Showing 11929 items
1 January, 1987
The Dimitobelidae is a Cretaceous belemnite family that was restricted to within the 30° S. palaeolatitude for its Aptian-Maastrichtian range. The family is described in detail from the Antarctic Peninsula…Read more on The Cretaceous Dimitobelidae (Belemnitida) of the Antarctic Peninsula region
1 January, 1987
The deep minimum in total ozone, the ‘ozone hole’, which is now observed each year in early spring in Antarctica, appears to be confined to the cold core of the…Read more on Recent measurements of total ozone at British Antarctic Survey stations
1 January, 1987
Linear belts 50–100 km in width of long-wavelength positive magnetic anomalies exceeding 500 nT are observed on continental blocks of the Scotia arc. The most developed is the West Coast…Read more on Continental magnetic anomalies and the evolution of the Scotia arc
1 January, 1987
Aspects of the breeding biology of the whitc‐chinned petrel Procellaria aequinoctialis were studied at South Georgia. Laying, hatching and fledging dates, together with egg and adult measurements, rate of weight…1 January, 1987
Antarctic fish of the family Channichthyidae (Icefishes) lack the respiratory pigments haemoglobin and myoglobin. The morphometrics and ultrastructure of the ventricular myocardium of a benthic icefish,Chaenocephalus aceratus has been compared…Read more on Morphometrics and ultrastructure of myocardial tissue in Notothenioid fishes
1 January, 1987 by William Block
Soil biological processes which have been studied in the north are extended and compared with those of the south polar region. Much can be learned from exploiting the biological similarities…Read more on Soil biological processes in the North – and South
1 January, 1987
1. Oxygen consumption, mitochondrial content and enzyme activities were determined in identified muscle fibre types of the ‘haemoglobin-less’ icefish Chaenocephalus aceratus Lonnberg. 2. Small bundles (2–12) of fast and slow…1 January, 1987
Second only to auroral kilometric radiation as the Earth's most prominent radio emission, magnetospheric nonthermal continuum radiation has been the subject of numerous observational and theoretical investigations. It has been…Read more on The magnetopause as a source of nonthermal continuum radiation
1 January, 1987
57 morphological characters were scored on a sample of 46 male and 55 characters on a sample of 40 female Gamasellus racovitzai, which had been collected from 10 localities in…1 January, 1987
(1) The sub-Antarctic island of South Georgia has a species-poor vascular flora that is not adapted to grazing by vertebrates. Consequently, reindeer (Rangifer tarandus L.) introduced to different areas of…1 January, 1987 by William Block
Polyacrylamide gel electrophoresis and subsequent esterase staining provide an alternative to immunological methods for investigating the diet of microarthropods which cannot be observed directly. Attack rates in field populations of…1 January, 1987 by Andrew Clarke, Lloyd Peck
The living terebratulid articulate brachiopod Liothyrella uva (Jackson 1912) was sampled from a shallow water population at Signy Island, South Orkney Islands, Antarctica. Neither shell height nor shell breadth were…1 January, 1987
A synthetic aperture radar (SAR) technique has been used to image part of the grounding-line region of Bach Ice Shelf in the Antarctic Peninsula. The radar was sledge-mounted and operated…Read more on Imaging subglacial topography by a synthetic aperture radar technique
1 January, 1987 by Keith Nicholls
A model pulsed wavefield is presented that enables the behaviour of the associated wave dislocations to be computed exactly. It consists of three intersecting beams of plane-wave pulses. Because the…Read more on Three-beam model for studying dislocations in wave pulses
1 January, 1987
We report a distribution—free approach to the detection of density—dependence in the variation of population abundance, measured by a series of annual censuses. The method uses the correlation coefficient between…Read more on The detection of density-dependence from a series of annual censuses
1 January, 1987
This paper discusses the present understanding of ionospheric storms, in particular storm effects in the F-layer and their relationship to changes of thermospheric composition. After summarizing the main effects of…1 January, 1987
Over the past 50 years, ideas relating to the physical features and dynamics of ice sheets have evolved materially, primarily due to modern technological advances in the acquisition of basic…Read more on Fifty years of progress in understanding ice sheets
1 January, 1987
Average north polar currents for the winter season have been derived from geomagnetic hourly means at six levels of geomagnetic activity. The twin-vortex pattern, normally associated with more disturbed conditions,…Read more on The effect of geomagnetic activity on north polar currents in winter
1 January, 1987
The poleward edge of the main ionospheric trough can often be regarded as the ionospheric signature of the equatorward boundary of the plasma sheet. We use Advanced Ionospheric Sounder observations…Read more on Is the poleward edge of the trough a sensitive indicator of geospace interactions?
1 January, 1987 by Paul Rodhouse
Cephalopod beaks from the stomach contents of “wandering albatross” (Diomedea exulans L.) chicks from Bird Island, South Georgia, were sampled between May and September in 1983 and 1984. Lower beaks…Read more on Cephalopod prey of the wandering albatross Diomedea exulans
1 January, 1987
Optical methods of studying the atmosphere are one valuable means of investigating atmospheric behaviour at heights ranging from less than 1 km to several hundred km. Some examples are given…Read more on Antarctica — A unique laboratory for atmospheric studies by optical methods
1 January, 1987
Declination, or the difference between true and magnetic north, is one of the earliest parameters to have been measured systematically over the earth's surface. Values are available for South Georgia…Read more on Measurement of declination at South Georgia 1700–1984
1 January, 1987
A model has been constructed which grafts IRI topside profiles to field-aligned diffusive equilibrium profiles at a “reference level” near 650 km altitude. For different values of geographic latitude, longitude,…Read more on A suggested model for the IRI plasmapheric distribution
1 January, 1987
The impacts of pollution resulting from large explosive volcanic eruptions on the atmospheric heat budget and planetary albedo are not in doubt1,2. However, the effects of volcanic aerosols on the…Read more on Global surface-temperature responses to major volcanic eruptions
1 January, 1987
The plasmapause and the mid-latitude ionospheric trough have been observed simultaneously from two Antarctic stations, Halley and Faraday, during five winter nights covering a range of geomagnetic disturbance conditions. The…1 January, 1987
The soluble carbohydrate and polyhydric alcohol (polyol) content of fruticose lichens, cushion mosses and early vegetative colonizers of maritime Antarctic fellfield soils were examined by gas-liquid chromatography during 18 months.…1 January, 1987
Gas liquid chromatography and a commercially available strip of 20 conventional biochemical tests were used for the rapid sorting of strains of environmental bacterial isolates into similar ecophysiological groups. This…1 January, 1987 by Peter Ward
The reproductive biology of the predatory calanoid copepod Euchaeta antarctica Giesbrecht was investigated in two interconnected fjord systems at South Georgia. Counts of the number of spermatophores attached to adult…1 January, 1987
New analysis procedures are used to show that the main phase mid-latitude storm effects conform to consistent patterns in local time when suitable selection rules are applied, with averaging over…15 November, 1986
A year‐long tidal record has been obtained from beneath the George VI Ice Shelf, Antarctica. An unusual feature of the record is a significant response in tidal species 3 to…Read more on The tidal spectrum underneath Antarctic ice shelves
1 November, 1986
We have examined the variations of electron precipitation at L ≈ 4 as inferred from riometer measurements of cosmic radio noise absorption made during 1975 at Siple Station and Halley…1 September, 1986
Nonthermal continuum is observed at 1.2 kHz on Voyagers 1 and 2 within the Jovian magnetosphere. It is seen in the magnetospheric cavity on both the dayside and nightside, being…1 July, 1986
A series of 50 male and 42 female mites of the prostigmatid family Tydeidae from the maritime Antarctic were each scored for 67 morphological characters. Ordination of each data set…1 June, 1986
Blood samples were collected from free-living incubating Diomedea albatross during single incubation shifts, both daily (wandering albatross D. exulans and every 2 days (grey-headed albatross D. chrysostoma and black-browed albatross…Read more on Corticosterone secretion through long incubation shifts in Diomedea albatrosses
1 June, 1986 by Alistair Crame
As a result of recent field work, a new lithostratigraphic group is defined on the west coast of James Ross Island, Antarctica. Characterised by comparatively coarse-grained sediments, the Gustav Group…Read more on Lithostratigraphy of the Cretaceous strata of west James Ross Island, Antarctica
1 February, 1986
Gonadal size and the circulating concentrations of two pituitary hormones (luteinizing hormone and prolactin) and three gonadal steroids (testosterone, progesterone and oestradiol‐17β) were measured in two closely related Diomedea albatrosses…1 February, 1986
(1) A sampling programme has been designed to detect whether multiple scales of pattern (or aggregation) occur in arthropod distributions. A secondary aim was to relate arthropod pattern with environmental…1 January, 1986
Se describen areniscas del Cretacico Superior, expuestas en las cercanias de Punta Arenas, sur de Chile, las que exhiben laminacion convoluta y estratificacion cruzada, tipo "hummocky". Estas capas se formaron…1 January, 1986
1. Single fast and small bundles of slow fibres were isolated from the muscles of an elasmobranch (dogfish, Scyliorhinus canicula) and an Antarctic teleost (Notothenia neglecta). A third fibre type…1 January, 1986
1. Force and ATPase activity were measured in skinned, fast muscle fibres isolated from the myotomes of Antarctic, temperate and tropical fish. 2. Maximum isometric tension was inversely related to…1 January, 1986
Samples of adult Alaskozetes antarcticus, an Antarctic cryptostigmatid mite, were collected in winter and summer. In 4 separate experiments, mites were maintained under relative humidities in the range: 0, 26,…Read more on Effects of contrasting relative humidities on the cold tolerance of an Antarctic mite
1 January, 1986
Samples of a cryptostigmatid mite, Alaskozetes antarcticus, were collected during summer and winter on Signy Island, South Orkney Islands, in the maritime Antarctic. In four experiments, adult mites were maintained…Read more on Effects of ingestion of liquids on the cold tolerance of an Antarctic mite
1 January, 1986
On occasion the third hop of an echoing magnetospheric whistler exceeds the first hop in intensity over some low range of frequencies. Case studies show that this anomalous behavior can…Read more on The third hop whistler anomaly: possible evidence of df/dt-dependent wave amplification