Showing 13455 items
1 January, 2002 by Dominic Hodgson
The authenticity of hydroxychlorophyllderivatives in sediments has been verified by subjecting pure chlorophyll preparations to the extraction method used for sediments. Model studies of chlorophyll autoxidation reveal hydroxychlorophyll as the…Read more on Origin and significance of 13(2)-hydroxychlorophyll derivatives in sediments
1 January, 2002 by Peter Convey
There is now ample evidence of the ecological impacts of recent climate change, from polar terrestrial to tropical marine environments. The responses of both flora and fauna span an array…1 January, 2002 by Eugene Murphy, Jonathan Watkins, Michael Meredith, Peter Ward, Sally Thorpe
The coupling of physics and biology was examined along a 160 km long transect running out from the north coast of South Georgia Island and crossing the Southern Antarctic Circumpolar…1 January, 2002 by Jonathan Watkins
Acoustic surveys to estimate krill biomass require that the sound backscattered by krill can be identified and distinguished from all other types of backscatter. Sampling acoustic targets with nets to…Read more on Verification of the acoustic techniques used to identify Antarctic krill
1 January, 2002
The study of the robust features of the magnetosphere is motivated both by new “whole system” approaches, and by the idea of “space climate” as opposed to “space weather”. We…1 January, 2002 by Mervyn Freeman, Richard Horne
Analytical estimates of resistivity due to electrostatic current-driven ion-acoustic waves are compared with Vlasov simulation results. Particular attention is given to the case of similar ion and electron temperatures that…Read more on Ion-acoustic resistivity in plasmas with similar ion and electron temperatures
1 January, 2002 by Anna Jones
NO, NOy (total reactive nitrogen oxides), gaseous HNO3, and particulate nitrate (p-NO3−) were measured at Neumayer Station from February 1999 to January 2000. In addition, during February 1999, the NOy…Read more on Seasonality of reactive nitrogen oxides (NOy) at Neumayer Station, Antarctica
1 January, 2002
Hydrothermal alteration in volcanic arcs occurs in many settings and may involve magmatic, marine, lacustrine or groundwaters, driven by magmatic, tectonic or thermal events. King George Island, part of the…1 January, 2002
An expanded Oligocene-Miocene boundary interval recovered in the Cape Roberts Project CRP-2A core from beneath the Ross Sea, Antarctica, has yielded a high-resolution integrated chrono stratigraphy that has, in turn,…1 January, 2002
The routine use of spectrophotometry on the sediment surfaces of archive halves of each section during the onboard sedimentological core description process is a great stride toward development of real-time…1 January, 2002 by Claus-Dieter Hillenbrand
The area west of the Antarctic Peninsula is a key region for studying and understanding the history of glaciation in the southern high latitudes during the Neogene with respect to…1 January, 2002 by Andrew Clarke, Peter Ward
Diversity and structure of copepod assemblages were investigated using 259 WP2 zooplankton samples collected from the top 200 m of the Atlantic Ocean between 60°N and 63°S. Whilst richness at…1 January, 2002
This paper describes a unique record of glacier flow instability for East Greenland during the Little Ice Age. Trace metal analysis of sediment cores collected during 1998 from the Noret…1 January, 2002
Solar radiation is the primary energy source for surface planetary life, so that pigments are fundamental components of any surface-dwelling organism. They may therefore have evolved in some form on…1 January, 2002
The launch of a new journal is appropriately like a space mission. It is the result of a scientific need, the inspiration of a group of committed scientists and technologists,…Read more on Editorial: The International Journal of Astrobiology
1 January, 2002 by Paul Rodhouse
The cephalopod component of the diet of Patagonian toothfish, Dissostichus eleginoides, around South Georgia was analysed from stomach contents collected between March and May 2000. Cephalopods occurred in 7% of…1 January, 2002 by Paul Rodhouse
In Southwest Atlantic waters, the short-finned squid Illex argentinus is distributed along the Patagonian shelf and slope, from approximately 22° to 54°S ( Haimovici et al., 1998). I. argentinus has…1 January, 2002
Latitudinal and diurnal distributions of spectral power and spatial coherency parameters of the geomagnetic variations in the Pc5-6 (1–6 mHz) frequency range are analyzed using data of magnetometer stations in…1 January, 2002 by Martin Collins
The scavenging megafauna of the South Georgia and Shag Rocks slope in the south-west Atlantic (625-15 19 m) were investigated using autonomous baited camera systems. Two surveys were conducted: the…Read more on Scavenging by megabenthos and demersal fish on the South Georgia slope
1 January, 2002 by John King
Practically oriented flux-calculation techniques based on correction functions to the neutral drag and heat/mass transfer coefficients are further developed. In the traditional formulation, the correction functions depend only on the…1 January, 2002 by Robert Mulvaney
A medium-length ice core was drilled at the ice divide on the Lomonosovfonna plateau (1230 m a.s.l.),Svalbard, in May1997.As part of this project, temperature measurements were performed in the 120…1 January, 2002
Geophysical data from the Antarctic Peninsula continental shelf reveal streamlined subglacial bedforms in a cross-shelf trough. Bedforms exhibit progressive elongation with distance along the trough, and record flow of a…1 January, 2002
Geological evidence indicates that sediment reworking is common around the continental margins and abyssal depths of the Norwegian-Greenland Sea, a high-latitude setting with glacier-influenced margins. Detailed analysis of 22 cores…1 January, 2002
Operation Chastise, more often known as the ‘Dambusters raids’, was one of the most audacious aerial military operations of the Second World War, in that it made use of operationally…Read more on The science and scientific legacy of Operation Chastise
1 December, 2001
Unlike previous missions to the magnetotail (IMP 6, ISEE 1, ISEE 3, and Geotail), which effectively made observations in the lobe at a single downtail distance, the Cassini Earth swingby…1 December, 2001 by Mark Clilverd
It has been suggested that quasi-electrostatic electric fields from thunderclouds might produce whistler ducts by driving plasma interchange of geomagnetic flux tubes. Using lightning activity as a proxy for the…Read more on Investigating the possible association between thunderclouds and plasmaspheric ducts
1 December, 2001 by Gareth Chisham, Mervyn Freeman, Michael Pinnock
This paper sets out a critical test of the antiparallel merging hypothesis. For the conflicting theories of antiparallel and subsolar reconnection, we model the location of reconnection regions on the…Read more on An ionospheric convection signature of antiparallel reconnection
1 December, 2001 by Mervyn Freeman
Auroral spirals are the largest vortex structures that appear in auroral arcs. Their diameters vary from tens to hundreds of kilometers. We have collected an all-sky camera data set of…1 December, 2001
On August 18, 1999, Cassini flew by the Earth on its way to Saturn. The Cassini Earth swing-by was the fastest traversal of the Earth's magnetosphere to date. The spacecraft…1 October, 2001 by Richard Hindmarsh, Richard Hindmarsh
Ice‐sheet flows can be channelled by perturbations in the basal topography or in the sliding coefficient. These lead to spatial variation in the steady profile, the flux and the dissipative…Read more on Influence of channelling on heating in ice-sheet flows
15 September, 2001 by Keith Nicholls
This is the first large-scale modeling study of iceberg trajectories and melt rates in the Southern Ocean. An iceberg model was seeded with climatological iceberg calving rates based on a…Read more on Iceberg trajectory modeling and meltwater injection in the Southern Ocean
1 September, 2001 by Robert Mulvaney
The atmospheric trend of methane isotopic ratios since the mid-20th century has been reconstructed from Antarctic firn air. High volume air samples were extracted at several depth levels at two…1 July, 2001 by Mai Mai Lam
This paper tests the Araki [1994] computational model of the Earth-ionosphere system during geomagnetic sudden commencement (sc). In particular, we test the model's ability to predict the signs of the…Read more on A case study test of Araki’s physical model of geomagnetic sudden commencement
1 July, 2001 by Richard Horne
Intense interest currently exists in determining the roles played by various wave-particle interactions in the acceleration of electrons to relativistic energies during/following geomagnetic storms. Here we present a survey of…15 June, 2001 by Keith Makinson, Keith Nicholls
We have made oceanographic measurements at two sites beneath the southern Filchner-Ronne Ice Shelf. Hot-water drilled access holes were made during January 1999, allowing conductivity-temperature-depth (CTD) profiling and the deployment…10 June, 2001 by Adrian Jenkins, Andy Smith, David Vaughan, Hugh Corr, Richard Hindmarsh, Richard Hindmarsh
Measurements of ice thickness on the Antarctic ice sheet collected during surveys undertaken over the past 50 years have been brought together into a single database. From these data, a…Read more on BEDMAP: A new ice thickness and subglacial topographic model of Antarctica
1 June, 2001 by Peter Kirsch
Results from an intercomparison campaign of ultraviolet spectroradiometers that was organized at Nea Michaniona, Greece July, 1–13 1997, are presented. Nineteen instrument systems from 15 different countries took part and…Read more on SUSPEN intercomparison of ultraviolet spectroradiometers
1 June, 2001 by Adrian Jenkins, Richard Hindmarsh, Richard Hindmarsh
We use an ice‐sheet model to show that (i) margins of marine ice‐sheets can be expected to be frozen to the bed, except where ice‐streams discharge; (ii) 20–50km retreats induced…Read more on Centurial‐millenial ice‐rafted debris pulses from ablating marine ice sheets
27 May, 2001 by John Turner, Thomas Lachlan-Cope
In polar regions, satellite microwave radiometry has not been successful in measuring the total water vapor (TWV) in the atmosphere. The difficulties faced in these regions arise from the very…1 April, 2001 by Anna Jones, Eric Wolff
It has been shown that NOx is produced photochemically within the snowpack of polar regions. If emitted to the atmosphere, this process could be a major source of NOx in…Read more on Measurements of NOx emissions from the Antarctic snowpack
1 April, 2001 by Michael Meredith
Two hydrographic and δ18O transects across Fram Strait (Aug–Sept 1997, 1998) are used to examine freshwater contributions to the East Greenland Current (EGC). The EGC featured up to ∼16% meteoric…Read more on Freshwater fluxes through the western Fram Strait
1 March, 2001
We report simultaneous measurements of the O2(¹Δ) and O2(¹Σ) airglow volume emission rate profiles in the daytime mesosphere. We use these measurements to derive ozone concentrations separately from each airglow.…1 February, 2001 by Anna Jones, Howard Roscoe
Calculations of equivalent length from an artificial advected tracer provide new insight into the isentropic transport processes occurring within the Antarctic stratospheric vortex. These calculations show two distinct regions of…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…