Showing 11862 items
1 January, 2000 by Jonathan Watkins
Much of the distribution range of Antarctic krill, Euphausia superba, is covered by permanent or seasonal sea ice. Sea ice extent has been implicated as a major factor affecting reproductive…Read more on Effects of sea ice cover on the swarming behaviour of Antarctic krill,Euphausia superba
1 January, 2000
On Bird Island, South Georgia, albatrosses (n = 140), penguins (n = 100), and fur seals (n = 206) were sampled for Campylobacter jejuni. C. jejuni subsp. jejuni was recovered…1 January, 2000
1 The population density, diversity and productivity of the microbial plankton in an oligotrophic maritime Antarctic lake were studied for a 15-month period between December 1994 and February 1996. 2…Read more on Temporal plankton dynamics in an oligotrophic maritime Antarctic lake
1 January, 2000
Cetricycas antarcticus gen. et sp. nov. occurs in the Late Coniacian to Campanian Lachman Crags Member of the Santa Marta Formation, Marambio Group, James Ross Island, Antarctica. The petrified trunk…Read more on A petrified cycad trunk from the Late Cretaceous of the Larsen Basin, Antarctica
1 January, 2000
A macroflora from John Peaks, Powell Island, contains Sagenopteris nilssoniana, Cladophlebis oblonga, Brachyphyllum sp., Elatocladus confertus, and Sphenopteris sp. The macroflora is best correlated with the Botany Bay Group flora,…1 January, 2000
Publication of the Composite gazetteer of Antarctica by the SCAR Working Group on Geodesy and Geographic Information is a major milestone in the evolution of Antarctic toponymy. It has taken…1 January, 2000 by Gareth Chisham, Michael Pinnock
Poleward‐moving line‐of‐sight velocity “flow bursts” have been observed in the cusp by two southern hemisphere SuperDARN HF radars with overlapping fields‐of‐view. This has allowed the estimation of unambiguous two‐dimensional velocity…1 January, 2000 by Gareth Chisham, Michael Pinnock
We present data from conjugate SuperDARN radars describing the high-latitude ionosphere's response to changes in the direction of IMF By during a period of steady IMF Bz southward and Bx…1 January, 2000 by Andrew Clarke
1. We have examined large-scale geographical patterns in species richness for continental shelf bryozoan assemblages in the North Atlantic. Bryozoans are common and often abundant benthic organisms, but they have…1 January, 2000
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ∼106 km2 and total as much as…Read more on The state and future of Mars polar science and exploration
1 January, 2000 by Mark Clilverd
Unusually low whistler mode group delay times are observed by VLF Doppler receivers at both Faraday, Antarctica, and Dunedin, New Zealand, following magnetic storms. These are typically caused by plasmaspheric…1 January, 2000 by Michael Pinnock
The antiparallel merging hypothesis states that reconnection takes place on the dayside magnetopause where the solar and geomagnetic fields are oppositely directed. With this criterion, we have mapped the predicted…Read more on The ionospheric footprint of antiparallel merging regions on the dayside magnetopause
1 January, 2000
We aim to identify the important steps in the evolution of the ecosystem approach to management under the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR). The first…1 January, 2000 by Peter Convey
The South Sandwich Islands are an isolated maritime Antarctic volcanic island arc 550-600km south-east of South Georgia. The terrestrial biology of the islands, with emphasis on the unique habitats associated…Read more on The terrestrial micro-arthropod fauna of the South Sandwich Islands
1 January, 2000 by Dominic Hodgson, Helen Peat, Peter Convey
Aim To carry out as comprehensive a survey as practicable of the flora (higher plants, mosses, liverworts, lichens, basidiomycete fungi and diatoms) of the isolated, volcanically active, South Sandwich Islands…1 January, 2000 by Helen Peat, Peter Convey
This paper documents the previously undescribed terrestrial fauna (mites, nematodes, tardigrades) and flora (liverworts, mosses and lichens) of Marion Nunataks, Charcot Island (69°45'S 075°15'W). Species diversity in all groups is…1 January, 2000 by Roger Worland, Peter Convey
In studies of three common, freezing susceptible, Antarctic microarthropods, the springtail Cryptopygus antarcticus and the mites Alaskozetes antarcticus and Halozetes belgicae, we report (i) the consequences on cold tolerance of…Read more on Refining the risk of freezing mortality for Antarctic terrestrial microarthropods
1 January, 2000 by Roger Worland, Peter Convey
Free-living microbivorous nematodes become numerically dominant in Antarctic terrestrial faunas as environmental conditions become more severe, while also reaching very high levels of abundance in moist, vegetated habitats. Nematodes have…Read more on Survival of freezing by free-living Antarctic soil nematodes
1 January, 2000 by Alistair Crame
A major new inventory of living marine Bivalvia (Mollusca) is based on 29 regional faunas. These again pick out strong latitudinal and longitudinal gradients in taxonomic diversity, but there are…1 January, 2000
In a previous study at South Georgia, carnivory was invoked as a cause of high polyunsaturated fatty acid (PUFA) content of Antarctic krill, Euphausia superba. To examine this, krill were…1 January, 2000 by Lloyd Peck
A complete energy balance equation is calculated for the Antarctic octopus Pareledone charcoti at 0°C. Energy used in respiration, growth, and excretion of nitrogenous and faecal waste, was recorded along…Read more on Energy balance and cold adaptation in the octopus Pareledone charcoti
1 January, 2000 by Paul Rodhouse
In the summer of 1995/96, 25 southern elephant seals, Mirounga leonina, were stomach lavaged at Stranger Point, King George Island, South Shetland Islands. Cephalopod remains were present in 72% of…1 January, 2000
Bipolarity, the presence of a species in the high latitudes separated by a gap in distribution across the tropics, is a well-known pattern of global species distribution. But the question…1 January, 2000
Biomolecules, such as the productive and protective pigments of photosynthetic organisms, are good biomarkers in extreme Antarctic deserts as analogues of early Mars. Laser Raman technology at long wavelengths which…1 January, 2000
A review is made of stratigraphical, geochemical and palaeogeographical data from the northern Antarctic Peninsula and the Southern Ocean for Late Mesozoic-Early Cenozoic times. Clay mineral and S/total organic C…1 January, 2000 by Peter Convey, Sandra McInnes, Sandra McInnes
A small collection of samples from terrestrial and fresh-water habitats on Deception Island in the Maritime Antarctic South Shetland archipelago yielded 14 invertebrate taxa, including four species, which are new…1 January, 2000 by Roger Worland, William Block
DSC analysis was performed at three points in the cryopreservation process on encapsulated-dehydrated meristems of Ribes ciliatum. Meristems were excised from shoots pre-treated with either sucrose or glucose, encapsulated in…1 January, 2000
The Raman spectrum of the photoprotective pigmentscytonemin found in cyanobacterial sheaths has been obtained for the first time. Its skeletal structure is extensively conjugated and unique in nature. Detailed molecular…1 January, 2000
Spawning by Antarctic fish is generally considered to be seasonal and restricted to a brief period during the autumn and winter. Arising from this it has been assumed that the…Read more on Inter-annual variation in the gonad cycle of the mackerel icefish
1 January, 2000
Silicified conifer woods are very common in the mid-Cretaceous (LateAlbian, 100 Ma) Triton Point Member of the Neptune Glacier Formation (Fossil Bluff Group), SE AlexanderIsland, Antarctica. These occur as up…1 January, 2000
A method is outlined in which woods produced by deciduous and evergreen coniferopsids may be distinguished from one another on the basis of a quantitative analysis of growth ring anatomy.…1 January, 2000
Growth rings in modern conifer woods were quantitatively analysed to investigate the relationship between leaflongevity and the markedness of the growth ring boundary. Five conifer species exhibiting a wide range…1 January, 2000 by Andrew Clarke
Environmental seasonality is a critical factor in structuring polar marine ecosystems. The extensive data now available on the lipids of Arctic and Antarctic euphausiids show that all species are characterised…Read more on Lipids, trophic relationships, and biodiversity in Arctic and Antarctic krill
1 January, 2000
The precarious condition of the world's fisheries is making ever-greater demands of the scientific assessment of fish stocks. Traditional assessments that rely on commercial catch statistics can have major shortcomings1…1 January, 2000
Interpretation of an airborne magnetic data compilation containing a key, new survey, together with re-tracked satellite gravity data from the WeddellSeaembayment (WSE), West Antarctica, suggests Rift–Rift–Rift triplejunction formation at the…Read more on Relics of a complex triple junction in the Weddell Sea embayment, Antarctica
1 January, 2000
The Oligocene to Quaternary succession encountered in CRP-2/2A is divided into twelve recurrent lithofacies (some of which have been subdivided further), reflecting a range of marine, glacimarine and possibly subglacial…Read more on Facies analysis and sequence stratigraphy of CRP-2/2A, Victoria Land basin, Antarctica
1 January, 2000 by Howard Roscoe
A recently published analysis of slant columns of NO2 observed at twilight at 45°S has identified trends of about 5%/decade between 1980 and 1998. This is twice the trend in…Read more on Possible causes of stratospheric NO2 trends observed at Lauder, New Zealand
1 January, 2000 by Mervyn Freeman
Magnetospheric cavity modes can decay through various loss processes. Energy leakage across the magnetopause is one such process that is commonly neglected. Here we consider what the actual effect of…Read more on Effect of magnetopause leakage on the lifetime of magnetospheric cavity modes
1 January, 2000 by Mervyn Freeman
In this paper we examine the claim that the power law distribution of burst lifetimes in the AE index is evidence that the magnetosphere is a Self‐Organized Critical (SOC) system.…1 January, 2000 by Mervyn Freeman
We calculate the probability density functions P of burst energy e, duration T, and interburst interval τ for a known turbulent system in nature. Bursts in the Earth-Sun component of…1 January, 2000 by Lloyd Peck
Copper toxicity was tested on a coastal population of the mysid Praunus flexuosus (Müller) from Southampton Water (Southern England) under winter and summer conditions. Ten-day toxicity tests were performed on…1 January, 2000 by Andrew Wood
We satellite-tracked the foraging trips of males and females of the 2 sibling species of giant petrels, Macronectes halli and M. giganteus, breeding sympatrically at Bird Island (South Georgia, Antarctica),…1 January, 2000 by Andrew Wood
Giant petrels (Macronectes spp.) are the most sexually dimorphic of all seabirds. We used satellite-tracking and mass change during incubation to investigate the influence of sexual size dimorphism, in terms…1 January, 2000 by Eugene Murphy, Peter Ward
A field comparison of an optical plankton counter (OPC) and a Longhurst-Hardy Plankton Recorder (LHPR) was undertaken around the sub-Antarctic island of South Georgia during austral spring, 1997, to investigate…1 January, 2000 by Andrew Wood, Richard Phillips
We used satellite telemetry to examine the foraging ranges, feeding locations and travel speeds of 17 chick-rearing gannets Morus bassanus from the Bass Rock, SE Scotland. Regurgitates indicated that birds…1 January, 2000
Evidence is sought for El Niño–Southern Oscillation (ENSO) teleconnections in the South Pacific extratropical atmospheric circulation and in seasonal temperatures in the west Antarctic Peninsula (WAP) during austral winter. Emphasis…1 January, 2000
Sprites, a form of brief luminous discharge in the upper atmosphere above a thunderstorm, were observed and imaged on two video cameras in Australia's Northern Territory. These were the first…Read more on Sprite observations in the Northern Territory of Australia
1 January, 2000
Loligo gahi were collected from bottom trawl samples taken around the Falkland Islands on both commercial and research vessels from January 1994 to November 1995. Commercial samples were taken from…1 January, 2000
The Larsen Basin developed in Jurassic times as a result of continental rifting during the early stages of Gondwana break‐up. Lower‐?Upper Jurassic non‐marine sedimentary and volcanic rocks constitute a syn‐rift…1 January, 2000 by Roger Worland, Peter Convey
The hygropreference of adult Onychiurus arcticus (Tullberg) was investigated over 2 h at 0, 10 and 20°C, along humidity gradients (12–98% RH) established using different salt solutions. At all temperatures…1 January, 2000
On Bird Island, South Georgia, a new strain of Chlamydophila abortus was detected in one Brown skua out of 37 specimens from six different seabird species. Phylogenetic analysis of thernpB…1 January, 2000 by Richard Hindmarsh, Richard Hindmarsh
Many glacier beds are anisotropic, by which is meant that the dominant wavelengths are different in the two map-plane directions. A largely unexplored consequence of Nye-Kamb sliding theory is the…1 January, 2000 by Gareth Marshall
An examination of 50 years of the National Centers for Environmental Prediction (NCEP)–National Center for Atmospheric Research (NCAR) reanalysis from 1949 to 1998 reveals that significant spurious trends occur in…1 January, 2000
Fourier Transform laser Raman spectroscopy was used to generate diagnostic spectra for pigments and biodegradative calcium oxalate in situ in two yellow-pigmented species of the lichen genus Acarospora from contrasting…1 January, 2000
The primary obstacles to the collection of oceanographic data are the limitations of sampling i n time and in three-dimensional space. Ship-board surveys are well designed for detailed sampling at…Read more on Living probes into the marine environment – apex predators as oceanographic platforms
1 January, 2000 by Richard Horne
It has been suggested that highly anisotropic electron pancake distributions are the result of pitch angle diffusion by electrostatic electron cyclotron harmonic (ECH) and whistler mode waves in the equatorial…1 January, 2000 by Richard Horne
We investigate the propagation, growth, and decay of fast magnetosonic waves in the Earth's magnetosphere which are believed to contribute to proton heating up to energies of a few hundred…Read more on Proton and electron heating by radially propagating fast magnetosonic waves
1 January, 2000
We present a new type of equation to describe the growth patterns of procellariiform seabirds and other species whose chicks characteristically lose mass towards the end of the rearing period.…Read more on Chick growth in albatrosses: curve fitting with a twist
1 January, 2000
We compared the parental division of labour and the pattern and rate of parental provisioning by two sympatric species of albatross of similar mass and breeding timetable but differing in…1 January, 2000 by Anna Jones
Because investigations of PAN at higher southern latitudes are very scarce, we measured surface PAN concentrations for the first time in Antarctica. During the Photochemical Experiment at Neumayer (PEAN'99) campaign…1 January, 2000 by Anna Jones, Eric Wolff
Measurements were made of NO and NO2, in controlled experiments to investigate their production from snow. Throughout a diurnal cycle, measurements were made of ambient air and air from inside…Read more on Speciation and rate of photochemical NO and NO2 production in Antarctic snow
1 January, 2000
The Dynasonde is a digital ionosonde which measures the amplitude and phase of radio echoes reflected from the ionosphere. In addition to the frequency and virtual range of each echo,…Read more on Dynasonde observations of electron concentration gradients above Tromsø
1 January, 2000 by Dominic Hodgson
Lake-sediment cores from Heywood and Sombre Lakes on Signy Island (South Orkney Islands), Antarctica, have yielded a conformable radiocarbon chronology for the Holocene and a high-resolution record of environmental change.…1 January, 2000
Boreholes in the large, extinct Antarctic Neogene pectinid Zygochlamys anderssoni suggest that this scallop was preyed upon by a large predatory muricid gastropod impossibly a Trophon species). The holes occur…1 January, 2000 by Michael Pinnock
This paper deals with an evolution of the electric field in the dayside auroral and equatorial ionosphere during asubstorm on July 16, 1995. A southward turning of the IMF detected…1 January, 2000 by Ed King
The Weddell Sea embayment is central to reconstructions of the West Antarctic region of Gondwana. Some reconstructions represent this area as a pre-break-up component, the Filchner block, defined by the…1 January, 2000 by Anna Jones, John Turner, Thomas Lachlan-Cope
During 1994/95 a UK Overseas Development Administration (now Department for International Development - DFID) funded project was undertaken to predict ozone amount over Punta Arenas in southern Chile. A low-cost…Read more on A pilot study for predicting ozone amounts for the general public in southern Chile
1 January, 2000 by Howard Roscoe, Jonathan Shanklin
Several years of total ozone measured from space by the ERS-2 GOME, the Earth Probe TOMS, and the ADEOS TOMS, are compared with high-quality ground-based observations associated with the Network…1 January, 2000
Strontium isotope stratigraphy was used to date 16 discrete horizons within the CRP-2/2A drillhole. Reworked Quaternary (1 January, 2000
The growth rates of heterotrophic nanoflagellates (HNAN), mixotrophic cryptophytes, dinoflagellates and ciliates in field assemblages from Ace Lake in the Vestfold Hills (eastern Antarctica) and Lakes Fryxell and Hoare (McMurdo…1 January, 2000 by Richard Hindmarsh, Richard Hindmarsh
When predicting the deformation of the Earth under surface loads, most models follow the same methodology, consisting of producing a unit response that is then con-volved with the appropriate surface…1 January, 2000 by Philip Leat
Segment E2 is situated in the back-arc East Scotia Ridge. The segment is unusual in that it has an axial topographic high underlain by a seismically imaged melt lens. The…Read more on Magma supply in back-arc spreading segment E2, East Scotia Ridge
1 January, 2000 by Philip Leat, Teal Riley
An ultramafic lamprophyre dyke is described from the otherwise tholeiitic Ferrar magmatic province of Antarctica. We report an Ar-Ar age of 183 ± 2.2 Ma for the dyke, indistinguishable from…1 January, 2000 by Howard Roscoe
A three‐dimensional chemical‐transport model of the stratosphere has been used to study the 1996 austral winter and spring. Both the model and ozonesonde measurements show that ozone depletion associated with…Read more on Model and measurements show Antarctic ozone loss follows edge of polar night
1 January, 2000
New bathymetric and magnetic anomaly data from the Phoenix Ridge, Antarctica, show that extinction of all three remaining segments occurred at the time of magnetic chron C2A (3.3 ± 0.2…Read more on Autopsy on a dead spreading center: The Phoenix Ridge, Drake Passage, Antarctica
1 January, 2000
Aerobic endospore-forming bacteria were isolated from soils taken from active fumaroles on Mount Rittmann and Mount Melbourne in northern Victoria Land, Antarctica, and from active and inactive fumaroles on Candlemas…1 January, 2000
New swath bathymetric, multichannel seismic and magnetic data reveal the complexity of the intersection between the extinct West Scotia Ridge (WSR) and the Shackleton Fracture Zone (SFZ), a first-order NW-SE…Read more on Tectonics of an extinct ridge-transform intersection, Drake Passage (Antarctica)
1 January, 2000
Measurements of blowing snow particle concentration from the second Stable Antarctic Boundary Layer Experiment (STABLE 2) are presented. The measurements, made at Halley Station (75.6 degreesS, 26.7 degreesW) throughout the…Read more on Profile measurements of blowing snow at Halley, Antarctica
1 January, 2000
Oribatid mites are typically terrestrial, though many species of Ameronothroidea are marine intertidal. Marine ameronothroids are cosmopolitan with genera being endemic to the Holarctic, sub-Antarctic, or equatorial Indo-Pacific and tropical…1 January, 2000 by Gareth Marshall
In this study numerical weather prediction model data are utilized to examine the precipitation regime at Thurston Island (TI) (∼72°S, 99°W) in West Antarctica. This region was chosen because the…1 January, 2000 by Gareth Marshall
Fifty years of monthly mean sea level pressure (MSLP) data from the NCEP/NCAR reanalysis (hereinafter NNR) are validated against station observations in the extratropical South Pacific and West Antarctica. The…1 January, 2000
Satellite-derived maps of surface UV irradiance are currently limited by their poorly assessed accuracy. Here we use an extensive data set of ground-based spectral measurements from two Alpine sites to…Read more on Uncertainties in satellite-derived estimates of surface UV doses
1 January, 2000
Cyanobacteria and eukaryotic algae, together with bacteria and fungi, are known to be primary colonizers of mineral soils throughout Antarctica. Their species diversity and soil coverage were studied in 18…