Found 13254 items
1 January, 2010
The longitudinal variability of the semidiurnal tide in the Antarctic upper mesosphere is investigated by comparison of observations from two radars at approximately opposite sides of Antarctica. Under the assumption…Read more on A new perspective on the longitudinal variability of the semidiurnal tide
1 January, 2010 by Oliver Marsh
Twelve years of horizontal wind data from the Scott Base MF radar and the Halley SuperDARN radar recorded between January 1996 and December 2007 are analysed to study the interannual…1 January, 2010 by Claire Waluda, Jaume Forcada, Philip Trathan, Simeon Hill
The purpose of ecosystem monitoring programs is to indicate the state of ecosystems and whether they have been impacted by activities such as fishing. This paper discusses a range of…Read more on Using ecosystem monitoring data to detect impacts
1 January, 2010 by Claus-Dieter Hillenbrand, Robert Larter
A major trough ("Belgica Trough") eroded by a palaeo-ice stream crosses the continental shelf of the southern Bellingshausen Sea (West Antarctica) and is associated with a trough mouth fan ("Belgica…1 January, 2010 by Claus-Dieter Hillenbrand, James Smith, Robert Larter
Reliable dating of glaciomarine sediments deposited on the Antarctic shelf since the Last Glacial Maximum (LGM) is challenging because of the rarity of calcareous (micro-) fossils and the recycling of…1 January, 2010 by Chester Sands, Dominic Hodgson, Peter Convey, Sandra McInnes, Sandra McInnes
Very little is known about the higher latitude inland biology of continental Antarctica. In this paper we describe the limnology and biology of the Dufek Massif, using a range of…Read more on The limnology and biology of the Dufek Massif, Transantarctic Mountains 82° South
1 January, 2010 by Dominic Hodgson, Louise Sime
The Southern Hemisphere westerly winds affect the exchange of carbon dioxide between the ocean and atmosphere. Climate reconstructions from the southern mid-latitudes may reveal variability in the strength and position…1 January, 2010 by David Pearce
Glacier surfaces support unique microbial food webs dominated by organic and inorganic debris called 'cryoconite'. Observations from Longyearbreen, Spitsbergen, show how these aggregate particles can develop an internal structure following…1 January, 2010 by Kevin Newsham
Solute yields, laboratory dissolution data and both chemical and isotopic markers of rock weathering reactions are used to characterise the biogeochemistry of glacial meltwaters draining a maritime Antarctic glacier. We…1 January, 2010 by Guy Hillyard, Lloyd Peck, Melody Clark
The extent to which genetic divergence can occur in the absence of physical barriers to gene flow is currently one of the most controversial topics in evolutionary biology, with implications…1 January, 2010 by Jaume Forcada
Although heterozygosity-fitness correlations (HFCs) are widely reported in the literature, most studies use too few markers to allow the proximate mechanisms to be convincingly resolved. Two competing hypotheses have been…1 January, 2010 by Jaume Forcada, Philip Trathan
Most studies of heterozygosity-fitness correlations (HFCs) in natural populations relate to fitness traits expressed early in life, whereas traits that are often more difficult to measure such as longevity and…1 January, 2010 by Rachel Cavanagh
Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species…Read more on The impact of conservation on the status of the world’s vertebrates
1 January, 2010 by Eric Wolff
Ice core evidence indicates that even though atmospheric CO2 concentrations did not exceed 300 ppm at any point during the last 800 000 years, East Antarctica was at least 3–4…1 January, 2010 by Paul Holland
Greenland is losing ice through glaciers that flow into deep fjords. New observations highlight the important fjord processes that supply warm ocean waters to the melting glaciers, and thereby affect…1 January, 2010 by Kevin Hughes, Peter Convey, Rolf Maslen
Antarctic terrestrial ecosystems currently include very few non-native species, due to the continent’s extreme isolation from other landmasses. However, the indigenous biota is vulnerable to human-mediated introductions of non-native species.…1 January, 2010 by Kevin Hughes
Under the Antarctic Treaty System, environmental monitoring is a legal obligation for signatory nations and an essential tool for managers attempting to minimize local human impacts, but is it given…Read more on How committed are we to monitoring human impacts in Antarctica?
1 January, 2010 by Kevin Hughes, Peter Convey
Invasions by non-indigenous species are amongst the greatest threats to global biodiversity, causing substantial disruption to, and sometimes local extinction of, individual species and community assemblages which, in turn, can…1 January, 2010 by Kevin Hughes
Antarctic ecosystems are at risk from the introduction of invasive species. The first step in the process of invasion is the transportation of alien species to Antarctic in a viable…Read more on Impact of anthropogenic transportation to Antarctica on alien seed viability
1 January, 2010 by Kevin Hughes, Roger Worland
The introduction of invasive species is one of the greatest threats to Earth’s biodiversity, as they can reduce native biodiversity and alter ecosystem structure and function. Currently, the only two…1 January, 2010 by David Vaughan
A narrow bridge of floating ice that connected the Wilkins Ice Shelf, Antarctica, to two confining islands eventually collapsed in early April 2009. In the month preceding the collapse, we…Read more on Deformation and failure of the ice bridge on the Wilkins Ice Shelf, Antarctica
1 January, 2010 by Katrin Linse
The shelled pteropod (sea butterfly) Limacina helicina is currently recognised as a species complex comprising two sub-species and at least five "forma". However, at the species level it is considered…1 January, 2010
As part of the open access publishing movement, Research Councils UK has mandated that the outputs of all Research Council funded research must be deposited in an institutional or subject-based…Read more on NORA: An Open Window to British Antarctic Research
1 January, 2010
Solar Radiation Management (SRM) Geoengineering may ameliorate many consequences of global warming but also has the potential to drive regional climates outside the envelope of greenhouse-gas induced warming, creating 'novel'…Read more on Assessing the regional disparities in geoengineering impacts
1 January, 2010 by Jennifer Jackson
At present, there are 15 species of baleen whales that belong to the monophyletic suborder Mysticeti. The family-level designations of Balaenidae (right and bowhead whales) and Neobalaenidae (pygmy right whales)…1 January, 2010 by Ed King
We modelled the flow of the Larsen C and northernmost Larsen D ice shelves, Antarctic Peninsula, using a model of continuum mechanics of ice flow, and applied a fracture criterion…Read more on Present stability of the Larsen C ice shelf, Antarctic Peninsula
1 January, 2010
Several papers have recently invoked Joule heating in the stratosphere, generated from electric currents induced by solar wind interactions with Earth, as possibly playing a significant role in warming the…Read more on The ineffectiveness of Joule heating in the stratosphere
1 January, 2010 by Adrian Jenkins, Hugh Corr, Keith Nicholls
Parameterizations of turbulent transfer through the oceanic boundary layer beneath an ice shelf are tested using direct measurements of basal ablation. Observations were made in the southwestern part of Ronne…Read more on Observation and parameterization of ablation at the base of Ronne Ice Shelf, Antarctica
1 January, 2010 by Anna Jones, Eric Wolff, Gareth Marshall, Howard Roscoe, Neil Brough, Steve Colwell
The majority of tropospheric ozone depletion event (ODE) studies have focussed on time-series measurements, with comparatively few studies of the vertical component. Those that exist have almost exclusively used free-flying…1 January, 2010 by Hugh Venables
The effect of sea ice melt on the carbonate chemistry of surface waters in the Weddell-Scotia Confluence, Southern Ocean, was investigated during January 2008. Contrasting concentrations of dissolved inorganic carbon…Read more on Rapid changes in surface water carbonate chemistry during Antarctic sea ice melt
1 January, 2010 by Fausto Ferraccioli, Hugh Corr, Tom Jordan
Subglacial outburst floods at the margins of the Antarctic and Laurentide Ice Sheets have been linked to changes in global ocean circulation and climate. The impact of palaeo-hydrological systems beneath…1 January, 2010 by David Vaughan, Fausto Ferraccioli, Hugh Corr, Tom Jordan
The West Antarctic Rift System provides critical geological boundary conditions for the overlying West Antarctic Ice Sheet. Previous geophysical surveys have traced the West Antarctic Rift System and addressed the…1 January, 2010 by Michael Meredith
Recent studies suggest that the variability in Antarctic Bottom Water (AABW) properties in the Scotia Sea on time scales up to decadal may be linked to changes in the baroclinicity…Read more on Wind-controlled export of Antarctic Bottom Water from the Weddell Sea
1 January, 2010 by Andrew Orr
The progress achieved since 2005 in simulating today's climate with the European Centre for Medium-Range Weather Forecasts (ECMWF) model through improved physical parametrizations is described. Results are based on climate…Read more on The ECMWF model climate: Recent progress through improved physical parametrizations
1 January, 2010 by Eric Wolff
Sulfate (SO42-) and ammonium (NH4+) flux records over the last 150,000 years from both Antarctic EPICA ice cores (European Project for Ice Coring in Antarctica) are presented. The ice core…1 January, 2010 by Andy Smith
Modulation of the flow of Rutford Ice Stream, Antarctica, has been reported previously at semi-diurnal, diurnal, fortnightly and semi-annual periods. A model that includes non-linear response to tidal forcing has…1 January, 2010 by Geraint Tarling, Sophie Fielding
We studied the relationship between the proximity of land and the distribution and swarming characteristics of Antarctic krill across the Scotia Sea in January and February 2003. Krill swarms identified…1 January, 2010 by Peter Ward
During the austral summer of 2008, we carried out a high resolution survey of the microplankton communities along a south to north transect covering a range of environments across the…1 January, 2010 by Peter Convey
We studied the development of the Antarctic herb tundra vegetation formation in relation to the history of deglaciation across a range of habitats near H. Arctowski Research Station (King George…1 January, 2010 by David Barnes
A bipolar distribution is one in which a taxon occurs at high northern and southern latitudes but is absent in the latitudes between. In spite of the large distance between…1 January, 2010 by Howard Roscoe
The passive tracer method is used to estimate ozone loss from ground-based measurements in the Antarctic. A sensitivity study shows that the ozone depletion can be estimated within an accuracy…Read more on Estimation of Antarctic ozone loss from ground-based total column measurements
1 January, 2010 by Thomas Lachlan-Cope
Sensitivity studies with global climate models show that, by their influence on the radiation balance, Antarctic clouds play a major role in the climate system, both directly at high southern…1 January, 2010
To determine the potential of Antarctic bivalve shells as biomonitors for environmental and climatic variations in polar marine areas, we developed a growth model for juvenile Adamussium colbecki Smith, 1902…1 January, 2010 by Robert Larter
Amundsen Sea Embayment: Tectonic and Climatic Evolution; Granada, Spain, 9 September 2009; Geoscientists working on the Amundsen Sea Embayment (ASE) of West Antarctica met at a workshop during the First…Read more on Improving constraints on paleo-ice sheets in the Amundsen Sea Embayment
1 January, 2010
Only about 45% of the total CO2 emitted from fossil fuel burning and land use change stayed in the atmosphere on average during the past few decades. The remaining CO2…1 January, 2010
The international political commitment to limit global warming to 2 °C urgently requires the stabilisation of radiative forcing from carbon dioxide (CO2) and other greenhouse gases (GHG) in the atmosphere.…Read more on An International Carbon Office to assist policy-based science
1 January, 2010
About one quarter of the CO2 emitted to the atmosphere by human activities is absorbed annually by the ocean. All the processes that influence the oceanic uptake of CO2 are…Read more on Impact of climate change and variability on the global oceanic sink of CO2
1 January, 2010 by Alexander Tate, Philip Leat
New multibeam (swath) bathymetric sonar data acquired using an EM120 system on the RRS James Clark Ross, supplemented by sub-bottom profiling, reveals the underwater morphology of a not, vert, similar…1 January, 2010 by Hilmar Gudmundsson
The advance of a glacier over a deforming sediment layer is analysed numerically. We treat this problem as a contact problem involving two slowly-deforming viscous bodies. The surface evolution of…Read more on A numerical study of glacier advance over deforming till
1 January, 2010 by Melody Clark
The gilthead sea bream. Sparus auratus, and the European sea bass, Dicentrarchus labrax, are two of the most important marine species cultivated in Southern Europe. This study aimed at increasing…1 January, 2010
Quantifying the equilibrium response of global temperatures to an increase in atmospheric carbon dioxide concentrations is one of the cornerstones of climate research. Components of the Earth's climate system that…Read more on Earth system sensitivity inferred from Pliocene modelling and data
1 January, 2010
Changes in ocean circulation have been proposed as a trigger mechanism for the large coupled climate and carbon cycle perturbations at the Paleocene-Eocene Thermal Maximum (PETM, ca. 55 Ma). An…1 January, 2010 by Lloyd Peck, Simon Morley
Habitat temperature and mitochondrial volume density (Vv(mt,mf)) are negatively correlated in fishes, while seasonal acclimatization may increase Vv(mt,mf) or the surface density of the mitochondrial cristae (Sv(im,mt)). The effect of…1 January, 2010 by Lloyd Peck, Simon Morley
Temperature and mitochondrial plasticity are well studied in fishes, but little is known about this relationship in invertebrates. The effects of habitat temperature on mitochondrial ultrastructure were examined in three…Read more on Ultrastructure of pedal muscle as a function of temperature in nacellid limpets
1 January, 2010 by Philip Leat
Geochemical provinciality of the Karoo continental flood basalt (CFB) province is complicated by the great diversity of magma types. Our geochemical and Nd and Sr isotopic data indicate derivation of…1 January, 2010
Polar ice is known to be one of the most anisotropic natural materials. For a given fabric the polycrystal viscous response is strongly dependent on the actual state of stress…1 January, 2010 by Janet Silk, Richard Phillips, Vsevolod Afanasyev
This is the first comprehensive study of at-sea activity patterns of albatrosses during the nonbreeding period, based on data from combination geolocator–immersion loggers deployed on the wandering albatross Diomedea exulans,…Read more on Free as a bird? Activity patterns of albatrosses during the nonbreeding period
1 January, 2010 by Liz Thomas
Desert dust perturbs climate by directly and indirectly interacting with incoming solar and outgoing long wave radiation, thereby changing precipitation and temperature, in addition to modifying ocean and land biogeochemistry.…Read more on Observed 20th century desert dust variability: impact on climate and biogeochemistry
1 January, 2010
Terrestrial and oceanic ecosystem components of the Earth System models (ESMs) are key to predict the future behavior of the global carbon cycle. Ocean ecosystem models represent low complexity compared…1 January, 2010 by Philip Leat
The Grunehogna Craton (GC, East Antarctica) is interpreted as part of the Archaean Kaapvaal Craton of southern Africa prior to Gondwana breakup. The basement of the GC is exposed only…1 January, 2010 by Gareth Marshall
The deuterium excess of polar ice cores documents past changes in evaporation conditions and moisture origin. New data obtained from the European Project for Ice Coring in Antarctica Dome C…Read more on An abrupt change of Antarctic moisture origin at the end of Termination II
1 January, 2010
Climate models show strong links between Antarctic and global temperature both in future and in glacial climate simulations. Past Antarctic temperatures can be estimated from measurements of water stable isotopes…Read more on EPICA Dome C record of glacial and interglacial intensities
1 January, 2010 by Peter Convey
Three mineral soil and four ornithogenic soil sites were sampled during summer 2006 at Cierva Point (Antarctic Peninsula) to study their bacterial, microalgal and faunal communities in relation to abiotic…1 January, 2010
A multidisciplinary provenance study, including in situ U-Pb dating of detrital titanite, was undertaken on the enigmatic low-grade metasediments of the Colonsay Group, SW Scotland to determine their source and…1 January, 2010
Metasediments of the early Dalradian Grampian Group (Erris Group) and probable equivalents (Inishkea Division) structurally overlie Palaeoproterozoic to Neoproterozoic Annagh Gneiss Complex orthogneisses in NW Mayo, Ireland. Sm-Nd isotopic data…1 January, 2010
Whole-rock Sm-Nd model ages of 1601 Ma (lower Laggan Formation) and 1674 Ma (upper Blackrock Formation) suggest a late Palaeoproterozoic, early Mesoproterozoic source for the rnetasediments of the Bowmore Sandstone…Read more on Dalradian Grampian Group affinity for the Bowmore Sandstone Group, Islay, SW Scotland
1 January, 2010 by Peter Convey
Spatial and temporal environmental variation in terrestrial Antarctic ecosystems are known to impact species strongly at a local scale, but the ways in which organisms respond (e.g. physiologically, behaviourally) to…1 January, 2010 by Peter Convey
Measurement of metabolic rates (made at 10A degrees C) of individuals of the springtail Cryptopygus antarcticus travei from six geographically distinct populations on sub-Antarctic Marion Island were combined with mitochondrial…1 January, 2010 by Peter Convey
We examined the genetic structure among populations and regions for the springtails Cryptopygus antarcticus antarcticus and Gomphiocephalus hodgsoni (Collembola) to identify potential historical refugia and subsequent colonization routes, and to…1 January, 2010 by Sandra McInnes, Sandra McInnes
Echiniscus corrugicaudatus sp. nov., (Heterotardigrada; Echiniscidae) was found in the limited vegetation from the inland nunataks of Ellsworth Land, West Antarctica. The tardigrade fauna of this a rarely explored region…1 January, 2010 by Andrew Clarke, Deb Shoosmith, Terri Souster, Hugh Venables, Michael Meredith, Terri Souster
In recent decades, the west Antarctic Peninsula (WAP) has warmed more rapidly than anywhere else in the Southern Hemisphere. Associated with this, there has been a marked shortening of the…1 January, 2010 by Eric Wolff
As the planet cooled from peak warmth in the early Cenozoic, extensive Northern Hemisphere ice sheets developed by 2.6 Ma ago, leading to changes in the circulation of both the…Read more on Temperature and precipitation history of the Arctic
1 January, 2010 by Vsevolod Afanasyev
With the development of archival light level geolocators weighing only 1 g, their deployment on medium size waders is now possible. Trials showed that attachment via leg flag rather than…1 January, 2010 by Tracy Moffat-Griffin
An imaging riometer uses the absorption of cosmic radio noise as a means of measuring electron density enhancements in the D region of the ionosphere. It employs a ground-based phased…Read more on Calibrating an imaging riometer: determination of the true beam azimuth angle position
1 January, 2010 by Howard Roscoe
Measurements of NO and NO2 were made at a surface site (55.28 degrees N, 77.77 degrees W) near Kuujjuarapik, Canada during February and March 2008. NOx mixing ratios ranged from…1 January, 2010 by Philip Trathan
Diving animals have to counter both drag and buoyancy when moving through the water column. The magnitude of these forces depends upon an animal's swim speed and current depth. Feet,…Read more on Optimal stroke frequency during diving activity in seabirds
1 January, 2010 by Lloyd Peck, Melody Clark, Simon Morley
To fully understand how species distributions will respond to changing environments it is essential to understand the mechanisms underlying variation in animal performance and the relative importance of different ecological…1 January, 2010 by David Barnes, Huw Griffiths, Lloyd Peck, Simon Morley
Antarctic marine invertebrates from the Western Antarctic Peninsula (WAP) are generally stenothermal, with three-month survival and activity limits above the average maximum summer seawater temperature (1.0 degrees C) of 1-6…1 January, 2010 by Iain Staniland
In order to investigate the extent to which Perfluorinated Contaminants (PFCs) have permeated the Southern Ocean food web to date, a range of Antarctic, sub-Antarctic and Antarctic-migratory biota were analysed…1 January, 2010 by Jaume Forcada
A major challenge in ecology is to understand the impact of increased environmental variability on populations and ecosystems. To maximize their fitness in a variable environment, life history theory states…Read more on Bet-hedging response to environmental variability, an intraspecific comparison
1 January, 2010 by Kevin Newsham
The biology and ecology of Cephaloziella varians, the most widespread and abundant liverwort in Antarctica, are reviewed. A description of the species is given, together with information on its geographical…Read more on The biology and ecology of the liverwort Cephaloziella varians in Antarctica
1 January, 2010 by Kevin Newsham
The leafy liverwort Lophozia excisa, which is colonised by basidiomycete fungi in other biomes and which evidence suggests may be colonised by mycorrhizal fungi in Antarctica, was sampled from L,onie…1 January, 2010 by David Pearce, Kevin Newsham
Bacterial community composition was determined by culture-independent PCR-based methods in two soils differing markedly in their water, C, N and P contents sampled from Mars Oasis on Alexander Island, western…1 January, 2010 by Ed King, Richard Hindmarsh, Robert Larter, Richard Hindmarsh
The submarine glacial geomorphology and sedimentology of the cross-shelf troughs and the adjacent continental slope around the Antarctic Peninsula and West Antarctica have been the focus of a series of…1 January, 2010 by David Barnes, Lloyd Peck, Simon Morley
Pronounced seasonality in photoperiod and phytoplankton availability drives key physiological processes in many Antarctic primary consumers. To test the hypothesis that carnivores would be less markedly affected by environmental seasonality…Read more on Seasonal physiology and ecology of Antarctic marine benthos predators and scavengers
1 January, 2010 by Carlos Martin Garcia
Calving from tidewater glaciers and ice shelves accounts for around half the mass loss from both polar ice sheets, yet the process is not well represented in prognostic models of…1 January, 2010 by Adrian Jenkins, Deb Shoosmith
We demonstrate the first use of marine mammal dive-depth data to improve maps of bathymetry in poorly sampled regions of the continental shelf. A group of 57 instrumented elephant seals…Read more on Seals map bathymetry of the Antarctic continental shelf
1 January, 2010 by Anna Jones, David Pearce, Kevin Hughes, Thomas Lachlan-Cope
A study of air-borne microbial biodiversity over an isolated scientific research station on an ice-shelf in continental Antarctica was undertaken to establish the potential source of microbial colonists. The study…Read more on Biodiversity of air-borne microorganisms at Halley station Antarctica
1 January, 2010 by Daniel Peavoy
We present statistical methods to determine climate regimes for the last glacial period using three temperature proxy records from Greenland: measurements of δ18O from the Greenland Ice Sheet Project 2…1 January, 2010 by Andrew Clarke, Andrew Fleming, David Barnes, Lloyd Peck
Feedbacks on climate change so far identified are predominantly positive, enhancing the rate of change. Loss of sea-ice, increase in desert areas, water vapour increase, loss of tropical rain forest…Read more on Negative feedback in the cold: ice retreat produces new carbon sinks in Antarctica
1 January, 2010 by Lloyd Peck
Geographical variations in animal characters are one of the main subjects for study in macroecology. Variation with latitude has received special interest. Articulated brachiopods are possibly the commonest macrofossil with…Read more on Variation in size of living articulated brachiopods with latitude and depth
1 January, 2010 by Lloyd Peck, Melody Clark, Simon Morley
Animals can respond to temperature change by the following means: using physiological flexibility (including acclimation); or adapting; or migrating, with acclimation proposed as the major mechanism dictating prospects for survival…Read more on Poor acclimation capacities in Antarctic marine ectotherms
1 January, 2010 by Victoria Peck
To date, no conclusive evidence has been identified for intermediate or deep water cooling associated with the > 1 parts per thousand benthic delta O-18 increase at the Eocene-Oligocene transition…1 January, 2010 by Richard Phillips
The United Nations, under the auspices of the Convention on Biological Diversity (CBD) has proclaimed 2010 as the International Year of Biodiversity. This has led to numerous initiatives to highlight…Read more on Eradications of invasive mammals from islands: why, where, how and what next?