Showing 11862 items
1 January, 2001
The proportion of Patagonian toothfish Dissostichus eleginoides, caught around South Georgia in the south-west Atlantic, with empty stomachs was much lower in fish caught in pots compared to longlines (28…Read more on The stomach contents of Patagonian toothfish around South Georgia (South Atlantic)
1 January, 2001 by Michael Pinnock
Previous work has shown that ionospheric HF radar backscatter in the noon sector can be used to locate the footprint of the magnetospheric cusp particle precipitation. This has enabled the…1 January, 2001 by Eric Wolff
Assessing changes in heavymetals concentrations in Antarcticsnow dated from the last century is of high interest to determine to which extent the most remote regions of our planet are contaminated…1 January, 2001
The wood flora from Williams Point, Livingston Island, contains 12 wood types of gymnosperm and angiosperm origin. Recent collections of material have increased the biodiversity of a postulated species-rich vegetation.…1 January, 2001
Early Tertiary sediments of the Antarctic Peninsula region continue to yield a rich assemblage of well-preserved fossil dicotyledonous angiosperm wood. The wood flora under consideration is from the Collins Glacier…1 January, 2001 by Lloyd Peck
Sperm concentration and sperm ageing effects on fertilisation success were evaluated in the laboratory in the free-spawning Antarctic soft-shelled clam Laternula elliptica and Antarctic limpet Nacella concinna. Fertilisation success was…1 January, 2001
The retreat of five small Antarctic Peninsula ice shelves in the late 20th century has been related to regional (possibly anthropogenic) climate warming. We use the record of ice- rafted…1 January, 2001
We present preliminary results of the first detailed surveys of the former Larsen-A Ice Shelf, Larsen Inlet aiid southern Prince Gustav Channel. where disintegration of small ice shelvcs in the…1 January, 2001
Fourteen species of littoral Acari (Arachnida) were collected from the shores of sub-Antarctic Marion Island, of which Parasitiphis brunneus (Kramer) (Ologamasidae), Rhombognathus apsteini Lohmann and R. gressitti Newell (Halacaridae) are…Read more on Littoral Acari of Marion Island: ecology and extreme wave action
1 January, 2001
Data on population size, breeding success and diet composition of gentoo (Pygoscelis papua), magellanic (Spheniscus magellanicus) and rockhopper (Eudyptes chrysocome) penguins, collected as part of the Falkland Island Seabird Monitoring…1 January, 2001
El margen proto-andino de Gondwana ha sido el escenario de al menos dos orogénesis desde el desmembramiento del supercontinente Rodinia al final del Neoprotrozoico, hasta el reagrupamiento de las masas…1 January, 2001
During oceanographic cruises in 1996 and 1998, phytoplankton from 15 stations in the southwest Atlantic sector of the Southern Ocean were incubated at ambient temperature and 2 elevated temperatures (ambient…1 January, 2001
Antarctic krill Euphausia superba has a central role in the ecosystem of the Southern Ocean and knowledge of its growth rate is central to determining the factors influencing population dynamics.…Read more on Growth of Antarctic krill Euphausia superba at South Georgia
1 January, 2001
The relationship between krill abundance and predator performance is fundamental to an ecosystem-based approach to resource management. We propose a method using krill sampled from the diet of predators to…1 January, 2001
Long-term changes in the physical environment in the Antarctic Peninsula region have significant potential for affecting populations of Antarctic krill (Euphausia superba), a keystone food web species. In order to…1 January, 2001 by Teal Riley
Extensive outpourings of basalt, and to a lesser extent rhyolite, are closely associated with continental break-up and plume-lithosphere interactions. The Gondwana supercontinent began to fiagment during Early-Middle Jurassic times and…1 January, 2001 by Philip Leat, Teal Riley
Voluminous rhyolitic volcanism along the palaeo-Pacific margin of Gondwana was marked by three principal episodes of magmatism. The first of these ( V1) is essentially coincident with the main episode of…1 January, 2001 by Andrew Clarke, Lloyd Peck
Seawater temperatures in Antarctica are low, and typically rather stable seasonally. Associated with this, many marine invertebrates have low resting metabolic rates with a limited aerobic scope, and are often…1 January, 2001 by Andrew Clarke
The mean rate of oxygen consumption in fasted Saduriaentomon increased between 4°C and 13°C with a Q10 of 2.33. After feeding, rates of oxygen uptake increased significantly by two- to…1 January, 2001 by Mark Clilverd
It has recently been suggested that successive intense lightning‐electromagnetic pulse (EMP) events could cause significant large‐scale changes to the properties of the nighttime lower ionosphere. In order to examine this…1 January, 2001 by Paul Rodhouse
Squid are short-lived ecological opportunists which generally have a lifespan of about 1 year. Their populations are labile and recruitment variability is driven, to a greater or lesser extent, by…Read more on Managing and forecasting squid fisheries in variable environments
1 January, 2001 by Howard Roscoe
Using a flexible chemical box model with full heterogeneous chemistry, intercepts of chemically modified Langley plots have been computed for the 5 years of zenith-sky NO2 data from Faraday in…1 January, 2001 by Anna Jones, Howard Roscoe
Ozone at Faraday in Antarctica is measured by a ground-based visible spectrometer. Total ozone is deduced from the slant column measurements by means of calculated air-mass factors (AMFs), which have…1 January, 2001 by Howard Roscoe
Sudden loss of tropospheric ozone well above the boundary layer was observed on three occasions at two coastal sites in Antarctica in spring 1995. Back trajectories show that the air…1 January, 2001 by Howard Roscoe
Stratospheric H2O is increasing, and may be responsible for a large part of the observed cooling of the lower stratosphere. Further cooling will lead to more PSCs in the edge…1 January, 2001 by Howard Roscoe
Ozone depletion at mid-latitudes is caused by reactivehalogens from man-made halocarbons. The stratosphericsulphate aerosol which follows large volcaniceruptions enhances (multiplies) this ozone depletion(it has no effect on ozone without halocarbons).…1 January, 2001
New isotopic ages and a fresh understanding of stratigraphic relations among siliciclastic strata in the Pensacola Mountains along the northern margin of the East Antarctic craton result in removal of…1 January, 2001 by Helen Peat, Peter Convey
The morphology, size and characteristics of the pollen of the plant species Antarctic hairgrass (Deschampsia antarctica, Poaceae) and Antarctic pearlwort (Colobanthus quitensis, Caryophyllaceae) are described by scanning electron microscopy and…1 January, 2001
A geomorphological sketch map of the Fossil Bluff area, showing the main morphological characteristics was prepared from aerial photographs taken by the British Antarctic Survey in 1995. Landforms and deposits…1 January, 2001 by Eric Wolff
A tentative age scale (EDC1) for the last 45 kyr is established for the new 788‐m EPICA Dome C ice core using a simple ice flow model. The age of…Read more on A tentative chronology for the EPICA Dome Concordia Ice Core
1 January, 2001 by Hugh Corr
The Pine Island Glacier (PIG) transports 69 cubic kilometers of ice each year from ∼10% of the West Antarctic Ice Sheet (WAIS). It is possible that a retreat of the…Read more on Inland Thinning of Pine Island Glacier, West Antarctica
1 January, 2001
Over 70 lakes have now been identi®ed beneath the Antarctic ice sheet. Although water from none of the lakes has been sampled directly, analysis of lake ice frozen (accreted) to…1 January, 2001
Detrital modes determined on 68 sandstone samples from CRP-3 drillcore indicate a continuation of the dynamic history of uplift-related erosion and unroofing previously documented in CRP-1 and CRP-2/2A. The source…1 January, 2001
Deception Island is the most active volcano in the Antarctic Peninsula region. It is a large basalt–andesite shield volcano with a 10 km-wide restless caldera (Port Foster) and a complicated…Read more on Lithostratigraphy and volcanic evolution of Deception Island, South Shetland Islands
1 January, 2001
The consensus of several geochemical studies is a polygenetic origin for the basic volcanic sequence within the Ballantrae Complex ophiolite. This overall agreement masks differences of opinion regarding local geochemical…1 January, 2001 by Mark Clilverd
From a statistical study of ductedwhistlers observed at Halley, Antarctica, in 1996, which had propagated on paths in the range L=2.5–4.5, we report mean occurrence rates, numbers of components per…Read more on A quantitative estimate of the ducted whistler power within the outer plasmasphere
1 January, 2001
VLF whistler observations from Eights Station, Antarctica were crucial to the discovery and exploration of the plasmapause (''Carpenter's knee'') by Don Carpenter in the mid-1960s. The Weddell Sea sector of…1 January, 2001
Observations on the abundance of medusae at the surface were conducted in the northern Benguela ecosystem, over the period August 1997–June 1998. The results suggest that Chrysaora hysoscella is found…1 January, 2001 by Iain Staniland
The rate of regurgitation of food from the stomachs of trawl caught whiting Merlangius merlangus was negatively correlated with fish size. Increased musculature of the oesophageal sphincter in larger fish…1 January, 2001 by Robert Mulvaney
We report measurements of brominated, bromochlorinated, and iodinated methanes in air extracted from deep firn at three polar locations (two Antarctic and one Arctic). Using a firn diffusion model, we…Read more on Methyl bromide, other brominated methanes, and methyl iodide in polar firn air
1 January, 2001
The drillhole at CRP-3 was the deepest of the project and offered early hopes of retrieving a long plalaeontological record. However, the reality was that the fossil content dropped off…Read more on Palaeontological studies for CRP-3: introduction
1 January, 2001 by Mark Clilverd
Enhancements of D-region electron densities caused by solar flares are determined from observations of VLF subionospheric amplitude changes and these enhancements are then related to the magnitudes of the X-ray…Read more on Solar flare induced ionospheric D-region enhancements from VLF amplitude observations
1 January, 2001 by Michael Pinnock
Super Dual Auroral Radar Network (SuperDARN) HF radar, magnetometer, and satellite data are used to study ionospheric convection flow bursts in the sunward return flow in the 1200–1500 MLT auroral…Read more on Flow transients in the postnoon ionosphere: The role of solar wind dynamic pressure
1 January, 2001
Summary 1 Several albatross species, including the wandering albatross Diomedea exulans, have shown marked declines in abundance throughout their range. These seabirds are frequently taken as by-catch in longline fisheries…Read more on Modelling the impact of fishery by-catches on albatross populations
1 January, 2001 by Gareth Marshall, John Turner
A description is given of an automatic cloud detection scheme that has been developed for year-round, routine use on full (1.1 km) horizontal-resolution, five-channel Advanced Very High Resolution Radiometer (AVHRR)…1 January, 2001 by John Turner
An assessment is presented of the extent and variability of Antarctic sea ice in the non-flux-corrected version of the Hadley Centre's coupled atmosphere-ocean general circulation model (HadCM3). The results are…Read more on The simulation of Antarctic sea ice in the Hadley Centre Climate Model (HadCM3)
1 January, 2001 by Gareth Marshall, John Turner, Thomas Lachlan-Cope
Model output, satellite data, and in situ observations are used to investigate the conditions that gave rise to an extreme wind event at the Australian Casey Station (66.27°S, 110.53°E) on…Read more on An extreme wind event at Casey Station, Antarctica
1 January, 2001 by David Vaughan, Gareth Marshall, John King, Robert Mulvaney
Global surface temperatures have increased by 0.6 � 0.2°C in the last century, but this warming has not been evenly distributed across the globe. Some regions, such as the Antarctic…1 January, 2001 by Vsevolod Afanasyev
We apply the theory of random walks to quantitatively describe the general problem of how to search efficiently for randomly located objects that can only be detected in the limited…1 January, 2001 by Vsevolod Afanasyev
We discuss recent findings suggesting that an inverse square probability density distribution P(ℓ)∼ℓ−2 of step lengths ℓ leads to an optimal random search strategy for organisms that can search efficiently…Read more on Lévy flights search patterns of biological organisms
1 January, 2001 by Claire Waluda, Paul Rodhouse, Philip Trathan
In this study, we consider the influence of mesoscale oceanographic processes around the Falkland Islands (Islas Malvinas) in the South-west Atlantic, during the period in which the commercial squid fishery…1 January, 2001 by Claire Waluda, Paul Rodhouse, Philip Trathan
In this study, we consider the influence of mesoscale oceanographic processes around the Falkland Islands (Islas Malvinas) in the South-west Atlantic, during the period in which the commercial squid fishery…1 January, 2001 by Peter Ward
In recent years, much attention has been paid to the Antarctic epipelagic fauna, as a result of the desire to increase our knowledge of ecosystem function and resource management. Unfortunately,…Read more on The deep-sea copepod fauna of the Southern Ocean: patterns and processes
1 January, 2001 by Teal Riley
Cambrian volcanic rocks of the Liv Group, defined here as including the Wyatt, Ackerman, Taylor, Fairweather, and Leverett Formations, occur along the paleo-Pacific margin of Gondwana, in the Queen Maud…1 January, 2001 by Mark Clilverd
We compare measurements for 1998 of VLF sferics-generated noise power at Halley, Antarctica, with the predictions of the long wave noise prediction (LNP) noise model. We compare the highest-ranked predicted…1 January, 2001 by Mark Clilverd
Lightning is considered to be a sensitive indicator of global change in the troposphere. In this paper we report the first results from the lightningatmospherics (sferics) counter deployed as part…Read more on Lightning atmospherics count rates observed at Halley, Antarctica
1 January, 2001 by Mervyn Freeman
As noted by Chang, the hypothesis of self-organised criticality provides a theoretical framework in which the low dimensionality seen in magnetospheric indices can be combined with the scaling seen in…Read more on Testing the SOC hypothesis for the magnetosphere
1 January, 2001 by Mervyn Freeman
The interaction between the Earth's magnetic field and the solar wind plasma results in a natural plasma confinement system which stores energy. Dissipation of this energy through Joule heating in…Read more on Ambiguities in determination of self-affinity in the AE-index time series
1 January, 2001 by Mervyn Freeman
We determine that the sizes of bursts in mean-square current density in a reduced magnetohydrodynamic (RMHD) simulation follow a power-law probability density function (PDF). The PDFs for burst durations and…1 January, 2001
The provisioning parameters, breeding success, adult mass, and survival of yellow-nosed albatrosses were studied over 7 successive years at Amsterdam Island, southern Indian Ocean. We examined the ability of this…1 January, 2001 by Roger Worland
The loss during desiccation of osmotically active water (OAW), which freezes during cooling to -45 °C, and osmotically inactive water (OIW), which remains unfrozen, from the cysts of the potato…1 January, 2001
The presence of authigenic smectite in the lower Oligocene sandstones of the Cape Roberts Project core CRP-3 from the Victoria Land Basin of Antarctica is confirmed by scanning electron, scanning-transmission…1 January, 2001 by Roger Worland, Peter Convey
1 Rapid cold hardening was examined in three common Antarctic microarthropods using differential scanning calorimetry over timescales between 3 and 30 h, under field and controlled laboratory conditions. 2 In…Read more on Rapid cold hardening in Antarctic microarthropods
1 January, 2001
Antarctic astrobiological research has benefited from the affiliation of the UK Astrobiology Forum (UKAF) to the NASA Astrobiology Institute (NAI). NAI funding of a miniature Raman spectrometer for the characterization…1 January, 2001
Water, vital for life, not only maintains the integrity of structural and metabolic biomolecules, it also transports them in solution or colloidal suspension. Any flow of water through a dormant…Read more on Brines in seepage channels as eluants for subsurface relict biomolecules on Mars?
1 January, 2001 by Martin Collins
The Patagonian toothfish Dissostichus eleginoides has been the object of a rapidly expanding longline fishery in the Southern Ocean. Little is known about the biology of D. eleginoides and traditional…1 January, 2001
SHRIMP analyses of detrital zircon cores from high-grade metasediments from the Mid-German Crystalline Rise, which is situated between Eastern Avalonia in the NW and Saxo-Thuringia in the SE, yield mostly…1 January, 2001
Metapelitic gneisses from the Glenfinnan Group of the Moine Supergroup, Scotland, contain sparse large and numerous small garnets, associated with complex zoned epidote and plagioclase in a biotite matrix. The…1 January, 2001
Sediment cores from the continentalrise west of the AntarcticPeninsula and the northern Weddell and ScotiaSeas were investigated for their ice-rafted debris (IRD) content by lithofacies logging and counting of particles…30 December, 2000
We have identified first evidence for the presence of submarine hydrothermal activity along the East Scotia Ridge an isolated back-arc spreading centre located at 55–60°S in the Atlantic sector of…1 June, 2000 by Nigel Meredith, Richard Horne
The temporal evolution of electron distributions and associated wave activity following substorm injections in the inner magnetosphere are investigated using data from the CRRES satellite. Equatorial electron distributions and concomitant…1 January, 2000
A series of experiments was carried out in February 1999 at South Georgia (Subarea 48.3) to examine the effects of different weighting regimes on the incidental mortality of birds caught…1 January, 2000 by Michael Pinnock
The Super Dual Auroral Radar Network (SuperDARN) radars are proving to be a very powerful experimental tool for exploring solar wind-magnetosphere-ionosphere interactions. They measure the autocorrelation function (ACF) of the…1 January, 2000 by Lloyd Peck
Antarctic anemones of the genus Halcampoides inhabit low intertidal and shallow subtidal zones. They readily burrow into soft sediments following disturbance. The process of re-burying was recorded using time-lapse video…Read more on Burrowing in the Antarctic anemone, Halcampoides sp., from Signy Island, Antarctica
1 January, 2000
Large, biomass-dominant Southern Ocean copepod species have been much studied, but small and mesopelagic species also play major rôles in these ecosystems. However, little is known of some basic aspects…1 January, 2000
Excretion by Antarctic krill Euphausia superba (hereafter ‘‘krill’’) is measured typically in small containers of filtered seawater for 12–24 h, which may cause a reduction of swimming, feeding, and metabolism.…Read more on Ammonium excretion by Antarctic krill Euphausia superba at South Georgia
1 January, 2000
The Mana Pools sedimentary basin lies within the Zambezi mobile belt in northern Zimbabwe. New and preexisting magnetotelluric data and the available seismic reflection data are used to constrain the…Read more on A magnetotelluric model of the Mana Pools basin, northern Zimbabwe
1 January, 2000 by Roger Worland, William Block
Hydromedion sparsutum is a locally abundant herbivorous beetle on the sub-Antarctic island of South Georgia, often living in close association with the tussock grass Parodiochloa flabellata. Over a 4-day period…1 January, 2000 by David Vaughan
It has been suggested that as much as 90% of the discharge from the Antarctic Ice Sheet is drained through a small number of fast-moving ice streams and outlet glaciers…Read more on Widespread complex flow in the interior of the Antarctic Ice Sheet
1 January, 2000
Phosphorus is scarce in Beacon Sandstone of the McMurdo Dry Valleys, Antarctica, and any input from precipitation is minimal. In endolithic microbial communities recycling of P by the action of…Read more on Phosphatase activities of endolithic communities in rocks of the Antarctic Dry Valleys
1 January, 2000
The phosphomonoesterase activity of a microbialcommunity dominated by Chroococcidiopsis in arock sample from the Antarctic dry desert was comparedwith that of a non-axenic culture of thecyanobacterium isolated from the same…1 January, 2000
We report low temperature gradients (from 60% to 12% of geothermal), and extrapolated temperatures offset from modern bottom water temperatures, in sediments from the central Scotia Sea. We examine possible…1 January, 2000
Tape recordings of two types of vocalisations were used to assess burrow occupancy by white-chinned petrels (Procellaria aequinoctialis) at South Georgia. Birds responded to the rattle call on 74% of…1 January, 2000
The white-chinned petrel (Procellaria aequinoctialis) is an abundant, widespread petrel breeding in tussock grassland at sub-Antarctic islands. Over the last decade it has been killed in large numbers in temperate…1 January, 2000
The foraging range and principal feeding areas of White-chinned Petrels breeding at South Georgia were determined using satellite telemetry. Foraging trips during incubation lasted 12–15 days and covered 3000–8000 km…1 January, 2000 by William Block
Specimens of six enchytraeid species from a wide range of terrestrial habitats were cooled to –25oC and rewarmed at 1oC min-1 and their cryobiological features measured by DSC. All were…Read more on DSC studies of freezing in terrestrial enchytraeids (Annelida: Oligochaeta)
1 January, 2000
The absolute gut evacuation rate (GER) (g day−1) of Harpagifer antarcticus increased with increasing ration mass, fish mass only influenced the absolute GER at a daily ration level of 0·3%…1 January, 2000
This study tests the hypothesis that an endothermic homeotherm should minimise heat flux in cold polar waters by minimising skin temperature. Temperature variability was measured at the surface of the…Read more on Skin temperatures during free-ranging swimming and diving in Antarctic fur seals
1 January, 2000
1. The study tested the hypothesis that the occurrence of pregnancy in mammals that are capital breeders will be most closely related to state variables that are indices of food…Read more on State-dependent fertility in pinnipeds: contrasting capital and income breeders
1 January, 2000 by Eugene Murphy, Philip Trathan
Ocean physics is a key aspect of the operation of island ecosystems, yet the hydrodynamics is sometimes poorly understood. A high-resolution oceanographic survey to the north of South Georgia identified…