Showing 13481 items
1 January, 2007 by Dominic Hodgson, James Smith, Stephen Roberts
We use lake sediment records from an epishelf lake on Alexander Island to provide a detailed picture of the Holocene history of George VI Ice Shelf (GVI-IS). Core analyses included;…1 January, 2007 by Kevin Newsham, Peter Convey
We measured the responses of pigments and chlorophyll a fluorescence parameters of the Antarctic leafy liverwort Cephaloziella varians to snowmelt during austral spring 2005 at Rothera Point on the western…1 January, 2007 by Iain Staniland
We tested the prediction that lactating fur seals (Arctocephalus gazella) at South Georgia will take prey of greater energy density with increasing distance of foraging from the colony. The study…1 January, 2007 by Katrin Linse
The opening of the Drake Passage, establishment of the Polar Front and the onset of cooling around the Eocene-Oligocene boundary have been recognised as the most significant events in shaping…Read more on Evolution of the Antarctic marine fauna: what can DNA and fossils tell us?
1 January, 2007
Recent molecular studies investigating higher-level phylogenetics of coleoid cephalopods (octopuses, squids and cuttlefishes) have produced conflicting results. A wide range of sequence alignment and analysis methods are used in cephalopod…1 January, 2007
The concept of a Barcode of Life Database (BoLD) for the Class Cephalopoda (Phylum Mollusca) was introduced at the Cephalopod International Advisory Council (CIAC) symposium in Hobart, Australia, February 2006.…Read more on A barcode of life database for the Cephalopoda? Considerations and concerns
1 January, 2007 by Nigel Meredith
Radiation belt electrons can interact with various modes of plasma wave in their drift orbits about the Earth, including whistler-mode chorus outside the plasmasphere, and both whistler-mode hiss and electromagnetic…1 January, 2007 by Nigel Meredith
Outer zone radiation belt electrons can undergo gyroresonant interaction with various magnetospheric wave modes including whistler-mode chorus outside the plasmasphere and both whistler-mode hiss and electromagnetic ion cyclotron (EMIC) waves…1 January, 2007 by Eugene Murphy, Geraint Tarling, Peter Ward, Sally Thorpe
The high concentration of adult Antarctic krill Euphausia superba Dana around South Georgia, Antarctica, is a product of immigration and not local recruitment. We investigated whether reproduction and early larval…1 January, 2007 by Geraint Tarling, Peter Ward
A stage- and age-structured model was constructed to simulate stage-abundance patterns of Rhincalanus gigas in a data set consisting of over 80 yr of net-catch observations in the Scotia Sea.…1 January, 2007 by Andrew Clarke
Stable, hydrogen-burning, M dwarf stars make up about 75% of all stars in the Galaxy. They are extremely long-lived, and because they are much smaller in mass than the Sun…Read more on A reappraisal of the habitability of planets around M dwarf stars
1 January, 2007 by Eric Wolff, Liz Thomas, Robert Mulvaney
We present a collection of high-resolution chemistry and stable isotope records from the plateau of the Greenland ice cap during the cold event 8200 yr ago. Using a composite of…1 January, 2007 by Mark Clilverd
Nighttime ionospheric D region heights and electron densities are determined from an extensive set of VLF radio phase and amplitude observations. The D region parameters are characterized by the traditional…Read more on Nighttime ionospheric D-region parameters from VLF phase and amplitude
1 January, 2007 by Nigel Meredith, Richard Horne
Energetic electrons (≥50 keV) are injected into the slot region (2 < L < 4) between the inner and outer radiation belts during the early recovery phase of geomagnetic storms.…1 January, 2007 by Eugene Murphy, Jaume Forcada, Philip Trathan
The Southern Ocean is a major component within the global ocean and climate system and potentially the location where the most rapid climate change is most likely to happen, particularly…1 January, 2007 by John Turner
In recent years, there has been an unprecedented level of interest in the climate and environmental conditions of the polar regions. The discovery of the Antarctic ozone hole, record low…Read more on Polar meteorology – understanding global impacts
1 January, 2007 by John Turner
The Antarctic is the windiest continent on Earth, with many of the coastal research stations affected by strong katabatic winds. The strength and persistence of the near-surface winds was noted…1 January, 2007 by John Turner
We contrast recent climatic and environmental changes and their causes in the Arctic and the Antarctic. There are continuing increases in surface temperatures, losses of sea ice and tundra, and…Read more on An Arctic and Antarctic perspective on recent climate change
1 January, 2007 by Robert Larter
An understanding of the glacial history of Pine Island Bay (PIB) is essential for refining models of the future stability of the West Antarctic Ice Sheet (WAIS). New multichannel seismic…1 January, 2007 by Mark Clilverd
As a consequence of alterations of atmospheric chemical composition due to anthropogenic emissions, Earth's ionosphere and thermosphere are expected to change. A number of authors tried to detect signs of…Read more on Unravelling signs of global change in the ionosphere
1 January, 2007 by Kevin Newsham
A recent study identified a fungal isolate from the Antarctic leafy liverwort Cephaloziella varians as the ericoid mycorrhizal associate Rhizoscyphus ericae. However, nothing is known about the wider Antarctic distribution…1 January, 2007 by Geraint Tarling
Timing of reproduction influences future prospects of offspring and therefore the reproductive value of parents. Early offspring are often more valuable than later ones when food availability and predation risk…1 January, 2007
The Phanerozoic is comprised of over 540 million years and, with its defining accompaniment of abundant complex life, provides us with a unique perspective on the extremes of climate change.…Read more on Climate and geology – a Phanerozoic perspective
1 January, 2007
We present a new conceptual model where supercontinents, by focusing subduction on narrow areas of the 670 km mantle discontinuity, trigger superplume events and initiate their own fragmentation. This supercontinent-triggered…1 January, 2007 by David Vaughan
A recent report from Working Group I of the Intergovernmental Panel on Climate Change [IPCC, 2007] highlighted the increasingly precise observations of sea level rise that are obtainable from satellite…1 January, 2007 by David Vaughan, Robert Arthern
Ice sheet retreat, hypotheses of instability could be missing important processes that limit the rate or extent of retreat, or conversely, Ice sheet behavior is strongly influenced by processes at…Read more on Why is it hard to predict the future of ice sheets?
1 January, 2007 by David Vaughan, Hugh Corr
Subglacial Lake Ellsworth (SLE) was identified using reconnaissance data collected in the 1970s, here we present more detailed surveys. SLE lies beneath 3.2 km of ice in a subglacial valley…Read more on Topographic and hydrological controls on Subglacial Lake Ellsworth, West Antarctica
1 January, 2007 by Mark Clilverd
We utilise hydroxyl observations from the MLS/Aura satellite instrument to study the latitudinal extent of particle forcing in the northern polar region during the January 2005 solar proton event. MLS…1 January, 2007 by Dominic Hodgson
There is a long-standing belief that microbial organisms have unlimited dispersal capabilities, are therefore ubiquitous, and show weak or absent latitudinal diversity gradients. In contrast, using a global freshwater diatom…Read more on Historical processes constrain patterns in global diatom diversity
1 January, 2007 by Adrian Jenkins
Glaciers which drain the West Antarctic Ice Sheet (WAIS) into the Amundsen Sea are accelerating and thinning rapidly. These observations have been attributed to the regional oceanography whereby heat contained…Read more on Oceanic heat transport onto the Amundsen Sea shelf through a submarine glacial trough
1 January, 2007 by Emma Young, Peter Ward, Sally Thorpe
During late December 2004 and early January 2005 the plankton community to the south and west of South Georgia was investigated. Satellite imagery had shown the surface expression of a…1 January, 2007 by Peter Ward
In this study we report the abundance, fecundity and an index of mortality of Oithona similis across a large latitudinal and temperature range within the Southern Ocean. The abundance of…1 January, 2007
The first underwater digital photographs obtained by cameras carried by Shags PhaJacrocorax aristoteJis showed the birds diving in areas dominated by soft coral Alcyonium digitatum and feeding on butterfish PhoJis…1 January, 2007 by Paul Holland
A drag law accounting for Ekman rotation adjacent to a flat, horizontal boundary is proposed for use in a plume model that is written in terms of the depth-mean velocity.…Read more on The effect of a new drag law parameterization on Ice Shelf Water plume dynamics.
1 January, 2007 by Claus-Dieter Hillenbrand
This paper explores the effects of preservation and taphonomy on the ultrastructure of recent and fossil (Quaternary and Neogene) Globigerinoides using scanning electron microscopy and thin section petrography. We show…1 January, 2007 by Tom Jordan
Magnetic anomaly data are presented from a new helicopter-borne high-resolution aeromagnetic survey in southern McMurdo Sound. Anomaly data have been acquired at a common 305 m elevation above the McMurdo…1 January, 2007 by Eric Wolff
Polar ice cores contain, in trapped air bubbles, an archive of the concentrations of stable atmospheric gases. Of the major non-CO2 greenhouse gases, methane is measured quite routinely, while nitrous…Read more on Methane and nitrous oxide in the ice core record
1 January, 2007 by Eric Wolff
Predicting the future of our Earth and its climate requires models that contain good representations of the key processes that might take place. Our only way to determine what these…Read more on Frozen in time: the chemistry of polar ice cores
1 January, 2007 by Eric Wolff
Ice cores have been a cornerstone of global change research in recent decades. Europe has been at the forefront of this science, particularly through the GRIP and EPICA projects funded…1 January, 2007 by Eric Wolff
Recent recommendations for the expression of time units in Quaternary Science Reviews appear still to leave room for confusion. Here, I propose that the entire palaeoclimate community should agree on…1 January, 2007 by Anna Jones, Eric Wolff
Ice cores provide the most direct evidence available about the past atmosphere. For long-lived trace gases, ice cores have provided clear evidence that in the last two centuries, concentrations of…Read more on Past atmospheric composition and chemistry from ice cores – progress and prospects
1 January, 2007
We show that correlated dynamics and long time memory persist in self-organized criticality (SOC) systems even when forced away from the defined critical point that exists at vanishing drive strength.…1 January, 2007 by Roger Worland
The Antarctic collembolan, Cryptopygus antarcticus (Willem), can switch its supercooling point (SCP) between 'winter' and 'summer' modes of cold hardiness over a matter of hours. High resolution temporal scaling of…1 January, 2007 by Robert Mulvaney
The atmospheric histories of two potent greenhouse gases, tetrafluoromethane (CF4) and hexafluoroethane (C2F6), have been reconstructed for the 20th century based on firn air measurements from both hemispheres. The reconstructed…Read more on Atmospheric trends and radiative forcings of CF4 and C2F6 inferred from firn air
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 January, 2007 by Peter Convey
The diversification of Antarctic springtails and mites is likely to have occurred as a result of the glaciation and isolation of the Antarctic continent completed by ~10 million years ago,…1 January, 2007
Pi1 observations, because of their higher frequency, hold the promise of providing better temporal resolution for accurate timing of substorm onsets, thus continuing to be a matter of considerable importance…Read more on An attempt to locate substorm onsets using Pi1 signatures
1 January, 2007 by Fausto Ferraccioli, Tom Jordan
Subglacial sediments are an important control on fast flowing ice in West Antarctica but their spatial distribution over catchment-wide areas is still largely unknown. Previously, airborne gravity anomalies could not…Read more on Locating subglacial sediments across West Antarctica with isostatic gravity anomalies
1 January, 2007 by John Turner, Thomas Bracegirdle
Sea ice plays a key role for climate and is important as habitat and for human activities and economies. Observations show and models indicate that climate and sea-ice regimes are…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…