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Author Rivier, L.; Ciais, P.; Hauglustaine, D.A.; Bakwin, P.; Bousquet, P.; Peylin, P.; Klonecki, A.
Title Evaluation of SF6, C2Cl4, and CO to approximate fossil fuel CO2 in the Northern Hemisphere using a chemistry transport model Type Journal Article
Year 2006 Publication Journal of geophysical research-atmospheres Abbreviated Journal J. Geophys. Res.
Volume 111 Issue Pages
Keywords fossil fuel proxy; SF 6; C 2 Cl 4; CO; carbon fluxes; emissions; 0322 Atmospheric Composition and Structure: Constituent sources and sinks; 0368 Atmospheric Composition and Structure: Troposphere: constituent transport and chemistry; 0365 Atmospheric Composition and Structure: Troposphere: composition and chemistry; 0345 Atmospheric Composition and Structure: Pollution: urban and regional
Abstract The distribution of the fossil fuel component in atmospheric CO2 cannot be measured directly at a cheap cost. Could anthropogenic tracers with source patterns similar to fossil fuel CO2 then be used for that purpose? Here we present and evaluate a methodology using surrogate tracers, CO, SF6, and C2Cl4, to deduce fossil fuel CO2. A three-dimensional atmospheric chemistry transport model is used to simulate the relationship between each tracer and fossil fuel CO2. In summertime the regression slopes between fossil fuel CO2 and surrogate tracers show large spatial variations for chemically active tracers (CO and C2Cl4), although C2Cl4 presents less scatter than CO. At two tall tower sites in the United States (WLEF, Wisconsin, and WITN, North Carolina), we found that in summertime the C2Cl4 (CO) versus fossil CO2 slope is on average up to 15% (25%) higher than in winter. We show that for C2Cl4 this seasonal variation is due to OH oxidation. For CO the seasonal variation is due to both chemistry and mixing with nonanthropogenic CO sources. In wintertime the three surrogate tracers SF6, C2Cl4, and CO are about equally as good indicators of the presence of fossil CO2. However, our model strongly underestimates the variability of SF6 at both towers, probably because of unaccounted for emissions. Hence poor knowledge of emission distribution hampers the use of SF6 as a surrogate tracer. From a practical point of view we recommend the use of C2Cl4 as a proxy of fossil CO2. We also recommend the use of tracers to separate fossil CO2. Despite the fact that the uncertainty on the regression slope is on the order of 30%, the tracer approach is likely to have less bias than when letting one model with one inventory emission map calculate the fossil CO2 distribution.
Programme 439
Campaign
Address
Corporate Author Thesis
Publisher American Geophysical Union Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5588
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Author Thuillier, G.; Perrin, J.-M.; Lathuillère, C.; Hersé, M.; Fuller-Rowell, T.; Codrescu, M.; Huppert, F.; Fehrenbach, M.
Title Dynamics in the polar thermosphere after the coronal mass ejection of 28 October 2003 observed with the EPIS interferometer at Svalbard Type Journal Article
Year 2005 Publication Journal of geophysical research-atmospheres Abbreviated Journal J. Geophys. Res.
Volume 110 Issue Pages
Keywords thermosphere; CME; neutral winds; EPIS; ESR; 0310 Atmospheric Composition and Structure: Airglow and aurora; 0358 Atmospheric Composition and Structure: Thermosphere: energy deposition; 7513 Solar Physics, Astrophysics, and Astronomy: Coronal mass ejections
Abstract The upper atmosphere dynamics in the polar cap is mainly driven by ion-drag momentum sources imposed by the mapping of magnetosphere convection into the thermosphere/ionosphere and by Joule and auroral particle heating. Auroral particles also enhance conductivity particularly in the middle and lower ionosphere. Changes in the magnetospheric energy and momentum sources can significantly modify the wind circulation during geomagnetic storms. To observe these effects, a Michelson interferometer has been installed in Svalbard to measure winds in the thermosphere. Prior to 30 October 2003, cloud cover over Svalbard rendered the conditions unfavorable for optical observation. However, meteorological conditions improved after this date to enable the thermospheric response to the 28 October coronal mass ejection to be made. During quiet geomagnetic conditions measured wind velocities were in good agreement with those predicted by the Horizontal Wind Model (HWM). During disturbed geomagnetic conditions, HWM tended to underestimate the observed velocities. Comparison of the wind observations with a physical model tended to show reasonable agreement during both the strongly driven and recovery phase of the storm. Although the physical model did not always capture the timing of the rapid changes in the wind response in the early phase of the storm, the amplitudes of the fluctuations were in good agreement. After the initial phase the physical model agreed well with both the timing and amplitude of the meridional and zonal wind fluctuations. The meridional wind component was also derived from the EISCAT Svalbard Radar ion velocity and was found to be in close agreement with the optical winds observations.
Programme 384
Campaign
Address
Corporate Author Thesis
Publisher American Geophysical Union Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5585
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Author Landais, A.; Steffensen, J.P.; Caillon, N.; Jouzel, J.; Masson-Delmotte, V.; Schwander, J.
Title Evidence for stratigraphic distortion in the Greenland Ice Core Project (GRIP) ice core during Event 5e1 (120 kyr BP) from gas isotopes Type Journal Article
Year 2004 Publication Journal of geophysical research-atmospheres Abbreviated Journal J. Geophys. Res.
Volume 109 Issue Pages
Keywords 1827 Hydrology: Glaciology; 3344 Meteorology and Atmospheric Dynamics: Paleoclimatology; 3349 Meteorology and Atmospheric Dynamics: Polar meteorology
Abstract The disturbed stratigraphy of the ice in the lowest 10% of the Greenland GRIP ice core has been previously demonstrated using gas measurements (?18O of O2 and CH4) on a few meters depth scale. However, rapid ice isotopic variations (on the scale of 20 cm) are experienced in the bottom of the GRIP ice core with complex chemical signatures that make them difficult to reconcile with a disturbed stratigraphy of the ice. This is the case for event 5e1, first described as a dramatic cooling 120 kyr BP. We analyzed at a 5 cm resolution the isotopic composition of the air from 2 m of the GRIP bottom ice core covering event 5e1. The ?15N measurements, combined with a basic firn modeling, lead to the solid conclusion that the rapid event 5e1 is not a climatic event. Rapid variations of ?18O of O2 (?18Oatm) are in agreement with a disturbed ice stratigraphy. However, the double peak shape of the ?18Oatm, recalling chemical data at the same depth, requires processes of diffusion after the mixing or even postcoring, placing limits to the interpretation of some classical paleoclimatic proxies in small scale mixed ice (<1 m).
Programme 458
Campaign
Address
Corporate Author Thesis
Publisher American Geophysical Union Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5647
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Author Gallée, H.; Pettré, P.; Schayes, G.
Title Sudden Cessation of Katabatic Winds in Adélie Land, Antarctica Type Journal Article
Year 1996 Publication Journal of Applied Meteorology Abbreviated Journal
Volume 35 Issue 7 Pages 1142-1152
Keywords
Abstract The evolution of summer katabatic wind events over the steep slopes of Adélie Land is examined, with emphasis on the sudden cessation of these events. Different idealized large-scale forcings are considered, including a situation that comes very close to one observed during the IAGO (Interaction Atmosphère Glace Océan) campaign, held in the region in November–December 1985. The hydrostatic meso-?-scale atmospheric model MAR (Modèle Atmosphérique Régional) is used to assess the sensitivity of the simulated cessation process to a prescribed large-scale forcing.
Programme 211
Campaign
Address
Corporate Author Thesis
Publisher NOAA Central Library, Department of Commerce Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1520-0450 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5556
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Author Park, Y.-H.; Roquet, F.; Vivier, F.
Title Quasi-stationary ENSO wave signals versus the Antarctic Circumpolar Wave scenario Type Journal Article
Year 2004 Publication Geophysical research letters Abbreviated Journal
Volume 31 Issue Pages
Keywords 4215 Oceanography: General: Climate and interannual variability; 4207 Oceanography: General: Arctic and Antarctic oceanography; 4522 Oceanography: Physical: El Nino
Abstract Two conflicting views on the causal mechanism of the Antarctic interannual variability often appear in the literature, i.e., whether it is remotely teleconnected to tropical ENSO events or is a self-sustained eastward propagating circumpolar wave generated locally by an ocean-atmosphere coupling mechanism. Using a Fourier decomposition into stationary and propagating components of several oceanic and atmospheric variables, we show that most of the Antarctic interannual variability can be explained by a geographically phase-locked standing wave train linked to tropical ENSO episodes. This ENSO-modulated quasi-stationary variability is not zonally uniform, rather, the strongest ENSO impact is consistently concentrated in the Pacific sector of the Southern Ocean. The eastward propagating wave component is found to be not only minor (25% of variability) but also intermittent in phase, yielding little support for the so-called Antarctic Circumpolar Wave scenario.
Programme 335
Campaign
Address
Corporate Author Thesis
Publisher American Geophysical Union 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 (down) IPEV @ Thierry.Lemaire @ Serial 5624
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Author Pisano,; E. Pisano; Mazzei,; F. Mazzei; Derome,; N. Derome; Ozouf-Costaz,; C. Ozouf-Costaz; Hureau,; J.-C. Hureau; Prisco,; G. Prisco
Title Cytogenetics of the bathydraconid fish Gymnodraco acuticeps (Perciformes, Notothenioidei) from Terra Nova Bay, Ross Sea Type Journal Article
Year 2001 Publication Polar biology Abbreviated Journal Polar Biol.
Volume 24 Issue 11 Pages 846-852
Keywords
Abstract In the framework of the I.C.E.FISH (International Collaborative Effort on Antarctic Fish Adaptive Evolution) project, during the 1998-1999 season at the Italian shore-based Terra Nova Bay Station, the broad fields of adaptation and evolution of the fish suborder Notothenioidei were tackled through the integration of many disciplines. As a representative contribution of I.C.E.FISH, a cytogenetic study of the bathydraconid fish Gymnodraco acuticeps is reported. The Bathydraconidae is a heterogeneous notothenioid taxon whose intra-family relationships are very uncertain. The conventional karyotype and the location of nuclear ribosomal genes, by means of fluorescence in situ hybridisation, contributed to species-specific characterisation and provided the basis for comparative analyses. The karyotype of G. acuticeps consists of 48 chromosomes (2 metacentric, 2 submetacentric and 44 acrocentric); major ribosomal cistrons correspond to a large region in a single chromosome pair. Mapping of the available karyotypic data on a molecular phylogenetic tree provided information on chromosomal diversification during the cladogenesis of the bathydraconids.
Programme 281
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 0722-4060 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5580
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Author Senior, C.; Cerisier, J.-C.; Thorolfsson, A.; Lester, M.
Title Propagation in the ionosphere of convection changes following a sharp interplanetary magnetic field By transition Type Journal Article
Year 2002 Publication Journal of geophysical research-atmospheres Abbreviated Journal J. Geophys. Res.
Volume 107 Issue Pages
Keywords 2463 Ionosphere: Plasma convection; 2740 Magnetospheric Physics: Magnetospheric configuration and dynamics
Abstract The nature of the response of the ionospheric convection to changes in the interplanetary magnetic field (IMF), either quasi-simultaneous over the polar cap and auroral region or propagating with the flow velocity from the noon sector, remains to be understood. We examine the changes in the ionospheric plasma convection associated with a negative to positive transition in the dawn-dusk component (By) of the IMF. A special mode of operation of the SuperDARN HF radars has been used, which provided both a large field of view and high-resolution convection data on three beams. Close to noon, the most characteristic response concerns the position in magnetic local time (MLT) of the merging gap, the ionospheric footprint of the magnetopause reconnection line, which moves longitudinally with a velocity of 1 km/s. In addition, modifications of the convection, which are indirectly related to this motion, are observed. We attribute them to the “quasi-instantaneous” effect related to the incompressibility of the plasma. Far from noon, in the morning sector, the convection reacts with an intermediate delay, which is neither instantaneous nor compatible with the above propagation velocity. A timing of the transition, based on the IMP 8 and Geotail satellites, located on the dawn flank of the magnetosphere and at the nose of the magnetopause, respectively, indicates that the ionospheric perturbation originates at the impact site of the By transition close to 1300 MLT, with a maximum delay of 3 min after it hits the nose of the magnetopause.
Programme 312;911
Campaign
Address
Corporate Author Thesis Bachelor's thesis
Publisher American Geophysical Union Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5623
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Author Park, Y.-H.
Title Determination of the surface geostrophic velocity field from satellite altimetry Type Journal Article
Year 2004 Publication Journal of geophysical research-atmospheres Abbreviated Journal J. Geophys. Res.
Volume 109 Issue Pages
Keywords 4512 Oceanography: Physical: Currents; 4528 Oceanography: Physical: Fronts and jets; 4556 Oceanography: Physical: Sea level variations
Abstract Presently available marine geoid models are not accurate enough to extract the mean surface circulation directly from satellite altimetry. A novel method for estimating the mean velocity field of major ocean current systems is derived from the free surface boundary condition. With a given quasi-geostrophic balance for the horizontal surface flow, a scaling analysis of this boundary condition indicates that although the vertical velocity w is mostly balanced by the local change of the free surface, ???/?t, useful information on the mean current ($\overline{u}$, $\overline{v}$) is contained in a small ageostrophic departure (???/?t ? w). Our method consists in the development of a simple algebraic equation with two unknowns ($\overline{u}$, $\overline{v}$) and an adjustable parameter $\widetilde{\alpha}$ associated with ???/?t, assuming that the latter is proportional to (???/?t ? w). Most interestingly, ???/?t and all other coefficients of the equation can be determined from altimetry. The altimeter data used is combined TOPEX/Poseidon-ERS gridded data, and the solution is obtained by least squares, minimizing the contribution from the time-variable part of the parameter $\widetilde{\alpha}$ and prescribing the zonal direction of the mean current. The method, which is found to be particularly useful for quasi-zonal high-energy current systems, has been validated against direct observations in the Gulf Stream and Southern Ocean. Comparisons with direct observations and Monte Carlo experiments suggest an overall solution error of about 10 cm s?1. Once calibrated against regional velocity statistics, this method will be able to determine from altimetry the mean or instantaneous surface velocity field down to the frontal scale, with a realism that has been inaccessible because of the geoid constraint.
Programme 335
Campaign
Address
Corporate Author Thesis
Publisher American Geophysical Union Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5582
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Author Duval, P.; Montagnat, M.
Title Comment on “Superplastic deformation of ice: Experimental observations” by D. L. Goldsby and D. L. Kohlstedt Type Journal Article
Year 2002 Publication Journal of geophysical research-atmospheres Abbreviated Journal J. Geophys. Res.
Volume 107 Issue Pages
Keywords 1827 Hydrology: Glaciology; 1863 Hydrology: Snow and ice; 3902 Mineral Physics: Creep and deformation; 5120 Physical Properties of Rocks: Plasticity, diffusion, and creep
Abstract
Programme 902
Campaign
Address
Corporate Author Thesis
Publisher American Geophysical Union Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5637
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Author Legrand, M.; Preunkert, S.; Wagenbach, D.; Fischer, H.
Title Seasonally resolved Alpine and Greenland ice core records of anthropogenic HCl emissions over the 20th century Type Journal Article
Year 2002 Publication Journal of geophysical research-atmospheres Abbreviated Journal J. Geophys. Res.
Volume 107 Issue Pages
Keywords 0325 Atmospheric Composition and Structure: Evolution of the atmosphere; 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; 0322 Atmospheric Composition and Structure: Constituent sources and sinks
Abstract The continuous highly resolved records of Cl?, Na+, and Ca2+ in ice cores from Col du Dôme (4250 m elevation, French Alps) and Summit (3240 m elevation, central Greenland) are used to reconstruct the history of atmospheric HCl pollution over Europe and Greenland since the early 20th century. The evaluation of the HCl amount in summer snow deposits at high-elevation Alpine sites is complex since continental emissions (soils, halide evaporites, and possibly manure-fertilized fields) account for 80% of the chloride budget and only one fifth of Cl? is related to HCl. During the preindustrial era the HCl content of summer Alpine snow layers fluctuated between 0 and 6 ng g?1, likely in relation with a highly variable interannual biomass burning activity in western Europe. From 1925 to 1960 the HCl levels were slightly higher (3–9 ng g?1), mainly due to growing coal burning emissions in western Europe. In the late 1960s a sharp increase of HCl levels (up to 17 ng g?1) took place as a result of the setup of waste incineration in western Europe, this process contributing 3–4 times more than coal combustion to the HCl budget of summer Alpine snow layers deposited between 1970 and 1990. In winter, sea spray emissions dominate (?78%) the total Cl? level of Alpine snow layers. The HCl trend in these snow layers remained limited to ?2 ng g?1 over the 20th century, likely in relation to waste incineration after 1965. In Greenland snow layers most of particulate Cl? originates from sea spray, 1/3 to 2/3 of Cl? being present as HCl in spring and summer, respectively. The Greenland HCl ice core records indicate a preindustrial HCl level close to 4 ng g?1, which is found to be mainly due to the sea-salt dechlorination, while the contribution of passive volcanic HCl emissions at high northern latitudes can be neglected. The input from sea-salt dechlorination has been enhanced by a factor of 2–3 during the second half of the 20th century similarly to the increase of the atmospheric acidity in response to growing NOx and SO2 anthropogenic emissions.
Programme 414
Campaign
Address
Corporate Author Thesis
Publisher American Geophysical Union Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number (down) IPEV @ Thierry.Lemaire @ Serial 5629
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