Found 14065 items
1 January, 2008 by Hua Lu, Mark Clilverd
This study investigates if the descent of odd nitrogen, generated in the thermosphere and the upper mesosphere by energetic particle precipitation (EPP-NOx), has a detectable impact on stratospheric wind and…Read more on Geomagnetic perturbations on stratospheric circulation in late winter and spring
1 January, 2008 by Hua Lu
Statistically measurable responses of atmospheric circulation to solar wind dynamic pressure are found in the Northern Hemisphere (NH) zonal-mean zonal wind and temperature, and on the Northern Annular Mode (NAM)…1 January, 2008 by Gareth Marshall
The frequency of mesoscale cyclones in the Western Antarctic Peninsula (WAP) region during 1991-94 is correlated with the Southern Hemisphere Annular Mode (SAM) index, most strongly during winter and spring.…1 January, 2008
When planning the acquisition of new palaeo proxy data for reconstructing past climates, many factors influence the decision of where the proxies are to be collected. One such influence is…1 January, 2008
It is thought that the Northern Hemisphere experienced only ephemeral glaciations from the Late Eocene to the Early Pliocene epochs (about 38 to 4 million years ago), and that the…Read more on Late Pliocene Greenland glaciation controlled by a decline in atmospheric CO2 levels
1 January, 2008
Sunshade geoengineering - the installation of reflective mirrors between the Earth and the Sun to reduce incoming solar radiation, has been proposed as a mitigative measure to counteract anthropogenic global…1 January, 2008
The "Panama Hypothesis" states that the gradual closure of the Panama Seaway, between 13 million years ago (13 Ma) and 2.6 Ma, led to decreased mixing of Atlantic and Pacific…1 January, 2008
Systematic strategies from applied mathematics for stochastic modelling in climate are reviewed here. One of the topics discussed is the stochastic modelling of mid-latitude low-frequency variability through a few teleconnection…Read more on An applied mathematics perspective on stochastic modelling for climate
1 January, 2008
Passive microwave snow depth, ice concentration, and ice motion estimates are combined with snowfall from the European Centre for Medium-Range Weather Forecasting (ECMWF) reanalysis (ERA-40) from 1979-2001 to estimate the…1 January, 2008
Oceanic phytoplankton, absorbing solar radiation, can influence the bio-optical properties of seawater and hence upper ocean physics. We include this process in a global ocean general circulation model (OGCM) coupled…Read more on Ocean biogeochemical response to phytoplankton-light feedback in a global model
1 January, 2008
In September-October 2005, the juxtaposition of low-and high-pressure anomalies at 130 degrees W and 60 degrees W, respectively, created strong and persistent northerly airflow across the West Antarctic Peninsula (WAP).…1 January, 2008 by Andrew Clarke, John King, Michael Meredith
We investigate the seasonal variability in freshwater inputs to the Marguerite Bay region (Western Antarctic Peninsula) using a time series of oxygen isotopes in seawater from samples collected in the…1 January, 2008 by Eugene Murphy, John King, Michael Meredith
The ocean around South Georgia, in the southwest Atlantic sector of the Southern Ocean, is highly productive, with large stocks of Antarctic krill supporting extensive colonies of marine and land-based…1 January, 2008 by Michael Meredith
The Southern Ocean hosts the formation of the densest layers of the oceanic overturning circulation, and provides a climatically sensitive element of deep ocean ventilation. An oceanographic section across the…1 January, 2008 by Nigel Meredith, Richard Horne
Fast magnetosonic waves can lead to the local acceleration of electrons from ∼10 keV up to a few MeV on a timescale of 1–2 d and may play an important…1 January, 2008 by Gareth Marshall
The Antarctic Peninsula has displayed significant climate change over recent decades. Understanding contemporaneous changes in accumulation is made difficult because the region's complex orography means that ice-core data are not…1 January, 2008 by Tracy Moffat-Griffin
Gravity waves play an important role in determining the structure and dynamics of the mesopause region. In this study the Imaging Riometer for Ionospheric Studies (IRIS) at Halley, Antarctica (76S,…Read more on Observing mesospheric gravity waves with an imaging riometer.
1 January, 2008 by Andy Smith, Hugh Corr
[1] Spatially coincident radar and seismic data collected two weeks apart on Rutford Ice Stream were analyzed to investigate the mechanical and hydrological characteristics of the ice-bed interface. Seismic data…1 January, 2008
An unusually dense collection of some 150 dead crabeater seals (Family Phocidae), in various stages of decay, occurs in the Brandy Bay hinterland, north-western James Ross Island, northern Antarctic Peninsula.…1 January, 2008 by Keith Nicholls
During the austral winter of 2007 a Weddell Seal tagged with a miniaturized conductivity-temperature-depth (CTD) instrument travelled over the central southern Weddell Sea continental shelf. The instrument yielded 750 CTD…Read more on Wintertime ocean conditions over the southern Weddell Sea continental shelf, Antarctica
1 January, 2008 by Povl Abrahamsen, Keith Nicholls
A combination of measurements from Autosub, an autonomous underwater vehicle, and ship-based instruments are used to describe the oceanographic conditions beneath Fimbul Ice Shelf, Antarctica. The data show an intricate…Read more on High-latitude oceanography using the Autosub autonomous underwater vehicle
1 January, 2008 by Gareth Marshall, John Turner
Although both the Arctic and Antarctic are subject to a similar annual cycle of solar radiation and the same increasing greenhouse gas concentrations, over the previous two decades the two…Read more on The Arctic and Antarctic: two faces of climate change
1 January, 2008
With global land and sea temperatures rising, the importance of accurate monitoring of the world's ice sheets is increasing. Satellite radar altimetry can be used to measure elevation changes of…Read more on Greenland: Bringing together remote sensing and fieldwork.
1 January, 2008
Compilation of existing population data through the 1999/2000 season for Northern Giant Petrels Macronectes halli and Southern Giant Petrels M. giganteus indicates that the total breeding population of Northern Giant…1 January, 2008 by David Pearce
Seven independent clone libraries were constructed to study the biodiversity of the bacterioplankton in the surface waters around Southern Thule, South Sandwich Islands, in order to identify the species present,…1 January, 2008 by Lloyd Peck
Animals can respond in three main ways to environments that change and deteriorate. They can cope with their inherent physiological flexibility, evolve or adapt to new conditions, or migrate away…1 January, 2008 by Lloyd Peck, Melody Clark
Cold-blooded Antarctic marine species are highly stenothermal and possibly the most temperature-sensitive group on Earth. Studies to date have produced upper lethal temperatures in the range of 4 to 10…1 January, 2008 by Mervyn Freeman
Collisionless magnetic reconnection requires the violation of ideal MHD by various kinetic-scale effects. Recent research has highlighted the potential importance of wave-particle interactions by showing that Vlasov simulations of unstable…Read more on Nonlinear dependence of ion-acoustic anomalous resistivity on electron drift velocity
1 January, 2008
Release of stored magnetic energy via particle acceleration is a characteristic feature of astrophysical plasmas. Magnetic reconnection is one of the primary candidate mechanisms for releasing non-potential energy from magnetized…Read more on Fluctuating electric field particle acceleration at a magnetic field null point
1 January, 2008 by Janet Silk, Richard Phillips
1. A wide range of instrumentation has been deployed on albatrosses and petrels at Bird Island, South Georgia, in studies dating back to the mid-1980s. Early results indicated the huge…1 January, 2008 by Claire Allen
During the past ten years, the Antarctic Peninsula has been identified as the most rapidly warming region of the Southern Hemisphere and it is important to place this warming in…1 January, 2008
The hydrothermal vent zoarcid fish Thermarces cerberus is a top predator that inhabits deep-sea hydrothermal vents on the East Pacific Rise (EPR). Bacterial chemoautotrophy at these sites supports abundant animal…1 January, 2008 by Peter Convey
Aim. To identify Antarctic palaeoendemic taxa and their probable glacial refugia from regional groups of endemic species records. Location. Antarctica. Methods. We compiled a list of Antarctic non-marine invertebrates from…Read more on Surviving out in the cold: Antarctic endemic invertebrates and their refugia
1 January, 2008 by Michael Thorne, Roger Worland, Melody Clark
The physiology of the Antarctic microarthropod, Cryptopygus antarcticus, has been well studied, particularly with regard to its ability to withstand low winter temperatures. However, the molecular mechanisms underlying this phenomenon…1 January, 2008 by Richard Phillips
This study examined divergence in the foraging distribution, at-sea behaviour and provisioning strategies of a small procellarid, the Cook’s petrel Pterodroma cookii, during chick-rearing at 2 islands off New Zealand,…1 January, 2008
Carbon dioxide (CO2) is a kinetically and thermodynamically stable molecule. It is easily formed by the oxidation of organic molecules, during combustion or respiration, but is difficult to reduce. The…Read more on Reversible interconversion of carbon dioxide and formate by an electroactive enzyme
1 January, 2008 by Eugene Murphy
1. Implementing an ecosystem approach to fisheries management requires an effective ecosystem monitoring programme, the utility of which depends upon its ability (measured by the statistical power) to detect effects…1 January, 2008 by Howard Roscoe
The UV-visible Global Ozone Monitoring by Occultation of Stars (GOMOS) instrument onboard Envisat performs nighttime measurements of ozone, NO2, NO3 and of the aerosol extinction, using the stellar occultation method.…1 January, 2008 by Richard Phillips
Whilst we have now a good understanding how past glaciation influenced species at the northern hemisphere, our knowledge of patterns and modes of speciation is far more limited for the…1 January, 2008 by Dominic Hodgson, James Smith, Stephen Roberts
The Antarctic Peninsula has experienced a dramatic increase in temperature and the loss of ca. 14,000 km2 of ice-shelf area in recent years. During this time George VI Ice Shelf…1 January, 2008 by Mark Clilverd
For some time theoretical modeling has shown that electromagnetic ion cyclotron (EMIC) waves should play an important role in the loss of relativistic electrons from the radiation belts, through precipitation…1 January, 2008 by Mark Clilverd
For many years it has been suggested that transient luminous events (TLE) occurring over thunderstorms may produce significant modifications to neutral atmospheric chemistry. Some have speculated that large ionisation increases…1 January, 2008 by Mark Clilverd
The Carrington event of August/September 1859 was the most significant solar proton event (SPE) of the last 450 years, about four times larger than the solar proton fluence of the…Read more on Atmospheric impact of the Carrington event solar protons
1 January, 2008 by Paul Rodhouse
Over the last four decades, several ommastrephid squid stocks have shown rapid expansion and contraction, driving highly variable and sometimes boom and bust fisheries. These include Illex illecebrosus in the…1 January, 2008 by Alexandra Weiss
The Mesoscale Alpine Programme's Riviera project investigated the turbulence structure and related exchange processes in an Alpine valley by combining a detailed experimental campaign with high-resolution numerical modelling. The present…1 January, 2008 by Eric Wolff
To improve quantitative interpretation of ice core aeolian dust records, a systematic methodological comparison was made. This involved methods for water-insoluble particle counting (Coulter counter and laser-sensing particle detector), soluble…Read more on Proxies and measurement techniques for mineral dust in Antarctic ice cores
1 January, 2008
Aim To produce a robust, comprehensive global biome reconstruction for the Middle Pliocene (c. 3.6–2.6 Ma), which is based on an internally consistent palaeobotanical data set and a state-of-the-art coupled…Read more on A new global biome reconstruction and data-model comparison for the Middle Pliocene
1 January, 2008 by Chester Sands, Katrin Linse, Peter Convey, Sandra McInnes, Sandra McInnes, Will Goodall-Copestake
Phylum Tardigrada consists of similar to 1000 tiny, hardy metazoan species distributed throughout terrestrial, limno-terrestrial and oceanic habitats. Their phylogenetic status has been debated, with current evidence placing them in…1 January, 2008 by Dominic Hodgson
Since European settlement began over 200 years ago, many southeast Australian coastal lakes and lagoons have experienced substantial human impacts, including nutrient enrichment. Present day management and conservation efforts are…1 January, 2008 by Huw Griffiths
The Antarctic gastropod Dickdellia labioflecta (Dell, 1990) (originally described as Laevilittorina (Corneolittorina) labioflecta) is an obligate parasite of pycnogonids, which exploits their body fluids through the cuticular gland holes (Lehmann…1 January, 2008
Studies of post-mortem interval on the stability of RNA from a number of various mammals have shown RNA to be stable for between 24 and 48 h following death. As…Read more on Stability of RNA isolated from post-mortem tissues of Atlantic salmon (Salmo salar L.)
1 January, 2008 by Mark Clilverd
The stratospheric and mesospheric impacts of the solar proton events of January 2005 are studied here using ion and neutral chemistry modeling and subionospheric radio wave propagation observations and modeling.…Read more on The effects of hard-spectra solar proton events on the middle atmosphere
1 January, 2008 by Nigel Meredith
In this paper, we focus on the modeling of radial transport in the Earth's outer radiation belt. A historical overview of the first observations of the radiation belts is presented,…1 January, 2008 by Nigel Meredith
This paper focuses on the modeling of local acceleration and loss processes in the outer radiation belt. We begin by reviewing the statistical properties of waves that violate the first…1 January, 2008 by Eric Wolff, Louise Sime
Results from an isotope-enabled general circulation model are presented in order to determine the isotopic signal of a warmer climate on Antarctica. The warming is forced using CO2 forecasts for…Read more on Antarctic isotopic thermometer during a CO2 forced warming event
1 January, 2008
Many shallow water polar communities demonstrate considerable change along a bathymetric gradient. However, it is currently unclear whether community change is generally continuous or discrete. To determine the nature of…1 January, 2008
Benthic communities in nearshore habitats around Antarctica are strongly influenced by ice disturbance. It has been suggested that where ice scour disturbance is severe, the relative importance of certain ecological…1 January, 2008
Studies from temperate and tropical regions have shown that variability in the distribution of benthos exists at different spatial scales. There are very few similar studies from polar systems, the…1 January, 2008 by David Barnes
Disturbance has always shaped the evolution and ecology of organisms and nowhere is this more apparent that on the iceberg gouged continental shelves of the Antarctic Peninsula (AP). The vast…1 January, 2008 by David Barnes, Lloyd Peck
Disturbance is a key structuring force influencing shallow water communities at all latitudes. Polar nearshore communities are intensely disturbed by ice, yet little is known about benthic recovery following iceberg…1 January, 2008
Subglacially-erupted volcanic sequences provide proxies for a unique range of palaeo-ice parameters and they are potentially highly useful archives of palaeoenvironmental information, particularly for pre-Quaternary periods. They can thus be…1 January, 2008 by Joanne Johnson
Basaltic volcanism in the James Ross Island region has been persistent over the last 6 million years resulting in at least 50 mainly effusive eruptions that are preserved predominantly as…1 January, 2008 by Iain Staniland
Antarctic fur seals show extreme sexual size dimorphism and their breeding strategies place very different constraints on the behaviour of males and females. Whereas the foraging behaviour of lactating females…1 January, 2008
The last two abrupt warmings at the onset of our present warm interglacial period, interrupted by the Younger Dryas cooling event, were investigated at high temporal resolution from the North…1 January, 2008
The Mariana Arc of submarine volcanoes has recently been the site of an international, interdisciplinary study into the structure and function of the associated hydrothermal systems. A broad size range…1 January, 2008
Astrammina rara, Crithionina delacai, and Notodendrodes hyalinosphaira are 3 of the largest and most abundant members of the foraminiferal assemblage at a shallow-water (28 to 32 m) site in Explorers…1 January, 2008 by Nigel Meredith, Richard Horne
Nonadiabatic loss processes of radiation belt energetic electrons include precipitation loss to the atmosphere due to pitch-angle scattering by various magnetospheric plasma wave modes. Here we consider electron precipitation loss…Read more on Electron scattering by whistler-mode ELF hiss in plasmaspheric plumes
1 January, 2008
The Greenland Ice Core Chronology 2005 (GICC05) is a time scale based on annual layer counting of high-resolution records from Greenland ice cores. Whereas the Holocene part of the time…Read more on A 60 000 year Greenland stratigraphic ice core chronology
1 January, 2008 by Philip Trathan, Vsevolod Afanasyev
We used miniature light-level/immersion loggers (geolocators) to study the movements and behavior of two Streaked Shearwaters (Calonectris leucomelas) during their travel away from Japan, after the breeding season. During the…1 January, 2008 by Geraint Tarling
Levels of infestation by the suctorian Ephelota sp. were determined in Antarctic krill taken in the north-eastern region of the Scotia sea, close to the island of South Georgia. Individuals…1 January, 2008 by Claus-Dieter Hillenbrand, Robert Larter
Today, Antarctica exhibits some of the harshest environmental conditions for life on Earth. During the last glacial period, Antarctic terrestrial and marine life was challenged by even more extreme environmental…Read more on Life hung by a thread: endurance of Antarctic fauna in glacial periods
1 January, 2008 by Peter Convey
1 January, 2008 by Gareth Marshall, Liz Thomas
We present results from a new medium depth (136 metres) ice core drilled in a high accumulation site (73.59S,70.36W) on the south-western Antarctic Peninsula during 2007. The Gomez record reveals…Read more on A doubling in snow accumulation in the western Antarctic Peninsula since 1850
1 January, 2008 by Eric Wolff, Liz Thomas, Robert Mulvaney
A new sub-seasonal chemical record is presented from the North Greenland Icecore Project (NorthGRIP) ice core during the onset of one of the longest and strongest interstadials of the last…Read more on A change in seasonality in Greenland during a Dansgaard–Oeschger warming
1 January, 2008 by Andrew Fleming, Martin Collins, Philip Trathan
Marine predators are thought to follow sophisticated scale-dependent search strategies when seeking patchy and unpredictable prey. However, fine-scale information about these strategies has hitherto been difficult to obtain for diving…Read more on Linear tracks and restricted temperature ranges characterise penguin foraging pathways
1 January, 2008 by Jaume Forcada, Philip Trathan
Goudier Island is located in the Palmer Archipelago, to the west of the Antarctic Peninsula; it is one of the most frequently visited tourist sites in Antarctica. A number of…1 January, 2008 by Jonathan Shanklin
The 2007 Antarctic ozone hole is reviewed from a variety of perspectives, making use of various Australian data and analyses. The 2007 ozone hole was relatively modest, particularly in comparison…1 January, 2008 by Kevin Newsham
The two native Antarctic vascular plant species, Colobanthus quitensis and Deschampsia antarctica, were sampled from 15 points along a 1480 km latitudinal transect from South Georgia (54°S, 36°W) through to…1 January, 2008 by Andrew Orr, Gareth Marshall, John King
The large regional summer warming on the east coast of the northern Antarctic Peninsula (AP), which has taken place since the mid-1960s, has previously been proposed to be caused by…1 January, 2008
El Nino Southern Oscillation events have been associated with large fluctuations in seabird and landbird populations of the Galapagos Islands. We reveal different effects of climatic variation on the abundance…1 January, 2008 by Nigel Meredith, Richard Horne, Sarah Glauert
We present results from our three-dimensional (3-D) simulations using the Salammbô electron radiation belt physical model. We have run steady state and dynamic storm test case simulations to study the…1 January, 2008
The oceanic southern margin of Gondwana, from southern South America through South Africa, West Antarctica, New Zealand (in its pre break-up position), and Victoria Land to Eastern Australia is one…1 January, 2008 by David Vaughan
It is now almost 30 years since John Mercer (1978) first presented the idea that climate change could eventually cause a rapid deglaciation, or “collapse”, of a large part of…Read more on West Antarctic Ice Sheet collapse – the fall and rise of a paradigm
1 January, 2008 by Andy Smith, David Vaughan, Hugh Corr, Hamish Pritchard
Rutford Ice Stream and Carlson Inlet are neighbouring glaciers in West Antarctica. Rutford Ice Stream flows at speeds greater than 350m a(-1), whereas Carlson Inlet, which has some similar dimensions…