Showing 11332 items
1 January, 1992
Trilobites devonicos de Buill, Chile (42°S). Se describe un trilobites calmoniido (Calmoniidae gen. nov. aff. Bainella Rennie, 1930) un trilobites lacopoide indeterminado y un coral zafrentido, recolectados en rodados de…1 January, 1992
In the late 1970s, many people still thought that a cooling trend in the Northern Hemisphere heralded the next ice age. But some were already claiming that rising atmospheric CO2…1 January, 1992
1.1. Dynamics of plasma nutrients and metabolites in moulting macaroni (Eudyptes chrysolophus) and gentoo (Pygoscelis papua) penguins were studied.2.2. The late moult macaroni and gentoo penguins had significantly elevated levels…1 January, 1992
Snow Petrels (Pagodroma nivea) breed circurnpolarly in Antarctica. Watson et al. (1971), Harper et al. (1984) and Marchant & Higgins (1990) list breeding sites in the Ross Dependency (160°E-150°W) and…1 January, 1992
Previously, we reported on the discovery of fine structure in whistler data received on the ground at Halley, Antarctica. This structure was not apparent in conventional spectral analysis but was…1 January, 1992
We studied the distributions, abundances and interactions of macaroni penguins Eudyptes chrysolophus, Antarchc fur seals Arctocephalus gazella, and their zooplankton prey, m particular Antarctic krill Euphausia superba, near Bird Island,…1 January, 1992
References Citations Metrics Reprints & Permissions PDF Abstract The beaks of 9,994 cephalopods of 61 species, obtained mainly from chick regurgitations of wandering albatrosses (Diomedea exulans L.)…1 January, 1992 by Adrian Jenkins
We calculate the present ice budget for Antarctica from measurements of accumulation minus iceberg calving, run-off and in situ melting beneath the floating ice shelves. The resulting negative mass balance…Read more on Melting of ice shelves and the mass balance of Antarctica
1 January, 1992 by Philip Leat
A two-day meeting of the Tectonic Studies Group was held in London at the Geological Society on 3-4 October 1991, to consider relationships between continental extension, super continent break-up, magmatism…Read more on Magmatism and the causes of continental break-up
1 January, 1992 by Thomas Lachlan-Cope
Atmospheric temperature retrievals obtained by a simultaneous physical scheme and a statistical scheme are compared using data gathered over the Weddell Sea, Antarctica during January 1986. Ground truth data were…1 January, 1992
During the lactation period, female otariid seals alternate trips at sea to feed with visits ashore to nurse their pups. A female returning ashore must be able to recognize her…Read more on Fostering behaviour and milk stealing in Antarctic fur seals
1 January, 1992 by Robert Mulvaney
The east coast of the Antarctic Peninsula is strongly influenced by air masses that have traversed the Weddell Sea zone. A continuous record of annual-average values for δ18O, δD, Cl−…1 January, 1992 by Eric Wolff, Robert Mulvaney
Antarctic snow and ice contain very low concentrations of ions,Read more on The distribution of impurities in Antarctic ice
1 January, 1992
F-layer ionisation troughs are frequently observed in the sub-auroral and high-latitude ionospheres. We define the mid-latitude trough as the region of low plasma concentration at F-region altitudes that occurs near…1 January, 1992 by Eric Wolff, Robert Mulvaney
A technique, using Nuclepore polycarbonate membrane filters as a containing medium for very small volumes of ionic standard solutions, to produce homogeneous ice standards is described. The standards are suitable…Read more on Preparation of aqueous standards for low temperature x-ray microanalysis
1 January, 1992
A mathematical model of the ionosphere and plasmasphere that includes an eccentric dipole geomagnetic field has been constructed to model, in the first instance, whistler results at L = 2.5.…Read more on Seasonal and longitudinal effects on plasmaspheric tube content
1 January, 1992 by Paul Rodhouse
In the austral summers of 1986 and 1988–1989, 51 southern elephant seals (Mirounga leonina) at Husvik, South Georgia (54°10′S; 36°43′W), were stomach lavaged after chemical immobilization. Only cephalopod remains were…Read more on Cephalopod prey of the southern elephant seal, Mirounga leonina L.
1 January, 1992 by Paul Rodhouse
Cephalopod paralarvae and juveniles were sampled with RMT8 and Bongo nets during 2 cruises of the MV 'Falklands Protector' in the southwest Atlantic Ocean in October/November 1990 and 1991. Each…1 January, 1992
Simultaneous ground-based observations of narrowband and broadband VLF radio waves and of cloud-to-ground lightning were made at widely spaced locations during the 1987 Wave-Induced Particle Precipitation (WIPP) campaign, conducted from…1 January, 1992 by Howard Roscoe
The measurement of N2O5 by Evans [Appl. Opt. 25, 1866–1868 (1986)] contains several serious errors. A reanalysis of the published infrared spectra gives the more realistic error bar of ±45%.Read more on Observation of the 8-μm N2O5 thermal emission feature in the stratosphere: comment
1 January, 1992 by Howard Roscoe
In a new program which performs a Backus-Gilbert analysis of the output kernels from the input kernels of any hypothetical remote sensor, Conrath's method for calculating trade-off curves has been…1 January, 1992 by Mark Clilverd
The group delay times (tg) of whistler-mode waves generated by the NAA (f= 24.0 kHz) and NSS (f = 21.4 kHz) U.S. Navy transmitters and recorded at Faraday, Antarctica (L=…1 January, 1992
Palynomorph assemblages dominated by dinoflagellate cysts are described from seventeen samples from the Rabot Member of the Santa Marta Formation at Ekelöf Point, eastern James Ross Island, Antarctic Peninsula. Although…1 January, 1992 by Eric Wolff
Cadmium, copper, lead and zinc concentrations have been measured on a sequence of snow blocks covering 2 years’ accumulation at a site on the east coast of the Antarctic Peninsula.…Read more on Seasonal input of heavy metals to Antarctic snow
1 January, 1992
References Citations Metrics Reprints & Permissions Get access The standard of Antarctic maps in many of the world atlases on sale in the UK is reviewed and the…1 January, 1992 by Richard Horne
The excitation of SAR arcs requires the transfer of energy from the energetic storm-time ring current ions to tonal electrons located just inside the plasmapause. A recent observational study has…1 January, 1992
The LeMay Group of Alexander Island, Antarctic Peninsula, is a Mesozoic accretionary prism that was constructed during subduction of Pacific and proto-Pacific oceanic crust. In central Alexander Island, several distinct…1 January, 1992 by John Turner
An atmospheric transmittance model has been applied to Antarctic radiosonde ascents in order to examine the high-latitude normalized weighting functions (NWF) of the water vapour channels on the High Resolution…Read more on High-latitude moisture structure determined from HIRS water vapour imagery
1 January, 1992 by Jonathan Watkins
Length, sex and maturity stage of Antarctic krill Euphausia superba Dana occurring in discrete swarms were measured. Over a 14 d period 38 swarms were sampled in a small area…1 January, 1992
Syenogranites and monzogranites of Edward VII Peninsula, Marie Byrd Land, represent magmatism associated with continental rifting and the separation of New Zealand from W Antarctica in the mid-Cretaceous. These coarse-grained,…1 January, 1992
1. Plasma concentrations of urea, uric acid and total lipid were compared in pre- and late-fast breeding and moulting macaroni penguins (Eudyptes chrysolophus) to test the hypothesis that birds exhaust…Read more on Breeding and moulting fasts in macaroni penguins: Do birds exhaust their fat reserves?
1 January, 1992
Annual variation in return rate of breeding birds, mate and nest-site fidelity was studied in the resident Gentoo (Pygoscelis papua) and migratory Macaroni (Eudyptes chrysolophus) Penguin from 1986 to 1990…1 January, 1992
We studied diving patterns and performance (dive depth, duration, frequency and organization during the foraging trip) in relation to diet in nonbreeding Gentoo Penguins (Pygoscelis papua) over 59 days (involving…1 January, 1992 by Eric Wolff
The Antarctic ice sheet is the main sink for atmospheric pollution reaching the Antarctic atmosphere from other continents. The ice preserves a historical record of the atmosphere that can be…1 January, 1992
Thirty samples from two sections on south-western Humps Island, James Ross Basin, northern Antarctic Peninsula, contain moderately diverse dinoflagellate cyst assemblages deposited in shallow shelf, open marine conditions. Assemblages contain…Read more on Dinoflagellate cysts from the Marambio Group (Upper Cretaceous) of Humps Island
1 January, 1992 by Roger Worland, William Block
The ability of adults and larvae of two species of perimylopid beetles (Hydromedion sparsutum, Perimylops antarcticus) to survive sub-zero temperatures was studied at Husvik, South Georgia in summer during October–December…1 December, 1991
Seabirds of high latitudes in the North and South Atlantic (chiefly penguins, Procellariformes, alcids, shags, Gannet and Kittiwake) are compared (on absolute and energy-, mass- and time-specific scaled bases) in…Read more on Foraging economics and performance of polar and subpolar Atlantic seabirds
1 December, 1991 by Alistair Crame
One of the most important outcrops of uppermost Cretaceous (Campanian–Maastrichtian) sedimentary rocks in the southern high latitudes occurs within the James Ross Island group, northeastern Antarctic Peninsula. These rocks comprise…1 December, 1991
Geochemical and isotopic data are presented that suggest the existence of a large, Middle Jurassic subduction‐related magmatic province common to both the Antarctic Peninsula and southern South America. We argue…1 December, 1991
The population structure and transmission of Escherichia coli in a small group of individuals isolated for 26 weeks on an Antarctic base were studied by multilocus electrophoresis of eight enzymes…1 November, 1991
The burst precipitation of energetic electrons (≥40 keV), induced by interactions with lightning‐generated whistler mode waves, has been observed to cause phase and amplitude perturbations on subionospheric VLF signals (“Trimpi”…1 November, 1991 by Adrian Jenkins
Large‐scale oceanic circulation beneath Antarctic ice shelves is driven by the thenmohaline differences which result from mass and energy exchange at the ice‐ocean interface. Dense, saline waters are drawn underneath…Read more on A one-dimensional model of ice shelf-ocean interaction
1 November, 1991 by Robert Larter
Precise measurements of spreading rates on marine magnetic profiles collected to the west of the Antarctic Peninsula have enabled some consideration of the forces governing plate motion, since Antarctic—Phoenix motion…1 November, 1991 by Keith Makinson, Keith Nicholls
THE intimate thermal contact between the base of Antarctic ice shelves and the underlying ocean enables changes in climate to have a rapid impact on the outflow of ice from…1 November, 1991
Nitrogen assimilation was measured in two austral summers in the Scotia Sea around the island of South Georgia as well as the Bransfield Strait. Nitrate and ammonium assimilation was measured…29 October, 1991 by John Turner
1 October, 1991
We observed 195 multispecies feeding flocks of birds near Bird Island, South Georgia, between 4 February and 5 March in 1986. Up to 19 seabird species plus Antarctic fur seals…Read more on Observations of multispecies seabird flocks around South Georgia
1 October, 1991
During three days of quiet geomagnetic conditions in August 1988, both the EISCAT UHF radar and the NOAA digital ionospheric sounder (Dynasonde) were operated from 12:00 to 22:00 U.T. Sporadic-E…1 September, 1991
The Antarctic marine ecosystem contains low concentrations of a range of hydrocarbons, overwhelmingly biogenic in origin. The low natural levels of hydrocarbons and the small amount of local human activity…Read more on Hydrocarbons in the Antarctic marine environment
1 September, 1991
The horizontal and vertical distributions of cyanobacteria and algae on soil polygons on Signy Island were investigated. Soil chlorophyll concentrations increased from the centre to the edge of the polygons.…Read more on The spatial distribution of microalgae on Antarctic fellfield soils
1 September, 1991
During the austral summer of 1987/1988, three 24 h in situ primary productivity measurements were made at a nearshore sublittoral site on the east coast of Signy Island, Antarctica. The…1 September, 1991
The freshwater streams of James Ross Island share many of the features common to other Antarctic streams. There is a diel variation in temperature and discharge, which follows the daily…Read more on Freshwater stream ecosystems of James Ross Island, Antarctica
1 September, 1991
A 100‐m ice core from site G 15 (accumulation rate 0.1 m water yr−1, mean annual temperature −38°C) on the Mizuho plateau, Dronning Maud Land, East Antarctica, has been analysed…Read more on A continuous 770-year record of volcanic activity from east Antarctica
1 September, 1991
The Antarctic fellfield habitat is an extreme terrestrial environment in which the survival of organisms depends upon an ability to withstand both very low temperatures and severe water shortage. The…Read more on Water-loss and anhydrobiotic survival in nematodes of Antarctic fellfields
1 September, 1991
We have used observations of the group time delay and Doppler shift of ducted VLF whistler mode signals propagating near L = 2.5 to deduce the azimuthal component of the…Read more on Electric fields at L = 2.5 during geomagnetically disturbed conditions
1 September, 1991
Little is known about the aerial transport of microbes, plants and animals into and between Antarctic terrestrial and freshwater habitats. Isolation by the circumpolar Southern Ocean restricts propagules to three…Read more on Aerobiology and colonization in Antarctica — the BIOTAS Programme
1 August, 1991
A time-depth-temperature recorder provided a continuous record of diving by a female southern elephant seal in relation to water temperature for 27 days (1939 dives) after completion of moult. Mean…1 July, 1991
A model of the dynamics of magnetic storms is proposed which describes the effects of magnetospheric activity on irregularities at F layer heights for auroral and subauroral latitudes. For high…1 July, 1991
Aerosol samples were collected at a remote site near the east coast of the Antarctic Peninsula during the austral summer of 1984/85. Filter samples were analyzed for Al (as a…Read more on Concentrations and sources of metals in the Antarctic Peninsula aerosol
1 July, 1991
The seasonal pattern of the microphytobenthic community at a near-shore site on the east coast of Signy Island (60°43′S, 45°38′W), South Orkney Islands, was examined over a period of 18…1 July, 1991
A sediment core from Jane Basin, northern Weddell Sea, contains distinct bands, up to 3 cm thick, of well preserved diatom frustules, contrasting with the generally poor preservation of adjacent…Read more on Unusual diatom layers in upper pleistocene sediments from the northern Weddell Sea
1 July, 1991
The results are presented of a statistical study of the occurrence, strength, frequency and polarization characteristics of magnetic pulsations in the Pc3 frequency range (0.022–0.1 Hz) recorded at Halley, L…Read more on On the nature of Pc3 pulsations at L = 4 and their solar wind dependence
1 July, 1991 by Mark Clilverd
Whistler mode group delays observed at Faraday, Antarctica (65°S, 64°W) decrease after the onset of magnetic storms, and slowly recover to normal levels in 1 or 2 days. This is…Read more on Magnetic storm effects on the mid-latitude plasmasphere
1 June, 1991
(1) We investigated time allocation to parental care ashore and foraging at sea by lactating Antarctic fur seals at Bird Island, South Georgia, during 1988-89 and 1989-90 and related this…Read more on Time budgets and foraging characteristics of lactating Antarctic fur seals
1 June, 1991
A study has been made of vertical thermospheric winds in the vicinity of Halley, Antarctica (75.5°S, 26.8°W; L = 4.2). Strong downward winds, up to 50 m s−1, are frequently…Read more on Vertical thermospheric winds at the equatorward edge of the auroral oval
1 June, 1991
Ridge crest-trench interactions along continental destructive plate margins may result in the development of slab-free windows beneath the continental margin. Slab windows were generated at various locations along the Pacific…Read more on Relation between alkalic volcanism and slab-window formation
1 June, 1991 by Andrew Clarke, Peter Ward
Resting metabolic rate(V ˙ O 2[rest] ) (V˙O2[rest]) was measured in demersal stages of the teleostNotothenia neglecta Nybelin from the South Orkney Islands, Antarctica, from 1985 to 1987. The relationship…1 June, 1991 by Ed King
The British Antarctic Survey has commenced a programme of multichannel seismic reflection work over the Antarctic continental ice sheet and surrounding ice shelves. This is part of an integrated geophysical…Read more on Effectiveness of different shooting techniques in Antarctic firn