Showing 13487 items
1 January, 2009 by Emily Shuckburgh
A new diagnostic (the "Lyapunov diffusivity'') is presented that has the ability to quantify isentropic mixing in diffusion units and detects local mixing events by describing latitude-longitude variability. It is…1 January, 2009 by Huw Griffiths
The Southern Ocean is of unique ecological, biogeographic and political interest, as noted by your Editorial 'The way ahead for polar science' (Nature 457, 1057; 2009). Given the rate and…Read more on Polar science: bid for freely accessible biodiversity archive
1 January, 2009 by Dominic Hodgson
Recent data revealed that metazoans such as mites and springtails have persisted in Antarctica throughout several glacial-interglacial cycles, which contradicts the existing paradigm that terrestrial life was wiped out by…1 January, 2009 by Michael Thorne, Melody Clark
Background: Microscopic monogonont rotifers, including the euryhaline species Brachionus plicatilis, are typically found in water bodies where environmental factors restrict population growth to short periods lasting days or months. The…1 January, 2009 by Richard Horne
This special issue of the Journal of Atmospheric and Solar-Terrestrial Physics is devoted to research into high speed solar wind streams (HSSs) and their effects on the region of near-Earth…1 January, 2009
Sixty species of Ostracoda have been recovered from Cenomanian, Santonian and Maastrichtian strata in New Zealand, and late Campanian sediments on Snow Hill and James Ross islands in the Antarctic…1 January, 2009 by Michael Meredith
Monitoring the sources and fate of freshwater in the East Greenland Current (EGC) is important, as this water has the potential to suppress deep convection in the Nordic and Labrador…Read more on The sources and fate of freshwater exported in the East Greenland Current
1 January, 2009
Improved sampling technologies, international observing networks, and data synthesis efforts are providing an unprecedented view of the global patterns and decadal variability of surface-ocean partial pressure of carbon dioxide (pCO(2))…Read more on Surface-ocean CO2 variability and vulnerability
1 January, 2009 by Richard Hindmarsh, Richard Hindmarsh
Using the finite-element code Elmer, we show that the full Stokes modeling of the ice-sheet/ice-shelf transition we propose can give consistent predictions of grounding-line migration. Like other marine ice-sheet models…Read more on Full Stokes modeling of marine ice sheets: influence of the grid size
1 January, 2009 by Robert Larter
An animated reconstruction shows South Pacific plate kinematics, in the reference frame of West Antarctica, between 55 Ma and the present-day. The ocean floor in the region formed due to…1 January, 2009 by Robert Larter
Decades after the recognition of the West Antarctic Rift System, and in spite of its global importance, the location and nature of the plate boundary it formed at are unknown…Read more on West Antarctic Rift System in the Antarctic Peninsula
1 January, 2009
A tectonic model of the Weddell Sea is built by composing a simple circuit with optimized rotations describing the growth of the South Atlantic and SW Indian oceans. The model…Read more on Gondwana breakup and plate kinematics: Business as usual
1 January, 2009
The breeding and feeding grounds of most humpback whale populations are well known. Their preference for shallow, subtropical waters in winter, where they calve and mate (Clapham 1996), often brings…Read more on Feeding grounds of the western South Atlantic humpback whale population
1 January, 2009
Fatty acids profiles of Emiliania huxleyi strain CCMP1516 were determined in a virus-induced culture crash with E. huxleyi virus 86 (EhV-86). As cell numbers declined in the infected cultures due…1 January, 2009 by Fausto Ferraccioli
New aeromagnetic data image the extent and spatial distribution of Cenozoic magmatism and older basement features over the Admiralty Block of the Transantarctic Mountains. Digital enhancement techniques image magmatic and…1 January, 2009 by Fausto Ferraccioli, Hugh Corr, Tom Jordan
The Wilkes Subglacial Basin represents all approximately 1400 kin-long and Lip to 600 kill wide Subglacial depression, buried beneath the over 3 km-thick East Antarctic Ice Sheet. Contrasting models, including…1 January, 2009
The presence of major crystalline basement provinces at depth in NW Ireland is inferred from in situ Hf isotope analysis of zircons from granitoid rocks that cut structurally overlying metasedimentary…1 January, 2009 by Gareth Marshall
This second paper examines the Southern Hemisphere annular mode (SAM) variability from reconstructions, observed indices, and simulations from 17 Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) models…1 January, 2009 by Iain Staniland, Jaume Forcada
Correctly quantifying the impacts of rare apex marine predators is essential to ecosystem-based approaches to fisheries management, where harvesting must be sustainable for targeted species and their dependent predators. This…1 January, 2009 by Jaume Forcada, Philip Trathan
Penguins are adapted to live in extreme environments, but they can be highly sensitive to climate change, which disrupts penguin life history strategies when it alters the weather, oceanography and…Read more on Penguin responses to climate change in the Southern Ocean
1 January, 2009 by Elaina Ford
A dynamical link is demonstrated between the equatorial quasi-biennial oscillation (QBO) and high-latitude mesospheric zonal winds recorded by an Imaging Doppler Interferometer (IDI) at Halley, Antarctica. Above ~80 km eastward…Read more on QBO effects on Antarctic mesospheric winds and polar vortex dynamics
1 January, 2009 by Richard Phillips
The Black-browed Albatross Thalassarche melanophris is a long-lived procellariiform that typically nests colonially and exhibits low fecundity. Previous studies on albatrosses have focussed on the bottom-up effects of food supply…1 January, 2009
The multi-scale nature and climate noise properties of teleconnection indices are examined by using the Empirical Mode Decomposition (EMD) procedure. The EMD procedure allows for the analysis of non-stationary time…1 January, 2009
In this study the authors apply a recently developed clustering method for the systematic identification of metastable atmospheric regimes in high-dimensional datasets generated by atmospheric models. The novelty of this…Read more on Systematic Metastable Atmospheric Regime Identification in a AGCM
1 January, 2009 by Mervyn Freeman
Superposed epoch analyses have shown that, on average, the interplanetary magnetic field (IMF) turns northward close to substorm onset. This has been commonly accepted as evidence for the substorm onset…1 January, 2009 by Alexander Tate, Mark Belchier, Peter Fretwell
We introduce a new bathymetric compilation of the area around South Georgia in the Southern Ocean. Using a variety of data sources including multi and single-beam swath bathymetry we have…Read more on Compilation of a new bathymetric dataset of South Georgia
1 January, 2009 by Philip Trathan, Peter Fretwell
Aim To map and assess the breeding distribution of emperor penguins (Aptenodytes forsteri) using remote sensing. Location Pan-Antarctic. Methods Using Landsat ETM satellite images downloaded from the Landsat Image Mosaic…Read more on Penguins from space: faecal stains reveal the location of emperor penguin colonies
1 January, 2009 by Markus Frey
Atmospheric hydroperoxides (ROOH) were measured at Summit, Greenland (72.97 degrees N, 38.77 degrees W) in summer 2003 (SUM03) and spring 2004 (SUM04) and South Pole in December 2003 (SP03). The…1 January, 2009 by Markus Frey
The nitrogen (delta N-15) and triple oxygen (delta O-17 and delta O-18) isotopic composition of nitrate (NO3-) was measured year-round in the atmosphere and snow pits at Dome C, Antarctica…1 January, 2009 by Andrew Clarke, Lloyd Peck
Widespread recognition of the importance of biological studies at large spatial and temporal scales, particularly in the face of many of the most pressing issues facing humanity, has fueled the…1 January, 2009 by Ed King
A structural glaciological description and analysis of surface morphological features of the Larsen C ice shelf, Antarctic Peninsula, is derived from satellite images spanning the period 1963-2007. The data are…Read more on Surface structure and stability of the Larsen C ice shelf, Antarctic Peninsula
1 January, 2009 by Vsevolod Afanasyev
To test the potential effects of winds on the migratory detours of shearwaters, transequatorial migrations of 3 shearwaters, the Manx Puffin us puffinus, the Cory's Calonectris diomedea, and the Cape…Read more on Influence of sea surface winds on shearwater migration detours
1 January, 2009 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
The presence of a complex bedform arrangement on the sea floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-temporal record of flow related…1 January, 2009 by Richard Phillips
Several species of seabirds show cyclic patterns of attendance at their nesting colonies. We examined the patterns of variation in the numbers of Cory's shearwater at three colonies (two oceanic…1 January, 2009 by Katrin Linse
The Census of Antarctic Marine Life (CAML) aims to collate DNA barcode data for Antarctic marine species. DNA barcoding is a technique that uses a short gene sequence from a…1 January, 2009
We measured daily energy expenditure (DEE) continuously for a whole year in a free ranging bird, the macaroni penguin Eudyptes chrysolophus. We combined these measurements with concurrently recorded foraging behaviour,…1 January, 2009
The movement of marine vertebrates has been tracked using a variety of techniques, all of which depend on the external attachment of a transmitting or recording device. However, these devices…Read more on Tracking macaroni penguins during long foraging trips using ‘behavioural geolocation’
1 January, 2009 by David Barnes, Huw Griffiths, Katrin Linse
To investigate whether the biogeographical regions proposed by J. W. Hedgpeth and widely adopted by other authors hold true, are an oversimplification or with further data might show a unified…Read more on Towards a generalized biogeography of the Southern Ocean benthos
1 January, 2009 by Adrian Jenkins, Hilmar Gudmundsson
Surface ice-flow velocities measured at stakes on Rutford Ice Stream, West Antarctica, covering a period of similar to 25 years are analysed for evidence of temporal variations in flow. No…1 January, 2009 by Richard Phillips
The migratory movements of seabirds (especially smaller species) remain poorly understood, despite their role as harvesters of marine ecosystems on a global scale and their potential as indicators of ocean…1 January, 2009 by Howard Roscoe
More than 40 years of radiosonde data from two Antarctic stations are examined for changes in the date of the final stratospheric warming that occurs each year as the vortex…1 January, 2009
Life-time records of the trophic sources of carbon, nitrogen and of growth rate can be generated from biogenic structures that show accretionary growth, including fish scales, whale baleen and the…1 January, 2009 by Lloyd Peck
The cost of overcoming prey defenses relative to the value of internal tissues is a key criterion in predator/prey interactions. Optimal foraging theory predicts: (1) specific sizes of prey will…1 January, 2009
This study has investigated the three-dimensional movement of clasts within deformation till, using embedded wireless probes. These probes were part of an environmental sensor network, which measured subglacial properties (temperature,…1 January, 2009 by Elaine Fitzcharles, Philip Trathan
Dimorphism in various morphological traits is widely used to sex birds. However, when a threshold is set and there is overlap in the distribution of traits between sexes, there will…1 January, 2009 by Peter Fretwell
The results of a field spectroscopy campaign that aimed to provide ground truth data for validation of NDVI-based vegetation maps of the region around the British Antarctic Survey Rothera Research…Read more on Field reflectance spectroscopy of sparse vegetation cover on the Antarctic peninsula
1 January, 2009 by Martin Collins
A study of the reproductive biology of the loliginid squid, Alloteuthis subulata in the North Sea, Irish Sea and Portuguese waters was carried out. A predominance of small squid (1 January, 2009
The mid-Pliocene warm period (ca. 3 to 3.3 million years ago) has become an important interval of time for palaeoclimate modelling exercises, with a large number of studies published during…1 January, 2009 by Claus-Dieter Hillenbrand, Robert Larter
This chapter explores the Middle Miocene to Pliocene terrestrial and marine records of Antarctica and the Southern Ocean. The structure of the chapter makes a clear distinction between terrestrial and…Read more on Middle Miocene to Pliocene history of Antarctica and the Southern Ocean
1 January, 2009 by Michael Meredith
The polar foraminifera Neogloboquadrina pachyderma (sinistral) dominates assemblages from the high latitude Southern Ocean, which plays a key role in determining past climate due to the tight linkage between Antarctic…1 January, 2009 by Roger Worland
Survival in microhabitats that experience extreme fluctuations in water availability and temperature requires special adaptations. To withstand such environmental conditions, tardigrades, as well as some nematodes and rotifers, enter a…Read more on High-temperature tolerance in anhydrobiotic tardigrades is limited by glass transition
1 January, 2009 by Roger Worland
Many limno-terrestrial tardigrades live in unstable habitats where they experience extreme environmental conditions such as drought, heat and subzero temperatures. Although their stress tolerance is often related only to the…1 January, 2009 by Philip Trathan, Simeon Hill
The ecosystem approach to fisheries attempts to define objectives for target species, the wider ecosystem, and critically, the fishery itself. Proposals for implementing the approach often include spatial restrictions on…1 January, 2009 by Claus-Dieter Hillenbrand, Robert Larter
The Belgica Trough and the adjacent Belgica Trough Mouth Fan in the southern Bellingshausen Sea (Pacific sector of the Southern Ocean) mark the location of a major outlet for the…1 January, 2009 by Claus-Dieter Hillenbrand
Modern global warming is likely to cause future melting of Earth's polar ice sheets that may result in dramatic sea-level rise. A possible collapse of the West Antarctic Ice Sheet…1 January, 2009 by Richard Hindmarsh, Richard Hindmarsh
A finite-difference model for the calculation of radar layer geometries in large ice masses is presented. Balance velocities are used as coefficients in the age equation and in the heat…Read more on A large-scale numerical model for computing isochrone geometry
1 January, 2009 by Dominic Hodgson
In this paper we present geological evidence from the Larsemann Hills (Lambert Glacier – Amery Ice Shelf region, East Antarctica) of marine sediments at an altitude of c. 8 m…1 January, 2009 by Dominic Hodgson, James Smith, Stephen Roberts
Direct exploration of subglacial lakes buried deep under the Antarctic Ice Sheet has yet to be achieved. However, at retreating margins of the ice sheet, there are a number of…Read more on Exploring former subglacial Hodgson Lake, Antarctica. Paper II: palaeolimnology
1 January, 2009 by Andreas Cziferszky, Dominic Hodgson, James Smith, Joanne Johnson, Stephen Roberts
At retreating margins of the Antarctic Ice Sheet, there are a number of locations where former subglacial lakes are emerging from under the ice but remain perennially ice-covered. This paper…1 January, 2009 by Jaume Forcada
Twinning in natural pinniped populations is often inferred from observations of suckling behavior, but this approach has been criticized because nonfilial nursing occurs at high frequencies in many seal species.…Read more on Genetic analysis of twinning in Antarctic fur seals (Arctocephalus gazella)
1 January, 2009 by Adrian Jenkins, David Vaughan, Hugh Corr, Paul Holland
It is argued that Larsen Ice Shelf contains marine ice formed by oceanic freezing and other mechanisms. Missing basal returns in airborne radar soundings and observations of a smooth and…1 January, 2009 by Mai Mai Lam, Richard Horne
Relativistic electron precipitation changes the chemistry of the upper atmosphere and depletes ozone, but the spatial and temporal distributions are poorly known. Here we survey more than 9 years of…1 January, 2009 by Richard Horne
While policy-makers discuss the benefits of manned spaceflight to the moon and beyond, scientists and engineers are considering how to protect astronauts from the harsh realities of space. During the…1 January, 2009 by Andrew Clarke
Sea-to-air emissions of bromocarbon gases are known to play an important role in atmospheric ozone depletion. In this study, seawater concentrations of bromoform (CHBr3) and dibromomethane (CH2Br2) were measured regularly…1 January, 2009
Solar radiation management (SRM) geoengineering has been proposed as one means of helping avoid the occurrence of dangerous climate change and undesirable state transitions ('tipping points') in the Earth system.…Read more on The fate of the Greenland Ice Sheet in a geoengineered, high CO2 world
1 January, 2009 by Mervyn Freeman
With the arrival of the Cassini spacecraft at Saturn in July 2004, there have been quasi-continuous observations of Saturn kilometric radiation (SKR) emissions. Exploration of the nightside magnetosphere has revealed…1 January, 2009 by Roger Worland
It is widely held both in the physiological literature, and more generally, that the average characteristics of species within an assemblage differ among sites. Such generalizations should be based on…1 January, 2009
A novel technique is used to examine northern hemisphere midlatitude longitudinal variations in ionospheric long-term trends. Differences in hour-by-hour monthly median ionospheric parameters between equilatitudinal observatory pairs are analysed for…Read more on Longitudinal variation in E- and F-region ionospheric trends
1 January, 2009 by Joanne Johnson
Knowledge of the thickness, extent and basal thermal conditions of ice cover on Antarctica during past climatic fluctuations is essential if we are to accurately predict the contribution from the…1 January, 2009 by Anna Jones, Eric Wolff, Gareth Marshall, Howard Roscoe, Neil Brough
The source of bromine that drives polar boundary layer ozone depletion events (ODEs) is still open to some debate. While ODEs are generally noted to form under conditions of a…Read more on BrO, blizzards, and drivers of polar tropospheric ozone depletion events
1 January, 2009 by Gareth Marshall
Seasonal reconstructions of the Southern Hemisphere annular mode (SAM) index are derived to extend the record before the reanalysis period, using station sea level pressure (SLP) data as predictors. Two…Read more on Historical SAM variability. Part I: Century-length seasonal reconstructions
1 January, 2009 by Eric Wolff
This review of late-Holocene palaeoclimatology represents the results from a PAGES/CLIVAR Intersection Panel meeting that took place in June 2006. The review is in three parts: the principal high-resolution proxy…1 January, 2009 by Fausto Ferraccioli, Hugh Corr, Tom Jordan
Understanding Antarctic volcanoes is important as they provide a window on magmatic and tectonic processes of the Antarctic plate and contain datable records of ice-sheet changes. We present the results…Read more on Airborne gravity reveals interior of Antarctic volcano
1 January, 2009 by David Vaughan
We use models constrained by remotely sensed data from Pine Island and Thwaites Glaciers, West Antarctica, to infer basal properties that are difficult to observe directly. The results indicate strong…1 January, 2009 by Chester Sands, David Barnes
Concerted efforts are being made to understand the current and past processes that have shaped Antarctic biodiversity. However, high rates of new species discoveries, sampling patchiness and bias make estimation…1 January, 2009 by David Vaughan, Hugh Corr
This paper presents an overview of internal layering across Pine Island Glacier, West Antarctica, as measured from airborne-radar data acquired during a survey conducted by the British Antarctic Survey and…1 January, 2009 by Gareth Marshall
The southern annular mode (SAM) has a well-established impact on climate in the Southern Hemisphere. The strongest response in surface air temperature (SAT) is observed in the Antarctic, but the…Read more on Climate impacts of the southern annular mode simulated by the CMIP3 models
1 January, 2009 by Victoria Peck
Three dissolution events ca. 16 Ma, 15.5 Ma, and 14.3 Ma ago have been identified in sediments from the Congo Fan. Multiproxy benthic foraminiferal and sedimentary records suggest an expanded…1 January, 2009 by Ed King
Rutford Ice Stream, West Antarctica, drains a catchment of >45 000 km(2) into the Ronne Ice Shelf through a 26 km wide, 2.4 km deep subglacial trough adjacent to the…1 January, 2009 by Ed King, Richard Hindmarsh, Richard Hindmarsh
Most discharge from large ice sheets takes place through fast-flowing ice streams and their speed is strongly modulated by interactions between the ice and the underlying sediments. Seismic surveys and…Read more on Formation of mega-scale glacial lineations observed beneath a West Antarctic ice stream
1 January, 2009
The accurate estimation of scaling exponents is central in the observational study of scale-invariant phenomena. Natural systems unavoidably provide observations over restricted intervals; consequently, a stationary stochastic process time series…Read more on Pseudononstationarity in the scaling exponents of finite-interval time series
1 January, 2009 by Thomas Bracegirdle
The spatial and temporal distributions of marine cold air outbreaks (MCAOs) over the northern North Atlantic have been investigated using re-analysis data for the period from 1958 to 2007. MCAOs…1 January, 2009
A comparison was made of the ground-based and satellite total ozone content (TOC) measurements in the atmosphere over the Antarctic stations Vernadsky, Halley and Amundsen–Scott and the Arctic station Barrow.…1 January, 2009 by David Barnes
Three new cheilostome bryozoans species were discovered in the collections of the BIOPEARL I cruise to the Scotia Arc. The species were found on boulders from the continental slope and…Read more on A new genus and three new species of Antarctic cheilostome Bryozoa
1 January, 2009 by Gareth Marshall, Howard Roscoe, John Turner, Steve Colwell, Thomas Lachlan-Cope
Over the last 30 years, Antarctic mid-tropospheric temperatures in winter have increased by 0.5 K per decade, the largest regional tropospheric warming observed. Over this period, amounts of polar stratospheric…1 January, 2009 by Mai Mai Lam, Nigel Meredith, Richard Horne, Sarah Glauert
Coronal holes produce high speed solar wind streams (HSS) that subsequently interact with the slower downstream solar wind forming co-rotating interaction regions (CIRs). The CIR/HSS combination drives geomagnetic storms that…Read more on Radiation belt electron flux variability during three CIR-driven geomagnetic storms
1 January, 2009 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
The flow of ice streams, which account for most discharge from large ice sheets, is controlled by processes operating at the ice stream bed. Data from modern ice stream beds…1 January, 2009
It has long been recognized that biological activity has a large influence on biogeochemical cycles in the ocean. However, the recognition that the ecosystem composition may also be significant is…1 January, 2009 by Philip Leat, Teal Riley
New whole rock Rb-Sr and zircon U-Pb geochronological data and Sm-Nd isotopic data are presented from the central magmatic arc domain of the Antarctic Peninsula in the area of northwest…1 January, 2009
The island of South Georgia is located at the southern extreme of the South Atlantic Ocean, on the edge of the Southern Ocean that surrounds Antarctica. Intensive commercial whaling at…Read more on Molecular species identification of historical whale remains from South Georgia
1 January, 2009 by Hua Lu
This paper provides some insights on the quasi-biennial oscillation (QBO) modulated 11-year solar cycle (11-yr SC) signals in Northern Hemisphere (NH) winter temperature and zonal wind. Daily ERA-40 Reanalysis and…1 January, 2009
The Mid-Pliocene (ca 3 Myr ago) was a relatively warm period, with increased atmospheric CO2 relative to pre-industrial. It has therefore been highlighted as a possible palaeo-analogue for the future.…Read more on The Arctic cryosphere in the Mid-Pliocene and the future
1 January, 2009 by Richard Horne
High geomagnetic activity occurs continuously during high-speed solar wind streams, and fluxes of relativistic electrons observed at geosynchronous orbit enhance significantly. High-speed streams are preceded by solar wind compression regions,…