Found 14046 items
1 January, 1988
New field and laboratory studies result in a redefinition of the three main lithostratigraphic units of the Thiel Mountains. These are (1) the Thiel Mountains porphyry, a massive hypersthene-bearing monzonite,…1 January, 1988
Mesozoic and Cenozoic granitoids of this segment of the Andes occur in three N/S-trending belts: western (WB), central (CB), and eastern (EB). The WB is formed by the Mincha and…1 January, 1988
Hobbs Pool is an area of thin ice shelf situated within George VI Ice Shelf, Antarctica. Thicker ice shelf surrounding Hobbs Pool isolates the upper 155 m of the water…Read more on Localized basal freezing within George VI Ice Shelf, Antarctica
1 January, 1988 by Robert Mulvaney
Whilst stable-isotope analysis of ice cores yields the best quantitative evidence for past climate, there remains considerable uncertainty about the detailed relationship between the isotopic composition and air temperature. Analysis…1 January, 1988
Tide gauge and atmospheric sea level pressure measurements from each side of Drake Passage are compared with multiyear time series of bottom pressure at 500 m depth. Synthetic subsurface pressure…Read more on Comparisons of sea level and bottom pressure measurements at Drake Passage
1 January, 1988
Scintillation data from near Boston, U.S.A., and spread-F data from Argentine Islands, Antarctica are used to investigate the diurnal and seasonal variations of the simultaneous occurrence of medium-scale (~ 1–10…1 January, 1988
When data are transformed for statistical analysis bias occurs when backtransforming means to the untransformed scale. The bias can produce grossly misleading conclusions. Anomalous results of two different analyses are…Read more on A cautionary note on data transformation: bias in back-transformed means
1 January, 1988
(1) This analysis of monitoring data is based on twenty-seven British and Irish colonies where individual guillemots (Uria aalge) were counted repeatedly in clearly defined areas of cliff (plots) 1975-82.…Read more on Analysis of counts from monitoring guillemots in Britain and Ireland
1 January, 1988
The dynamics, radiation, and chemistry of the atmosphere are outlined in an attempt to explain the processes behind springtime Antarctic ozone depletion. Recent observations made by Gardiner and Shanklin (1986)…1 January, 1988
The dynamics of the upper thermosphere in the southern polar cap, auroral, and mid‐latitude zones is reviewed. Information has been drawn from published measurements from the DE 2 and AE‐C…Read more on Southern hemisphere thermospheric dynamics: A review
1 January, 1988
The terrestrial environment of Signy Island, South Orkney Islands, maritime Antarctic, is undergoing rapid and possibly irreversible change caused by a natural biological agent. During the past decade there has…1 January, 1988
Fabry-Perot interferometer Doppler measurements of the 6300 Å oxygen emission line have been used to determine the neutral thermospheric wind over Halley, Antarctica. Simultaneous measurements of the local magnetic field…1 January, 1988
Five post-tectonic granitic plutons isolated within the central Ellsworth-Whitmore mountains crustal block in West Antarctica form a distinctive geochemical suite. All have some characteristics of S-type granites and are atypical…1 January, 1988
The Antarctic Peninsula Mesozoic magmatic arc has had a long history of dextral, strike-slip deformation. The deformation was initially associated with the development of a wide accretionary complex, by the…Read more on Role of strike-slip faulting in the tectonic evolution of the Antarctic Peninsula
1 January, 1988
Of all the world?s continents Antarctica is the coldest, the highest, and the least known. It is one and a half times the size of the United States, and on…Read more on Satellite image atlas of glaciers of of the world – Antarctica
1 January, 1988
A collation of available data shows that sea-water with a temperature 3°C above the in-situ freezing point lies beneath George VI Ice Shelf in the Antarctic Peninsula, and is widespread…Read more on Oceanic environment of George VI Ice Shelf, Antarctic Peninsula
1 January, 1988 by Eric Wolff, Robert Mulvaney
Analysis of an ice sample with an estimated age of 125 years, from the Antarctic Peninsula, using a scanning electron microscope with a cold stage and an X-ray micro-analysis facility,…1 January, 1988 by Eric Wolff
Clean sampling and analysis procedures have been used to measure the concentrations of Al and four heavy metals in snow representing one year’s accumulation (1983-84) near Dye 3 in Greenland.…1 January, 1988
A large (100 km N/S), stable, smoothly‐structured and significant depletion (15% in number density) of the daytime Tromsø F‐region was produced inadvertently during a Heater polarisation and beam‐forming procedure. We…Read more on A large-scale ionospheric depletion by intense radio wave heating
1 December, 1987 by Andrew Clarke, Lloyd Peck
Oxygen consumption and ammonia excretion were measured in Liothyrella uva (Broderip, 1833) held in the laboratory under simulated summer conditions. The mean oxygen consumption of a 50 mg AFDW brachiopod…1 December, 1987
We explore the conditions for resonance between cometary pick-up ions and parallel propagating electromagnetic waves. A model ring—beam distribution for the pick-up H2O+ ions is adopted which allows a direct…Read more on Resonant interactions between cometary ions and low frequency electromagnetic waves
1 October, 1987
Diurnal variations in the vertical distribution and swarming behaviour of Euphausia crystallorophias at Deception Island (61 degrees South, 66 degrees West) are described. Swarms were present at all times of…Read more on Some aspects of the small scale distribution of Euphausia crystallorophias
1 August, 1987
In most species daily and seasonal changes in the light-dark cycle are the most important synchronisers (zeitgebers) of daily and seasonal rhythms. In humans only bright light (2500 lux) appears…Read more on Bright light phase shifts the human melatonin rhythm during the Antarctic winter
1 August, 1987
A patch of high phytoplankton biomass, approximately 109 m2 in area, remained apparently stationary off King George Island, South Shetland Islands, over a period of at least 11 days. The…1 August, 1987
The two sibling species of giant petrels Macronectes halli and M. giganteus are the dominant avian scavengers in the Southern Ocean ecosystem. They breed sympatrically at a number of sub-Antarctic…Read more on Species and sexual isolating mechanisms in sibling species of giant petrels Macronectes
1 July, 1987
Observations by the Dynamics Explorer 1 satellite provide validation of the theory that terrestrial myriametric radiation is produced by the linear conversion of electrostatic upper hybrid waves to electromagnetic radiation…Read more on Observed beaming of terrestrial myriametric radiation
1 June, 1987
Narrow-band jovian kilometric radiation (nKOM) is distinguishable from broad-band jovian kilometric radiation (bKOM), both discovered by the Voyager spacecraft1–3, by its generally lower intensity, its more restricted range of centre…Read more on Io plasma torus and the source of jovian narrow-band kilometric radiation
1 June, 1987
The numerous Miocene-Recent alkaline volcanic outcrops in the Antarctic Peninsula form a substantial volcanic province, the least well-known part of a major belt of alkaline volcanism that extends between South…1 April, 1987
The global solar radiation received at the earth's surface in the presence of cloud depends not only on the optical depth of the cloud and its other physical properties, but…Read more on Solar radiation transmitted to the ground through cloud in relation to surface albedo
1 April, 1987 by Richard Horne
Two types of generating mechanisms have been proposed to explain the observations of weak electrostatic waves near the local upper hybrid frequency fuh. In this paper data from the wave…1 April, 1987 by John King
Observations of internal gravity waves in the stably-stratified atmospheric boundary layer at Halley, Antarctica are presented. These were made on 1 February, 1986 and take the form of temperature measurements…Read more on Observations of an internal gravity wave in the lower troposphere at Halley, Antarctica
1 March, 1987
A magnetospheric substorm that occurred at Sanae, Antarctica, on July 27, 1979, was observed by a variety of techniques. A synthesis of the observations is presented, and an attempt made…Read more on A magnetospheric substorm observed at Sanae, Antarctica
1 March, 1987
As part of a study on freeze‐thaw weathering in the maritime Antarctic an investigation was made of the physical properties of the local rock. Tests were made of point‐load compressive…1 March, 1987
The distribution and fine structure of muscle-fibre types has been determined for the pelagic fingerling and demersal adult stages of the antarctic teleost Notothenia neglecta Nybelin, collected from Signy Island,…1 February, 1987
This study follows the psychological profile of a group of Antarctic explorers on a remote base in British Antarctica. Each month for 1 year the 60-item General Health Questionnaire (GHQ)…1 February, 1987 by William Block
Overwintering Delia radicum (L.) in a field of swedes (Brassica napus L.) near Ascot, Berks., England, were exposed to soil temperatures below 10°C on 176 days from 21 October 1983…1 February, 1987 by Richard Horne
Recent observations from the EISCAT incoherent scatter radar have revealed bursts of poleward ion flow in the dayside auroral ionosphere which are consistent with the ionospheric signature of flux transfer…Read more on Non-Maxwellian ion velocity distributions observed using EISCAT
1 January, 1987
This report is based on a PhD thesis by B.F. Mair submitted to the University of Aberdeen in August 1979, and entitled 'The geology of the area between Drygalski Fjord…Read more on The geology of South Georgia: VI. Larsen Harbour formation
1 January, 1987
This report is based on a PhD thesis by C.G. Smith submitted in 1977.Read more on The geology of parts of the west coast of Palmer Land
1 January, 1987
Six working groups were set up at the joint IUCN/SCAR Symposium on the scientific requirements for Antarctic conservation. These were charged with (i) identifying gaps in the scientific understanding of…1 January, 1987
James Cook in his voyage of 1774–1775 is generally credited with the discovery of the Antarctic. He was soon followed by fur sealers who by the end of the first…Read more on Antarctic science and conservation — The historical background
1 January, 1987
When interpreting observations of radio waves of low frequency in magnetospheric cavities, it is often assumed that the electron concentration is small enough for the ray paths to be treated…Read more on Theory of wave polarization of radio waves in magnetospheric cavities
1 January, 1987
The theory of radio windows given in two previous papers for a stratified cold plasma is extended to apply in a warm plasma. It is used to investigate one suggested…Read more on The theory of radio windows in planetary magnetospheres