Showing 13455 items
1 January, 2012 by Michael Thorne, Melody Clark
Several organisms display dormancy and developmental arrest at embryonic stages. Long-term survival in the dormant form is usually associated with desiccation, orthodox plant seeds and Artemia cysts being well documented…Read more on Long-Term Survival of Hydrated Resting Eggs from Brachionus plicatilis
1 January, 2012 by Terri Souster, Melody Clark, Terri Souster
Regeneration of arms in brittle stars is thought to proceed slowly in low temperature environments. Here a survey of natural arm damage and arm regeneration rates is documented in the…1 January, 2012 by Andrew Clarke, David Barnes, Eugene Murphy, John King, Lloyd Peck, Michael Meredith, Nadine Johnston, Thomas Bracegirdle
The Antarctic Peninsula is one of three areas of the globe currently experiencing rapid regional climate change (King, 1994; Smith et al., 1996, King & Harangozo, 1998; Vaughan et al.,…1 January, 2012 by Andrew Clarke
The mountainous island of South Georgia, situated in the cold but productive waters of the Southern Ocean, is one of the world’s most important seabird islands. It is estimated that…1 January, 2012 by Andrew Clarke, Eugene Murphy, Nadine Johnston
Antarctica offers an unrivalled natural laboratory for fundamental research on the evolutionary processes that shape biological diversity on both local and regional scales. Physiologists and ecologists have long been attracted…Read more on Introduction – Antarctic ecology in a changing world
1 January, 2012 by Mark Clilverd
On 5 April 2010 a series of energetic electron injections, acceleration, and loss events appeared to induce an operational anomaly in the Galaxy 15 geosynchronous communications satellite. We describe the…1 January, 2012 by Claire Allen, Dominic Hodgson
Establishing accurate chronologies for Late Quaternary Antarctic marine sediments is often a challenge due to variable radiocarbon reservoir effects, the presence of coarse-grained glacial material and a lack of carbonate…1 January, 2012 by Claire Allen, Dominic Hodgson
Recent modeling suggests that changes in Southern Ocean sea-ice extent potentially regulated the exchange of CO2 release between the ocean and atmosphere during glacials. Unfortunately, a lack of high-resolution sea-ice…1 January, 2012 by Gabriele Stowasser, Hugh Venables, Martin Collins, Peter Enderlein, Sophie Fielding
Mesopelagic fish are a key component of the pelagic ecosystem throughout the world’s oceans. Opening and closing nets were used to investigate patterns in the distribution and abundance of mesopelagic…1 January, 2012 by Jennifer Jackson
Estimating the abundance of long-lived, migratory animals is challenging but essential for managing populations. We provide the first abundance estimates of endangered humpback whales Megaptera novaeangliae from their breeding grounds…1 January, 2012 by Peter Convey
Some of the most rapidly changing ecosystems on our planet are located in the polar regions (IPCC 2007; Turner et al. 2009; SWIPA 2011). In some areas of the Arctic…Read more on The impacts of climate change on circumpolar biodiversity
1 January, 2012 by Andrew Clarke, David Barnes, Eugene Murphy, Huw Griffiths, Katrin Linse, Nadine Johnston, Peter Convey, Susie Grant
In this chapter we refer to the ‘Antarctic’ in its widest sense. On land, we include the Antarctic continent and Peninsula, the various archipelagos of the Scotia arc, and the…Read more on Biogeography and Regional Classifications of Antarctica
1 January, 2012 by Kevin Hughes, Peter Convey
Antarctic terrestrial biodiversity is challenged by rapid climatic changes and expansion of the human footprint. As well as the potential for environmental damage at the local level, these challenges are…1 January, 2012 by Howard Roscoe
Amounts of source gases with stratospheric sinks (CFCs, N2O, CH4) are affected by changes in BrewerDobson circulation. Source gases and their degradation products are important for atmospheric chemistry and climate.…1 January, 2012
Previous work has demonstrated that exposure to an hour of bright light in the morning and the evening during the Polar winter has beneficial effects on circadian phase. This study…1 January, 2012 by John King
This paper details the event, recording instrumentation, and verification of a new world extreme three-second average wind gust record of 113.3 m s–1, measured on Barrow Island, Australia, during the…1 January, 2012 by Philip Trathan, Richard Phillips, Stacey Adlard
In avian species that have evolved life-history strategies wherein molt and breeding overlap, there are potential conflicts between the regulatory roles of baseline prolactin and corticosterone in parental care (positive)…1 January, 2012 by Derren Fox, Philip Trathan, Richard Phillips
Physiological mechanisms mediating carryover effects, wherein events or activities occurring in one season, habitat, or life-history stage affect important processes in subsequent life-history stages, are largely unknown. The mechanism most…1 January, 2012 by Philip Trathan
It has long been held that Eudyptes penguins will only ever develop a maximum of two mature yolky follicles to match their invariant two-egg clutch, an idea inferred largely from…1 January, 2012 by Chester Sands, Sandra McInnes, Sandra McInnes
Recent studies have suggested that some resident Antarctic biota are of ancient origin and may have been isolated for millions of years. The phylum Tardigrada, which is part of the…1 January, 2012 by Eric Wolff
Based on the fundamental and distinctive physical properties of polycrystalline ice lh, the chemical and temperature profiles within the polar ice sheets, and the observed selective partitioning of bacteria into…1 January, 2012
Migratory divides are contact zones between breeding populations that use divergent migratory routes and have been described in a variety of species. These divides are of major importance to evolution,…1 January, 2012 by Mark Clilverd
On 4 August 2010 a moderate geomagnetic storm occurred with minimum Dst of −65 nT and maximum Kp of 7−. Shortly after the onset of this storm, VLF chorus was…Read more on Simultaneous observation of chorus and hiss near the plasmapause
1 January, 2012 by Kevin Newsham
We investigated the relationships between fungal community composition, latitude and a range of physicochemical parameters in 58 soils sampled from a 2370 km latitudinal gradient between South Georgia (54°S, 38°W)…1 January, 2012 by Peter Convey
global changes are prompting scientists and governments to consider the risk of extinction of species inhabiting environments influenced by ice. Concerted, multidisciplinary, international programmes aimed at understanding life processes, evolution…1 January, 2012 by Gareth Marshall
A 200-year proxy for northerly air mass incursions (NAMI) into central and western West Antarctica is developed from the examination of 19 shallow (21–150 m deep) Antarctic ice-core non-sea-salt (nss)…Read more on An ice-core proxy for northerly air mass incursions into West Antarctica
1 January, 2012 by Huw Griffiths, Katrin Linse
Sponges play a key role in Antarctic marine benthic community structure and dynamics and are often a dominant component of many Southern Ocean benthic communities. Understanding the drivers of sponge…Read more on Diversity and distribution patterns in high southern latitude sponges
1 January, 2012
The roots of a British Antarctic policy can be traced, paradoxically, back to the establishment of a meteorological station by the Scottish Antarctic Expedition in the South Orkneys, in 1903,…Read more on From Scotia to ‘Operation Tabarin’: developing British policy for Antarctica
1 January, 2012
For over 50 years the Antarctic has been governed through the Antarctic Treaty, an international agreement now between 49 nations of whom 28 Consultative Parties (CPs) undertake the management role.…Read more on Leadership in politics and science within the Antarctic Treaty
1 January, 2012 by Mervyn Freeman
Background: Ecologists are collecting extensive data concerning movements of animals in marine ecosystems. Such data need to be analysed with valid statistical methods to yield meaningful conclusions. Principal Findings: We…1 January, 2012 by William Block
Juvenile instars of four species of the oribatid mite family Ameronothridae— Alaskozetes antarcticus intermedius, Ameronothrus lineatus, Halozetes crozetensis and Pseudantarcticola georgiae—are described and illustrated in detail. Known juvenile instars of…Read more on Morphology of juvenile instars of Ameronothridae (Acari: Oribatida)
1 January, 2012 by Roger Worland, Peter Convey
During the 1960s, the midge, Eretmoptera murphyi, was transferred from sub-Antarctic South Georgia (55oS 37oW) where it is endemic to a single location on maritime Antarctic Signy Island (60oS 45oW).…1 January, 2012 by Roger Worland, Peter Convey
A directional primary succession with moderate species replacement was quantitatively characterized on Signy Island in zones of a glacial valley corresponding to their age since deglaciation. A continuous increase in…1 January, 2012 by Hugh Venables, Jonathan Watkins, Martin Collins, Peter Enderlein, Sophie Fielding
Multifrequency acoustic backscatter data were examined from transects at eight stations across the Scotia Sea, from the South Orkneys to the north west of South Georgia. These transects were repeated…1 January, 2012 by Victoria Peck
Two major types of glycerol dialkyl glycerol tetraethers (GDGTs) are commonly used in paleoecological and paleoclimatological reconstructions: isoprenoidal and branched GDGTs. In aquatic environments, it was originally assumed that isoprenoidal…1 January, 2012 by Philip Trathan
Several methods, each with specific advantages and disadvantages, are frequently used to obtain diet samples from seabirds. The collection of regurgitates (REG) as well as samples from the stomach water-off-load…1 January, 2012 by Elaine Fitzcharles
Correct identification of species forms the basis of all biological studies from individual genetic variation to population genetics, stock assessments and understanding whole ecosystems. This often relies on skilled taxonomists…1 January, 2012 by Geraint Tarling, Philip Trathan, Sophie Fielding
Antarctic krill Euphausia superba (hereafter ‘krill’) occur in regions undergoing rapid environmental change, particularly loss of winter sea ice. During recent years, harvesting of krill has increased, possibly enhancing stress…1 January, 2012 by Philip Leat, Robert Mulvaney, Teal Riley
New Pb analyses of K feldspars (Kfs) from Archaean–Mesozoic crystalline rocks from across the Weddell Sea region of Antarctica show Pb isotopic compositions that vary geographically. Five distinct basement provinces…1 January, 2012 by Sandra McInnes, Sandra McInnes
The number of described species on the planet is about 1.9 million, with ca. 17,000 new species described annually, mostly from the tropics. However, taxonomy is usually described as a…1 January, 2012 by Jaume Forcada, Philip Trathan
The compound effects of changing habitats, ecosystem interactions, and fishing practices have implications for the management of Antarctic krill and conservation of its predators. For Antarctic pack-ice seals, an important…1 January, 2012 by Richard Phillips
Marine environments are greatly affected by climate change, and understanding how this perturbation affects marine vertebrates is a major issue. In this context, it is essential to identify the environmental…1 January, 2012
This study investigates the statistical significance of the trends of station temperature time series from the European Climate Assessment & Data archive poleward of 60°N. The trends are identified by…1 January, 2012
This study investigates the significance of trends of four temperature time series—Central England Temperature (CET), Stockholm, Faraday-Vernadsky, and Alert. First the robustness and accuracy of various trend detection methods are…1 January, 2012
The objective of this work is to evaluate the potential of reduced order models to reproduce the extreme event and predictability characteristics of higher dimensional dynamical systems. A nonlinear toy…Read more on Predictability of extreme events in a nonlinear stochastic-dynamical model
1 January, 2012 by Richard Phillips
Aim: An understanding of the non-breeding distribution and ecology of migratory species is necessary for successful conservation. Many seabirds spend the non-breeding season far from land, and information on their…1 January, 2012 by Peter Fretwell
Studying emperor penguins used to be a job for heroes. But penguins leave traces; thanks to high-resolution satellites they can waddle but they cannot hide. Peter Fretwell comes in from…1 January, 2012 by Andrew Fleming, Adrian Fox, Norman Ratcliffe, Philip Trathan, Peter Fretwell
Our aim was to estimate the population of emperor penguins (Aptenodytes fosteri) using a single synoptic survey. We examined the whole continental coastline of Antarctica using a combination of medium…1 January, 2012 by Thomas Bracegirdle
An unusually deep (961 hPa) hurricane-like polar low over the Barents Sea during 18–21 December 2002 is studied by a series of fine-mesh (3 km) experiments using the Weather Research…1 January, 2012 by Jennifer Jackson
Sixteen years of fluke photo identifications have been used to create datasets of the New Caledonia humpback whale breeding ground (IWC sub-stock E2). Estimates of abundance have been calculated using…Read more on An anomalous increase in the New Caledonia humpback whales breeding sub-stock E2
1 January, 2012 by Povl Abrahamsen
The fourth workshop of the South Atlantic Meridional Overturning Circulation (SAMOC 4) took place in Simons Town, South Africa, on 27-29 September 2011. The main objectives of the workshop were…Read more on South Atlantic Meridional Overturning Circulation (SAMOC) – Fourth Workshop
1 January, 2012
and sea level for the past 50 Ma have increased. In parallel, efforts to model ice sheet changes during this period have been ongoing. We review published paleodata and modeling…1 January, 2012 by Emily Shuckburgh, Jean-Baptiste Sallee, Michael Meredith
The Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) was designed as a multi-pronged US and UK CLIVAR effort to measure and to better understand diapycnal mixing and…Read more on The Diapycnal and Isopycnal Mixing Experiment: A First Assessment
1 January, 2012 by David Vaughan
Over the last two decades, the Greenland ice sheet (GrIS) has been losing mass at an increasing rate, enhancing its contribution to sea-level rise (SLR). The recent increases in ice…1 January, 2012 by Paul Holland
A numerical model for an interacting ice shelf and ocean is presented in which the iceshelf base exhibits a channelized morphology similar to that observed beneath Petermann Gletscher’s (Greenland) floating…Read more on Ice-shelf basal channels in a coupled ice/ocean model
1 January, 2012 by Hilmar Gudmundsson
Longitudinal surface structures (“flowstripes”) are common on many glaciers but their origin and significance are poorly understood. In this paper we present observations of the development of these longitudinal structures…Read more on Longitudinal surface structures (flowstripes) on Antarctic glaciers
1 January, 2012 by Eugene Murphy, Geraint Tarling, Will Goodall-Copestake
Estimates of genetic diversity represent a valuable resource for biodiversity assessments and are increasingly used to guide conservation and management programs. The most commonly reported estimates of DNA sequence diversity…1 January, 2012 by Emilie Capron
Although the Last Interglacial (LIG) is often considered as a possible analogue for future climate in high latitudes, its precise climate evolution and associated causes remain uncertain. Here we compile…1 January, 2012 by James Smith
The glacial history of the continental shelf northwest of Alexander Island is not well known, due mainly to a lack of targeted marine data on Antarctica's palaeo-ice sheets in their…1 January, 2012 by Peter Convey
Three exotic species of Collembola are here identified in collections made during surveys on subantarctic South Georgia in the summers of 2005/2006 and 2009/2010. Previously, only two exotic species of…Read more on Exotic Collembola on subantarctic islands: pathways, origins and biology
1 January, 2012 by Peter Convey
Three new non-indigenous springtail species are recorded in recent collections made on Deception Island, South Shetland Islands, maritime Antarctic: Deuteraphorura (Deuteraphorura) cebennaria (Gisin) (Collembola: Onychiuridae), Mesaphorura macrochaeta Rusek (Tullbergiidae), and…1 January, 2012 by Thomas Lachlan-Cope
In-situ aircraft observations of ice crystal concentrations in Antarctic clouds are presented for the first time. Orographic, layer and wave clouds around the Antarctic Peninsula and Larsen Ice shelf regions…1 January, 2012 by Hilmar Gudmundsson
The stability of marine ice sheets grounded on beds that slope upwards in the overall direction of flow is investigated numerically in two horizontal dimensions. We give examples of stable…Read more on The stability of grounding lines on retrograde slopes
1 January, 2012 by Roger Worland, Peter Convey
In order to contribute to the reconstruction of the deglaciation history of the Marguerite Bay area (~ 68°S, Maritime Antarctic) and to estimate the rock weathering rate in this Antarctic…1 January, 2012 by Roger Worland
A CALM grid with a data logger system to monitor the active layer thermal regime was established on Signy Island (60°43′S, 45°38′Wat 80 m a.s.l.) in December 2005. The active…1 January, 2012
During the heroic age of Antarctic exploration, a number of the early explorers developed psychiatric illness either in the Antarctic or shortly after leaving it. Most of these were psychotic…Read more on Psychiatric illness and suicide in the heroic age of Antarctic exploration
1 January, 2012
The psychology of Antarctic explorers and groups in Antarctic bases has been much studied in recent years, and current knowledge has been summarized in a review by Palinkas and Suedenfeld…Read more on Psychology during the expeditions of the heroic age of Antarctic exploration
1 January, 2012
Reginald Koettlitz was born in Ostend but moved to England as a child and qualified at Guy's Hospital. He was a general practitioner in County Durham for eight years before…Read more on Dr Reginald Koettlitz (1860-1916): Arctic and Antarctic explorer
1 January, 2012
Frostbite and other cold injuries on the early polar expeditions were common. This paper explains how frostbite was described, prevented, and treated on the Antarctic expeditions of the heroic age,…Read more on Frostbite and other cold injuries in the heroic age of Antarctic exploration
1 January, 2012
During the heroic age of Antarctic exploration, snow blindness was a common problem, but not all the descriptions of it lit the modern view of the disease, and some of…Read more on Snow blindness and other eye problems during the heroic age of Antarctic exploration
1 January, 2012
This paper explores the role of the doctor on the expeditions of the heroic age of Antarctic exploration. The medical role includes medical screening of prospective expedition members, choosing medical…Read more on The role of the expedition doctor: Lessons From 100 years ago
1 January, 2012 by Huw Griffiths, John Turner, Lloyd Peck, Melody Clark, Peter Convey, Thomas Bracegirdle, Zhaomin Wang
Developments of future scenarios of Antarctic ecosystems are still in their infancy, whilst predictions of the physical environment are recognized as being of global relevance and corresponding models are under…1 January, 2012 by Lloyd Peck, Melody Clark, Simon Morley
We document differences in shell damage and shell thickness in a bivalve mollusc (Laternula elliptica) from seven sites around Antarctica with differing exposures to ice movement. These range from 60%…Read more on Iceberg Scour and Shell Damage in the Antarctic Bivalve Laternula elliptica
1 January, 2012 by Ailsa Stroud
The REgents PARk and Tower Environmental Experiment (REPARTEE) comprised two campaigns in London in October 2006 and October/November 2007. The experiment design involved measurements at a heavily trafficked roadside site,…1 January, 2012 by Claus-Dieter Hillenbrand
We analyzed 214 new core-top samples for their CaCO3 content from shelves all around Antarctica in order to understand their distribution and contribution to the marine carbon cycle. The distribution…Read more on Distribution and mineralogy of carbonate sediments on Antarctic shelves
1 January, 2012 by Richard Phillips
The distributions of many marine birds, particularly those that are highly pelagic, remain poorly known outside the breeding period. Here we use geolocator-immersion loggers to study trans-equatorial migration, activity patterns…1 January, 2012 by Michael Meredith
The supply of nutrients to the low-latitude thermocline is largely controlled by intermediate- depth waters formed at the surface in the high southern latitudes. Silicic acid is an essential macronutrient…1 January, 2012 by Andrew Clarke
A high resolution time-series analysis of stable carbon isotopic signatures in particulate organic carbon (delta C-13(POC)) and associated biogeochemical parameters in sea ice and surface waters provides an insight into…1 January, 2012 by Eugene Murphy, Simeon Hill
Foodweb models provide a useful framework for compiling data on biomass, production, consumption and feeding relationships. They are particularly useful for identifying gaps and inconsistencies in the data, and for…Read more on A foodweb model to explore uncertainties in the South Georgia shelf pelagic ecosystem
1 January, 2012 by Guy Hillyard, Melody Clark
Fifteen species of marine invertebrate commonly occurring in the near-shore environment of Rothera base, Antarctica, were used to test tissue sample storage protocols with regard to preservation of RNA integrity.…Read more on RNA preservation of Antarctic marine invertebrates
1 January, 2012 by Richard Hindmarsh, Richard Hindmarsh
An analytical theory is developed for ice flow velocity in a boundary layer couplet at the calving front. The theory has simple quantitative characteristics that relate ice front velocity to…1 January, 2012
The Southern Ocean is largely a High Nutrient Low Chlorophyll (HNLC) region where macronutrient concentrations are high and phytoplankton productivity is low. However, there are productive ‘hot spots’ that sustain…Read more on Responses of microplankton community structure to iron addition in the Scotia Sea
1 January, 2012
The Southern Ocean is an important biogeochemical region on a global scale, in which mineralising phytoplankton play a role in cycling energy, carbon and nutrients. Mineralising phytoplankton with cells 2–20…1 January, 2012 by Andreas Cziferszky, Dominic Hodgson, Peter Convey, Peter Fretwell
We studied the glacial geomorphology and geochronology of two ice-free valleys in the Dufek Massif (Antarctic Specially Protected Area 119) providing new constraints on past ice sheet thickness in the…1 January, 2012 by Lloyd Peck, Melody Clark
Although recent years have witnessed a rapid growth in the number of genetic studies of Antarctic organisms, relatively few studies have so far used nuclear markers, possibly due to the…1 January, 2012 by Jaume Forcada, Melody Clark
Although single nucleotide polymorphisms (SNPs) are increasingly being recognized as powerful molecular markers, their application to non-model organisms can bring significant challenges. Among these are imperfect conversion rates of assays…1 January, 2012 by Andrew Clarke, Lloyd Peck, Melody Clark, Peter Fretwell
Several recent empirical studies have challenged the prevailing dogma that broadcast-spawning species exhibit little or no population genetic structure by documenting genetic discontinuities associated with large-scale oceanographic features. However, relatively…1 January, 2012 by Jaume Forcada
Natal philopatry is an important component of mammalian behaviour but is difficult to study in natural vertebrate populations due to the requirement for long-term individual-based spatial observations. Consequently, we quantified…Read more on Extreme natal philopatry in female Antarctic fur seals (Arctocephalus gazella)
1 January, 2012 by Paul Holland
The sea-ice cover around Antarctica has experienced a slight expansion in area over the past decades1, 2. This small overall increase is the sum of much larger opposing trends in…