Showing 11868 items
1 January, 2007
1] The impact of extreme sea ice initial conditions on modelled climate is analysed for a fully coupled atmosphere ocean sea ice general circulation model, the Hadley Centre climate model…Read more on Impact of instantaneous sea ice removal in a coupled general circulation model
1 January, 2007 by Katrin Linse
The abyssal depths of the polar oceans are thought to be low in diversity compared with the shallower polar shelves and temperate and tropical deep-sea basins. Our recent study on…1 January, 2007 by Claire Waluda
Cephalopod movement occurs during all phases of the life history, with the abundance and location of cephalopod populations strongly influenced by the prevalence and scale of their movements. Environmental parameters,…Read more on Approaches to resolving cephalopod movement and migration patterns
1 January, 2007 by Mark Clilverd
In this study we combine odd nitrogen (NOx) observations from the GOMOS and POAM III instruments with a radio wave ionization index to provide a detailed description of the generation…1 January, 2007
Interferometric synthetic aperture radar data show that Devon Ice Cap (DIC), northern Canada, is drained through a network of 11 glacier systems. More than half of all ice discharge is…1 January, 2007 by Adrian Jenkins, Deb Shoosmith
Introduction This report provides an overview of a 2006 cruise to the Amundsen Sea, the oceanographic data collected, and how we intend to use these data to further our understanding…Read more on Oceanographic fieldwork in the Amundsen Sea: an overview of cruise JR141
1 January, 2007 by Andy Smith, Dominic Hodgson, David Pearce, Ed King, Hugh Corr, Keith Makinson, Richard Hindmarsh, Richard Hindmarsh
Antarctic subglacial lakes have, over the past few years, been hypothesised to house unique forms of life and hold detailed sedimentary records of past climate change. Testing this hypothesis requires…1 January, 2007
The timing of West Antarctic Ice Sheet (WAIS) expansion and retreat during the last glacial cycle is crucial to evaluating the processes controlling ice sheet fluctuations. There is currently debate…1 January, 2007 by Eric Wolff, Howard Roscoe
During springtime in the polar regions, unique photochemistry converts inert halide salt ions (e.g. Br-) into reactive halogen species (e.g. Br atoms and BrO) that deplete ozone in the boundary…Read more on Halogens and their role in polar boundary-layer ozone depletion
1 January, 2007
The first measurements of peroxy (HO2+RO2) and hydroxyl (OH) radicals above the arctic snowpack were collected during the summer 2003 campaign at Summit, Greenland. The median measured number densities for…1 January, 2007 by Roger Worland
Collembola are abundant and functionally significant arthropods in sub-Antarctic terrestrial ecosystems, and their importance has increased as a consequence of the many invasive alien species that have been introduced to…1 January, 2007 by David Barnes
The response of scavengers to a feeding cue at Adelaide Island, West Antarctic Peninsula was investigated using a baited video camera system. Fourteen experimental deployments, each lasting 72 h were…1 January, 2007
Ice scouring is one of the 5 most significant natural forces acting on ecosystems, yet very few data exist linking the intensity of ice disturbance with parameters of benthic community…Read more on Ice disturbance intensity structures benthic communities in nearshore Antarctic waters
1 January, 2007 by David Barnes
Ice scour disturbance has a significant effect on the physical and biological characteristics of polar benthos. A series of grids, each consisting of 25 markers, were deployed along depth transects…1 January, 2007 by David Barnes
Ice scouring is a key structuring force acting on high latitude shallow benthic communities. Despite its importance, detailed studies of scoured communities are still rare. Here we report the ecological…1 January, 2007 by Ed King
GPS crustal velocity data from the Scotia and South Sandwich plates, transform azimuths, spreading data, and an updated earthquake slip vector catalog provide the first Scotia and South Sandwich plate…1 January, 2007 by Andy Smith, David Vaughan, Keith Makinson, Keith Nicholls
What happens beneath a glacier affects the way it flows and the landforms left behind when it retreats. Direct observations from beneath glaciers are, however, rare and the subglacial environment…1 January, 2007 by Andy Smith
Recent applications of the normal-incidence seismic reflection technique to studying subglacial conditions are summarized. Some of the important aspects of the technique are discussed, including critical acquisition parameters and particular…Read more on Subglacial bed properties from normal-incidence seismic reflection data
1 January, 2007 by Peter Fretwell
This paper contributes to knowledge of Holocene relative sea level change along the mainland Ayrshire coast and offshore Isle of Bute, SW Scotland, UK, where few such studies have previously…1 January, 2007 by Dominic Hodgson, James Smith
George VI Ice Shelf is the largest ice shelf on the west coast of the Antarctic Peninsula, covering a total area of 25 000 km2. The northern ice front of…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
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
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 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
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
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 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…23 October, 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 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
9 August, 2006 by Mark Clilverd
High altitude nuclear explosions (HANEs) and geomagnetic storms can produce large scale injections of relativistic particles into the inner radiation belts. It is recognised that these large increases in >1…Read more on The atmospheric implications of radiation belt remediation
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…12 July, 2006 by Robert Mulvaney
Four trihalomethane (THM; CHCl3, CHBrCl2, CHBr2Cl and CHBr3) and two dihalomethane (DHM; CH2BrCl and CH2Br2) trace gases have been measured in air extracted from polar firn collected at the North…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
7 March, 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 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 March, 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 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…13 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 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