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Author doi  openurl
  Title How to make robust splitting measurements for single-station analysis and three-dimensional imaging of seismic anisotropy Type Journal Article
  Year 2010 Publication Geophysical Journal International Abbreviated Journal  
  Volume 182 Issue 1 Pages 311 -328  
  Keywords  
  Abstract (down) We quantify errors on splitting intensity measurements produced by incoherent noise on horizontal components through a detailed analysis of synthetic seismograms and of SKS and SKKS waves recorded by four permanent broad-band stations. We find that these errors are quite significant, even on high-quality records, because the measurement procedure involves the comparison of radial and transverse components, which are both contaminated by noise. To decrease the level of noise in the data, it is thus recommended to average splitting intensities from waves coming from the same backazimuth. Alternatively, one can analyse stacked radial and transverse components after applying a Wiener filter, which standardizes the waveforms. This is found to be equivalent because the measure of splitting intensity is a linear process. The utilization of Wiener filters reduces variations of apparent splitting resulting from differences in frequency content of the waveforms. It is possible to determine splitting parameters (splitting delays and fast directions) from azimuthal variations of splitting intensity at a particular station. Tests on synthetic seismograms demonstrate that this approach gives unbiased and robust estimates of splitting parameters, in contrast to the Silver and Chan method, which only works on the rare records that have very large signals on their transverse components. The Wolfe and Silver method does not suffer from this limitation and gives the same results as the multichannel splitting intensity method. Analysis of splitting intensities at stations BDFB, BGCA, CAN and ERM gives fast directions that are generally in excellent agreement with those determined with the Wolfe and Silver method. However, at some stations, azimuthal variations of splitting intensities reveal features that are not well captured by the sinusoidal variation representing the average anisotropy beneath the station. This suggests that small-scale lateral variations of anisotropy are present in the subcontinental mantle, which remain to be imaged in detail.
 
  Programme 133  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0956-540X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 461  
Permanent link to this record
 
 
Author Zalian C, Chadid M, Vernin J, Abe L, Agabi A, doi  openurl
  Title Antarctica photometry of the Blazhko RR Lyrae star S Arae Type Journal Article
  Year 2015 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal  
  Volume 456 Issue 1 Pages 192-206  
  Keywords  
  Abstract (down) We pursue the study of S Arae, an RRab Lyrae Blazho star, using unique, uninterrupted and accurate optical photometric data acquired from Antarctica at Dome C by PAIX – Photometer AntarctIca eXtraction – during 150 d. The PAIX data were analysed using both Period04 and PDM13. Besides a main pulsation period of 0.452 d and a modulation period of 47.264 d, three other significant frequencies were found. Multiplet patterns, up to the ninth order, were also extracted, showing a clear asymmetric structure. Following these results, a new approximation of the main-frequency harmonics amplitude decrease is suggested, replacing the usual exponential fit by a hyperbolic one. The physical properties of the Blazhko star, namely metallicity, temperature, mass, were obtained using a new approach based on the study of these parameters for each Blazhko phase. Finally, the PAIX data reveal a residual scatter that occurs during a small phase interval, 10 per cent of the pulsation period, corresponding to the phase of the main shock passage across the atmosphere. The position of the so-called main bump, corresponding to the shock resulting from the infalling atmosphere and the expanding photosphere, varies from one cycle to another and, moreover, around this main bump, two other bumps appear and vanish at different phases during a Blazhko cycle. Following these observations, we discuss the relation between the bump topology and the Blazhko period and give new insights for future Blazhko theoretical investigations.
 
  Programme 1096  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6247  
Permanent link to this record
 
 
Author Ciais P, Rayner P, Chevallier F, Bousquet P, Logan M, Peylin P, Ramonet M, doi  openurl
  Title Atmospheric inversions for estimating CO2 fluxes: methods and perspectives Type Journal Article
  Year 2010 Publication Climatic Change Abbreviated Journal 0165-0009  
  Volume 103 Issue 1 Pages 69-92  
  Keywords Earth and Environmental Science,  
  Abstract (down) We provide a review description of atmospheric inversion methods for the determination of fluxes of long-lived trace gases based on measurements of atmospheric concentration. Emphasis is given to technical aspects of inversion settings, which are crucial to inter-compare and understand inversion results. We briefly sketch the formalism used in such methods, then provide a summary of major currents in research and contemporary problems. Most attention is given to carbon dioxide (CO 2 ) which poses the threat of future climate change. Therefore, there is keen interest in better understanding where and when CO 2 emitted by the combustion of fossil fuels is reabsorbed by land ecosystems and oceans. Using the information contained in concentration fields observed from ground-based networks and from upcoming satellite observations in order to constrain the geographic distribution of surface fluxes is an inverse problem; it consists of finding a set of fluxes that optimally matches the observations available. We review the application of inverse methods to quantify the distribution of the sources and sinks of CO 2 at the surface of the Earth based on global measurements of atmospheric concentration and three-dimensional models of atmospheric transport. We describe the use of topdown atmospheric inversion methods in terms of numerical transport modeling and atmospheric observation networks, and detail some of the currently important issues in assigning uncertainties.  
  Programme 416  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Springer Netherlands Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0165-0009 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 3127  
Permanent link to this record
 
 
Author Alexander Kokhanovsky, Simon Gascoin, Laurent Arnaud, Ghislain Picard doi  openurl
  Title Retrieval of Snow Albedo and Total Ozone Column from Single-View MSI/S-2 Spectral Reflectance Measurements over Antarctica Type Journal
  Year 2021 Publication Remote Sensing Abbreviated Journal  
  Volume 13 Issue 21 Pages 4404  
  Keywords albedo inverse problems light scattering radiative transfer snow snow grain size  
  Abstract (down)  
  Programme 1110  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2072-4292 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8305  
Permanent link to this record
 
 
Author Lesur Vincent, Rother Martin, Wardinski Ingo, Schachtschneider Reyko, Hamoudi Mohamed, Chambodut Aude, doi  openurl
  Title Parent magnetic field models for the IGRF-12GFZ-candidates Type Journal Article
  Year 2015 Publication Earth, Planets and Space Abbreviated Journal  
  Volume 67 Issue 1 Pages 87-87  
  Keywords  
  Abstract (down)  
  Programme 139  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1343-8832 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6075  
Permanent link to this record
 
 
Author Di Giacomo Domenico, Grosser Helmut, Parolai Stefano, Bormann Peter, Wang Rongjiang, doi  openurl
  Title Rapid determination of Me for strong to great shallow earthquakes Type Journal Article
  Year 2008 Publication Geophys. Res. Lett. Abbreviated Journal  
  Volume 35 Issue 10 Pages L10308-  
  Keywords amplitude decay dunctions, readiated seismic energy, energy magnitude, 7219 Seismology: Seismic monitoring and test-ban treaty verification, 7215 Seismology: Earthquake source observations, 7203 Seismology: Body waves,  
  Abstract (down)  
  Programme 133  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher AGU Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0094-8276 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 2783  
Permanent link to this record
 
 
Author Rochette P., Gattacceca J., Eisenlohr P. & Folco L. file  openurl
  Title In situ magnetic identification and classification of meteorites in Antarctica. Type Journal Article
  Year 2004 Publication Lunar and planetary science Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract (down) We present the results of the use of magnetic methods (susceptibility, magnetic anomalies) applied to meteorite identification and partial classification. These methods were successfully tested during a meteorite collection expedition in Antarctica.  
  Programme 412  
  Campaign  
  Address  
  Corporate Author Thesis Bachelor's thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1540-7845 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 3192  
Permanent link to this record
 
 
Author Haydar Karao?lu, Barbara Romanowicz file  doi
openurl 
  Title Global seismic attenuation imaging using full-waveform inversion: a comparative assessment of different choices of misfit functionals Type Journal
  Year 2018 Publication Geophysical Journal International Abbreviated Journal  
  Volume 212 Issue 2 Pages 807-826  
  Keywords  
  Abstract (down)  
  Programme 133  
  Campaign  
  Address  
  Corporate Author Thesis Bachelor's thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0956-540X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7881  
Permanent link to this record
 
 
Author Armelle Decaulne, Najat Bhiry, Julien Lebrun, Samuel Veilleux, Denis Sarrazin doi  isbn
openurl 
  Title Type Journal
  Year 2018 Publication Abbreviated Journal  
  Volume 0 Issue 0 Pages 1-15  
  Keywords  
  Abstract (down) We present the results of a study of the morphometric properties of a talus slope in subarctic Quebec (Nunavik) using field-based methods, including geomorphological, granulometric and plant distribution surveys, and statistical analyses. Slope processes are currently active, despite the limited altitudinal difference between the apical-to-distal parts of the slope and the imminent depletion of the debris supply. The near-rectilinear long profiles of the talus highlight the distribution of debris across the slope and demonstrate that free-fall of rock fragments is not the only process operating (redistribution is higher in the westernmost profile, which exhibits a clear concave shape). The spatial distribution of vegetation covering the screes highlights the recent age of parts of the talus, showing that present-day processes are still active, although limited. The short remaining apical rockwall highlights the shortage of debris following deglaciation, as debris are mostly supplied by freeze-thaw processes to the talus, and are then reworked by other processes which need to be better defined in subsequent research.  
  Programme 1148  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1195-6860 ISBN 1195-6860 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6778  
Permanent link to this record
 
 
Author Armelle Decaulne, Najat Bhiry, Julien Lebrun, Samuel Veilleux, Denis Sarrazin doi  isbn
openurl 
  Title Type Journal
  Year 2018 Publication Abbreviated Journal  
  Volume 25 Issue 4 Pages 343-357  
  Keywords  
  Abstract (down) We present the results of a study of the morphometric properties of a talus slope in subarctic Quebec (Nunavik) using field-based methods, including geomorphological, granulometric and plant distribution surveys, and statistical analyses. Slope processes are currently active, despite the limited altitudinal difference between the apical-to-distal parts of the slope and the imminent depletion of the debris supply. The near-rectilinear long profiles of the talus highlight the distribution of debris across the slope and demonstrate that free-fall of rock fragments is not the only process operating (redistribution is higher in the westernmost profile, which exhibits a clear concave shape). The spatial distribution of vegetation covering the screes highlights the recent age of parts of the talus, showing that present-day processes are still active, although limited. The short remaining apical rockwall highlights the shortage of debris following deglaciation, as debris are mostly supplied by freeze-thaw processes to the talus, and are then reworked by other processes which need to be better defined in subsequent research.  
  Programme 1148  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1195-6860 ISBN 1195-6860 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7428  
Permanent link to this record
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