Found 14089 items
1 January, 2001 by Roger Worland, William Block
The effect of different culture methods, cold acclimation and desiccation on the supercooling point (SCP), the melting point (MP) of fluids and the quantity of water freezing (osmotically active water)…Read more on Experimental studies on cold survival of enchytraeid cocoons
1 January, 2001 by Richard Phillips
This study combines conventional dietary assessment with stable isotope techniques to describe Great Skua (Stercorarius skua) diet. Stable carbon and nitrogen isotope ratios in feathers of Great Skua chicks collected…1 January, 2001
The adaptation of Imaging Doppler Interferometry (IDI) to the dynasonde deployed at the Bear Lake Observatory (41.9°N, 111.4°W) in northeastern Utah enables the routine measurement of mesospheric dynamics. Influenced by…1 January, 2001
We investigated foraging behavior of Wandering Albatrosses (Diomedea exulans) breeding at South Georgia to assess how sex and season-specific foraging patterns relate to provisioning performance. We estimated Wandering Albatross chicks…1 January, 2001 by Peter Convey, William Block
Body-water content of field-fresh samples of the springtail, Cryptopygus antarcticus Willem (Collembola, Isotomidae) was measured at monthly intervals over 11 years (1984–1995) at Signy Island, in the maritime Antarctic. A…1 January, 2001 by Roger Worland, William Block
Ice nucleation was studied in field-fresh and acclimated (4°C without food for 11–20 days) samples of the springtail Cryptopygus antarcticus Willem (Collembola, Isotomidae) at Rothera Research Station, Adelaide Island on…1 January, 2001 by Iain Staniland
The study aimed to test the utility of instruments deployed on marine mammals for measuring physical oceanographic variation and, using this method, to examine temperature variation in the coastal waters…Read more on Measurement of ocean temperatures using instruments carried by Antarctic fur seals
1 January, 2001
1 This study examined the changing status of the marine ecosystem at the island of South Georgia (Southern Ocean) using up to 27 variables measured over 22 years from three…Read more on Monitoring a marine ecosystem using responses of upper trophic level predators
1 January, 2001
Multi-frequency acoustic data (18, 38 and 120 kHz) were collected in conjunction with pelagic trawl sampling for gelatinous macrozooplankton during a cruise to the Namibian Benguela in September 1999. Sampling…Read more on Acoustic observations of jellyfish in the Namibian Benguela
1 January, 2001
The Autonomous Underwater Vehicle (AUV) Autosub-1 made observations of the sea surface with an upward-looking echosounder during fish surveys in the vicinity of Shetland and Orkney (North Sea) in July…1 January, 2001 by Andrew Clarke
The seasonal pattern of food intake and tissue energy status was measured over a 2 year period for two populations of the common Antarctic echinoid Sterechinus neumayeri living on contrasting…1 January, 2001
Seasonal changes in feeding activity, metabolic rate and major tissue energy concentrations of the infaunal bivalve Laternula elliptica were monitored over a 12 degrees month period in relation to phytoplankton…1 January, 2001 by Andrew Clarke
Many benthic marine invertebrates exhibit a seasonal cycle in activities such as feeding, growth and reproduction. In temperate regions, this seasonality is typically correlated with coincident cycles in photoperiod, temperature…1 January, 2001 by Lloyd Peck
Oxygen consumption (MO2) and ammonium excretion rates were recorded monthly over 2 yr for the regular Antarctic echinoid Sterechinus neumayeri to investigate metabolic activity in relation to seasonal food limitation…1 January, 2001
Bathymetric and seismic data show that the southernmost segment of the EastScotia Ridge (segment E9) is anomalous in its curved plan form, and in the presence of a large axial…1 January, 2001
The population structure of black-browed (Thalassarche melanophris and T. impavida) and grey-headed (T. chrysostoma) albatrosses was examined using both mitochondrial DNA (mtDNA) and microsatellite analyses. mtDNA sequences from 73 black-browed…1 January, 2001
The discovery of gullies and debris aprons raises the question of the existence of aqueousenvironments on Mars in recent geological times and its astrobiological implications. Three cases of such environments…Read more on Recent aqueous environments in Martian impact craters: an astrobiological perspective
1 January, 2001
A single fossil leaf of Nothofagus from CRP-3 drillhole in the Victoria Land Basin provides further evidence for woody vegetation in the Tertiary of East Antarctica. The plicate vernation of…1 January, 2001
Coniferous foliage from the Albian of AlexanderIsland, Antarctica, is assigned to the Araucariaceae, Podocarpaceae, and Taxodiaceae based on attached or associated fertile remains. Araucarian foliage represented by Araucaria alexandrensis sp.…1 January, 2001
Whistler-mode waves propagating to ground stations along geomagnetic-field-aligned paths provide powerful tools for investigating bulk motions of the magnetospheric plasma and thus the corresponding convection electric fields. Natural whistlers from…1 January, 2001
New data suggest that the eastern margin of the Argentine Precordillera terrane comprises Grenvillian basement and a sedimentary cover derived from it that were together affected by Middle Ordovician deformation…1 January, 2001 by John King
Calculated surface fluxes from seven surface layer parameterizations are verified against 45 months of observations from Halley, Antarctica, with a temporal resolution of 1 h. The surface layer parameterizations are…1 January, 2001
Observations of recent volcanic eruptions in Iceland and detailed studies of sub-glacially erupted deposits and the interaction of lava and pyroclastic flows with snow and ice have provided important new…Read more on Study of volcano/ice interactions gains momentum
1 January, 2001
Recently, the paradigm that the dynamic magnetosphere displays sandpile-type phenomenology has been advanced, in which energy dissipation is by means of avalanches which do not have an intrinsic scale. This…1 January, 2001
The characterization of global energy storage and release in the coupled solar wind-magnetosphere system remains one of the fundamental problems of space physics. Recently, it has been realised that a…Read more on Avalanching and self organised criticality, a paradigm for geomagnetic activity?
1 January, 2001 by Gareth Chisham, Michael Pinnock
In the high-latitude dayside ionosphere, the movement of the HF radar spectral width boundary (SWB) provides a good proxy for the movement of the open-closed field line boundary around magnetic…1 January, 2001 by Andrew Clarke
Marine organisms in Antarctica live in an environment which exhibits variability in physical processes over a wide range of temporal scales, from seconds to millennia. This time scale tends to…1 January, 2001 by Mark Clilverd
During the total solar eclipse observed in Europe on August 11, 1999, measurements were made of the amplitude and phase of four VLF transmitters in the frequency range 16–24 kHz.…Read more on Total solar eclipse effects on VLF signals: observations and modeling
1 January, 2001
Astrobiology has recently been feted as a science for the twenty-first century. Founded as a science in the Soviet Union in 1953, its recent manifestation has been accompanied by a…1 January, 2001
Ultraviolet radiation is an important natural physical influence on organism function and ecosystem interactions. The UVradiation fluxes in extraterrestrial environments are substantially different from those experienced on Earth. On Mars,…1 January, 2001
The Martianpolar ice caps are regions of substantial scientific interest, being the most dynamic regions of Mars. They are volatile sinks and thus closely linked to Martian climatic conditions. Because…Read more on Martian polar expeditions: problems and solutions
1 January, 2001
In the Archean era (3.8–2.5 Ga ago) the Earth probably lacked a protective ozone column. Using data obtained in the Earth’s orbit on the inactivation of Bacillus subtilis spores we…1 January, 2001
The input of nutrients into arctic polar deserts, aided by some physical processes, can result in localized areas of high biological productivity--"micro-oases." We examined the vegetation cover, and microbial and…1 January, 2001
During July 2000 we used an electronic personal dosimeter (X-2000) and a biological dosimeter (Deutsches Zentrum für Luft- und Raumfahrt: Biofilm) to characterize the UV radiation exposure of arctic field…1 January, 2001
In this paper, numerical weather prediction analyses from four major centers are compared—the Australian Bureau of Meteorology (ABM), the European Centre for Medium-Range Weather Forecasts (ECMWF), the U.S. National Centers…1 January, 2001
The recent history of global initiatives to reduce seabird bycatch in longline fisheries is reviewed, highlighting in turn the activities of environmental and industry non-governmental organizations (NGOs), national governments, and…Read more on Off the hook? Initiatives to reduce seabird bycatch in longline fisheries
1 January, 2001 by Adrian Jenkins, David Vaughan
We present newly acquired airborne radar data showing ice thickness and surface elevation for Pine Island Glacier, Antarctica. These data, when combined with earlier measurements, suggest the presence of a…Read more on Investigations of an ‘ice plain’ in the mouth of Pine Island Glacier, Antarctica
1 January, 2001 by Alistair Crame
There is evidence from the fossil record to suggest that latitudinal gradients in taxonomic diversity may be time-invariant features, although almost certainly not on the same scale as that seen…Read more on Taxonomic diversity gradients through geological time
1 January, 2001
Early Paleozoic orogenesis has been recognized along the southern African (Saldanian orogeny) and East Antarctic (Ross orogeny) sectors of the Gondwana paleo- Pacific margin. However, the absence of a contemporaneous…1 January, 2001
Since the early 1990s, the Cape Roberts Project has been working to document, through sediment drilling, the proximal record of Antarctic ice sheet history and climate for the southwestern part…1 January, 2001
A total of eighteen species of marine ostracods, in at least twelve genera, have been recovered from Early and Late Oligocene glacio-marine sediments from boreholes CRP-3 and CRP-2/2A in the…1 January, 2001 by Adrian Jenkins, Andy Smith, David Vaughan, Hugh Corr, Keith Makinson, Keith Nicholls
Rutford Ice Stream is in many ways a typical Antarctic outlet glacier. Constrained by a subglacial-bed trough to the east of the Ellsworth Mountains, it drains an area of 49,000…1 January, 2001 by Mark Clilverd
There are two distinctly different causes of phase and amplitude perturbations of subionospheric VLF transmissions (termed “Trimpis”): (1) ionization enhancement in the ionospheric D region due to whistler-induced electron precipitation…1 January, 2001
Mackerel icefish (Cllanzpsocephal[~gsz rnnnvi) are widespread on the South Georgia shelf, Antarctica, and have been fished commercially since the early 1970s. They are known to feed predominantly on krill. An…Read more on Variations in condition indices of mackerel icefish at South Georgia from 1972 to 1997
1 January, 2001
Historical information on the distribution of spawning and larval mackerel icefish (Champsocephalus gunnari) within CCAMLR Subarea 48.3 (South Georgia and Shag Rocks) is assessed. This is considered alongside new data…Read more on Spawning locations of mackerel icefish at South Georgia
1 January, 2001
Silicified gymnosperm trunks usually more than 30 cm in diameter and several metres in length occur abundantly in the lower part of the mid-AptianCerroNegroFormation, which crops out on ByersPeninsula, LivingstonIsland,…1 January, 2001
The leaf longevity and seasonal timing of leaf abscission within a plant community is closely related to climate, a phenomenon referred to as leaf phenology. In this paper the leaf…Read more on Leaf phenology of some mid-Cretaceous polar forests, Alexander Island, Antarctica
1 January, 2001
The biodiversity and terrestrial ecology of the Late Albian Triton Point Formation (Fossil Bluff Group), Alexander Island, Antarctica is analysed to improve our understanding of polar biomes during the mid-Cretaceous…1 January, 2001
The botanical identity and facies distribution of fossil charcoal is described from Middle to Late Cenomanian (90–94 Ma) fluvial to estuarine units at Pecínov quarry, near Prague, Czech Republic. Braided…1 January, 2001 by Adrian Fox
Automatic digital elevation model (DEM) generation has become an established technique within mapping agencies. This paper assesses the effectiveness of automatic DEM generation using area-based matching for glaciated terrain in…1 January, 2001
It has been suggested previously that the presence and abundance of indigenous species have a marked influence on the likelihood of invasion of a community. It has also been suggested…1 January, 2001 by Lloyd Peck
The metabolism of a coastal mysid population ŽPraunus flexuosus. from the West Solent South England. has been studied in different seasons winter, spring and summer.. Metabolic responses to copper 0,…Read more on Effects of copper exposure on the metabolism of the mysid Praunus flexuosus
1 January, 2001 by Lloyd Peck
The reproductive biology, in response to temperature, season and copper, of a coastal population of opossum shrimps (Crustacea: Mysidacea) was measured. The reproductive pattern for Praunus flexuosus at Keyhaven (west…Read more on Reproduction, seasonality, and copper toxicity in the coastal mysid Praunus flexuosus
1 January, 2001
Microsatellites were used to conduct an analysis of paternity of Antarctic fur seals (Arctocephalus gazella) from Bird Island, South Georgia. At most, only 28% of pups at our study site…1 January, 2001
To assess the biological implications of ozone depletion over the Antarctic Peninsula, the ultraviolet (UV) regime of two Antarctic cyanobacterial communities (composed of Leptolyngbya sp. and Phormidium sp.) was manipulated…Read more on Tolerance of Antarctic cyanobacterial mats to enhanced UV radiation
1 January, 2001 by Paul Rodhouse
Acoustic survey methods are now widely used for stock assessments of finfish, both those with and without swimbladders, but their application to squid stocks has been limited in the past,…Read more on Investigations of squid stocks using acoustic survey methods
1 January, 2001
Twenty-four macaroni penguins (Eudyptes chrysolophus) from three groups, breeding males (N=9), breeding females (N=9) and moulting females (N=6), were exercised on a variable-speed treadmill. Heart rate (fH) and mass-specific rate…Read more on Heart rate and rate of oxygen consumption of exercising macaroni penguins
1 January, 2001
XRD analysis of weathering rinds on ocean-deposited ice rafted clasts provide a snapshot of palaeo-terrestrial conditions prevailing at the time of rind formation. Investigation of weathering rinds found on some…1 January, 2001 by Richard Phillips
Seabirds may be able to increase their foraging efficiency by learning the whereabouts of predictable sources of prey and returning repeatedly to these locations. The occurrence of such foraging area…1 January, 2001
Magnetic properties of bulk sediment samples taken from three cores from the Scotia Sea, Antarctica were determined using a fully-automated variable field translation balance. Fine-grained detrital magnetite is identified as…Read more on Magnetic properties of Upper Quaternary sediments from the Scotia Sea, Antarctica
1 January, 2001
Although Sims Island (73°17′S/78°33′W), a bedrock peak in Carroll Inlet on the English Coast of eastern Ellsworth Land (Fig. 1), had previously been observed and photographed from the air (e.g.…1 January, 2001
Lower Cretaceous conglomeratic strata exposed on southern Sobral Peninsula were deposited on a deep-marine apron in the back-arc Larsen Basin close to its faulted boundary with the Antarctic Peninsula magmatic…1 January, 2001
The Pedersen Formation includes conglomerate-dominated successions exposed on Pedersen Nunatak (142 m thick) and southern Sobral Peninsula (750–1000 m thick). As re-defined here, it also includes mudstone and sandstone in…1 January, 2001 by Roger Worland, Peter Convey
The hygropreference of adult Cryptopygusantarcticus and Alaskozetesantarcticus was investigated over 2 h at 5, 10 and 20°C, along humidity gradients (9–98% RH) established by means of different salt solutions. Two…1 January, 2001 by Richard Hindmarsh, Richard Hindmarsh
Marine ice sheets with mechanics described by the shallow-ice approximation by definition do not couple mechanically with the shelf. Such ice sheets are known to have neutral equilibria. We consider…Read more on Dynamical processes involved in the retreat of marine ice sheets
1 January, 2001 by Dominic Hodgson
The Rauer Islands contain more than fifty shallow lakes and small ephemeral ponds. Despite their proximity to the Vestfold fills - one of the most diverse and intensively studied lake…Read more on Limnology and biology of saline lakes in the Rauer Islands, eastern Antarctica
1 January, 2001 by Dominic Hodgson
Lake sediments in the Larsemann Hills contain a great diversity ofbiological and physical markers from which past environments can be inferred. In order to determine the timing of environmental changes…Read more on Were the Larsemann Hills ice-free through the Last Glacial Maximum?
1 January, 2001 by Adrian Jenkins
Much of the Antarctic coastline comprises large, floating ice shelves, beneath which waters from the open ocean circulate. The interaction of the seawater with the base of these ice shelves…1 January, 2001 by Mervyn Freeman, Richard Horne
We present anewsimulationcode for electrostatic waves in one dimension which uses the Vlasovequation to integrate the distribution function and Ampère'sequation to integrate the electric field forward in time. Previous Vlasovcodes…1 January, 2001
Reproductive pentoxylalean material from the Albian Triton Point Formation, Fossil Bluff Group of Alexander Island, Antarctica is the youngest record of this group globally. Leaves are referred to Taeniopteris daintreei…Read more on Palaeoecology and taxonomy of Pentoxylales from the Albian of Antarctica
1 January, 2001
A psychrophilic, aerobic bacterium designated A2iT was isolated from marine sediment recovered from shallow waters surrounding Adelaide Island, Antarctica (67S 34H S, 68S 07H W). The organism exhibited xylanolytic and…1 January, 2001 by Robert Mulvaney
In 1997 a 121 m ice core was retrieved from Lomonosovfonna, the highest ice field in Spitsbergen, Svalbard (1250 m a.s.l.). Radar measurements indicate an ice depth of 126.5 m,…1 January, 2001
Within the global context, Antarctica has a key role to play in understanding long-term change in the upper atmosphere, both because of its isolation from the rest of the world…Read more on Antarctica’s role in understanding long-term change in the upper atmosphere
1 January, 2001
In the mesosphere and lower thermosphere the contrasts between the Antarctic and Arctic regarding both the energy inputs and the consequent dynamics, energetics and chemistry mean that comparative polar observations…Read more on Antarctic-Arctic contrasts – key pointers to mesospheric dynamics and energetics
1 January, 2001
The mesosphere and lower thermosphere have long suffered from their inaccessibility to research balloons and satellites alike. As a result, basic knowledge about this central region of the atmosphere is…1 January, 2001 by Adrian Jenkins
Upper boundary conditions for numerical models of the ocean are conventionally formulated under the premise that the boundary is a material surface. In the presence of an ice cover, such…1 January, 2001
Analysis of the Batoka Basalts exposed in the Zambezi Gorge some 40 km east of Victoria Falls characterizes them as high Fe, moderately high Ti, and low K, P, and…