Showing 11205 items
1 January, 2007
The relationship between predator sizes and prey sizes is well documented for terrestrial but rarely for marine ecosystems. We show that wandering albatrosses, the biggest albatross species, feed on larger…Read more on Predator–prey interactions: why do larger albatrosses eat bigger squid?
1 January, 2007 by Andrew Wood, Paul Rodhouse
Assessing the consumption of prey by predators in the marine environment is key to fisheries assessment and management. Although environmental and ecological variations can affect the consumption of certain prey…1 January, 2007
The unusually harsh environmental conditions of terrestrial Antarctic habitats result in ecosystems with simplified trophic structures, where microbial processes are especially dominant as drivers of soil-borne nutrient cycling. We examined…1 January, 2007
Soil-borne microbial communities were examined via a functional gene microarray approach across a southern polar latitudinal gradient to gain insight into the environmental factors steering soil Nand C-cycling in terrestrial…1 January, 2007 by David Pearce, Kevin Newsham
Although soil-borne bacteria represent the world's greatest source of biological diversity, it is not well understood whether extreme environmental conditions, such as those found in Antarctic habitats, result in reduced…Read more on Patterns of bacterial diversity across a range of Antarctic terrestrial habitats
1 January, 2007 by Zhaomin Wang
The MPM-2, an Earth system model of intermediate complexity, is employed to study the climate system response to natural forcings during the pre-industrial era (1000-1800 AD), with a special focus…Read more on Simulation of the climatic effects of natural forcings during the pre-industrial era
1 January, 2007
We examine the geomagnetic field and space plasma disturbances developing simultaneously in the solar wind, in the inner and outer magnetosphere, and on the ground from 0730 to 2030 UT…1 December, 2006
Radar altimeters are one of the main tools for measuring elevation changes across the Antarctic and Greenland ice sheets and larger ice caps. A ground-based radar was deployed in autumn…1 December, 2006 by Andy Smith
Ten passive seismic recording stations were deployed in a 9 km by 6 km array on Rutford Ice Stream, West Antarctica, to detect microearthquakes from the ice stream bed. The…1 December, 2006
Physical, chemical and biological variables were quantified in 19 subantarctic lakes (South Georgia) as a prelude to comparing these pristine systems with temperate lakes and to improve the knowledge of…1 October, 2006 by Mark Clilverd
During the northern hemisphere winter of 2003–2004 significant levels of stratospheric odd nitrogen (NOX) were observed descending from the mesosphere. Here we study subionospheric radio wave propagation data from Ny…Read more on Ionospheric evidence of thermosphere-to-stratosphere descent of polar NOx
1 August, 2006 by Michael Meredith
Analysis of satellite altimeter data reveals anomalously high Eddy Kinetic Energy (EKE) in the Antarctic Circumpolar Current (ACC) during the period 2000–2002. Around 2–3 years earlier (1998), the circumpolar eastward…1 July, 2006
The Soufrière Hills volcano, Montserrat, West Indies, has undergone a series of dome growth and collapse events since the eruption began in 1995. Over 90% of the pyroclastic material produced…1 May, 2006 by Gabriele Stowasser, Martin Collins
Fatty acid and stable isotope analyses have previously been used to investigate foraging patterns of fish, birds, marine mammals and most recently cephalopod species. To evaluate the application of these…1 April, 2006 by Povl Abrahamsen, Keith Nicholls
The cavities beneath Antarctic ice shelves are among the least studied regions of the World Ocean, yet they are sites of globally important water mass transformations. Here we report results…Read more on Measurements beneath an Antarctic ice shelf using an autonomous underwater vehicle
1 April, 2006 by Mark Clilverd
Ozone observations from the GOMOS instrument together with a coupled ion and neutral chemistry model are used to study the effects of the January 2005 solar storms on the polar…Read more on Destruction of the tertiary ozone maximum during a solar proton event
1 March, 2006 by Eugene Murphy, Geraint Tarling, Jonathan Watkins
We used the instantaneous growth rate method to determine the effects of food, temperature, krill length, sex, and maturity stage on in situ summer growth of krill across the southwest…1 February, 2006
Rosemary Bank is a broadly domed and elongate seamount with a diameter of 70 km, occurring in water depths of between 300 and 2300 m, 120 km west of the…1 February, 2006 by Martin Collins
A long-synonymized species Benthoctopus normani (Massy 1907) (Cephalopoda: Octopodidae) is redescribed from material collected over 30 years by the National Oceanography Centre, Southampton and the National Museums of Scotland. It…1 February, 2006
Simulation modeling was used to reconstruct Black-browed Albatross (Diomedea melanophris) population trends. Close approximations to observed data were accomplished by annually varying survival rates, reproductive success, and probabilities of returning…1 January, 2006 by Gareth Chisham, Mervyn Freeman
We present a spatial structure function analysis of ionospheric velocity, measured by the Halley Super Dual Auroral Radar Network (SuperDARN) radar over five years. We show evidence for scale-free velocity…1 January, 2006 by Mervyn Freeman
Over recent years, substorm chorus events (SCEs) have been proposed as a useful indicator of substorm onset. The events are regularly seen in the data from the VELOX (VLF/ELF Logger…Read more on Association of substorm chorus events with drift echoes
1 January, 2006 by Povl Abrahamsen
From 1993 to 1996, three oceanographic moorings were deployed in the north-western Barents Sea, each with a current meter and an upward-looking sonar for measuring ice drafts. These yielded three…Read more on Ice draft and current measurements from the north-western Barents Sea, 1993-96
1 January, 2006
Understanding the relationship between soil biodiversity and ecosystem functioning is critical to predicting and monitoring the effects of ecosystem changes on important soil processes. However, most of Earth's soils are…Read more on Diversity and distribution of Victoria Land biota
1 January, 2006 by Peter Convey
The chironomid midges Belgica antarctica, Eretmoptera murphyi (subfamily Orthocladiinae) and Parochlus steinenii (subfamily Podonominae), are the only Diptera species currently found in Antarctica. The relationships between these species and a…1 January, 2006
The Greenland Ice Core Chronology 2005, GICC05, is extended back to 42 ka b2k (before 2000 AD), i.e. to the end of Greenland Stadial 11. The chronology is based on…Read more on The Greenland Ice Core Chronology 2005, 15–42ka. Part 1: constructing the time scale
1 January, 2006
Numerous factors influence the increased health risks of seamen. This study investigated sleep (by actigraphy) and the adaptation of the internal clock in watch-keeping crew compared to day workers, as…1 January, 2006 by Fausto Ferraccioli
Airborne geophysical surveys play a pivotal role in imaging subglacial geology and characterizing broad areas of the Antarctic liothsphere. Ground-based geophysics, coupled with airborne geophysics and geology, is essential to…Read more on Recent aeromagnetic and deep electromagnetic exploration projects in East Antarctica
1 January, 2006 by David Barnes, Katrin Linse
Bouvet (Bouvetøya) is a geologically young and very remote island just south of the Polar Front. Here we report samples taken during the RV “Polarstern" cruise ANTXXI/2 on 3 days…1 January, 2006 by Robert Arthern, Richard Hindmarsh, Richard Hindmarsh
The problem of forecasting the future behaviour of the Antarctic ice sheet is considered. We describe a method for optimizing this forecast by combining a model of ice sheet flow…1 January, 2006 by David Vaughan, Robert Arthern
Different parts of Antarctica receive different amounts of snowfall each year. In this paper we map the variations of the mean annual snow accumulation across the ice sheet. We also…1 January, 2006 by David Vaughan, Fausto Ferraccioli
Marine and rift sediments exert a fundamental control on ice stream flow in the West Antarctic Ice Sheet, and hence on its mass balance and stability. In contrast, most ice…Read more on East Antarctic ice stream tributary underlain by major sedimentary basin
1 January, 2006 by Eric Wolff, Robert Mulvaney
Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth's climate dynamics. For the last glacial period, ice core studies1,…Read more on One-to-one coupling of glacial climate variability in Greenland and Antarctica
1 January, 2006 by Andrew Clarke, Claire Allen, Dominic Hodgson, David Barnes, Peter Convey
Aim To investigate the major paradigms of intense isolation and little anthropogenic influence around Antarctica and to examine the timings and scales of the modification of the southern polar biota.…Read more on Incursion and excursion of Antarctic biota: past, present and future
1 January, 2006 by David Barnes
Demonstrable examples of marine interference-competition on ecological, and particularly evolutionary, time-scales have been highly confined in space. However, studies of such competition across large-scale space are conversely mere ‘snapshots’ in…Read more on Temporal-spatial stability of competition in marine boulder fields
1 January, 2006 by David Barnes
Bouvet Island is, uniquely, thousands of km from the next nearest land, even other islands. Its Southern Ocean location, isolation and the exposure of its surrounding cliffs have resulted in…Read more on A most isolated benthos: coastal bryozoans of Bouvet Island
1 January, 2006 by David Barnes, Katrin Linse, Peter Enderlein, Simon Morley
Benthic communities in several fjords and sheltered bays of the north coast of South Georgia Island were examined using SCUBA and shore sampling in November 2004. It is one of…Read more on Shallow benthic communities of South Georgia Island
1 January, 2006
Some organisms are particularly appropriate models for investigation of variability in time and space for given environments. The erect bryozoan Cellarinella nutti, an endemic Antarctic species, is one such organism:…1 January, 2006 by Eric Wolff, Robert Mulvaney
Two 788 m conductivity records from ice cores drilled at Dome C, Antarctica, provide an unprecedented opportunity to examine the past roughness of the Antarctic surface. By measuring the distribution…Read more on A 44 kyr paleoroughness record of the Antarctic surface
1 January, 2006 by Andrew Clarke, David Barnes
The variability of Southern Ocean sea-surface temperatures (SST) are important to understanding coastal biology yet are poorly known amongst biologists. We compare sea temperatures at a constant depth (10–20 m)…Read more on Spatial and temporal variation in shallow seawater temperatures around Antarctica
1 January, 2006 by Eric Wolff
Short communication - no abstract1 January, 2006 by Philip Leat
176Hf/177Hf isotopes provide information about the behaviour of so-called immobile elements in subduction environments. Early studies of Hf isotopes in subduction zones reached different conclusions regarding the mobility of high-field-strength…1 January, 2006
This paper combines four years of radar wind data from Halley and Scott Base in an attempt to resolve the zonal structure of the semi-diurnal tide over Antarctica and to…1 January, 2006 by Richard Phillips
An important aspect of foraging ecology is the extent to which different individuals or genders within a population exploit food resources in a different manner. For diving seabirds, much of…1 January, 2006
Free-living nematodes are abundant in all marine habitats, are highly diverse, and can be useful for monitoring anthropogenic impacts on the environment. Despite such attributes, nematodes are effectively ignored by…1 January, 2006
The major ions, sodium (Na+), calcium (Ca2+), and chloride (Cl−), deposited in central Antarctica and preserved in ice cores originate from both marine and continental sources. They provide important proxy…1 January, 2006
The possible existence of endemism among microorganisms resulting from and preserved by geographic isolation is one of the most controversial topics in microbial ecology. We isolated 31 strains of "Spumella-like"…1 January, 2006 by Andrew Clarke, David Barnes, Lloyd Peck
The development of sessile invertebrate assemblages on hard substrata has been studied extensively in temperate and tropical latitudes. Such studies provide insights into a range of ecological processes, and the…1 January, 2006 by Eugene Murphy, Peter Enderlein
Upward-looking acoustic Doppler current profilers (ADCPs) (300 kHz) and echosounders (125 kHz) were deployed on moorings at South Georgia to measure abundance of Antarctic krill continuously over several months. Echoes…1 January, 2006 by Eric Wolff
Cores drilled through the polar ice sheets provide information about past climate and environmental conditions on timescales from decades to hundreds of millennia, and direct records of changes in the…1 January, 2006 by Eric Wolff
Ice cores provide information about past climate and environmental conditions on timescales from decades to hundreds of millennia, and direct records of the composition of the atmosphere. As such, they…Read more on The future of ice coring: International Partnerships in Ice Core Sciences (IPICS)
1 January, 2006 by Geraint Tarling
The interactions between moult phasing, growth and environmental cues in Northern krill (Meganyctiphanes norvegica) were examined through analysing populations at seasonal, weekly, and daily timescales. The analyses were carried out…1 January, 2006
Mesozooplankton are significant consumers of phytoplankton, and have a significant impact on the oceanic biogeochemical cycles of carbon and other elements. Their contribution to vertical particle flux is much larger…1 January, 2006
Extrapair paternities (EPP) are relatively common in passerines, but rare in seabirds. Like most seabirds, albatrosses are long lived, form long-term pair bonds and require biparental care for chick-rearing. Microsatellite…1 January, 2006
Nitrate records from six Greenland ice cores covering the period 1789 to 1995 show a significant correlation in concentration for averaging periods greater than 10 years, as well as an…1 January, 2006
In the summer 2000–01, thermal monitoring of the permafrost active layer within various terrestrial sites covered by lichen, moss or grasses was undertaken at Jubany (King George Island) and Signy…1 January, 2006 by Melody Clark
Background Comparative approaches using protostome and deuterostome data have greatly contributed to understanding gene function and organismal complexity. The family 2 G-protein coupled receptors (GPCRs) are one of the largest…Read more on Evolution of secretin family GPCR members in the metazoa
1 January, 2006
The third primary production algorithm round robin (PPARR3) compares output from 24 models that estimate depth-integrated primary production from satellite measurements of ocean color, as well as seven general circulation…Read more on A comparison of global estimates of marine primary production from ocean color
1 January, 2006 by Jaume Forcada, Richard Phillips
With rare exceptions, avian offspring are continuously attended by one parent for at least the first few days after hatching. The duration of this phase of the nesting cycle is…1 January, 2006 by Richard Phillips
Studies attempting to document reproductive or other pre-lethal senescence effects in wild birds typically face an array of problems, including flaws in statistical analyses, non-adaptive philopatry to deteriorating environments, confounding…1 January, 2006 by Richard Phillips
Although there is increasing evidence that climatic variations during the non-breeding season shape population dynamics of seabirds, most aspects of their winter distribution and ecology remain essentially unknown. We used…1 January, 2006
Lidar observations of polar mesospheric clouds (PMC) were made at Rothera, Antarctica, from December 2002 to March 2005. Overall, 128 hours of PMC were detected among the 459 hours of…1 January, 2006
The diumal variations in the parameters of Pc3 (20–60 mHz) and Pc4 (10–19 mHz) pulsations at latitudes of the dayside cusp and polar cap have been studied using data of…1 January, 2006 by Andrew Clarke
The EASIZ (Ecology of the Antarctic Sea Ice Zone) programme ran from 1994 to 2004, and involved over 150 scientists from more than 17 countries. The main scientific aim was…1 January, 2006 by Andrew Clarke
In recent years, a number of species–energy hypotheses have been developed to explain global patterns in plant and animal diversity. These hypotheses frequently fail to distinguish between fundamentally different forms…1 January, 2006 by Mark Clilverd
During the sudden decrease of geosynchronous electron flux (>2 MeV) of 17:10–17:20 UT, January 21, 2005 large-scale precipitation into the atmosphere was observed. Estimates from ground-based radio propagation experiments at…1 January, 2006 by Mark Clilverd
At Ny Ålesund, Svalbard (78°54′N, 11°53′E, L ∼ 18), a narrowband VLF receiver was used to monitor the behavior of the amplitude of several high-power transmitters located in the Northern…Read more on Modeling polar ionospheric effects during the October-November 2003 solar proton events
1 January, 2006 by Mark Clilverd
We use a model for sunspot number using low-frequency solar oscillations, with periods 22, 53, 88, 106, 213, and 420 years modulating the 11-year Schwabe cycle, to predict the peak…1 January, 2006
The colonization of the underside of rocks normally requires that the material is sufficiently translucent to allow the penetration of photosynthetically active radiation. We examined the underside of 950 opaque…Read more on Hypolithic colonization of opaque rocks in the Arctic and Antarctic polar desert
1 January, 2006 by Martin Collins, Paul Rodhouse
The Southern Ocean cephalopod fauna is distinctive, with high levels of endemism in the squid and particularly in the octopodids. Loliginid squid, sepiids and sepiolids are absent from the Southern…1 January, 2006
We present results of an implementation of the Elastic Viscous Plastic (EVP) sea ice dynamics scheme into the Hadley Centre coupled ocean-atmosphere climate model HadCM3. Although the large-scale simulation of…1 January, 2006 by Peter Convey
Antarctic terrestrial biota are generally limited by the inexorably linked environmental factors of low summer temperature and lack of available water. However, in parts of the Antarctic, both these factors…Read more on Responses of terrestrial Antarctic ecosystems to climate change
1 January, 2006 by Peter Convey
Question: How does geothermal activity influence terrestrial plant colonization, species composition and community development in the Antarctic? Location: South Sandwich Islands, maritime Antarctic. Methods: Bryophytes were documented during a biological…Read more on Geothermal bryophyte habitats in the South Sandwich Islands, maritime Antarctic
1 January, 2006 by Peter Convey
The consequences of climate change are exciting considerable concern worldwide. Parts of Antarctica are facing the most rapid rates of anthropogenic climate change currently seen on the planet. This paper…Read more on Antarctic terrestrial ecosystems: responses to environmental change
1 January, 2006 by Katrin Linse
The isolated Southern Ocean has given rise to specially adapted, endemic species. The uniformity of physical conditions within the Southern Ocean south of the Polar Front is thought to limit…1 January, 2006 by Adrian Jenkins, Hugh Corr, Keith Nicholls
This paper describes the novel technique of using a phase-sensitive radio-echo system to determine the basal melt rate along a short profile near Halley Station on the Brunt Ice Shelf.…Read more on Direct measurements of ice-shelf bottom melting rates by phase sensitive radar
1 January, 2006 by Geraint Tarling
We measured vertical migration of zooplankton in an arctic fjord at 79uN between June and September 2002 and transcending a period of continuous illumination to one of true day and…1 January, 2006 by Dominic Hodgson
Aim There is no previous direct evidence for the occurrence of lacustrine refuges for invertebrate fauna in Antarctica spanning the Last Glacial Maximum (LGM). In the absence of verified LGM…1 January, 2006 by Janet Silk, Vsevolod Afanasyev
In temperate regions, winter presents animals with a number of challenges including depressed food abundance, increased daily energy requirements, higher frequency of extreme weather events and shortened day length. Overcoming…1 January, 2006
At Rothera Research Station (67.3°S, 68.1°W), Antarctica, 296 h of day and nighttime Fe-Boltzmann temperature lidar data were accumulated in 2003. During this time, sporadic iron layers (FeS) were observed…Read more on Statistics of sporadic iron and relation to atmospheric dynamics
1 January, 2006 by Hugh Corr
The polarisation behaviour of radar waves transmitted through Brunt Ice Shelf at a site near Halley has been investigated using a step-frequency radar with a centre frequency of 300 MHz…Read more on Polarisation of radio waves transmitted through Brunt Ice Shelf
1 January, 2006 by Adrian Jenkins, Hugh Corr, Keith Nicholls
We have collected ice penetrating polarimetric radar data on Brunt, George VI and Ronne ice shelves using a vector network analyser as a continuous wave (CW) step-frequency radar. Being a…Read more on Interpretation of polarimetric ice penetrating radar data over Antarctic ice shelves
1 January, 2006
After isostatic correction for their sedimentary fill, the depths of two small oceanic basins in the southern Scotia Sea suggest that both started to open in mid to late Eocene…Read more on Small basins in the Scotia Sea: the Eocene Drake Passage gateway
1 January, 2006 by Vsevolod Afanasyev
By attaching 9-g loggers (recording dusk and dawn times to a memory chip) to the coded leg rings of Barnacle Geese Branta leucopsis caught in a breeding colony at Tobseda…1 January, 2006
We analyze ground-based Fabry-Perot interferometer observations of upper thermospheric (∼250 km) horizontal neutral winds derived from Doppler shifts in the 630.0 nm (red line) nightglow. The winds were measured over…1 January, 2006
We analyze upper thermospheric (∼250 km) nighttime horizontal neutral wind patterns, during geomagnetically quiet (Kp < 3) conditions, over the following locations: South Pole (90°S), Halley (76°S, 27°W), Millstone Hill…1 January, 2006
Images of mesospheric airglow and radar-wind measurements have been combined to estimate the difference in the vertical flux of horizontal momentum carried by high-frequency gravity waves over two dissimilar Antarctic…Read more on Regional variations of mesospheric gravity-wave momentum flux over Antarctica
1 January, 2006
Nitric oxide, which reacts catalytically to destroy ozone, can be produced in great abundance in the middle atmosphere during energetic particle precipitation triggered by solar storms. During the Antarctic winter,…1 January, 2006 by Eugene Murphy
A time-dependent, size-structured, physiologically based krill growth model was used in conjunction with a circulation model to test the hypothesis that Antarctic krill (Euphausia superba) populations at South Georgia are…1 January, 2006 by Adrian Jenkins, Keith Nicholls
The field work during ”Polarstern” cruise ANT XVI/2 aimed to measure circulation and water mass properties in the Atlantic sector of the Southern Ocean, to investigate the contribution of the…1 January, 2006
Sea ice is a two-phase, two-component, reactive porous medium: an example of what is known in other contexts as a mushy layer. The fundamental conservation laws underlying the mathematical description…1 January, 2006 by Fausto Ferraccioli, Philip Leat
New airborne geophysical data reveal subglacial imprints of crustal growth of the Antarctic Peninsula by Mesozoic arc magmatism and terrane accretion along the paleo-Pacific margin of Gondwana. Potential field signatures…Read more on New aerogeophysical view of the Antarctic Peninsula: more pieces, less puzzle
1 January, 2006
Zircons gneisses and migmatites collected from the Antarctic Peninsula have different core–rim hafnium isotope ratio relationships depending on whether evidence for zircon dissolution is present or absent. Two samples contain…1 January, 2006 by Eugene Murphy, Jaume Forcada, Philip Trathan
Climate warming and associated sea ice reductions in Antarctica have modified habitat conditions for some species. These include the congeneric Adélie, chinstrap and gentoo penguins, which now demonstrate remarkable population…