Found 14049 items
25 March, 2009
Source regions for the westward propagating zonal wavenumber one and three components of the semidiurnal tide observed in the summer mesosphere and lower thermosphere over Antarctica are identified by correlating…Read more on Source regions for Antarctic MLT non-migrating semidiurnal tides
24 March, 2009 by Kevin Newsham
Understanding and accurately predicting the fate of carbon and nitrogen in the terrestrial biosphere remains a central goal in ecosystem science. Amino acids represent a key pool of C and…Read more on Soil organic nitrogen mineralization across a global latitudinal gradient
3 March, 2009 by Povl Abrahamsen
Microstructure and hydrographic observations, during September 2007 in the boundary current on the East Siberian continental slope, document upper ocean stratification and along-stream water mass changes. A thin warm surface…Read more on Vertical mixing at intermediate depths in the Arctic boundary current
25 February, 2009 by Gareth Chisham, Mervyn Freeman
In this paper we determine the probability of substorm onset as a function of open magnetic flux in the magnetosphere by comparing the occurrence distribution of open flux observed at…11 February, 2009
We perform two superposed epoch analyses of the auroral evolution during substorms using the FUV instrument on the Imager for Magnetopause-to-Aurora Global Explorer ( IMAGE) spacecraft. The larger of the…6 February, 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…3 February, 2009 by Howard Roscoe
A new climatology of stratospheric BrO profiles based on a parameterization using dynamical and chemical indicators has been developed, with the aim to apply it to the retrieval of tropospheric…1 January, 2009 by Richard Phillips
Seabirds are often advocated as biomonitors for marine contaminants such as mercury (Hg). However, contaminant levels can vary widely depending on among-individual and among-species variation in foraging preferences and physiology,…1 January, 2009 by Richard Phillips
The diet of brown skuas (Catharacta antarctica lonnbergi) on Bird Island, South Georgia was assessed using a combination of stable isotope analysis (SIA) and mixing model techniques. We found evidence…1 January, 2009
During the Middle Pliocene, the Earth experienced greater global warmth compared with today, coupled with higher atmospheric CO2 concentrations. To determine the extent to which the Middle Pliocene can be…1 January, 2009 by Gareth Chisham, Mervyn Freeman
We present an analysis of 8 years of meridional line-of-sight ionospheric plasma velocity measurements from the Halley SuperDARN radar which investigates the effect of the interplanetary magnetic field (IMF) clock…Read more on IMF clock angle control of multifractality in ionospheric velocity fluctuations
1 January, 2009
The Indo-Pacific Warm Pool (IPWP) is thought to play a key role in the propagation and amplification of climate changes through its influence on the global distribution of heat and…1 January, 2009 by Philip Trathan
We report the characterization of 25 microsatellite loci isolated from the macaroni penguin (Eudyptes chrysolophus). Thirteen loci were arranged into four multiplex sets for future genetic studies of macaroni penguin…1 January, 2009
The empirical dependence of turbulence Prandtl number (Pr) on gradient Richardson number (Ri) is presented, derived so as to avoid the effects of self-correlation from common variables. Linear power relationships…1 January, 2009
Despite much research on Euphausia superba, estimates of their total biomass and production are still very uncertain. Recently, circumpolar krill databases, combined with growth models and revisions in acoustics have…Read more on A re-appraisal of the total biomass and annual production of Antarctic krill
1 January, 2009
To evaluate and extend the record of decadal climate variability, we present a synthesis of 23 coral oxygen isotope records from the tropical Indo-Pacific that extends back to A. D.…Read more on Intensified decadal variability in tropical climate during the late 19th century
1 January, 2009 by Martin Collins
A severe scarcity of life history and population data for deep-water fishes is a major impediment to successful fisheries management. Long-term data for non-target species and those living deeper than…1 January, 2009 by Eric Wolff
Quaternary Climate: From Pole to Pole—EPICA Open Science Conference; Venice, Italy, 10–13 November 2008; The European Project for Ice Coring in Antarctica (EPICA) has provided unique paleoclimatic data and is…Read more on Toward a better understanding of climate of the past million years
1 January, 2009
The asynchronous relationship between millennial-scale temperature changes over Greenland and Antarctica during the last glacial period has led to the notion of a bipolar seesaw which acts to redistribute heat…Read more on Interhemispheric Atlantic seesaw response during the last deglaciation
1 January, 2009 by David Barnes
One of the most ubiquitous and long-lasting recent changes to the surface of our planet is the accumulation and fragmentation of plastics. Within just a few decades since mass production…Read more on Accumulation and fragmentation of plastic debris in global environments
1 January, 2009 by David Barnes, Huw Griffiths
Toleration, adaptation, migration or extinction are the options for species making up Southern Ocean (SO) shelf biodiversity, in response to accelerating change (e.g. warming), Physiological evidence suggests few organisms may…1 January, 2009 by David Barnes, Huw Griffiths, Katrin Linse
We ask how biodiverse is a polar archipelago; how this faunal richness is spread across marine, intertidal, freshwater, terrestrial and parasitic realms; and how fast species are accumulated with increased…1 January, 2009 by Andy Smith, David Vaughan, Keith Nicholls
The Antarctic Peninsula has warmed faster than the global average rate of warming during the last century. Due to limited availability of long term meteorological records, the geographical extent of…Read more on Rapid recent warming on Rutford Ice Stream, West Antarctica, from borehole thermometry
1 January, 2009 by Mark Belchier, Peter Fretwell
A new South Georgia Bathymetric Dataset (SGDB) was compiled from a variety of primary sources including multi-beam swath bathymetry. Sea floor area (km(2)1 January, 2009 by Dominic Hodgson, Claus-Dieter Hillenbrand, James Smith, Robert Larter, Stephen Roberts
The Antarctic Peninsula is one of the three fastest warming regions on Earth. Here we review Holocene proxy records of marine and terrestrial palaeoclimate in the region, and discuss possible…Read more on Mechanisms of Holocene palaeoenvironmental change in the Antarctic Peninsula region
1 January, 2009 by Dominic Hodgson
Reconstructing the former dimensions and deglacial history of the Antarctic Ice Sheet along with Antarctic paleoclimate is important for understanding forcing mechanisms of ice sheet change. Here, we review briefly…Read more on Antarctic ice sheet and climate history since the Last Glacial Maximum
1 January, 2009
Glaciated landscapes consist of complex assemblages of landforms resulting from ice flow dynamic regimes and ice-sheet history, superimposed over, and in turn modifying, preglacial topography, lithology and geological structure. insights…1 January, 2009 by Hilary Blagbrough
The British Antarctic Survey is the custodian of more than 57,000 Antarctic fossils, of which some 2,500 are Type & Figured specimens. In addition to these, the geological collections include…Read more on In from the cold: an overview of the British Antarctic Survey fossil collections
1 January, 2009 by William Block
Antarctic fellfields present organisms with a heterogeneous habitat characterised by a wide variety of environmental stresses. These include low temperatures, limited moisture availability, frequent and often rapid freeze-thaw and hydration-dehydration…Read more on Strategies of survival and resource exploitation in the Antarctic fellfield ecosystem
1 January, 2009
It has been suggested that, during the Pliocene (ca 5–1.8Ma), an El Niño state existed as a permanent rather than an intermittent feature; that is, the tropical Pacific Ocean was…Read more on El Niño–Southern Oscillation, Pliocene climate and equifinality
1 January, 2009 by Pierre Dutrieux
A combination of 15N2 labeling, Tyramide Signal Amplification–Fluorescent in Situ Hybridization (TSA-FISH) assay, and chemical analyses were performed along a trophic gradient (8000 km) in the equatorial Pacific. Nitrogen fixation…1 January, 2009 by Nigel Meredith
A brief overview is given of the history of plasmaspheric hiss research, particularly in the context of the recent work by Bortnik et al. (2008) indicating that chorus could be…Read more on Plasmaspheric hiss overview and relation to chorus
1 January, 2009 by Philip Trathan
Although penguins are key marine predators from the Southern Ocean, their migratory behaviour during the inter-nesting period remains widely unknown. Here, we report for the first time, to our knowledge,…1 January, 2009 by Andrew Clarke, Lloyd Peck
Most marine benthic macroinvertebrate species reproduce via a larval phase but attempts to explain the occurrence of different larval strategies (feeding or non-feeding, pelagic or benthic) in different habitats have…1 January, 2009 by Thomas Bracegirdle
The dynamics of a polar low are examined using a piecewise potential vorticity (PV) inversion method. In previous studies of this and other polar lows, structural evolution has been described…Read more on The dynamics of a polar low assessed using potential vorticity inversion
1 January, 2009 by Katrin Linse
The aim of this study is to compare the depth distributions of four major Southern Ocean macrobenthic epi- and infaunal taxa, the Bivalvia, Gastropoda, Isopoda, and Polychaeta, from subtidal to…1 January, 2009 by Kevin Newsham
PCR amplification of ITS1-5.8S-ITS2 regions of rDNA followed by cloning was used to determine the fungi present in soil from three sites at Mars Oasis in the southern maritime Antarctic.…Read more on Soil fungal community composition at Mars Oasis, a southern maritime Antarctic site
1 January, 2009 by Markus Frey
An analysis of 96 snow pit and ice cores distributed over the Greenland ice sheet is used to determine the main drivers of variability in the preserved records of nitrate…1 January, 2009 by Lloyd Peck
Extrinsic neural and humoral influences on heart rate (fH) and ventilation frequency (fV) were examined following varying periods of post-surgical recovery in eight related Antarctic fish species inhabiting an array…Read more on Heart rate and ventilation in Antarctic fishes are largely determined by ecotype
1 January, 2009 by Richard Phillips
This is the first study using geolocators (global location sensing, GLS) to track the movements of a pelagic tropical seabird. We used GLS to describe at-sea distribution and activity patterns…1 January, 2009
Similarity analysis is used to identify the control parameter RA for the subset of avalanching systems that can exhibit self-organized criticality SOC. This parameter expresses the ratio of driving to…Read more on Macroscopic control parameter for avalanche models of bursty transport
1 January, 2009
The paradigm of self-organized criticality (SOC) has found application in understanding scaling and bursty transport in driven, dissipative plasmas. SOC is, however, a limiting process that occurs as the ratio…Read more on Avalanching systems under intermediate driving rate
1 January, 2009 by Richard Horne
A three dimensional ray tracing of whistler-mode chorus is performed in a realistic magnetosphere using the HOTRAY code. A variety of important propagation characteristics are revealed associated with azimuthal density…1 January, 2009 by Richard Horne
The HOTRAY code is used to evaluate the path integrated gain of electromagnetic ion cyclotron (EMIC) waves as a function of frequency in two propagation bands above the O+ and…1 January, 2009 by Michael Dunn, Peter Convey
Soil bacterial diversity at environmentally distinct locations on Signy Island, South Orkney Islands was examined using the denaturing gradient gel profiling approach. A range of chemical variables in soils at…1 January, 2009 by Lloyd Peck, Melody Clark
The ability to understand and predict the effects of environmental stress on biodiversity is becoming increasingly important in our changing environment. Antarctic marine species are some of the most stenothermal…1 January, 2009 by Lloyd Peck, Melody Clark
The Antarctic limpet, Nacella concinna, exhibits the classical heat shock response, with up-regulation of duplicated forms of the inducible heat shock protein 70 (HSP70) gene in response to experimental manipulation…1 January, 2009 by Guy Hillyard, Michael Thorne, Roger Worland, Melody Clark
Background: Insects provide tractable models for enhancing our understanding of the physiological and cellular processes that enable survival at extreme low temperatures. They possess three main strategies to survive the…1 January, 2009 by Mark Clilverd
We analyze in detail the February 2004 Global Ozone Monitoring by Occultation of Stars (GOMOS) NO2 observations in the northern polar latitudes during the springtime descent of NOx from the…1 January, 2009 by Mark Clilverd, Neil Cobbett
[1] The Antarctic-Arctic Radiation-belt (Dynamic) Deposition-VLF Atmospheric Research Konsortium (AARDDVARK) provides a network of continuous long-range observations of the lower ionosphere in the polar regions. Our ultimate aim is to…1 January, 2009
Rothera research station is a British Antarctic Survey (BAS) base on the Antarctic Peninsula that is operational year round. During the 8-month winter the 20 people living there are physically…1 January, 2009 by Peter Convey
As we draw towards the end of the massive effort that has been the International Polar Year (IPY), it is opportune to consider what impact it has had on Antarctic…Read more on Antarctic biology, the International Polar Year, and beyond
1 January, 2009 by Dominic Hodgson, John Turner, Peter Convey
The Antarctic climate system varies on timescales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from…Read more on Review. Antarctic climate change and the environment
1 January, 2009 by Peter Convey
Sub-Antarctic islands share many similarities in their history of human interaction and impacts before the mid-twentieth century. Large impacts on land were associated with marine exploitation industries of sealing and…1 January, 2009 by Andrew Clarke, Dominic Hodgson, David Barnes, Claus-Dieter Hillenbrand, Peter Convey
The evolutionary and biogeographic history of the contemporary Antarctic terrestrial and marine biotas reveals many components of ancient origin. For large elements of the terrestrial biota, long-term isolation over timescales…Read more on Exploring biological constraints on the glacial history of Antarctica
1 January, 2009 by Howard Roscoe
NO2 measurements during 1990-2007, obtained from a zenith-sky spectrometer in the Antarctic, are analysed to determine the long-term changes in NO2. An atmospheric photochemical box model and a radiative transfer…1 January, 2009 by Robert Larter
Seismic stratigraphic studies and scientific drilling of the Antarctic continental margin have yielded clues to the evolution of Cenozoic climates, depositional paleoenvironments and paleoceanographic conditions. This paper draws on studies…1 January, 2009
Subglacially erupted Neogene basaltic hyaloclastites in lava-fed deltas in Antarctica were found to contain putative endolithic microborings preserved in fresh glass along hydrous alteration boundaries. The location and existence over…1 January, 2009 by Geraint Tarling, Sally Thorpe
We model a summer snapshot of the behavior of Antarctic krill (Euphausia superba) during advection across the Scotia Sea. Individual krill respond to a changing landscape of predation risk and…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
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 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,…