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Author Gronoff G, Lilensten J, Desorgher L, Flückiger E, doi  openurl
  Title Ionization processes in the atmosphere of Titan Type Journal Article
  Year 2009 Publication A&A Abbreviated Journal  
  Volume 506 Issue 2 Pages 955 -964  
  Keywords (down) planets and satellites: individual: Titan -- atmospheric effects -- Sun: UV radiation -- space vehicles: instruments -- methods: numerical  
  Abstract Context. The Cassini probe regularly passes in the vicinity of Titan, revealing new insights into particle precipitation thanks to the electron and proton spectrometer. Moreover, the Huygens probe has revealed an ionized layer at 65 km induced by cosmic rays. The impact of these different particles on the chemistry of Titan is probably very strong.
Aims. In this article, we compute the whole ionization in the atmosphere of Titan: from the cosmic rays near the ground to the EUV in the upper atmosphere. The meteoritic layer is not taken into account.
Methods. We used the transTitan model to compute the electron and EUV impact, and the planetocosmics code to compute the influence of protons and oxygen ions. We coupled the two models to study the influence of the secondary electrons obtained by planetocosmics through the transTitan code. The resulting model improves the accuracy of the calculation through the transport of electrons in the atmosphere.
Results. The whole ionization is computed and studied in details. During the day, the cosmic ray ionization peak is as strong as the UV-EUV one. Electrons and protons are very important depending the precipitation conditions. Protons can create a layer at 500 km, while electrons tend to ionize near 800 km. The oxygen ion impact is near 900 km. The results shows few differences to precedent models for the nightside T5 fly-by of Cassini, and can highlight the sources of the different ion layers detected by radio measurements.
Conclusions. The new model successfully computes the ion production in the atmosphere of Titan. For the first time, a full electron and ion profile has been computed from 0 to 1600 km, which compares qualitatively with measurements. This result can be used by chemical models.
 
  Programme 1026  
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  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 0004-6361 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 1973  
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Author Piat M, Battistelli E, Baù A, Bennett D, Bergé L, Bernard J-P, de Bernardis P, Bigot-Sazy M-A, Bordier G, Bounab A, Bréelle E, Bunn E, Calvo M, Charlassier R, Collin S, Cruciani A, Curran G, Dumoulin L, Gault A, Gervasi M, Ghribi A, Giard M, Giordano C, Giraud-Héraud Y, Gradziel M, Guglielmi L, Hamilton J-C, Haynes V, Kaplan J, Korotkov A, Landé J, Maffei B, Maiello M, Malu S, Marnieros S, Martino J, Masi S, Montier L, Murphy A, Nati F, OSullivan C, Pajot F, Parisel C, Passerini A, Peterzen S, Piacentini F, Piccirillo L, Pisano G, Polenta G, Prêle D, Romano D, Rosset C, Salatino M, Schillaci A, Sironi G, Sordini R, Spinelli S, Tartari A, Timbie P, Tucker G, Vibert L, Voisin F, Watson R, Zannoni M, doi  openurl
  Title QUBIC: the Q&U Bolometric Interferometer for Cosmology Type Conference - International - Article with Reading Comitee
  Year 2011 Publication Journal of Low Temperature Physics Abbreviated Journal  
  Volume Issue Pages 1-7  
  Keywords (down) Physics and Astronomy,  
  Abstract The primordial B-mode polarisation of the Cosmic Microwave Background is the imprints of the gravitational wave background generated by inflation. Observing the B-mode is up to now the most direct way to constrain the physics of the primordial Universe, especially inflation. To detect these B-modes, high sensitivity is required as well as an exquisite control of systematics effects. To comply with these requirements, we propose a new instrument called QUBIC (Q and U Bolometric Interferometer for Cosmology) based on bolometric interferometry. The control of systematics is obtained with a close-packed interferometer while bolometers cooled to very low temperature allow for high sensitivity. We present the architecture of this new instrument, the status of the project and the self-calibration technique which allows accurate measurement of the instrumental systematic effects.  
  Programme 915  
  Campaign  
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  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 0022-2291 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 3482  
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Author Klein K-L, Trottet G, Samwel S, Malandraki O, doi  openurl
  Title Particle Acceleration and Propagation in Strong Flares without Major Solar Energetic Particle Events Type Journal Article
  Year 2011 Publication Solar Physics Abbreviated Journal  
  Volume 269 Issue 2 Pages 309-333  
  Keywords (down) Physics and Astronomy,  
  Abstract Solar energetic particles (SEPs) detected in space are statistically associated with flares and coronal mass ejections (CMEs). But it is not clear how these processes actually contribute to the acceleration and transport of the particles. The present work addresses the question why flares accompanied by intense soft X-ray bursts may not produce SEPs detected by observations with the GOES spacecraft. We consider all X-class X-ray bursts between 1996 and 2006 from the western solar hemisphere. 21 out of 69 have no signature in GOES proton intensities above 10 MeV, despite being significant accelerators of electrons, as shown by their radio emission at cm wavelengths. The majority (11/20) has no type III radio bursts from electron beams escaping towards interplanetary space during the impulsive flare phase. Together with other radio properties, this indicates that the electrons accelerated during the impulsive flare phase remain confined in the low corona. This occurs in flares with and without a CME. Although GOES saw no protons above 10 MeV at geosynchronous orbit, energetic particles were detected in some (4/11) confined events at Lagrangian point L1 aboard ACE or SoHO. These events have, besides the confined microwave emission, dm-m wave type II and type IV bursts indicating an independent accelerator in the corona. Three of them are accompanied by CMEs. We conclude that the principal reason why major solar flares in the western hemisphere are not associated with SEPs is the confinement of particles accelerated in the impulsive phase. A coronal shock wave or the restructuring of the magnetically stressed corona, indicated by the type II and IV bursts, can explain the detection of SEPs when flare-accelerated particles do not reach open magnetic field lines. But the mere presence of these radio signatures, especially of a metric type II burst, is not a sufficient condition for a major SEP event.  
  Programme 227  
  Campaign  
  Address  
  Corporate Author Thesis Bachelor's 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 0038-0938 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 3577  
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Author Saintenoy Albane, Friedt J-M, Booth Adam D, Tolle F, Bernard E, Laffly Dominique, Marlin C, Griselin M, openurl 
  Title Deriving ice thickness, glacier volume and bedrock morphology of the Austre Lovénbreen (Svalbard) using Ground-penetrating Radar Type Journal Article
  Year 2013 Publication NEAR SURFACE GEOPHYSICS Abbreviated Journal  
  Volume 11 Issue Pages 253-261  
  Keywords (down) Physics – Geophysics,  
  Abstract The Austre Lov\'enbreen is a 4.6 km2 glacier on the Archipelago of Svalbard (79 degrees N) that has been surveyed over the last 47 years in order of monitoring in particular the glacier evolution and associated hydrological phenomena in the context of nowadays global warming. A three-week field survey over April 2010 allowed for the acquisition of a dense mesh of Ground-penetrating Radar (GPR) data with an average of 14683 points per km2 (67542 points total) on the glacier surface. The profiles were acquired using a Mala equipment with 100 MHz antennas, towed slowly enough to record on average every 0.3 m, a trace long enough to sound down to 189 m of ice. One profile was repeated with 50 MHz antenna to improve electromagnetic wave propagation depth in scattering media observed in the cirques closest to the slopes. The GPR was coupled to a GPS system to position traces. Each profile has been manually edited using standard GPR data processing including migration, to pick the reflection arrival time from the ice-bedrock interface. Snow cover was evaluated through 42 snow drilling measurements regularly spaced to cover all the glacier. These data were acquired at the time of the GPR survey and subsequently spatially interpolated using ordinary kriging. Using a snow velocity of 0.22 m/ns, the snow thickness was converted to electromagnetic wave travel-times and subtracted from the picked travel-times to the ice-bedrock interface. The resulting travel-times were converted to ice thickness using a velocity of 0.17 m/ns. The velocity uncertainty is discussed from a common mid-point profile analysis. A total of 67542 georeferenced data points with GPR-derived ice thicknesses, in addition to a glacier boundary line derived from satellite images taken during summer, were interpolated over the entire glacier surface using kriging with a 10 m grid size. Some uncertainty analysis were carried on and we calculated an averaged ice thickness of 76 m and a maximum depth of 164 m with a relative error of 11.9%. The volume of the glacier is derived as 0.3487$\pm$0.041 km3. Finally a 10-m grid map of the bedrock topography was derived by subtracting the ice thicknesses from a dual-frequency GPS-derived digital elevation model of the surface. These two datasets are the first step for modelling thermal evolution of the glacier and its bedrock, as well as the main hydrological network.  
  Programme 1111  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1569-4445 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 4429  
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Author Lia Siegelman, Patrice Klein, Pascal Rivière, Andrew F. Thompson, Hector S. Torres, Mar Flexas, Dimitris Menemenlis file  doi
isbn  openurl
  Title Enhanced upward heat transport at deep submesoscale ocean fronts Type Journal
  Year 2020 Publication Nature Geoscience Abbreviated Journal  
  Volume 13 Issue 1 Pages 50-55  
  Keywords (down) Physical oceanography  
  Abstract The ocean is the largest solar energy collector on Earth. The amount of heat it can store is modulated by its complex circulation, which spans a broad range of spatial scales, from metres to thousands of kilometres. In the classical paradigm, fine oceanic scales, less than 20 km in size, are thought to drive a significant downward heat transport from the surface to the ocean interior, which increases oceanic heat uptake. Here we use a combination of satellite and in situ observations in the Antarctic Circumpolar Current to diagnose oceanic vertical heat transport. The results explicitly demonstrate how deep-reaching submesoscale fronts, with a size smaller than 20 km, are generated by mesoscale eddies of size 50–300 km. In contrast to the classical paradigm, these submesoscale fronts are shown to drive an anomalous upward heat transport from the ocean interior back to the surface that is larger than other contributions to vertical heat transport and of comparable magnitude to air–sea fluxes. This effect can remarkably alter the oceanic heat uptake and will be strongest in eddy-rich regions, such as the Antarctic Circumpolar Current, the Kuroshio Extension and the Gulf Stream, all of which are key players in the climate system.  
  Programme 109,1201  
  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 1752-0908 ISBN 1752-0908 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8264  
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Author M. Afroosa, B. Rohith, Arya Paul, Fabien Durand, Romain Bourdallé-Badie, P. V. Sreedevi, Olivier de Viron, Valérie Ballu, S. S. C. Shenoi doi  openurl
  Title Madden-Julian oscillation winds excite an intraseasonal see-saw of ocean mass that affects Earth’s polar motion Type Journal
  Year 2021 Publication Communications Earth & Environment Abbreviated Journal  
  Volume 2 Issue 1 Pages 1-8  
  Keywords (down) Physical oceanography  
  Abstract Strong large-scale winds can relay their energy to the ocean bottom and elicit an almost immediate intraseasonal barotropic (depth independent) response in the ocean. The intense winds associated with the Madden-Julian Oscillation over the Maritime Continent generate significant intraseasonal basin-wide barotropic sea level variability in the tropical Indian Ocean. Here we show, using a numerical model and a network of in-situ bottom pressure recorders, that the concerted barotropic response of the Indian and the Pacific Ocean to these winds leads to an intraseasonal see-saw of oceanic mass in the Indo-Pacific basin. This global-scale mass shift is unexpectedly fast, as we show that the mass field of the entire Indo-Pacific basin is dynamically adjusted to Madden-Julian Oscillation in a few days. We find this large-scale ocean see-saw, induced by the Madden-Julian Oscillation, has a detectable influence on the Earth’s polar axis motion, in particular during the strong see-saw of early 2013.  
  Programme 688  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2662-4435 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8387  
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Author Houser C, Masters G, Flanagan M, Shearer P, doi  openurl
  Title Determination and analysis of long-wavelength transition zone structure using SS precursors Type Journal Article
  Year 2008 Publication Geophysical Journal International Abbreviated Journal 0956-540X  
  Volume 174 Issue 1 Pages 178-194  
  Keywords (down) Phase transitions, Body waves,  
  Abstract Global mapping of 410 and 660 km discontinuity topography and transition zone thickness has proven to be a powerful tool for constraining mantle chemistry, dynamics and mineralogy. Numerous seismic and mineral physics studies suggest that the 410 km discontinuity results from the phase change of olivine to wadsleyite and the 660 km discontinuity results from the phase change of ringwoodite to perovskite and magnesiowustite. Underside reflections of the 410 and 660 km discontinuities arrive as precursors to SS. With the recent development of a semi-automated method of determining SS arrivals, we have more than tripled the Flanagan and Shearer (1998a) data set of handpicked SS waveforms. We are able to increase resolution by stacking waveforms in 5° rather than 10° radius bins as well as increasing data coverage significantly in the southern hemisphere. The resulting SS-S410S and SS-S660S times are heavily influenced by upper-mantle velocity structure. We perform a joint inversion for discontinuity topography and velocity heterogeneity as well as performing a simple velocity correction to the precursor differential times and find little difference between the two methods. The 660 km discontinuity topography and transition zone thickness are correlated with velocities in the transition zone whereas the 410 km discontinuity topography is not. In addition, the 410 km discontinuity topography is not correlated with the 660 km discontinuity topography, rather anticorrelated, as expected due to the opposite signs of the Clapeyron slopes of their respective phase changes. These results suggest that, whereas the topography of 660 km discontinuity could be dominated by thermal effects, the topography of the 410 km discontinuity is likely dominated by compositional effects. In addition, unlike previous studies which find less topography on the 410 km discontinuity than on the 660 km discontinuity, our 410 and 660 km topography have similar amplitudes.
 
  Programme 133  
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  Corporate Author Thesis  
  Publisher Blackwell Publishing Ltd Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1365-246X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 2784  
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Author White C R, Green J A, Martin G R, Butler P J, Grémillet D, doi  openurl
  Title Energetic constraints may limit the capacity of visually guided predators to respond to Arctic warming Type Journal Article
  Year 2013 Publication Journal of Zoology Abbreviated Journal J. Zool. (Lond.)  
  Volume 289 Issue 2 Pages 119-126  
  Keywords (down) Phalacrocorax carbo, great cormorant, climate change, temperature, illumination, diving,  
  Abstract For many polar species, climate change is likely to result in range contractions and negative population trends. For those species whose distribution is limited by sea ice and cold water, however, polar warming could result in population increases and range expansion. Population increases of great cormorants Phalacrocorax carbo in Greenland are associated with warmer sea surface temperatures, but the actual impact of environmental change on cormorant spatial ecology remains unclear. In the present study, we investigate how Arctic warming is likely to influence the distribution of cormorants in Greenland. Using geolocation data, we show that many individuals that breed above the Arctic Circle migrate south and winter at lower latitude. We then couple estimates of migratory flight costs with a model that predicts daily energy expenditure during winter on the basis of water temperature, ambient illumination during diving, dive depth and day length. This model shows that the most energy efficient strategy predicted for any breeding location is to migrate as far south as possible, and that, for a given wintering location, it is more energetically expensive to breed at high latitude. We argue that cormorants currently undertake a winter migration to escape the polar night and reduce winter energy costs and that their wintering grounds in Greenland will remain largely unchanged under Arctic warming. This is because low levels of ambient illumination during the polar night will continue to restrict foraging opportunities at high latitude during winter. Northward expansion of the breeding range will result in increased energy expenditure associated with long migratory flights, and the cost of such flights may ultimately limit the breeding range of cormorants. Such limitations are likely to represent a general constraint on the capacity of visually guided predators to respond to climate warming, and may limit the predicted poleward range shifts of these species.
 
  Programme 388  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1469-7998 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 3940  
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Author Moine B. openurl 
  Title Les enclaves ultramafiques-mafiques riches en volatils de Kerguelen (TAAF, Océan Indien), transferts de fluides et métasomatisme mantellique en contexte intraplaque océanique. Etude pétrologique, géochimique (LAM-ICP-MS) et isotopique (O, C, H) = Volatile-bearing ultramafic to mafic xenoliths from the Kerguelen archipelago (TAAF, Southern Indian Ocean), Fluids migration and mantle metasomatism within oceanic intraplate setting. A petrological, geochemical (LAM-ICP-MS) and isotopic (O, C, H) study Type Thesis
  Year 2000 Publication Abbreviated Journal  
  Volume Issue Pages 290  
  Keywords (down) petrogenesis ; rock inclusions ; ultramafics ; volatile elements ; Kerguelen Islands ; metasomatism ; mantle ; mass transfer ; intraplate magmatism ; petrology ; chemical analysis ; mass spectroscopy ; inductively coupled plasma ; stable isotopes ; C-13/C-12 ; O-18/O-16 ; D/H ; trace-element analyses ; xenoliths ; hot spots ; crystal chemistry ; mineral data ; percolation ; fluid phase ; lava ; peridotites ; alkali basalts ; plutonic rocks ; igneous rocks ; Indian Ocean ; basalts ; volcanic rocks  
  Abstract Thèse en sciences de la Terre, Université Jean Monnet, St Etienne

La collection d'enclaves ultramafiques-mafiques des îles Kerguelen est l'une des plus diversifiée du contexte intraplaque océanique et a servi de support à l'étude des fluides, marqueur du métasomatisme mantellique associé à un point chaud. Ces enclaves sont caractérisées par une relative abondance en phases hydroxylées (amphiboles, micas) et carbonatées. Des basaltes alcalins, contenant des mégacristaux d'amphibole et de mica, ont également été étudiés. L'étude pétrologique et géochimique détaillée (cristallochimie, isotopes stables : O, C, H ; éléments en traces-LAM-ICP-MS) a mis en évidence le rôle et la nature des fluides percolants le manteau et la croûte profonde. Ils sont d'origine mantellique et liés à la dernière activité magmatique alcaline attribuée au panache de Kerguelen. Les compositions chimiques particulièrement riches en TiO2 des amphiboles et des micas ont permis de préciser les conditions de stabilisation de ces silicates à haute température. Les amphiboles, les micas et les carbonates ont conservé des signatures isotopiques (O, H, C) de haute température et relativement homogènes. Les signatures isotopiques de l'hydrogène montrent une distribution bimodale qui traduit pour une même température, l'existence de 2 fluides mantelliques différents. Les carbonates présents dans les laves et les péridotites de Kerguelen ont des compositions isotopiques (C, O) strictement péridotitiques et ne montrent à priori aucune évidence d'un composant lithosphérique recyclé. Les phases hydroxylées constituent des réservoirs préférentiels pour les HFSE et les LILE. Les coefficients de partages interminéraux et minéraux/magma ont pu être précisés pour un grand nombre d'éléments (25). Dans les liquides magmatiques percolants, la cristallisation des phases hydroxylées entraîne une forte augmentation du rapport CO2/H2O dans les magmas résiduels. Ceux-ci peuvent former, in fine, un fluide riche en carbonates responsable du métasomatisme des péridotites à carbonates et apatite.
 
  Programme 251  
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  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 1486  
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Author Tartu Sabrina, Angelier Frédéric, Herzke Dorte, Moe Børge, Bech Claus, Gabrielsen Geir W, Bustnes Jan Ove, Chastel Olivier, doi  openurl
  Title The stress of being contaminated? Adrenocortical function and reproduction in relation to persistent organic pollutants in female black legged kittiwakes Type Journal Article
  Year 2014 Publication Science of The Total Environment Abbreviated Journal  
  Volume Issue Pages 553-560  
  Keywords (down) Persistent organic pollutants, Corticosterone, Stress response, Reproduction, Arctic seabirds,  
  Abstract  
  Programme 330  
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  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 0048-9697 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 5655  
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