Found 14089 items
1 January, 2012 by Geraint Tarling
The population dynamics, individual growth rates and productivity of the hyperiid amphipod Themisto gaudichaudii were studied in Cumberland Bay, a fjord on the north-eastern coast of South Georgia. The study…1 January, 2012 by Robert Larter
Multichannel seismic reflection lines collected in the western Amundsen Sea Embayment (ASE) provide an insight into the sedimentary cover on the shelf, which documents glacial processes. Numerous columnar, reflection-poor structures…1 January, 2012 by Hugh Venables
The Scotia Sea area has high productivity relative to the Southern Ocean as a whole, but this displays strong latitudinal and longitudinal gradients. Elucidating the extent of these from a…1 January, 2012 by Alistair Crame, Katrin Linse, Rowan Whittle
Nuculid bivalves of the Cape Melville Formation (Early Miocene, King George Island) are reviewed. Ten bivalve taxa are listed from the formation in the families Nuculidae (two species), Sareptidae, Malletiidae,…1 January, 2012 by Rosie Williams, Robert Arthern, Richard Hindmarsh, Richard Hindmarsh
Changes at the grounding line of ice streams have consequences for inland ice dynamics and hence sea level. Despite substantial evidence documenting upstream propagation of frontal change, the mechanisms by…1 January, 2012 by Robert Larter
We present a reconstruction of the Antarctic topography at the Eocene–Oligocene (ca. 34 Ma) climate transition. This provides a realistic key boundary condition for modeling the first big Antarctic ice…Read more on Antarctic topography at the Eocene-Oligocene boundary
1 January, 2012 by Emilie Capron
Insoluble trace gases are trapped in polar ice at the firn-ice transition, at approximately 50 to 100 m below the surface, depending primarily on the site temperature and snow accumulation.…1 January, 2012 by Eric Wolff, Markus Frey
The Carrington Event of 1859 is considered to be among the largest space weather events of the last 150 years. We show that only one out of 14 well-resolved ice…Read more on The Carrington event not observed in most ice core nitrate records
1 January, 2012 by Eric Wolff
Chemical and isotopic records obtained from polar ice cores have provided some of the most iconic datasets in Earth system science. Here, I discuss how the different records are formed…Read more on Chemical signals of past climate and environment from polar ice cores and firn air
1 January, 2012 by Simeon Hill
This study provides the first description of the feeding ecology of the smooth lanternshark Etmopterus pusillus based on stomach contents of specimens caught as bycatch in the Algarve (southern Portugal)…1 January, 2012 by Povl Abrahamsen
In search of an explanation for some of the greenest waters ever seen in coastal Antarctica and their possible link to some of the fastest melting glaciers and declining summer…Read more on The Amundsen Sea Polynya International Research Expedition (ASPIRE)
1 January, 2012 by Philip Trathan
Foraging trip duratiom of breeding seabirds is affected by characteristics of available feeding habitat in the marine environment, which may in turn, generate inter-colony difference in the patterns of nest…1 January, 2012 by Eugene Murphy, Emma Young, Mark Belchier, Michael Meredith
Waters around South Georgia are amongst the most productive in the Southern Ocean, and support internationally important fisheries. However, there is significant inter-annual variability in fish stocks, and some species…1 January, 2012 by Peter Convey
Despite a widespread recognition of the role of seabird colonies in the fertilization of nutrient-poor polar terrestrial ecosystems, qualitative and quantitative data documenting any consequential influence on soil invertebrate communities…1 January, 2012
The tracking of small avian migrants has only recently become possible by the use of small light-level geolocators, allowing the reconstruction of whole migration routes, as well as timing and…1 January, 2012 by Dominic Hodgson
The Antarctic continent, including its ice shelves, has an area of 13.8 million km2, about half the size of North America and 1.3 times the size of Europe. It is…7 December, 2011
A mesospheric front was observed with an allsky airglow imager on the night of 9–10 July 2007 at Ferraz Station (62 degrees S, 58 degrees W), located on King George…2 December, 2011 by Jean-Baptiste Sallee, Michael Meredith
Drake Passage is the narrowest constriction of the Antarctic Circumpolar Current (ACC) in the Southern Ocean, with implications for global ocean circulation and climate. We review the long-term sustained monitoring…1 December, 2011 by Nigel Meredith, Richard Horne
We simulate the spatial and spectral distributions of plasmaspheric hiss using a technique that involves extensive ray tracing. The rays are injected in the equatorial chorus source region outside the…Read more on Modeling the wave power distribution and characterisitics of plamaspheric hiss
1 December, 2011 by Adrian Jenkins
Subglacial meltwater draining along the bed of fast-flowing, marine-terminating glaciers emerges at the grounding line, where the ice either goes afloat to form an ice shelf or terminates in a…16 November, 2011 by Ed King, Richard Hindmarsh, Richard Hindmarsh
Bedrock uplift in Antarctica is dominated by a combination of glacial isostatic adjustment (GIA) and elastic response to contemporary mass change. Here, we present spatially extensive GPS observations of Antarctic…4 November, 2011 by Mervyn Freeman
We present an analysis of ionospheric electric field data observed during a geomagnetic storm by the recently deployed HF radar located on the Falkland Islands. On 3 August 2010 at…4 November, 2011 by Mervyn Freeman
Meteor wind data from the first year of operation of the Falkland Islands SuperDARN radar (52° S, 59° W) are used to characterize the atmospheric tides and background winds in…1 November, 2011 by Mark Clilverd
Observed phases and amplitudes of VLF radio signals propagating on very long paths are used to validate electron density parameters for the lowest edge of the (D region of the)…Read more on Daytime D region parameters from long-path VLF phase and amplitude
1 November, 2011 by Angelika Renner, Sally Thorpe
We present observations of high-frequency current variability on the continental shelf and the slope of the Antarctic Peninsula using Lagrangian surface drifters deployed as part of the Antarctic Drifter Experiment:…27 October, 2011 by Ailsa Stroud, Liz Thomas, Louise Sime, Robert Mulvaney
Recent developments in ice melter systems and continuous flow analysis (CFA) techniques now allow higher-resolution ice core analysis. Here, we present a new method to aid interpretation of high-resolution ice…22 October, 2011 by Robert Mulvaney
The accumulation, isotopic and chemical signals of an ice core from James Ross Island, Antarctica, are investigated for the interval from 1967 to 2008. Over this interval, comparison with station,…Read more on Environmental signals in a highly resolved ice core from James Ross Island, Antarctica
21 October, 2011 by Ed King
The Antarctic Ice Sheet loses mass to the surrounding ocean mainly by drainage through a network of ice streams: fast-flowing glaciers bounded on either side by ice flowing one or…Read more on Ice stream or not? Radio-echo sounding of Carlson Inlet, West Antarctica
16 October, 2011
All-sky CCD observations of mesospheric gravity waves have been made from Halley Station Antarctica (75.5°S, 26.7°W) as part of a collaborative research program between British Antarctic Survey, U.K. and Utah…Read more on The evolution of a breaking mesospheric bore wave packet
16 October, 2011 by Alexandra Weiss, John King, Thomas Lachlan-Cope
We study the effective aerodynamic roughness length z0_eff and scalar roughness length for temperature zT_eff over different compact sea ice types in the Antarctic Weddell Sea by aircraft measurements during…Read more on On the effective aerodynamic and scalar roughness length of Weddell Sea ice
1 October, 2011 by Eric Wolff, Robert Mulvaney
Valuable information about the environment and climate of the past is preserved in ice cores which are drilled through ice sheets in polar and alpine regions. A pivotal part of…Read more on Bayesian Glaciological Modelling to quantify uncertainties in ice core chronologies
1 October, 2011 by Nigel Meredith, Richard Horne
Using the statistical CRRES measurements of the electric field intensities of lower band chorus (LBC) and upper band chorus (UBC) around L = 6 under geomagnetically moderate conditions, we evaluate…29 September, 2011 by Louise Sime
The sensitivity of interglacial Greenland temperature to orbital and CO2 forcing is investigated using the NorthGRIP ice core data and coupled ocean-atmosphere IPSL-CM4 model simulations. These simulations were conducted in…21 September, 2011 by Markus Frey
Measurements of e-folding depth, nadir reflectivity and stratigraphy of the snowpack around Concordia station (Dome C, 75.10 S, 123.31 E) were undertaken to determine wavelength dependent coefficients (350 nm to…16 September, 2011
We investigate enhancements of mesospheric nitric acid (HNO(3)) in the Northern Hemisphere polar night regions during the January 2005 and December 2006 solar proton events (SPEs). The enhancements are caused…12 September, 2011 by Robert Larter
Overall Objective: Review existing data and identify priorities for future geoscience research (terrestrial, marine and airborne) in the Amundsen Sea embayment (ASE) region required to develop a better understanding of…8 September, 2011 by Anna Jones, Eric Wolff
Measurements of a suite of individual NOy components were carried out at Halley station in coastal Antarctica as part of the CHABLIS campaign (Chemistry of the Antarctic Boundary Layer and…1 September, 2011 by Richard Horne
Electromagnetic ion cyclotron (EMIC) waves are an integral component of the Earth's dynamic space environment. In order to quantify their effect, it is necessary to know their saturation amplitude, but…Read more on Saturation characteristic of electromagnetic ion cyclotron waves
1 September, 2011
Both observations and high resolution numerical models show that the Southern Ocean circumpolar flow is concentrated in a large number (approximately 8 to 12) of narrow filamentary jets. It is…Read more on Low frequency variability of Southern Ocean jets
27 August, 2011 by Hua Lu, Mark Clilverd
The relationship between the geomagnetic aa index and the winter North Atlantic Oscillation (NAO) has previously been found to be nonstationary, being weakly negative during the early 20th century and…23 August, 2011 by Neil Brough
The Greenland Summit Halogen-HO(x) (GSHOX) Campaign was performed in spring 2007 and summer 2008 to investigate the impact of halogens on HO(x) (= OH+HO(2)) cycling above the Greenland Ice Sheet.…15 August, 2011
The stability of the Earth's major ice sheets is a critical uncertainty in predictions of future climate and sea level change. One method of investigating the behaviour of the Greenland…Read more on Sensitivity of Pliocene ice sheets to orbital forcing
2 August, 2011 by Michael Meredith
Results from the development and analysis of a novel temperature dataset for the high latitude North-West Atlantic are presented. The new 1 degrees gridded dataset ("ATLAS") has been produced from…1 August, 2011 by Richard Horne
Plasmaspheric hiss (PH) is a band-limited, incoherent whistler mode emission found predominantly in the plasmasphere or high-density plasma regions in the near-Earth space environment. Since its discovery in the late…Read more on Modeling the evolution of chorus waves into plasmaspheric hiss
1 August, 2011 by Paul Holland
The flow of dense polar shelf waters down continental slopes is a critical component of the global ocean circulation. Recent observations suggest that such plumes can be heavily impacted by…1 August, 2011 by Richard Horne
Radiation belt dynamics have been modeled by the modified Fokker-Planck diffusion equation with sources from the low-energy plasma sheet population and losses to the atmosphere and magnetopause. We perform a…1 August, 2011 by Michael Meredith, Zhaomin Wang
The Coupled Model Intercomparison Project phase 3 (Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report) models show a consistent intensification and poleward shift of the westerly winds over the…27 July, 2011 by Steve Colwell, Tracy Moffat-Griffin
An 8 year series of 965 high-resolution radiosonde soundings over Rothera (67 degrees S, 68 degrees W) on the Antarctic Peninsula are used to study gravity wave characteristics in the…18 July, 2011 by Hugh Corr, Richard Hindmarsh, Richard Hindmarsh
The boundary of grounded ice and the location of ice transitioning to a freely floating state are mapped at 15-m resolution around the entire continent of Antarctica. These data products…18 July, 2011 by Andy Smith
We present results from new geophysical data allowing modelling of the water flow within Subglacial Lake Ellsworth (SLE), West Antarctica. Our simulations indicate that this lake has a novel temperature…16 July, 2011 by Hua Lu, Ingrid Cnossen
We analyzed observational geopotential height data to provide some new insights on the 11 year solar cycle signal in the Northern Hemisphere early winter and its modulation by the quasi-biennial…11 July, 2011 by Chester Sands, David Herbert, David Barnes, Huw Griffiths, Martin Collins, Oliver Hogg, Peter Fretwell
The multilateral failure to apply the Convention on Biological Diversity (CBD) by the target year 2010 was headline news as are the accelerating climatic changes which dictate its urgency. Some…30 June, 2011 by Richard Hindmarsh, Richard Hindmarsh
Ice domes are either axisymmetric, high points along ridges, or ridge triple junctions. We model time-dependent isothermal flow near triple junctions, solving the full set of mechanical equations with a…Read more on Flow at ice-divide triple junctions: 1. Three-dimensional full-Stokes modeling
30 June, 2011 by Ed King, Hugh Corr, Richard Hindmarsh, Robert Mulvaney, Richard Hindmarsh
Ground-based surveys of ice-divide triple junctions in two Antarctic ice rises, the Fletcher Promontory and Berkner Island, have been carried out using low-frequency ice-penetrating radars. These surveys have focused on…27 June, 2011 by Eric Wolff, Howard Roscoe
In the laboratory, we have investigated the growth and composition of frost flowers. Their ionic composition has shown little difference from those of field measurements. Young frost flowers grown on…1 June, 2011 by Hilmar Gudmundsson, Keith Nicholls
Ocean tides under the large Weddell Sea ice shelves are among the least well observed on Earth. Here we present new, spatially extensive observations of the vertical tidal motion of…1 June, 2011 by Richard Hindmarsh, Richard Hindmarsh
In East Antarctica surface mass balance data can only be obtained from the sparsely distributed ice cores when considering time periods greater than a few decades. Observations of internal layers…1 June, 2011 by Nigel Meredith
We perform a comprehensive analysis of resonant scattering of diffuse auroral electrons by oblique nightside chorus emissions present along a field line with an equatorial crossing of 6 R(E) at…1 June, 2011 by Claus-Dieter Hillenbrand
We present results of detailed paleomagnetic investigations on deep-sea cores from sediment drifts located along the Pacific continental margin of the Antarctic Peninsula. High-resolution magnetic measurements on u channel samples…25 May, 2011 by Adrian Jenkins, David Vaughan, Hugh Corr, Hamish Pritchard, Paul Holland, Robert Arthern
The air content of glacial firn determines the effect and attribution of observed changes in ice surface elevation, but is currently measurable only using labor-intensive ground-based techniques. Here a novel…23 May, 2011 by Povl Abrahamsen
This cruise report describes the combined JR252 and JR254C cruise on RRS James Clark Ross, departing Port Stanley on March 19th and arriving in Punta Arenas on April 6th. JR252…Read more on Cruise Report RRS James Clark Ross JR252 & JR254C, 19 March – 6 April 2011
12 May, 2011 by Mark Clilverd
The atmospheric chemistry general circulation model ECHAM5/MESSy is used to simulate polar surface air temperature effects of geomagnetic activity variations. A transient model simulation was performed for the years 1960-2004…1 May, 2011
Sea ice friction models are necessary to predict the nature of interactions between sea ice floes. These interactions are of interest on a range of scales, for example, to predict…1 May, 2011 by Mai Mai Lam, Nigel Meredith, Richard Horne
Electron precipitation from the Earth's inner magnetosphere transmits solar variability to the Earth's upper atmosphere and may affect surface level climate. Here we conduct a superposed epoch analysis of energetic…Read more on Energetic electron precipitation during high-speed solar wind stream driven storms
16 April, 2011 by Mark Clilverd
Utilizing observations from the Medium Energy Proton and Electron Detector (MEPED) on board the Polar Orbiting Environmental Satellite (POES) and the Microwave Limb Sounder (MLS) on board the Aura satellite,…1 April, 2011 by Anna Jones, David Maxfield, Eric Wolff, Howard Roscoe, Markus Frey, Michael Rose, Neil Brough
A suite of 10 autonomous ozone monitoring units, each powered using renewable energy, was developed and built to study surface ozone in Antarctica during the International Polar Year (2007-2009). The…1 April, 2011 by Nigel Meredith, Richard Horne
Using statistical wave power spectral profiles obtained from CRRES and the latitudinal distributions of wave propagation modeled by the HOTRAY code, a quantitative analysis has been performed on the scattering…1 April, 2011 by Nigel Meredith, Richard Horne
Using the statistical wave power spectral profiles obtained from CRRES wave data within the 0000–0600 MLT sector under different levels of geomagnetic activity and a modeled latitudinal variation of wave…1 April, 2011 by Nigel Meredith, Richard Horne
The temporal evolution of the phase space density of plasma sheet electrons (100 eV-30 keV) injected into the nightside at L = 6 during moderate geomagnetic activity is investigated using…27 March, 2011 by Hua Lu
In this study, statistical evidence of a possible modulation of the equatorial stratospheric quasi-biennial oscillation (QBO) by the solar wind dynamic pressure is provided. When solar wind dynamic pressure is…27 March, 2011
This paper describes the use of EOS Microwave Limb Sounder (MLS) data to observe the field of traveling planetary waves with quasi 16 day periods. This study utilizes MLS v2.2…Read more on Properties of the quasi 16 day wave derived from EOS MLS observations
18 March, 2011 by Richard Horne
Energetic proton (1–45 keV) distributions measured by the magnetospheric plasma analyzer detector on Los Alamos National Laboratory geosynchronous orbiting satellites are analyzed to study the characteristics of proton ring development…16 March, 2011 by Anna Jones, Eric Wolff
The concentration of atmospheric methane increased from around 360 ppbv at the last glacial maximum (∼20 ka before present) to about 700 ppbv in the pre-industrial era (∼200 years before…1 March, 2011
The international carbon cycle research community is currently coordinating the largest, most comprehensive assessment it has ever undertaken: the Regional Carbon Cycle Assessment and Processes (RECCAP; http://www.globalcarbonproject.org/reccap). The objective is…Read more on An international effort to quantify regional carbon fluxes
1 March, 2011 by Mark Clilverd
The accepted mechanism for whistler generation implicitly assumes that the causative lightning stroke occurs within reasonable proximity to the conjugate foot point of the guiding magnetic field line and that…Read more on Source region for whistlers detected at Rothera, Antarctica
1 March, 2011 by Mark Clilverd
Observed phases and amplitudes of VLF radio signals propagating on a short (∼360 km) path are used to find improved parameters for the lowest edge of the (D region of…28 January, 2011
On 16–17 July 2007 during an observational campaign at Comandante Ferraz Antarctic Station (62 degrees S, 58 degrees W), a mesospheric wall was observed with an airglow all-sky imager. The…Read more on Case study of a mesospheric wall event over Ferraz station, Antarctica (62° S)
27 January, 2011 by Gareth Chisham, Mervyn Freeman
We report a superposed epoch analysis of the hemispheric open magnetic flux, maximum nightside auroral intensity, geomagnetic activity, and solar wind and interplanetary magnetic field conditions around the time of…27 January, 2011 by Hua Lu, Ingrid Cnossen
We use a troposphere-stratosphere model of intermediate complexity to study the atmospheric response to an idealized solar forcing in the subtropical upper stratosphere during Northern Hemisphere (NH) early winter. We…Read more on Solar signal propagation: The role of gravity waves and stratospheric sudden warmings
1 January, 2011 by Vsevolod Afanasyev
Each autumn billions of songbirds migrate between the temperate zone and tropics, but little is known about how events on the breeding grounds affect migration to the tropics. Here, we…1 January, 2011 by Katrin Linse
Three hundred and fifty specimens of the endemic Southern Ocean octopus genus Pareledone, were sequenced for the barcoding gene COI. Geographic coverage comprised the South Shetland Islands, the Ross Sea,…1 January, 2011 by Claire Allen
Sea-ice growth and decay in Antarctica is one of the biggest seasonal changes on Earth, expanding ice cover from 4 106 km2 to a maximum of 19 106 km2 during…1 January, 2011 by Claire Allen
We have developed cleaning methods for extracting diatomopal from bulk marine sediment samples, for measurement of both zinc (Zn) abundance and isotope composition. This cleaning technique was then applied to…1 January, 2011 by Mark Belchier
Patagonian toothfish (Dissostichus eleginoides) or ‘Chilean sea bass’ support a valuable and controversial fishery, yet their life history is not well understood and longevity estimates range from ~20 to >50…1 January, 2011
A global chemistry-climate model is used to assess the impact on atmospheric composition of the regeneration and recycling of HOx in the photo-oxidation of isoprene. The impact is explored subject…1 January, 2011 by Kevin Hughes
Antarctica is the most isolated continent on Earth, but it has not escaped the negative impacts of human activity. The unique marine ecosystems of Antarctica and their endemic faunas are…Read more on Anthropogenic impacts on marine ecosystems in Antarctica
1 January, 2011 by Eric Wolff
We constructed an 800,000-year synthetic record of Greenland climate variability based on the thermal bipolar seesaw model. Our Greenland analog reproduces much of the variability seen in the Greenland ice…1 January, 2011 by Andrew Clarke, David Barnes
Antarctica is a continent of extremes: on average it is the highest, windiest, coldest and driest land mass on Earth. It also has the largest ice-mass, with less than 1%…1 January, 2011 by David Barnes, Terri Souster, Terri Souster
The West Antarctic Peninsula (WAP) is a hotspot of recent rapid regional warming and ice loss1. The WAP sea surface freezes each winter to form a ‘fast-ice’ skin that can…Read more on Reduced survival of Antarctic benthos linked to climate-induced iceberg scouring
1 January, 2011 by Povl Abrahamsen
Extremely low summer sea-ice coverage in the Arctic Ocean in 2007 allowed extensive sampling and a wide quasi-synoptic hydrographic and δ18O dataset could be collected in the Eurasian Basin and…Read more on Origin of freshwater and polynya water in the Arctic Ocean halocline in summer 2007
1 January, 2011 by Fausto Ferraccioli, Hugh Corr, Tom Jordan
An International Polar Year aerogeophysical investigation of the high interior of East Antarctica reveals widespread freeze-on that drives substantial mass redistribution at the bottom of the ice sheet. Although the…