Showing 11923 items
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…1 January, 2000 by Jonathan Watkins
Much of the distribution range of Antarctic krill, Euphausia superba, is covered by permanent or seasonal sea ice. Sea ice extent has been implicated as a major factor affecting reproductive…Read more on Effects of sea ice cover on the swarming behaviour of Antarctic krill,Euphausia superba
1 January, 2000
On Bird Island, South Georgia, albatrosses (n = 140), penguins (n = 100), and fur seals (n = 206) were sampled for Campylobacter jejuni. C. jejuni subsp. jejuni was recovered…1 January, 2000
1 The population density, diversity and productivity of the microbial plankton in an oligotrophic maritime Antarctic lake were studied for a 15-month period between December 1994 and February 1996. 2…Read more on Temporal plankton dynamics in an oligotrophic maritime Antarctic lake
1 January, 2000
Cetricycas antarcticus gen. et sp. nov. occurs in the Late Coniacian to Campanian Lachman Crags Member of the Santa Marta Formation, Marambio Group, James Ross Island, Antarctica. The petrified trunk…Read more on A petrified cycad trunk from the Late Cretaceous of the Larsen Basin, Antarctica
1 January, 2000
A macroflora from John Peaks, Powell Island, contains Sagenopteris nilssoniana, Cladophlebis oblonga, Brachyphyllum sp., Elatocladus confertus, and Sphenopteris sp. The macroflora is best correlated with the Botany Bay Group flora,…1 January, 2000
Publication of the Composite gazetteer of Antarctica by the SCAR Working Group on Geodesy and Geographic Information is a major milestone in the evolution of Antarctic toponymy. It has taken…1 January, 2000 by Gareth Chisham, Michael Pinnock
Poleward‐moving line‐of‐sight velocity “flow bursts” have been observed in the cusp by two southern hemisphere SuperDARN HF radars with overlapping fields‐of‐view. This has allowed the estimation of unambiguous two‐dimensional velocity…1 January, 2000 by Gareth Chisham, Michael Pinnock
We present data from conjugate SuperDARN radars describing the high-latitude ionosphere's response to changes in the direction of IMF By during a period of steady IMF Bz southward and Bx…1 January, 2000 by Andrew Clarke
1. We have examined large-scale geographical patterns in species richness for continental shelf bryozoan assemblages in the North Atlantic. Bryozoans are common and often abundant benthic organisms, but they have…1 January, 2000
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ∼106 km2 and total as much as…Read more on The state and future of Mars polar science and exploration
1 January, 2000 by Mark Clilverd
Unusually low whistler mode group delay times are observed by VLF Doppler receivers at both Faraday, Antarctica, and Dunedin, New Zealand, following magnetic storms. These are typically caused by plasmaspheric…1 January, 2000 by Michael Pinnock
The antiparallel merging hypothesis states that reconnection takes place on the dayside magnetopause where the solar and geomagnetic fields are oppositely directed. With this criterion, we have mapped the predicted…Read more on The ionospheric footprint of antiparallel merging regions on the dayside magnetopause
1 January, 2000
We aim to identify the important steps in the evolution of the ecosystem approach to management under the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR). The first…1 January, 2000 by Peter Convey
The South Sandwich Islands are an isolated maritime Antarctic volcanic island arc 550-600km south-east of South Georgia. The terrestrial biology of the islands, with emphasis on the unique habitats associated…Read more on The terrestrial micro-arthropod fauna of the South Sandwich Islands
1 January, 2000 by Dominic Hodgson, Helen Peat, Peter Convey
Aim To carry out as comprehensive a survey as practicable of the flora (higher plants, mosses, liverworts, lichens, basidiomycete fungi and diatoms) of the isolated, volcanically active, South Sandwich Islands…1 January, 2000 by Helen Peat, Peter Convey
This paper documents the previously undescribed terrestrial fauna (mites, nematodes, tardigrades) and flora (liverworts, mosses and lichens) of Marion Nunataks, Charcot Island (69°45'S 075°15'W). Species diversity in all groups is…1 January, 2000 by Roger Worland, Peter Convey
In studies of three common, freezing susceptible, Antarctic microarthropods, the springtail Cryptopygus antarcticus and the mites Alaskozetes antarcticus and Halozetes belgicae, we report (i) the consequences on cold tolerance of…Read more on Refining the risk of freezing mortality for Antarctic terrestrial microarthropods
1 January, 2000 by Roger Worland, Peter Convey
Free-living microbivorous nematodes become numerically dominant in Antarctic terrestrial faunas as environmental conditions become more severe, while also reaching very high levels of abundance in moist, vegetated habitats. Nematodes have…Read more on Survival of freezing by free-living Antarctic soil nematodes
1 January, 2000 by Alistair Crame
A major new inventory of living marine Bivalvia (Mollusca) is based on 29 regional faunas. These again pick out strong latitudinal and longitudinal gradients in taxonomic diversity, but there are…1 January, 2000
In a previous study at South Georgia, carnivory was invoked as a cause of high polyunsaturated fatty acid (PUFA) content of Antarctic krill, Euphausia superba. To examine this, krill were…1 January, 2000 by Lloyd Peck
A complete energy balance equation is calculated for the Antarctic octopus Pareledone charcoti at 0°C. Energy used in respiration, growth, and excretion of nitrogenous and faecal waste, was recorded along…Read more on Energy balance and cold adaptation in the octopus Pareledone charcoti
1 January, 2000 by Paul Rodhouse
In the summer of 1995/96, 25 southern elephant seals, Mirounga leonina, were stomach lavaged at Stranger Point, King George Island, South Shetland Islands. Cephalopod remains were present in 72% of…1 January, 2000
Bipolarity, the presence of a species in the high latitudes separated by a gap in distribution across the tropics, is a well-known pattern of global species distribution. But the question…1 January, 2000
Biomolecules, such as the productive and protective pigments of photosynthetic organisms, are good biomarkers in extreme Antarctic deserts as analogues of early Mars. Laser Raman technology at long wavelengths which…1 January, 2000
A review is made of stratigraphical, geochemical and palaeogeographical data from the northern Antarctic Peninsula and the Southern Ocean for Late Mesozoic-Early Cenozoic times. Clay mineral and S/total organic C…1 January, 2000 by Peter Convey, Sandra McInnes, Sandra McInnes
A small collection of samples from terrestrial and fresh-water habitats on Deception Island in the Maritime Antarctic South Shetland archipelago yielded 14 invertebrate taxa, including four species, which are new…1 January, 2000 by Roger Worland, William Block
DSC analysis was performed at three points in the cryopreservation process on encapsulated-dehydrated meristems of Ribes ciliatum. Meristems were excised from shoots pre-treated with either sucrose or glucose, encapsulated in…1 January, 2000
The Raman spectrum of the photoprotective pigmentscytonemin found in cyanobacterial sheaths has been obtained for the first time. Its skeletal structure is extensively conjugated and unique in nature. Detailed molecular…1 January, 2000
Spawning by Antarctic fish is generally considered to be seasonal and restricted to a brief period during the autumn and winter. Arising from this it has been assumed that the…Read more on Inter-annual variation in the gonad cycle of the mackerel icefish