Zorn, S.R.; Drewnick, F.; Schott, M.; Hoffmann, T.; Borrmann, S. (2008). Characterization of the South Atlantic marine boundary layer aerosol using an aerodyne aerosol mass spectrometer. Atmospheric chemistry and physics, 8(16), 4711–4728.
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Morin, S.; Marion, G.M.; von Glasow, R.; Voisin, D.; Bouchez, J.; Savarino, J. (2008). Precipitation of salts in freezing seawater and ozone depletion events: a status report. Atmospheric chemistry and physics, 8(23), 7317–7324.
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. (2011). Polarisation in the auroral red line during coordinated EISCAT Svalbard Radar/optical experiments. ANGEO, 29(6), 1101–1112.
Abstract: The polarisation of the atomic oxygen red line in the Earth's thermosphere is observed in different configurations with respect to the magnetic field line at high latitude during several coordinated Incoherent Scatter radar/optical experiment campaigns. When pointing northward with a line-of-sight nearly perpendicular to the magnetic field, we show that, as expected, the polarisation is due to precipitated electrons with characteristic energies of a few hundreds of electron Volts. When pointing toward the zenith or southward with a line-of-sight more parallel to the magnetic field, we show that the polarisation practically disappears. This confirms experimentally the predictions deduced from the recent discovery of the red line polarisation. We show that the polarisation direction is parallel to the magnetic field line during geomagnetic activity intensification and that these results are in agreement with theoretical work.
Programme: 1026
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Gallet J-C, Domine F, Arnaud L, Picard G, Savarino J,. (2011). Vertical profile of the specific surface area and density of the snow at Dome C and on a transect to Dumont D'Urville, Antarctica – albedo calculations and comparison to remote sensing products (Vol. 5). Bachelor's thesis, Copernicus Publications, .
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Frey M M, Savarino J, Morin S, Erbland J, Martins J M F, . (2009). Photolysis imprint in the nitrate stable isotope signal in snow and atmosphere of East Antarctica and implications for reactive nitrogen cycling
. Atmos. Chem. Phys., 9(22), 8681–8696.
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. (2009). What can we learn from HF signal scattered from a discrete arc?
. Ann. Geophys., 27(5), 1887–1896.
Abstract: We present observations of a discrete southward propagating arc which appeared in the mid-night sector at latitudes equatorward of main substorm activity. The arc observations were made simultaneously by the ALFA (Auroral Light Fine Analysis) optical camera, the SuperDARN-CUTLASS HF radar and the Demeter satellite during a coordinated multi-instrumental campaign conducted at the KEOPS/ESRANGE site in December 2006. The SuperDARN HF signal which is often lost in the regions of strong electron precipitation yields in our case clear backscatter from an isolated arc of weak intensity. Consequently we are able to study arc dynamics, the formation of meso-scale irregularities of the electron density along the arc, compare the arc motion with the convection of surrounding plasma and discuss the contribution of ionospheric ions in the arc erosion and its propagation.
Programme: 312;911
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Feng W, Chipperfield M P, Dhomse S, Monge-Sanz B M, Yang X, Zhang K, Ramonet M, . (2010). Evaluation of cloud convection and tracer transport in a three-dimensional chemical transport model
. Atmos. Chem. Phys. Discuss., 10(10), 22953–22991.
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Capron E, Landais A, Chappellaz J, Schilt A, Buiron D, Dahl-Jensen D, Johnsen S J, Jouzel J, Lemieux-Dudon B, Loulergue L, Leuenberger M, Masson-Delmotte V, Meyer H, Oerter H, Stenni B, . (2010). Millennial and sub-millennial scale climatic variations recorded in polar ice cores over the last glacial period
. Clim. Past, 6(3), 345–365.
Abstract: Since its discovery in Greenland ice cores, the millennial scale climatic variability of the last glacial period has been increasingly documented at all latitudes with studies focusing mainly on Marine Isotopic Stage 3 (MIS 3; 28-60 thousand of years before present, hereafter ka) and characterized by short Dansgaard-Oeschger (DO) events. Recent and new results obtained on the EPICA and NorthGRIP ice cores now precisely describe the rapid variations of Antarctic and Greenland temperature during MIS 5 (73.5-123 ka), a time period corresponding to relatively high sea level. The results display a succession of abrupt events associated with long Greenland InterStadial phases (GIS) enabling us to highlight a sub-millennial scale climatic variability depicted by (i) short-lived and abrupt warming events preceding some GIS (precursor-type events) and (ii) abrupt warming events at the end of some GIS (rebound-type events). The occurrence of these sub-millennial scale events is suggested to be driven by the insolation at high northern latitudes together with the internal forcing of ice sheets. Thanks to a recent NorthGRIP-EPICA Dronning Maud Land (EDML) common timescale over MIS 5, the bipolar sequence of climatic events can be established at millennial to sub-millennial timescale. This shows that for extraordinary long stadial durations the accompanying Antarctic warming amplitude cannot be described by a simple linear relationship between the two as expected from the bipolar seesaw concept. We also show that when ice sheets are extensive, Antarctica does not necessarily warm during the whole GS as the thermal bipolar seesaw model would predict, questioning the Greenland ice core temperature records as a proxy for AMOC changes throughout the glacial period.
Programme: 458
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. (2010). Estimation of Antarctic ozone loss from ground-based total column measurements
. Atmos. Chem. Phys., 10(14), 6569–6581.
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. (2010). Accelerating growth of HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane) in the atmosphere
. Atmos. Chem. Phys., 10(13), 5903–5910.
Abstract: We report the first measurements of 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), a substitute for ozone depleting compounds, in air samples originating from remote regions of the atmosphere and present evidence for its accelerating growth. Observed mixing ratios ranged from below 0.01 ppt in deep firn air to 0.59 ppt in the current northern mid-latitudinal upper troposphere. Firn air samples collected in Greenland were used to reconstruct a history of atmospheric abundance. Year-on-year increases were deduced, with acceleration in the growth rate from 0.029 ppt per year in 2000 to 0.056 ppt per year in 2007. Upper tropospheric air samples provide evidence for a continuing growth until late 2009. Furthermore we calculated a stratospheric lifetime of 370 years from measurements of air samples collected on board high altitude aircraft and balloons. Emission estimates were determined from the reconstructed atmospheric trend and suggest that current “bottom-up” estimates of global emissions for 2005 are too high by a factor of three.
Programme: 458
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