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  • Auroral oval boundary locations derived from IMAGE (Imager for Magnetopause-to-Aurora Global Exploration) satellite FUV (Far Ultra Violet imager) data covering the period from May 2000 until October 2002. Three sets of boundary data were derived separately from the WIC (Wideband Imaging Camera) and SI12/SI13 (Spectrographic Imager 121.8/135.6 nm) detectors. For each image, the position of each pixel in AACGM (Altitude Adjusted Corrected Geomagnetic) coordinates was established. Each image was then divided into 24 segments covering 1 hour of magnetic local time (MLT). For each MLT segment, an intensity profile was constructed by finding the average intensity across bins of 1 degree magnetic latitude in the range of 50 to 90 degrees (AACGM). Two functions were fit to each intensity profile: a function with one Gaussian component and a quadratic background, and a function with two Gaussian components and a quadratic background. The function with a single Gaussian component should provide a reasonable model when the auroral emission forms in a continuous oval. When the oval shows bifurcation, the function with two Gaussian components may provide a better model of the auroral emission. Of the two functions fit to each intensity profile, we determine the one with the lower reduced chi-square goodness-of-fit statistic to be the better model for that profile. For the version 1.1 boundary location data, the fitting process was performed over 200 iterations to achieve each fit. The auroral boundaries were then determined to be the position of the peak of the poleward Gaussian curve, plus its FWHM (full-width half-maximum) value of the Gaussian, to the peak of the equatorward Gaussian, minus its FWHM. In the case of the single Gaussian fit, the same curve is used for both boundaries. A number of criteria were applied to discard poorly located auroral boundaries arising from either poor fitting or incomplete data. A further correction can be applied to the data, to estimate the location of the Earth''s magnetic field''s OCB (open-close boundary). These corrections have been tabulated in a separate file; if this correction is required the adjustments should be made to the poleward boundary value.

  • We present a new bathymetric compilation of the greater South Georgia region, here defined by a bounding box of ~900km (45W to 19W) by ~580km (63S to 50S) and covering an area of 530,000 km2. The region includes the South Georgia shelf, the Shag Rock shelf (to the west of South Georgia), the surrounding continental slopes and adjacent deep sea. This bathymetry grid was compiled from a variety of different data sources including multibeam swath bathymetry collected from scientific cruises undertaken by British Antarctic Survey (BAS), Alfred Wegener Institute (AWI) and the Institute of Geophysics, University of Texas. The grid has been constructed using a layered hierarchy dependent on accuracy of each dataset. The data is available as a 100m resolution GeoTIFF, ESRI ascii grid or KMZ file of elevation data along with a shapefile indicating the spatial coverage of all the contributing datasets. This work was supported by the National Environmental Research Council (grant number NE/L002531/1). For further information regarding the creation of this dataset please refer to doi:10.1038/srep33163.

  • Model output from a series of idealised ice shelf-ocean simulations, demonstrating a new synchronously coupled modelling method as well as the response of ice shelf buttressing to melt under various temperature forcings.

  • The Antarctic mass trends have been collated from a combination of different remote sensing datasets. These are trends of yearly elevation changes over Antarctica for the period 2003-2013 due to the different geophysical processes driving changes in Antarctica: ice dynamics, surface mass balance and glacio-isostatic adjustment (GIA). Net trends can be easily calculated by adding together surface and ice dynamics trends. 20 km gridded datasets have been produced for each process, per year (except the GIA solution which is time-invariant). To convert elevation to mass trends, we also provide the density fields for surface (SMB) and GIA processes used in Martin-Espanol et al (2016). These can be directly multiplied by the dh/dt. To convert dh/dt from ice dynamics, simply multiply by the density of ice. Mass smb = dh/dt smb * d surf Mass ice = dh/dt ice * d ice (not provided) Mass gia = dh/dt gia * d rock NERC grant: NE/I027401/1

  • This is a collection of GPS data from dual-frequency GPS units deployed on the Filchner-Ronne Ice Shelf and adjoining ice streams. Filenames contain ice stream code and, in some cases, where the ice stream code is followed by a plus or minus sign, the approximate distance in kilometres upstream from the ice stream''s grounding line, although in other cases the number is arbitrary. The naming convention has been preserved for legacy reasons. The ice streams are Evans (E & XX), Rutford (R), Institute (IIS), Talutis (T & TT) and Foundation (H) ice streams. Each GPS unit''s data are given in a netCDF4_classic file containing 4 columns: "Date number", as the number of days from January 0, 0000 in the proleptic ISO calendar; "Latitude" & "Longitude", both in decimal degrees in the WGS 1984 EPSG:4326 co-ordinate system; "height", in metres above the reference ellipsoid. The data have been collated from daily files, processed using the Bernese 5.0 software, using precise point positioning at intervals of 30 seconds. Note that data have not been corrected for inverse barometer or ocean tide loading effects. These data were collected as part of a systemic campaign to look for modulation in ice flow through ocean tidal forcing. The vertical tidal motion of floating ice shelves generates stresses which cause a change in horizontal ice velocity at periods of hours to years. These signals can travel far upstream of ice stream grounding lines and often exhibit a change in frequency from the astronomical tides that generate them. As such, they can act as a natural experiment with which we can learn about ice rheology and subglacial processes.

  • This data was gathered to study the effects of combined environmental stressors of lowered pH and increased temperature on the adult metabolism and larval development of the Antarctic sea urchin, S. neumayeri. Specimens were cultured under the combined environmental stressors of lowered pH (-0.3 and -0.5 pH units) and increased temperature (+2 degrees C). The experiment took place over a two-year period, from June 2009, covering two full reproductive cycles of this species. The dataset is divided into adult and offspring. Data for adult S. neumayeri are given at four-monthly intervals. Values provided include oxygen consumption (umols), whole animal wet and dry mass (g), test diameter and thickness (mm), gonad wet and dry tissue mass (g), AFDM (Ash-Free Dry Mass) (g), CaCO3, and gonad index (GI%). Mean frequencies are also provided for larval development stages (%) for 25-day-old S. neumayeri offspring. These offspring are derived from larval cultures spawned after 6 and 17 months exposure to altered pH and temperature conditions. Postoral arm length measurements for the most advanced larvae is also provided as a metric of skeletal development. Two tables relating to seawater chemistry measurements are also provided. Table 1 displays mean water parameters in the adult S. neumayeri microcosm over the course of the experiment. Supplementary Table 1 gives mean seawater parameters of the S. neumayeri larval cultures derived from parents pre-exposed to low temperature and high temperature seawater controls and lowered carbonate conditions.

  • This dataset provides a 308 year (1702-2009) deuterium isotope record from the Ferrigno 2010 (F10) ice core. The core was drilled on the Bryan Coast in Ellsworth Land, West Antarctica, during the austral summer 2010/11. The record was measured using a Los Gatos Liquid Water Isotope Analyser at 5cm resolution, corresponding to ~14 samples per year, with annual averages calculated for January-December. Funding was provided by the NERC grant NE/J020710/1

  • Measurements of water discharge, suspended sediment concentration and electrical conductivity during the melt seasons of 2009, 2010, 2011 and 2012 in the proglacial river draining from the tongue of Leverett Glacier, a land-terminating glacier in the south-west of the Greenland Ice Sheet. The measurements were made in a stable bedrock section approximately 2 km downstream from the glacier terminus. Data loggers recorded measurements every 15 minutes from approximately May to August each year. Water depth (stage) was converted to discharge (Q) using season-specific ratings curves derived from repeat dye-dilution injections undertaken across the stage values. Suspended sediment concentration (SSC) was obtained by calibrating turbidity sensor readings with sediment samples taken in-situ and then filtered, dried and weighed. Electrical conductivity (EC) was recorded using a water conductivity probe; the data were filtered for bad values and corrected for temperature, but no smoothing was applied. These version 2 files are presented as CSV lists, with some summary metadata included as comments at the start of each file; they essentially contain the same data as the previous version files.

  • The data consists of proxy data with associated ages from six moss bank cores from four locations on the Antarctic Peninsula. Proxies included are: 13C, microbial productivity (derived from testate amoeba concentration values), mass accumulation rate and moss growth rate. Sites are Elephant Island (core ELE3), Ardley Island (cores ARD1 and ARD3) and Green Island (cores GRE1 and GRE2). Elephant Island (61.111 S, 54.824 W) and Ardley Island (62.213 S, 58.935 W) cores were collected in January 2012. Green Island (65.322 S, 64.151 W) cores were collected in January 2013. Funding was provided by the NERC grants NE/H014896/1, NE/H014632/1 and NE/H014810/1.

  • Version 2.0 This data set contains mesospheric carbon monoxide (CO) data acquired by the ground-based microwave radiometer of the British Antarctic Survey (BAS radiometer) stationed at Troll station in Antarctica (72 deg S, 2.5 deg E, 1270 amsl). The BAS radiometer has been designed in order to study the effects of energetic particle precipitation on the middle and upper atmosphere, using nitric oxide and ozone measurements. This data set contains the CO measurements carried out in order to study the dynamical context. The data set covers the period from February 2008 to January 2010, however, due to very low CO concentrations below approximately 80 km altitude in summer, profiles can only be retrieved during Antarctic winter. CO is measured for approximately 2 hours each day (80 percent of the profiles are within +-2 hours around local noon) and profiles are retrieved approximately every half hour. The retrieved profiles, cover two independent layers in the pressure range from 1 to 0.01 hPa (approximately 48 to 80 km, altitude resolution of approximately 16 km). In this version of the data; an additional column of "apriori vmr" has been included in the data files.