation
1 January, 2007 by Robert Larter
The Amundsen Sea embayment of West Antarctica is in a prominent location for a series of tectonic and magmatic events from Paleozoic to Cenozoic times. Seismic, magnetic and gravity data…1 January, 2007 by Fausto Ferraccioli
More than 500,000 line-km of new airborne and shipborne data, recently acquired by the international community over East Antarctica and surrounding regions, significantly upgrade the Antarctic Digital Magnetic Anomaly Project…Read more on New magnetic anomaly map of East Antarctica and surrounding regions
1 January, 2007
Despite increasing interest in long-distance migration, the wintering areas, migration corridors, and population mix in winter quarters of most pelagic marine predators are unknown. Here, we present the first study…Read more on Trans-equatorial migration and mixing in the wintering areas of a pelagic seabird
1 January, 2007 by Claus-Dieter Hillenbrand, James Smith, Joanne Johnson, Robert Larter
The threat, in terms of sea level rise, posed by the potential rapid deglaciation of West Antarctica means there is an urgent need to know more about the speed and…1 January, 2007 by Lloyd Peck
This study reports the first multi-year observations on the reproductive patterns for an Antarctic predator/scavenger, Odontaster validus (Koehler 1912). Seastars were collected monthly from a shallow site (15–20 m depth)…1 January, 2007 by Anna Jones, Eric Wolff, Markus Frey
It has been shown that sunlit snow and ice plays an important role in processing atmospheric species. Photochemical production of a variety of chemicals has recently been reported to occur…Read more on An overview of snow photochemistry: evidence, mechanisms and impacts
1 January, 2007
INTRODUCTION: The potential advantage of including a psychological test battery in the selection process for service in the Antarctic was examined in 348 applicants for employment in Antarctica with the…Read more on Psychological selection of Antarctic personnel: the “SOAP” instrument
1 January, 2007
Foraging behaviour and energy expenditure were measured continuously throughout the chick-rearing period of free-ranging macaroni penguins Eudyptes chrysolophus. These data were integrated with values obtained from the literature on body…Read more on Feeding, fasting and foraging success during chick rearing in macaroni penguins
1 January, 2007 by Mark Clilverd
The equatorial plasma density and composition at L = 2.5 were studied during an extended disturbed interval using field line resonance measurements (yielding plasma mass density), naturally and artificially stimulated…1 January, 2007 by Hilmar Gudmundsson
[1] Surface speeds of Rutford Ice Stream, West Antarctica, are known to vary by around 10–20% (depending on location) with a fortnightly periodicity corresponding to a springneap tidal cycle. The…Read more on Tides and the flow of Rutford Ice Stream, West Antarctica
1 January, 2007 by Richard Phillips
Many seabirds nesting in areas bordering the North Sea have recently experienced large annual variation in breeding success, including reproductive failures in some cases. In contrast, the breeding success of…1 January, 2007 by Roger Worland, Peter Convey
The plasticity of an organism's phenotype may vary spatially and temporally, and across levels of physiological organisation. Given the adaptive value of plasticity in heterogeneous environments, it might be expected…1 January, 2007 by Roger Worland, Peter Convey
The effect of moulting on the cold hardiness of the oribatid mite Alaskozetes antarcticus (Michael) is investigated. Non moulting animals show clear seasonal patterns of cold hardiness with high supercooling…1 January, 2007 by Roger Worland, Peter Convey
Darwin was an early exponent of the importance of ‘occasional means of dispersal’ in accounting for the present-day distribution of plants and animals. This study examined the implications of capture…1 January, 2007 by Roger Worland, Peter Convey
Aerial dispersal has been frequently proposed as a potential mechanism by which polar terrestrial arthropods are transported to, and settle the ice free habitats of Antarctica, but to date there…1 January, 2007 by Adrian Jenkins
In March 2003 several autonomous underwater vehicle (AUV) missions were carried out under sea ice in the western Bellingshausen Sea. Data from the upward-looking acoustic Doppler current profiler (ADCP) on…1 January, 2007 by Victoria Peck
The Pliocene may have been characterized by permanent El Niño–like conditions. Initial modeling studies suggest that this may have contributed to Pliocene warmth. The termination of this state may have…Read more on A permanent El Niño–like state during the Pliocene?
1 January, 2007 by Anna Jones
Surface ozone records from ten polar research stations were investigated for the dependencies of ozone on radiative processes, snow-photochemisty, and synoptic and stratospheric transport. A total of 146 annual data…1 January, 2007
A Rayleigh-scatter lidar has been operated at the Atmospheric Lidar Observatory (ALO) on the Utah State University (USU) campus (41.7°N, 111.8°W) since August 1993. During the morning of 22 June…Read more on Observations of a noctilucent cloud above Logan, Utah (41.7oN, 111.8oW) in 1995
1 January, 2007
A cumulative total of over 5 years of data from an MF radar situated at Rothera (67°S, 68°W) on the Antarctic Peninsula have been used to derive climatologies of periodic…1 January, 2007 by Richard Hindmarsh, Richard Hindmarsh
The Pliocene (c. 5.3 - 1.8 Myr BP) was the last epoch of geological time in which global temperatures were generally higher than modern. It is important if we are…Read more on Characterizing ice sheets during the Pliocene: evidence from data and models