Found 13639 items
1 January, 2003 by Andrew Clarke
Temperature affects everything that an organism does. Although we have an increasingly sophisticated understanding of evolutionary adaptation to temperature at the molecular level for some cellular processes, we still know…Read more on Costs and consequences of evolutionary temperature adaptation
1 January, 2003 by Andrew Clarke
This review of polar marine ecosystems covers both the Arctic and Antarctic, identifying the major threats and, where possible, predicting their possible state(s) in 2025. Although the two polar regions…Read more on Polar marine ecosystems: major threats and future change
1 January, 2003 by Mervyn Freeman
We discuss how the ideal formalism of computational mechanics can be adapted to apply to a noninfinite series of corrupted and correlated data, that is typical of most observed natural…1 January, 2003 by Mark Clilverd, Michael Rose
[1] Two independent ground-based experiments and two satellite-borne experiments are used to interpret the changes in plasmaspheric composition at the same point in space during moderate geomagnetic activity on 22…Read more on In situ and ground-based intercalibration measurements of plasma density at L = 2.5
1 January, 2003 by Mark Clilverd
[1] The longest data sets available for estimating thermospheric temperature trends are those from ground-based ionosondes, which often begin during the International Geophysical Year of 1957, close to a solar…Read more on Residual solar cycle influence on trends in ionospheric F2-layer peak height
1 January, 2003 by Mark Clilverd
We consider the likely levels of solar activity in 2100 by analysing the previous history of long-term solar and geomagnetic activity indices. We make use of superposed periods of similar…1 January, 2003
Biological dosimeters made from a monolayer of Bacillus subtilis spores were used to investigate the penetration of ultraviolet radiation into some widespread terrestrial microbial microhabitats at polar latitudes: at Mars…1 January, 2003
The establishment of a permanent human scientific presence at the Martian poles requires the identification of a strategy for growth, from localized field parties to a permanent polar infrastructure. Using…1 January, 2003
We examined the environmental stresses experienced by cyanobacteria living in endolithic gneissic habitats in the Haughton impact structure, Devon Island, Canadian High Arctic (75° N) and compared them with the…Read more on Polar endoliths – an anti-correlation of climatic extremes and microbial diversity
1 January, 2003
Impact structures are a rare habitat on Earth. However, where they do occur they can potentially have an important influence on the local ecology. Some of the types of habitat…Read more on The impact crater as a habitat: effects of impact processing of target materials
1 January, 2003 by Mark Belchier
1 January, 2003 by Martin Collins
The systematics and distribution of the cirrate octopod genus Grimpoteuthis in the north-east Atlantic are reviewed. Three new species are described and Grimpoteuthis wuelkeri (Grimpe, 1920) is redescribed. A new…1 January, 2003
[1] During the period 1968-1999, the character of circum-Antarctic anomalies in sea level pressure, sea ice edge, and sea surface temperature changed substantially. An Antarctic Circumpolar Wave (ACW) is only…Read more on Long-term variation of the Antarctic Circumpolar Wave
1 January, 2003 by Peter Convey
The simplicity of maritime Antarctic terrestrial ecosystems, combined with rapid changes in several environmental variables, creates a natural laboratory probably unparalleled worldwide in which to study biological consequences of climate…Read more on Maritime Antarctic climate change: signals from terrestrial biology
1 January, 2003 by Helen Peat, Peter Convey, William Block
Abiotic features of Antarctic terrestrial habitats, particularly low temperatures and limited availability of liquid water, strongly influence the ecophysiology and life histories of resident biota. However, while temperature regimes of…Read more on Soil arthropods as indicators of water stress in Antarctic terrestrial habitats?
1 January, 2003 by Peter Fretwell
Placenames in Antarctica are uniquely complex. Antarctica’s distinctive political environment results in a situation where many national bodies confer names, but until recently there has been no coordination of this…1 January, 2003 by Anna Jones, Eric Wolff
[1] Laboratory experiments were conducted to determine the wavelength and temperature dependence of NO and NO2 release from Antarctic snow. This photochemically driven process has been observed during recent field…1 January, 2003 by Peter Convey
Over 300 species of insect (including Collembola) are recorded from Svalbard. These include 11 species of Lepidoptera, the majority of which are occasional summer immigrants (Coulson and Refseth 2003). Those…Read more on A high-Arctic population of Pyla fusca (Lepidoptera, Pyralidae) on Svalbard?
1 January, 2003
[1] The baroclinic transport of the Antarctic Circumpolar Current (ACC) above 3000 m through Drake Passage is 107.3 +/- 10.4 Sv and has been steady between 1975 and 2000. For…Read more on Transport and variability of the Antarctic Circumpolar Current in Drake Passage
1 January, 2003
The Neptune Range of the Pensacola Mountains, East Antarctica, exposes a record of Early Palaeozoic to Early Mesozoic polyphase deformation along the former East Antarctic margin of Gondwana that is…1 January, 2003 by Teal Riley
Large mafic sills in the Ahlmannryggen region of western Dronning Maud Land were intruded into partially lithified sediments of the mid-Proterozoic Ritscherflya Supergroup. Clastic sedimentary dykes intruding the thick mafic…1 January, 2003 by Richard Phillips
Recent taxonomic revisions of the Wandering Albatross sensu lato has resulted in four separate species, the rarest of which is the Tristan Albatross (Diomedea dabbenena). We present the first detailed…1 January, 2003 by Adrian Jenkins, Hugh Corr, Keith Nicholls
We have collected polarimetric ice sounding radar data on Brunt, George VI and Ronne ice shelves using a vector network analyser as a continuous wave step-frequency radar. Being a wideband…1 January, 2003
Specimens of a late Bajocian to early Callovian isocrinid assigned to Pentacrinites cf. P. californicus (Clark), and specimens collected by Hikuroa in 1999–2000, are described as a new species of…1 January, 2003
Lichens in Antarctic habitats are subjected to environmental extremes, including UVB radiation, desiccation and low temperatures, as well as to rapid fluctuations in these. Lichens synthesise a variety of chemical…1 January, 2003 by Dominic Hodgson
The Fourier transform-Raman spectra of two lacustrine sediment cores from Antarctic sites are reported. The Lake Hoare specimens were predominantly calcium carbonate, quartz and β-carotene, with chlorophyll and calcium sulphate…1 January, 2003
Project Leader, Antarctic Astrobiology, British Antarctic Survey, Cambridge 1946–2002 David Donaldson Wynn-Williams, born 16th July, 1946, in West Kirby, Cheshire, UK and Founding Editor of the International Journal of Astrobiology,…Read more on Guest editorial to special issue dedicated to David D. Wynn-Williams
1 January, 2003
The vital UV-protective and photosynthetic pigments of cyanobacteria and lichens (microbial symbioses) that dominate primary production in Antarctic desert ecosystems auto-fluoresce at short-wavelengths. A long wavelength (1064 nm) near infra-red…1 January, 2003
The FT-Raman and infrared vibrational spectra of some important lichen compounds from two metabolic pathways are characterised. Key biomolecular marker bands have been suggested for the spectroscopic identification of atranorin,…1 January, 2003
The Raman and infrared spectra of the UV-radiation protectant parietin extracted from Xanthorialichen species are reported and vibrational assignments made of key features which are important for the characterisation of…Read more on Molecular spectroscopic studies of lichen substances 1: parietin and emodin
1 January, 2003
The vital ultraviolet- (UV-) protective and photosynthetic pigments of cyanobacteria and lichens (microbial symbioses) that dominate primary production in Antarctic desert ecosystems auto-fluoresce at short wavelengths. We therefore use a…1 January, 2003
In this paper, in this edition of the Journal commemorating the life and work of David Wynn-Williams, we consider approaches to the astrobiological investigation of Mars. We provide a brief…Read more on Astrobiological instrumentation for Mars – the only way is down
1 January, 2003
In Part 1 of this paper, we presented a phased approach to the development of a Mars pole human-inhabited research station modelled on those in the terrestrial polar regions. To…Read more on The human exploration of the Martian poles Part 2 – support technologies
1 January, 2003
We provide a scientific rationale for the astrobiological investigation of Mars. We suggest that, given practical constraints, the most promising locations for the search for former life on Mars are…Read more on Why Raman spectroscopy on Mars? – a case of the right tool for the right job
1 January, 2003
Semi-continuous, linear accumulations of poorly-sorted debris are present on the surface of the remnant Larsen-A Ice Shelf, Antarctic Peninsula. These accumulations form a complex of debris bands extending parallel to…Read more on Supraglacial debris along the front of the Larsen-A Ice Shelf, Antarctic Peninsula
1 January, 2003 by Mervyn Freeman
An extraordinary powering of the magnetosphere by the solar wind occurred in a 3-hour burst early on May 4 when the IMF was very intense and pointed south (≈-35 nT;…1 January, 2003 by Mervyn Freeman
We study large-scale magnetospheric disturbances elicited by the May4, 1998 high speed stream by modeling the Dst and studying records from 4 meridional magnetometer chains covering key local time sectors.…1 January, 2003 by David Pearce
The polar desert is one of the most extreme environments on Earth. Endolithic organisms can escape or mitigate the hazards of the polar desert by using the resources available in…1 January, 2003 by Robert Larter
The Antarctic Climate Evolution (ACE) project is a new international research initiative to study the climate and glacial history of Antarctica by linking climate and ice sheet modeling studies with…Read more on Antarctic Climate Evolution (ACE) Research Initiative
1 January, 2003 by Mervyn Freeman
Two competing paradigms of the response of ionospheric convection to changes in the interplanetary magnetic field are synthesized into the common framework of the expanding-contracting polar cap (ECPC) model in…1 January, 2003
Bransfield Strait, a narrow active rift with three submarine basins, separates the South Shetland Islands from northern Antarctic Peninsula. Volcanism in Bransfield Strait commenced prior to 0.75 Ma and continues,…1 January, 2003
Heart rate (fH), abdominal temperature (Tab) and diving depth were measured in thirteen free-ranging breeding female macaroni penguins. Measurement of these variables allowed estimation of the mass-specific rate of oxygen…1 January, 2003 by Huw Griffiths, Alistair Crame, Katrin Linse
Databases and Geographical Information Systems are becoming increasingly popular tools for biogeographic analysis. The reliability of the analysis depends on the accuracy of the entered data and the ability to…1 January, 2003 by Hilmar Gudmundsson
Transmission of basal variability to a glacier surface is investigated using analytical models for a linearly viscous medium. The three-dimensional transient response of the surface to both bedrock undulations and…Read more on Transmission of basal variability to a glacier surface
1 January, 2003 by Hilmar Gudmundsson
The amplitude ratio between surface and bedrock topography has been predicted to depend strongly on the ratio of deformational velocity to mean basal sliding velocity. Observations made prior to and…1 January, 2003 by Lloyd Peck
Aquarium-based observations of the feeding behaviour of the Antarctic muricid gastropod Trophon longstaffi over a 3-year period revealed that individuals were capable of feeding on both bivalve (Laternula elliptica and…1 January, 2003 by Philip Leat, Robert Larter
The East Scotia Ridge, situated in the South Atlantic, is the back-arc spreading centre to the intra-oceanic South Sandwich arc. Samples from the ridge show a wide diversity in erupted…1 January, 2003 by Roger Worland, Peter Convey
The thermal preferences of Alaskozetes antarcticus (Acari, Cryptostigmata) and Cryptopygus antarcticus (Collembola, Isotomidae) were investigated over 6 h within a temperature gradient (−3 to +13 °C), under 100% relative humidity…1 January, 2003 by Richard Hindmarsh, Richard Hindmarsh
Two aspects of thermal coupling with bedrock are considered: the coupled time-dependent problem of co-evolving temperatures in lithosphere and ice; and the influence of basal topography on steady temperature distribution…Read more on Thermomechanical coupling of ice flow with the bedrock
1 January, 2003
We compiled a global data set of copepod in situ weight-specific fecundity and growth rates, together with measurements of their body weights, and the chlorophyll a and temperature of the…1 January, 2003
We present the most extensive study to date of globally compiled and analysed weight-specific growth rates in marine epi-pelagic invertebrate metazoan zooplankton. Using specified selection criteria, we analyse growth rates…Read more on A synthesis of growth rates in marine epipelagic invertebrate zooplankton
1 January, 2003
We study scaling in fluctuations of the geomagnetic indices (AE, AU, and AL) that provide a measure of magnetospheric activity and of the ϵ parameter which is a measure of…1 January, 2003 by Dominic Hodgson
With the exception of the diatoms, little is known of the extinction, colonization, and succession of marine floras during glacial cycles. Here we study both morphological and biochemical fossils in…1 January, 2003
Although mammalian mating systems are classically characterized in terms of male competition and polygyny, it is becoming increasingly apparent that alternative male strategies and female choice may play important roles.…1 January, 2003
Populations of the only two flowering plants native to the Antarctic have recently increased in number and size possibly due to climate warming. We have undertaken a preliminary study of…Read more on Populations of Antarctic hairgrass (Deschampsia antarctica) show low genetic diversity
1 January, 2003 by Adrian Jenkins
We applied a modified version of the Miami isopycnic coordinate ocean general circulation model (MICOM) to the ocean cavity beneath the Ross Ice Shelf to investigate the circulation of ocean…Read more on Modelling the ocean circulation beneath the Ross Ice Shelf
1 January, 2003
Diving marine predators have been used to collect data on ocean temperature, but salinity measurements have not previously been incorporated into predator-borne data loggers. Here we present data on initial…Read more on Salinity sensors on seals: use of marine predators to carry CTD dataloggers
1 January, 2003 by Richard Horne
We investigate the pitch angle distributions of 0.15-1.58 MeV electrons observed during the 9-15 October 1990 storm measured by the Combined Release and Radiation Effects Satellite (CRRES) spacecraft. This storm…1 January, 2003 by Richard Horne
There are two main theories for the origin of diffuse auroral electron precipitation: precipitation by electrostatic ECH waves and precipitation by whistler mode waves. Here we analyze a case event…1 January, 2003
Kongsfjorden and Krossfjorden are two ice-proximal fjords on the western coast of Spitsbergen which have been surveyed using multibeam bathymetry, sub-bottom profiling and gravity coring. Central and outer Kongsfjorden is…1 January, 2003 by Kevin Hughes
This study demonstrates for the first time that faecalcoliform bacteria can survive airborne transfer in Antarctica, but are unlikely to survive for prolonged periods following deposition due to environmental stresses.…Read more on Aerial dispersal and survival of sewage-derived faecal coliforms in Antarctica
1 January, 2003 by Kevin Hughes
Factors affecting fecal microorganism survival and distribution in the Antarctic marine environment include solar radiation, water salinity, temperature, sea ice conditions, and fecal input by humans and local wildlife populations.…1 January, 2003 by Kevin Hughes
The majority of coastal Antarctic stations release untreated sewage into the near-shore marine environment. This study examined bacterial reproduction within the temporary sewage-holding tanks of Rothera Research Station (Adelaide Island,…1 January, 2003 by Kevin Hughes
A novel endolithic microbial habitat is described from a climatically extreme site at Two Step Cliffs, Alexander Island, Antarctic Peninsula (71°54′S, 68°13′W). Small endolithic colonies (Read more on A novel Antarctic microbial endolithic community within gypsum crusts
1 January, 2003 by Kevin Hughes, Kevin Newsham
We tested the effects of solar radiation, and UV-B in particular, on the growth of Antarctic terrestrial fungi. The growth responses to solar radiation of five fungi, Geomyces pannorum, Phoma…Read more on Solar UV-B radiation inhibits the growth of Antarctic terrestrial fungi
1 January, 2003
Silurian and lower Devonian sedimentary successions are uncommon within the remnants of Gondwana. The Port Stephens Formation, the basal unit of the middle Palaeozoic West Falkland Group, presents a rare…1 January, 2003
The fish fauna of the continental shelf of the Southern Ocean is dominated by a single sub-order of Perciformes, the Notothenioidei, which have unusually large diameter skeletal muscle fibres. We…1 January, 2003
Allozyme variability was examined using starch-gel electrophoresis between sub-populations of Idotea chelipes over a small geographic distance (approx. 104 km), in lagoons within the Solent area (Fort Gilkicker Moat; Ashlett…1 January, 2003 by Anna Jones, Eric Wolff
The summertime atmospheric boundary layer over the South Pole has recently been shown to be highly oxidizing, with greater concentrations of NO and OH than previously expected. The source of…1 January, 2003 by Martin Collins
A series of baited camera and trap experiments in the eastern Mediterranean Sea between 1500 and 4264 m depth attracted a variety of opportunistic scavengers, with species composition changing with…1 January, 2003 by Kevin Newsham
We molecularly assessed the ascomycetous fungal communities inhabiting the rhizoid environment of Cephaloziella varians, collected at Rothera Point on the western Antarctic Peninsula. The RFLP-phenotyped and cloned PCR products of…1 January, 2003 by Adrian Jenkins
Large rifts that open in Antarctic ice shelves are known to be filled by snow accumulations, ice shelf fragments, and sea ice. This work demonstrates how these rifts may also…Read more on A model of marine ice formation within Antarctic ice shelf rifts
1 January, 2003 by John King
Surface pressure measurements from instruments deployed on ice floes in the southern Bellingshausen Sea were used to assess the accuracy of European Centre for Medium-Range Weather Forecasts (ECMWF) analyses in…Read more on Validation of ECMWF sea level pressure analyses over the Bellingshausen Sea, Antarctica
1 January, 2003 by Gareth Marshall, John King, John Turner, Thomas Lachlan-Cope
Climate observations made since the mid twentieth century reveal that the Antarctic Peninsula is a region of extreme climate variability and change. The pattern of change is, however, both seasonally…1 January, 2003 by John King
The west coast of the Antarctic Peninsula is a region of extreme interannual variability in near-surface temperatures. Recently the region has also experienced more rapid warming than any other part…Read more on The spatial coherence of interannual temperature variations in the Antarctic Peninsula
1 January, 2003
Mackerel icefish have a widespread distribution in the Atlantic and Indian Ocean sectors of the low-Antarctic region. Biological characteristics differ considerably between populations in the southern Scotia Arc and those…Read more on Shedding new light on the life cycle of mackerel icefish in the Southern Ocean
1 January, 2003
[1] Between 1996 and 1998, a concerted effort was made to study the deep open ocean convection in the Labrador Sea. Both in situ observations and numerical models were employed…Read more on The Labrador Sea Deep Convection Experiment data collection
1 January, 2003 by Mai Mai Lam
We test the proposal that the Sun’s magnetic activity, communicated via the solar wind, provides a link between solar variability and the Earth’s climate in the Antarctic troposphere. The strength…1 January, 2003
Planetary wave activity at quasi 16-, 10- and 5-day periods has been compared at various altitudes through the middle and upper atmosphere over Halley (76degreesS, 27degreesW), Antarctica, during the austral…Read more on Simultaneous observations of planetary waves from 30 to 220 km