Found 14089 items
1 January, 1998 by Howard Roscoe
A new method for retrieving the vertical profile of NO2 from ground-based measurements is applied to four months of measurements made at Aberdeen (57°N) during part of SESAME from November…1 January, 1998 by Eugene Murphy
In view of the wide range of estimates for the total primary production for the Southern Ocean south of the Subantarctic Front—current estimates range from 1.2 to 3.5 Gtonne C…1 January, 1998 by Eugene Murphy
The Southern Ocean is the largest of the high-nutrient, low-chlorophyll (HNLC) regions of the world ocean. Phytoplankton production fails to utilise completely the pool of inorganic nutrients in the euphotic…1 January, 1998
On the continental rise west of the Antarctic Peninsula there are nine large mounds interpreted as sediment drifts, separated by turbidity current channels. Drift 7 is 150 km long, 70…1 January, 1998
Within the Scotia Sea, the axis of the Antarctic Circumpolar Current (ACC) is geographically confined, and sediments therefore contain a record of palaeo-flow speed uncomplicated by ACC axis migration. We…Read more on Quaternary history of the Antarctic Circumpolar Current: evidence from the Scotia Sea
1 January, 1998 by Sandra McInnes, Sandra McInnes
The tardigrade faunas of six Arctic sites (Canadian Axel Heiberg I., east and west coasts of Greenland, Iceland, Svalbard, Novaya Zemlya and the Russian Taimyr Peninsula) form, with those of…Read more on The origin of Arctic terrestrial and freshwater tardigrades
1 January, 1998
From a detailed study of a 500 km transect in the Sierras Pampeanas, central-west Argentina, two pre-Silurian tectono-magmatic episodes are recognized and defined, each culminating in micro-continental collisions against the…Read more on Early evolution of the Proto-Andean margin of South America
1 January, 1998
A detailed study of the pre-Silurian geology of the Sierras de Córdoba, Eastern Sierras Pampeanas, is used to define the sequence of magmatic and metamorphic events during the Pampean orogeny.…1 January, 1998 by John King
Large amplitude, isolated, wave-like phenomena have been observed in the lowest 40 m of the strongly stably stratified atmospheric boundary layer overlying a coastal Antarctic ice shelf. The waves only…Read more on Observations of solitary waves in the stable atmospheric boundary layer
1 January, 1998
A discriminant function using simple carapace measurements corretly determined the sex of 87% of male and 89% of female Antarctic krill Euphausia superba. This facilitated the use of sex-specific regression…Read more on Determining the sex of Antarctic krill Euphausia superba using carapace measurements
1 January, 1998 by Alistair Crame
The Lagrelius Point Formation from its type area in north-west James Ross Island, Antarctica has yielded dinoflagellate cysts indicative of an earliest Aptian age. Reworked palynomorphs presumed to be from…Read more on The age of the base of the Gustav Group in the James Ross Basin, Antarctica
1 January, 1998
Historically, the term polar patch was used to describe isolated regions of enhanced 630 nm emission observed in the polar cap. In recent years, signatures from other instruments, such as…1 January, 1998
Whilst it is well-accepted that short-duration changes to the Interplanetary Magnetic Field (IMF) and solar wind cause high-latitude ionospheric transients observed by magnetic, optical and radar techniques, a coherent explanation…Read more on Ionospheric signatures of magnetopause pocesses
1 January, 1998 by Paul Rodhouse
Chiroteuthis veranyi (Férussac, 1835) (Cephalopoda: Chiroteuthidae) from South Georgia is described from material collected during the British Antarctic Survey's Offshore Biological Programme. The material closely resembles C. veranyi from elsewhere…1 January, 1998 by Eugene Murphy, Paul Rodhouse
Artificial selection pressures imposed by fisheries can impact population structure in the short term and drive evolution of life-history traits in the long term. In exploited squid populations the short…1 January, 1998 by Paul Rodhouse
The king penguin Aptenodytes patagonicus is a sub-Antarctic species that feeds primarily on mesopelagic fish and cephalopods in the vicinity of the Antarctic Polar Front (APF). We examined the cephalopod…Read more on Cephalopod predation by the king penguin Aptenodytes patagonicus from South Georgia
1 January, 1998 by Paul Rodhouse
The coleoid cephalopods (cuttlefish, squid and octopus) arose from their shelled ancestors during the late Devonian; they diversified in the Jurassic but did not radiate substantially until the Tertiary. Since…Read more on Physiological progenesis in cephalopod molluscs
1 January, 1998
Laser-based Fourier-Transform Raman spectroscopy (FTRS) has been used to identify in situ compounds of ecophysiological significance in diverse field-fresh Antarctic cryptoendolithic microbial communities. FTRS does not disrupt the community and…1 January, 1998
Modern ionosondes make almost simultaneous measurements of the time rate of change of phase path in different directions and at different heights. By combining these 'Doppler' measurements and angles of…Read more on Plasma drift estimates from the Dynasonde: comparison with EISCAT measurements
1 January, 1998 by Peter Ward
Instantaneous measurements of moulting and growth of the early copepodite stages of 2 species of Antarctic copepod, Rhincalanus gigas and Calanoides acutus, were made at 4 regions around South Georgia…1 January, 1998 by Peter Ward
An inter-comparison of three commonly reported methods for estimating the stage duration of copepods was made on Calanus helgolandicus from both wild and laboratory-reared populations. These three methods have not…Read more on Moulting rates of Calanus helgolandicus: an inter-comparison of experimental methods
1 January, 1998
Summary: Antarctica was the focus of numerous exploring and commercial expeditions by different nations during the 19th and early part of the 20th centuries and today it is a truly…1 January, 1998
On King George Island during latest Oligocene/earliest Miocene time, submarine eruptions resulted in the emplacement of a small (ca. 500 m estimated original diameter) basalt lava dome at Low Head. The…1 January, 1998
Detrital modes for the sand-size fraction in 24 samples from the CRP- 1 drillcore arc described. Most samples are largely composcd of quart7.o-feldspathic detritus sourced dominantly from Palaeozoic granitoids and…1 January, 1998
This paper describes amplitude modulations in the frequency range 0–500 mHz of ELF/VLF (0.5–4.0 kHz) radio wave power recorded throughout 1993 and 1995 at Halley and South Pole stations, Antarctica,…Read more on Periodic and quasiperiodic ELF/VLF emissions observed by an array of Antarctic stations
1 January, 1998
The VLF database from Halley station, Antarctica, has been searched, and prominent examples of discrete emissions are presented. Risers, fallers, quasiconstant tones, and upward and downward hooks are all common.…Read more on Numerical simulation of VLF risers, fallers, and hooks observed in Antarctica
1 January, 1998
This paper presents results from the first systematic survey of VLF wave activity at Halley, Antarctica (76 °S, 27 °W, L = 4.3). Beginning in 1971, the peak, average and…1 January, 1998 by Andy Smith, David Vaughan
Level-line surveys at a number of sites on the Antarctic Peninsula since the early 1970s have shown a lowering of the ice surface elevation in areas where the climate is…1 January, 1998
Optically derived upper thermospheric wind and temperature data, collected at Antarctic stations at South Pole (L = 14), Mawson (L = 9.3), and Halley (L = 4.6), and averaged over…1 January, 1998
An investigation was carried out on the recently discovered ‘giant’ extra large (XL) form of the squid Sthenoteuthis oualaniensis from the Arabian Sea. The sample consisted of 2 males, which…1 January, 1998 by Andrew Clarke
The reproductive and larval biology of the common Antarctic cushion-star Odontaster validus Koehler (Echinodermata: Asteroidea) were studied in a shallow-water population at Signy Island in the maritime Antarctic. The gonad…1 January, 1998 by Lloyd Peck
The effects of temperature on development and viability were measured at 14 levels between -2{deg}C and +3{deg}C on embryos of two asteroids (Odontaster validus and Odontaster meridionalis) and an echinoid…1 January, 1998 by William Block
Oribatid mites are an ancient group of cosmopolitan terrestrial arthropods with limited trans-oceanic dispersal abilities. They provide an opportunity to answer questions concerning the role played by Gondwanaland, either as…1 January, 1998 by Eric Wolff
A detailed dielectric profiling (DEP) conductivity profile (σ∞) measured in the 6 m of the basal silty ice sequence from the Greenland Ice Core Project (GRIP) ice core (Summit, Central…1 January, 1998 by Eugene Murphy, Philip Trathan
Data from individual hauls carried out by vessels operating in the South Georgia krill fishery between 1994 and 1996 were examined and a range of descriptive measurements reflecting the fishery…Read more on Analysis of haul data from the South Georgia krill fishery
1 January, 1998 by Eugene Murphy, Philip Trathan
Macaroni penguins are the main avian consumer of Antarctic krill in the vicinity of South Georgia. The largest breeding colonies occur on small offshore islands to the northwest of the…1 January, 1998 by Gareth Marshall, John Turner, Thomas Lachlan-Cope
Daily precipitation fields and annual means from the European Centre for Medium-range Weather Forecasts re-analysis exercise are used to examine the distribution and variability of precipitation across the Antarctic Peninsula.…1 January, 1998 by Gareth Marshall, John Turner, Thomas Lachlan-Cope
Satellite imagery of the Antarctic Peninsula, Bellingshausen Sea, and Weddell Sea region, together with operational meteorological analyses, are used to investigate the development, tracks, and structure of synoptic-scale weather systems…1 January, 1998 by Anna Jones, Howard Roscoe
Comparisons of total column ozone measurements from Dobson, Brewer and SAOZ instruments are presented for the period 1990 to 1995 at seven stations covering the mid- and the high northern…1 January, 1998
The metazoan meiobenthos was investigated in an Antarctic coastal sediment (Factory Cove, Signy Island, Antarctica). The fine sands contained much higher abundances compared to major sublittoral sediments worldwide. Classified second…1 January, 1998
Ar–Ar laserprobe dating suggests that in western Palmer Land, plutons associated with a curvilinear belt of positive magnetic anomalies along the Pacific margin of the Antarctic Peninsula, the Pacific Margin…1 January, 1998 by David Vaughan
A digital elevation model (DEM) of the surface of the Antarctic ice sheet is compared with a simple two-dimensional ice-flow model to illuminate gross distortions (>500 m) of the ice-surface…1 January, 1998
The capture of 52 specimens of the cirrate octopod Grimpoteuthis glacialis (Robson, 1930), of dorsal mantle length 20-165 mm during a 1996 trawling survey near the Antarctic Peninsula allowed the…1 January, 1998 by Paul Rodhouse
This study is based on the large, mostly unreported collections of histioteuthids that have accumulated since the family was first revised by Voss in 1969. Of primary importance are the…1 January, 1998 by Eric Wolff, Robert Mulvaney
Continuous year round records of atmospheric sea-salt concentrations have been recovered at three coastal Antarctic stations (Halley, Dumont D'Urville, and Neumayer) at temporal resolutions typically between 1 day and 2…1 January, 1998 by Eric Wolff
Records of atmospheric nitrate were obtained by year-round aerosol sampling at Neumayer and Dumont D'Urville stations, located in the Atlantic and Pacific sector of coastal Antarctica, respectively. Where possible, evaluation…Read more on Atmospheric near-surface nitrate at coastal Antarctic sites
1 January, 1998 by Michael Pinnock
Results of an HF radar study of convection during an extended quiet solar wind interval on March 10 1997 are presented. After thirty hours during which the solar wind met…1 January, 1998
Seasonal haul-out patterns and diet of individually marked leopard seals (Hydrurga leptonyx) were investigated at Bird Island, South Georgia during the 1983–96 winters. A total of 2956 leopard seal sightings…1 January, 1998 by Richard Horne
The dominant features of Jovian whistlers observed by Voyager 1 in the inner cold torus around RJ ≈ 5.3 are studied using the technique of ray tracing with an offset…Read more on Cold torus whistlers: An indirect probe of the inner Jovian plasmasphere
1 January, 1998 by Richard Horne
The dispersion of unducted lightning-generated whistlers observed by Voyager 1 in the warm torus around density peaks at L = 5.7 and L = 5.9 are analyzed using the HOTRAY…1 January, 1998 by Peter Ward
Egg hatching times were determined at a range of temperatures for four species of commonly occurring Antarctic copepods. At a given temperature the eggs of Rhincalanus gigas took longest to…1 January, 1998
New Pb, Nd, and Sr isotope data are presented for geochemically similar, ∼1.1–1.2 Ga, granitoids and tonalitic‐granitic orthogneisses from Antarctica, southern Africa, and the Falkland Islands and adjoining plateau, areas…Read more on Pb, Nd, and Sr isotope mapping of Grenville‐age crustal provinces in Rodinia
1 January, 1998 by Philip Leat
Mafic dykes of the Antarctic Peninsula continental-margin arc are compositionally diverse, comprising calc-alkaline (dominant), shoshonite, tholeiite, and OIB-like varieties. Their compositions give information about different mafic magma sources tapped during…1 January, 1998 by Michael Pinnock
We have found flow burst features in the nightside ionosphere that are thought to be the ionospheric signature of distant tail reconnection. These are observed to form just prior to…Read more on Localized activation of the distant tail neutral line just prior to substorm onsets
1 January, 1998 by Jonathan Watkins
Antarctic krill, Euphausia superba Dana, a major component in the southern ocean food web, typically occur in aggregations that range from small, discrete swarms and schools through to layers and…Read more on Layers of Antarctic krill, Euphausia superba : are they just long krill swarms?
1 January, 1998 by Mark Clilverd
We report measured levels of very low frequency (VLF) radio noise at ∼10 kHz, due to lightning sferics, observed at Halley Station, Antarctica (76°S, 27°W) between 1971 and 1996. The…1 January, 1998 by William Block
Soil warming experiments were conducted in tundra heath and polar semi-desert soils at the High Arctic location of Ny-Alesund, West Spitsbergen, Svalbard, The warming treatment resulted in an 8-10% increase…1 January, 1998 by Andrew Clarke
At first sight, the life-history strategies adopted by Antarctic fish appear to be a paradox. The majority of fish species are demersal and inhabit the peri-Antarctic islands that are isolated,…Read more on Development, dispersal and recruitment: A paradox for survival among Antarctic fish
1 January, 1998 by Roger Worland
The mechanism by which the freeze susceptible Arctic collembolan Onychiurus arcticus survives winter temperatures of −25°C in the field is not fully understood but exposure to sub-zero temperatures (e.g. −2.5°C)…1 January, 1998
Plankton samples were collected from 10 depths at 25 stations spaced at intervals of about 4° of latitude along a transect from the British Isles to the Falkland Islands. Four…Read more on Picoplanktonic community structure on an Atlantic transect from 50°N to 50°S
1 January, 1998 by William Block
Amylolytic activity was measured in whole body homogenates of High Arctic (Onychiurus arcticus) and temperate (Protaphorura armata) springtails (Collembola: Onychiuridae) in the temperature range 5–55°C. A pH of ca. 8…1 January, 1998 by Claire Waluda
A Geographic Information System (GIS) was used to test hypotheses regarding the spatial distribution of the squid Loligo forbesi and Loligo vulgaris vulgaris in the northern North-East Atlantic during the…1 December, 1997 by Peter Convey
1. 1. Features of life history strategies of Antarctic terrestrial invertebrates are reviewed and compared with the predictions of two widely-used general life history models. 2. 2. Many features observed…1 December, 1997 by Richard Horne
We have used 1-year's data from the recently installed Magnetometer Array for Cusp and Cleft Studies (MACCS) in Arctic Canada and from two stations of the developing “conjugate” array of…1 December, 1997
Perturbations in the geomagnetic field at the Earth's surface can result from variations in the neutral wind field in the lower thermosphere through dynamo action in the interfused ionospheric E…1 December, 1997
The mackerel icefish (Champsocephalus gunnari) is a prominent member of the coastal fish fauna of the Seasonal Pack-Ice Zone and the islands north of it. Separated into a number of…1 December, 1997
The dispersal of algae and cyanobacteria at three Antarctic fellfield sites was investigated using microscopic and culture analysis of samples from active and passive air samplers Intersite variation in the…Read more on Airborne dispersal of antarctic terrestrial algae and cyanobacteria
1 December, 1997 by William Block
Cold-resistance studies of marine invertebrates have concentrated on intertidal sedentary organisms, which are often subjected to subzero air temperatures in winter. Mobile rock pool inhabitants have been rarely studied because…1 December, 1997 by Alistair Crame, Teal Riley
New exposures of fossiliferous sedimentary rocks at Cape Framnes, Jason Peninsula (65°57′S, 60°33′W) are assigned to the Middle–Late Jurassic Latady Formation of the south-eastern Antarctic Peninsula region. A sequence of…1 December, 1997 by Philip Leat
Compositions and distributions of mafic dykes in the Antarctic Peninsula continental arc show that tapping of several mantle sources was tectonically controlled. In the Cretaceous to Tertiary, between 135 Ma…1 December, 1997
Antarctic cartographers face many challenges. They are required to prepare accurate maps of a remote and dangerous environment in support of science programmes, logistic operations, and search and rescue activities.…1 December, 1997
The chrysophyte stomatocyst flora from 36 moss samples from Stromness Bay area on the subantarctic island of South Georgia is decribed, using both light and scanning electron microscopy. A total…1 December, 1997
A first ichthyoplankton spatial distribution survey was carried out in the coastal zone of Adelie Land in Antarctica in January-February 1996. Thirty three stations were investigated in a bay of…1 November, 1997
A large ultra-oligotrophic Antarctic freshwater lake, Crooked Lake, was investigated between January 1993 and November 1993. The water column supported a small phytoplankton community limited by temperature, nutrient availability and,…1 November, 1997
The digital ionospheric sounder, or dynasonde, located at the British Antarctic Survey's research station at Halley, Antarctica, has recently been operated as an imaging Doppler interferometer (IDI). The implementation of…1 November, 1997
Well-documented present-day distributions of stable water isotopes (HDO and H218O) show the existence, in middle and high latitudes, of a linear relationship between the mean annual isotope content of precipitation…Read more on Validity of the temperature reconstruction from water isotopes in ice cores
1 November, 1997 by Peter Convey
Aerobiological studies were conducted for >1 year using arrays of rotorod samplers at three sites on Signy Island, South Orkney Islands, maritime Antarctic. Spores of five bryophyte taxa were identified,…Read more on Dispersal of moss propagules on Signy Island, maritime Antarctic
1 November, 1997
At the northern edge of the Weddell Gyre, Antarctica, fine-grained sediments accumulate beneath eastward-flowing Weddell Sea Bottom Water. We report on sediment trap material and core tops from four sites,…1 November, 1997 by Eric Wolff
High-resolution continuous profiles were obtained on the Greenland Ice Core Project (GRIP) ice core using two different electrical methods. After correction for temperature and density, the electrical conductivity method (ECM)…1 October, 1997
A retrospective analysis of accidents involving snowmobiles experienced by members of the British Antarctic Survey between 1989 and 1996 revealed 37 injured individuals (or 1.9% of new consultations). The mean…1 October, 1997
Using a hierarchy of climate models together with observations from gridded analyses, I examine the atmosphere-only and coupled ocean-atmosphere variability in the general circulation for the region south of 40 °S.…Read more on Variability in annual mean circulation in southern high latitudes