Showing 11205 items
1 January, 1991
Energy expenditure of fasting territorial male Antarctic fur seals at South Georgia was measured by mass loss and analysis of carcass composition using tritium dilution in 1987 and 1988. Mean…1 January, 1991
A histochemical and electron microscopy study was carried out on muscle growth in demersal stages of the Antarctic teleost Notothenia neglecta Nybelin. The total number of myotomal muscle fibres was…Read more on Muscle growth in the Antarctic teleost, Notothenia neglecta (Nybelin)
1 January, 1991
The intense magnetic storm of December 19, 1980 occurred during a major rocket and balloon geophysical research campaign at Siple Station, Antarctica. A balloon flight measuring the electric field and…Read more on The intense magnetic storm of December 19, 1980: Observations atL= 4
1 January, 1991
Analyses of a core from the deepest known moss peat bank in Antarctica, on Elephant Island, South Shetlands, show that this Chorisodontium aciphyllum-dominated bank began to grow ca. 5500 14C…1 January, 1991 by John Turner
Analysis of AVHRR data collected during the summer and winter over the Ross Ice Shelf reveals complex patterns of curvilinear stripes. In particular, a large, looping pattern of stripes is…1 January, 1991 by Andrew Clarke
The deep-water prawn Pandalus borealis Kroyer, 1838 was sampled at six locations from Krossfjord, Spitsbergen (79⚬N, close to the known northerly limit of distribution) to Kosterfjord, Sweden (58⚬N, close to…Read more on Egg Size and Reproductive Output in the Deep-Water Prawn Pandalus borealis Kroyer, 1838
1 January, 1991 by Andrew Clarke, Lloyd Peck
The polar marine environment is characterised by low stable temperatures with seasonal variations ranging from ±3°C at lower latitudes to only ±0.2°C at high latitudes. The Arctic basin is dominated…1 January, 1991 by Mark Clilverd
Whistler mode group delays from the VLF Doppler experiment at Faraday, Antarctica (65°S, 64°W) show an annual variation that has a maximum in December and a minimum in June/July. Assuming…1 January, 1991
The pattern and characteristics of diving of two male blue‐eyed shags Phalacrocorax atriceps were studied, using continuous‐recording time‐depth recorders, for a total of 15 consecutive days during which the depth,…Read more on Diving patterns and performance in the Antarctic blue-eyed shag Phalacrocorax atriceps
1 January, 1991
The attachment to artificial substrata (carborundum paper) of cyanobacteria and algae isolated from Antarctic fellfield soils was investigated using a simulated flow apparatus. Generally, the rugosity of the substratum was…1 January, 1991
The survival and growth of four genera of cyanobacteria and microalgae isolated from Antarctic fellfield soils were investigated. Survival of freezing and desiccation were studied by vital staining, and the…Read more on Effects of physical factors on the survival and growth of antarctic terrestrial algae
1 January, 1991
Investigation of the seasonal changes in composition of an immature Antarctic fellfield cyanobacterial/microalgal community has demonstrated a repeated periodicity. The community consisted of only 14 species. Early spring growth of…Read more on The seasonal periodicity of algae on Antarctic fellfield soils
1 January, 1991 by John Turner
Seasat's contributions to ice sheet glaciology are explored with emphasis on the experience gained from this mission and on how this has assisted in defining future satellite missions. The sensors…Read more on The contribution of Seasat to ice sheet glaciology
1 January, 1991
1. Plasma metabolites and nutrients of macaroni penguins (Eudyptes chrysolophus) arriving on land in good condition, following intense feeding, for breeding and moulting were investigated. 2. The pre-breeding female birds…1 January, 1991 by Adrian Jenkins
Detailed glaciological studies have been completed at 28 sites lying on an approximate flow line, extending 760 km across Ronne Ice Shelf. Parameters measured at each location include ice velocity,…Read more on Ice-ocean interaction on Ronne Ice Shelf, Antarctica
1 January, 1991 by William Block
Live and dead specimens of the Antarctic collembolan Cryptopygus antarcticus (Willem) dry, under constant external conditions of temperature (25 or 35°C) and r.h. (0%), like most hygric soil arthropods. The…Read more on Drying processes in the Antarctic collembolan Cryptopygus antarcticus (Willem)
1 January, 1991
Samples of Loligo gahi (D'Orbigny) were collected from commercial fishing vessels in the Falkland Islands Interim Conservation and Management Zone (FICZ) between March and October 1987, and from the R/V…Read more on Post-recruit growth of the Patagonian squid Loligo gahi (d’Orbigny)
1 January, 1991
Sundström (1986) erected the genus Proboscia for solenoid diatoms whose valves tapered to a proboscis, but only assigned one species to it, the boreal Rhizosolenia alata Brightwell. We have found…1 January, 1991
Five fossil species of Rhizosolenia are known only from the distal parts of the valve. The resemblance of these tubular structures to the proboscis of the modern genus Proboscia Sundström,…1 January, 1991
During winter 1989 at South Georgia, gentoo penguins showed a very rapid change in diet over a 10-day period. On 11-12 July, food samples were of low masses (150g) and…1 January, 1991 by John King
1 January, 1991
THE tectonic fabric of the sea floor created at spreading ridges generally curves in the direction of ridge offset near transform faults, owing to the influence of shearing stress on…Read more on Unusual sea-floor fabric near the Bullard fracture zone imaged by GLORIA sidescan sonar
1 January, 1991
Different environmental conditions, particularly daylength and intensity of natural light, may influence the ability of shiftworkers to adapt to the abrupt phase-shifts of 24 h time cues imposed by the…1 January, 1991
Halozetes belgicae is distributed widely in the Subantarctic and maritime Antarctic, with subspecies described from Macquarie Island and the South Sandwich Islands. A morphometrical study, based largely on the development…Read more on The cryptostigmatid mite Halozetes belgicae (Michael) in the maritime Antarctic
1 January, 1991
The dielectric profiling (DEP) technique is described and some of the differences between it and standard electrical tools used in ice core analysis are discussed. The results of DEP analysis…Read more on Application of the dielectric profiling technique to ice core studies
1 January, 1991
Early diagenetic (precompactional) concretions are abundant throughout the Cretaceous-Tertiary Marambio Group Larsen Basin, Antarctica. Four distinct concretion types are recognised: (1) spherical-subspherical concretions: (2) sheet concretions; (3) fossil-nucleated concretions; and…1 January, 1991
The polar regions are unique laboratories for carrying out research on both the atmosphere and the near-Earth space environment. The relatively undisturbed conditions help us explore phenomena like the greenhouse…Read more on Atmospheric and space research from polar regions
1 January, 1991
Whistler activity at L ≃ 4 is known to be a function of longitude, peaking in the Weddell Sea sector of Antarctica; a combination of source and propagation factors, the…1 January, 1991
Eight isolates of bacteria from the soils of maritime Antarctica and Antarctic peninsula have been identified as members of the genus Janthinobacterium. Based on their morphology, physiological characteristics, biochemical characteristics…1 January, 1991 by Andy Smith
New tiltmeter data are presented from Doake Ice Rumples on Ronne Ice Shelf, Antarctica. Five sites which showed a tidal ice-shelf flexure have been analysed using an elastic beam model…Read more on The use of tiltmeters to study the dynamics of Antarctic ice-shelf grounding lines
1 January, 1991
Six species of Stereocaulon and one unnamed taxon (close to S. glabrum) are reported from South Georgia, the maritime Antarctic islands and Antarctic Peninsula. S. caespitosum is new to the…Read more on The lichen genus Stereocaulon in Antarctica and South Georgia
1 January, 1991
The Advanced Ionospheric Sounder at Halley (75° 31′S, 26° 59′W) in Antarctica has been used to observe the F-region disturbance caused by an atmospheric gravity wave. Observations at 4.5 MHz…Read more on Compression and rarefaction of F-region plasma caused by an atmospheric gravity wave
1 January, 1991
The world's largest colony of the black-browed albatross Diomedea melanophrys on Steeple Jason Island, Falkland Islands was systematically censused for the first time in December 1987. Colony area was estimated…1 January, 1991
Results from a detailed profile in a 5.54 m multi-year sea-ice core from the rift area in the southern part of George VI Ice Shelf are presented. Stratigraphy, stable isotopes…1 January, 1991
A precise Rb‐Sr isochron age of 97.0 ± 0.5 Ma is presented for whole‐rock and mineral samples from the Mandamus Igneous Complex, North Canterbury. A low 87Sr/ 86Sr initial ratio…1 January, 1991
The reliability of various criteria (throat feather length and the characteristics of rectrices and upper tail‐coverts) previously suggested for ageing Starlings was assessed using a sample of known‐aged birds. Total…Read more on Ageing criteria in the Starling Sturnus vulgaris
1 December, 1990 by Andrew Clarke
Several recent studies have shown the potential value of chloroform-soluble fluorescent age pigments (FAPs) in determining the age of marine invertebrates with no permanent hard parts. The primary assumption in…Read more on The accumulation of fluorescent age pigments in the trochid gastropod Monodonta lineata
1 December, 1990 by Alistair Crame, John Turner
The International Conference on the Role of the Polar Regions in Global Change was hosted by the Geophysical Institute and Center for Global Change and Arctic System Research of the…Read more on Role of the polar regions in global change. Fairbanks, Alaska, 11–15 June 1990
1 December, 1990
The structural relationship between West Antarctic crustal blocks has remained uncertain due to a lack of information concerning sub‐ice crustal structure. A regional aeromagnetic reconnaissance of Ellsworth Land between 72…1 December, 1990 by Richard Horne
The range of applicability of an improved quasilongitudinal approximation for whistler-mode waves in the equatorial magnetosphere (4 ≲ L ≲ 6.6) is specified based on the direct comparison between numerical…Read more on Quasilongitudinal approximation for whistler-mode waves in the magnetospheric plasma
1 December, 1990
Marie Byrd Land is amongst the most inaccessible and least visited regions of Antarctica. It contains a large alkaline volcanic province, with 18 large central volcanoes and numerous small satellitic…1 December, 1990
Population growth rates of Antarctic and temperate isolates of the microflagellate Heteromita globosa Stein and of the ciliate Colpoda cucullus Müller were determined during incubation both under constant 3.5° and…1 December, 1990
The diversity of bacterial communities isolated from Antarctic lake sediment in chemostats under constant low temperature (8°C) or diurnally fluctuating temperature (1°C to 16°C) was examined. The median optimum temperature…Read more on The selection of microbial communities by constant or fluctuating temperatures
1 December, 1990
(1) Radio-telemetry was used to study the activity patterns of gentoo penguins, Pygoscelis papua, at Bird Island, South Georgia, throughout the breeding season, to assess variation in foraging effort (foraging…1 December, 1990
In crested penguins, Eudyptes spp., the first-laid (A) egg is smaller than the second-laid (B) egg and although viable rarely survives to hatching. I studied survival and growth to fledging…1 November, 1990 by Richard Horne
The ray paths of unstable electromagnetic waves generated inside the plasmapause during magnetic storm conditions are followed using the HOTRAY code. Unducted waves which are preferentially generated in the field…Read more on Ion cyclotron absorption at the second harmonic of the oxygen gyrofrequency
1 November, 1990
Digital ionosondes such as the Dynasonde disclose that the ionosphere is seldom horizontal even when it is plane stratified to a good approximation. The local magnetic dip does not then…1 October, 1990 by Michael Pinnock
The Geospace Environment Modeling (GEM) Program is directed toward modeling the coupled solar wind/magnetosphere/ionosphere system. The inter‐calibration of ground‐based observations of the ionosphere and satellite observations has been identified as…Read more on Simultaneous HF-radar and DMSP observations of the cusp
1 October, 1990 by Paul Rodhouse
Cephalopod remains were collected, at regular intervals throughout the fledging period, from the stomach contents of chicks of the grey-headed albatrossDiomedea chrysostoma at Bird Island, South Georgia, in 1984 and…Read more on Cephalopod prey of the grey-headed albatross Diomedea chrysostoma
1 October, 1990
Earlier views regarding the relative insignificance of Antarctic science have been rudely shattered by recent developments. The International Geophysical Year (IGY) of 1957–1958 represented a major turning point for research…Read more on Science, environment and resources in Antarctica
1 October, 1990 by Jonathan Watkins
An effect of the very patchy distribution of Antarctic krill (Euphausia superba Dana) in various forms of aggregation is that a single swarm may not provide an unbiased estimate of…Read more on Sampling biological characteristics of krill: Effect of heterogeneous nature of swarms
1 October, 1990
The breeding biology of the gentoo penguin, Pygoscelis papua, was studied over a three‐year period (1986–1988) at Bird Island, South Georgia, with particular reference to birds of known age or…1 September, 1990
The arrival of Antarctic fur seals at a breeding beach on Bird Island, South Georgia, was studied over five consecutive breeding seasons, 1983 to 1987. Experienced bulls arrived first and…1 September, 1990 by William Block
Nematodes of the families Heterorhabditidae and Steinernematidae are obligate parasites of a wide range of insects (Poinar 1979). The third stage juvenile of these nematodes is a non-feeding infective form…Read more on Tests of Antarctic soils for insect parasitic nematodes
1 September, 1990 by Paul Rodhouse
Post-recruit Illex argentinus were collected from the fishery on the Patagonian Shelf between 1986 and 1988. Age was determined by analysis of daily growth increments in ground sections of the…1 September, 1990
Our understanding of polar vegetation and climate through time has expanded enormously in the past five years as a consequence of improved logistics, detailed studies of plant fossils in their…Read more on Climate change and the evolution of high-latitude terrestrial vegetation and floras
1 September, 1990
The Shackleton Range occupies a key geological position in Antarctica (Fig. 1). Its location, at the edge of the continental craton between the mobile belts of the Transantarctic Mountains (TAM)…Read more on European geological initiative for the Shackleton Range
1 September, 1990 by Eric Wolff
In their upper layers, the polar ice sheets contain a detailed record of changes in the atmosphere over the industrial period. Measurements from air bubbles in ice have shown that…Read more on Signals of atmospheric pollution in polar snow and ice
1 August, 1990 by Peter Ward
A net sampling survey was conducted around the island of South Georgia in the austral summer 1981/1982 and again in winter 1983. This paper uses Principal Components Analysis to elucidate…Read more on Mesoscale distribution of zooplankton around South Georgia
1 August, 1990 by Lloyd Peck
Modified micro-Winkler and couloximetric methods are described for the measurement of oxygen in small volumes of water. The former uses a sample size of 1 cm3, while the latter is…Read more on Two methods for the assessment of the oxygen content of small volumes of seawater
1 July, 1990
Subduction of young, hot oceanic lithosphere and a major episode of lithospheric extension have been considered as key tectonomagmatic factors in the genesis of ‘Setouchi-type’ continental magnesian andesites. We present…1 July, 1990
A model has been set up to investigate the wet and dry aerosol removal processes which occur in clean air over the Antarctic Peninsula. Input for the model was obtained…1 June, 1990 by Michael Pinnock
Two conjugate HF radars are currently operating at Goose Bay, Labrador, and Halley Station, Antarctica, and are providing continuous, high temporal resolution measurements of plasma convection over large areas of…1 June, 1990
Three species of free-living Antarctic fellfield nematodes, Eudorylaimus coniceps, E. spaulli and E. pseudocarteri exhibited differing degrees of both strategies of cold-hardiness; freeze-tolerance and freeze-avoidance. Bimodal distributions of supercooling points…Read more on Strategies of cold-hardiness in three species of Antarctic dorylaimid nematodes
1 May, 1990
The relationship between quasi-periodic VLF emissions and micropulsations is briefly reviewed, and then discussed with reference to an event recorded at Halley, Antarctica, on day 257 in 1986. VLF emissions…Read more on Quasi-periodic particle precipitation and Trimpi activity at Halley, Antarctica
1 May, 1990
Two‐dimensional models are presented for the crustal structure of the Antarctic Peninsula, a Mesozoic‐Cenozoic magmatic arc on the southeast Pacific margin. The models are constrained by measured rock properties. The…1 May, 1990 by Paul Rodhouse
Growth increments have been reported to occur in the squid beak, radula, gladius and statolith. Of these, the statolith, which is part of the organ responsible for detection of linear…Read more on Age determination in squid using statolith growth increments
1 May, 1990
LEP (lightning electron precipitation) bursts can be detected on the ground because they cause transient perturbations (known as ‘Trimpi events’) in the received amplitude and phase of subionospherically propagating radio…Read more on The trimpi effect in antarctica: observations and models
1 April, 1990 by Richard Horne
The narrow-band structure of terrestrial myriametric radiation (TMR) is investigated by ray tracing electrostatic waves in a hot plasma which contains a loss cone distribution. Path-integrated growth of electrostatic waves…Read more on Narrow-band structure and amplitude of terrestrial myriametric radiation
1 April, 1990
Distribution, size composition and behaviour of Euphausia superba were investigated in the northwestern Weddell Sea (59–63°S, 45–52°W) in October-November 1988 using RMT trawling, SCUBA diving and visual examination of the…1 April, 1990 by Roger Worland, William Block
1. Freezing was lethal in the eggs, larvae, pupae and adults of the blowflies Calliphora vicina R‐D. and Calliphora vomitoria (L.), but varying degrees of supercooling were found. 2. Cold…Read more on Cold resistance in all life stages of two blowfly species (Diptera, Calliphoridae)
1 April, 1990
Adult Antarctic fur seals (Arctocephalus gazella) were immobilized with Zoletil® (n= 172), ketamine (n= 30), ketamine mixed with diazepam (n= 23) and with ketamine mixed with xylazine (n= 45). Response…1 April, 1990
Cortaderia pilosa is the dominant pasture species in the Falkland Islands. Extensive sheep ranching for wool production is the primary land use, but present range management grossly under-utilizes the annual…1 April, 1990
Under conditions of moderately-energetic particle precipitation typical of the equatorward side of the auroral oval, plasma densities obtained from routine analysis of EISCAT Common Program data are often a factor…1 March, 1990
We studied the distribution and abundance of marine birds in Bransfield Strait and southern Drake Passage during January and February 1985. We identified clusters of bird species, “communities” with similar…1 March, 1990
The regional geology and lithostratigraphy of the Late Cretaceous strata of north-east James Ross Island have been described by a number of authors (e.g. Olivero et al. 1986, Pirrie 1989).…1 March, 1990
In recent years, Man has become increasingly aware of the damage that he is doing to the Earth's atmospheric environment. There are two separate-but interrelated-effects, namely the greenhouse effect due…Read more on The Antarctic atmosphere: A hot topic in a cold cauldron
1 March, 1990
Antarctic cryptogamic communities are often remarkable for their uniformity in vegetation structure and floristic composition. Many typically exist as closely related units of vegetation in a continuum of variation which…Read more on Plant community dynamics in Wilkes Land, Antarctica