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Yagova, N.V.; Pilipenko, V.A.; Lanzerotti, L.J.; Engebretson, M.J.; Rodger, A.S.; Lepidi, S.; Papitashvili, V.O. (2004). Two-dimensional structure of long-period pulsations at polar latitudes in Antarctica. J. Geophys. Res., 109.
Abstract: Two-dimensional (2-D) statistical distributions of spectral power and coherence of polar geomagnetic variations with quasi-periods about 10 min are analyzed using data from magnetometer arrays in Antarctica. Examination of the 2-D patterns of spectral power and coherence shows the occurrence of significant variations in geomagnetic power levels but with low spatial coherence near the cusp projection and in the auroral region. At the same time, low-amplitude pulsations, which we coin Pi cap
3 pulsations, are very coherent throughout the polar cap. The region occupied by coherent Pi cap
3 pulsations is shifted toward local MLT night from the geomagnetic pole and is decoupled from the regions of auroral and cusp ULF activity. The spectral power varies with time at polar latitudes in a manner different from that at auroral latitudes. Diurnal variations of power at different stations at the same geomagnetic latitude exhibit different behavior depending on the station's position relative to geomagnetic and geographic poles. This asymmetry is shown to be partly attributed to the variations of the ionospheric conductance. The primary source of polar pulsations is probably related to intermittent magnetosheath turbulence and tail lobe oscillations, though a particular propagation mechanism has not as yet been identified.
Keywords: 2776 Magnetospheric Physics: Polar cap phenomena; 2752 Magnetospheric Physics: MHD waves and instabilities; 2744 Magnetospheric Physics: Magnetotail; 2724 Magnetospheric Physics: Magnetopause, cusp, and boundary layers
Programme: 905
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ANGELIER F, MOE B, CLEMENT-CHASTEL C, BECH C, CHASTEL O. (2007). Corticosterone levels in relation to change of mate in Black-legged kittiwakes. Condor, 109, 668–674.
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Delmotte, M.; Chappellaz, J.; Brook, E.; Yiou, P.; Barnola, J.M.; Goujon, C.; Raynaud, D.; Lipenkov, V.I. (2004). Atmospheric methane during the last four glacial-interglacial cycles: Rapid changes and their link with Antarctic temperature. J. Geophys. Res., 109.
Keywords: climate; atmospheric methane; ice core; 0325 Atmospheric Composition and Structure: Evolution of the atmosphere; 1610 Global Change: Atmosphere; 1615 Global Change: Biogeochemical processes; 3339 Meteorology and Atmospheric Dynamics: Ocean/atmosphere interactions
Programme: 439;902
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Legrand, M.; Preunkert, S.; Jourdain, B.; Aumont, B. (2004). Year-round records of gas and particulate formic and acetic acids in the boundary layer at Dumont d'Urville, coastal Antarctica. J. Geophys. Res., 109.
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Alexander, B.; Savarino, J.; Kreutz, K.J.; Thiemens, M.H. (2004). Impact of preindustrial biomass-burning emissions on the oxidation pathways of tropospheric sulfur and nitrogen. J. Geophys. Res., 109.
Abstract: Ice core measurements (H2O2 and CH4/HCHO) and modeling studies indicate a change in the oxidation capacity of the atmosphere since the onset of the Industrial Revolution due to increases in fossil fuel burning emissions [e.g., Lelieveld et al., 2002; Hauglustaine and Brasseur, 2001; Wang and Jacob, 1998; Staffelbach et al., 1991]. The mass-independent fractionation (MIF) in the oxygen isotopes of sulfate and nitrate from a Greenland ice core reveal that biomass-burning events in North America just prior to the Industrial Revolution significantly impacted the oxidation pathways of sulfur and nitrogen species deposited in Greenland ice. This finding highlights the importance of biomass-burning emissions for atmospheric chemistry in preindustrial North America and warrants the inclusion of this impact in modeling studies estimating changes in atmospheric oxidant chemistry since the Industrial Revolution, particularly when using paleo-oxidant data as a reference for model evaluation.
Programme: 1011
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. (2004). New modeling of the Vostok ice flow line and implication for the glaciological chronology of the Vostok ice core. J. Geophys. Res., 109.
Abstract: We have used new spaceborne (elevation) and airborne (ice thickness) data to constrain a 2D1/2 model of snow accumulation and ice flow along the Ridge B-Vostok station ice flow line (East Antarctica). We show that new evaluations of the ice flow line geometry (from the surface elevation), ice thickness (from low-frequency radar data), and basal melting and sliding change significantly the chronology of the Vostok ice core. This new Vostok dating model reconciles orbital and glaciological timescales and is in good agreement with the Dome Fuji glaciological timescale. At the same time, the new model shows significantly older ages than the previous GT4 timescale for the last glacial part, being thus in better agreement with the GRIP and GISP2 chronologies.
Keywords: glaciology; paleoclimatology; Antarctica; inverse theory; 1827 Hydrology: Glaciology; 3344 Meteorology and Atmospheric Dynamics: Paleoclimatology; 3260 Mathematical Geophysics: Inverse theory; 9310 Information Related to Geographic Region: Antarctica
Programme: 355
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Lambert Van Roozendael Simon De Maziere Pommereau Goutail Sarkissian Denis Dorokhov Eriksen Kyro Leveau Roscoe Vaughan Wahlstrom. (1996). Validation of the ERS-2 GOME products with the SAOZ network. (Vol. 108). Bachelor's thesis, , .
Abstract: Proc. Workshop on Gome validation, ESA WWPP
Programme: 209
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Lambert, J.-C. ; Van Roozendael, M. ; Simon, P. C. ; De Maziere, M. ; European Space Agency. (1996). Gome products validation With the SAOZ Network. (Vol. 108). Bachelor's thesis, , .
Abstract: Proc. Workshop on Gome validation, ESA WWPP
Programme: 209
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Pessel M. & Gibert D. (2003). Multiscale electrical impedance tomography. J. Geophys. Res., 108(b1).
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Savarino, J.; Bekki, S.; Cole-Dai, J.; Thiemens, M.H. (2003). Evidence from sulfate mass independent oxygen isotopic compositions of dramatic changes in atmospheric oxidation following massive volcanic eruptions. J. Geophys. Res., 108.
Abstract: Oxygen isotopic ratio measurements (?17O and ?18O) of background and volcanic sulfate preserved in South Pole snow and ice were used to investigate the impact on the oxidation state of the atmosphere by explosive volcanic eruptions. By comparing different paleovolcanic events, we observe a difference in the SO2 oxidation pathway between moderate (tens of teragrams (Tg) of SO2) and massive (hundreds of Tg) eruptions. Both isotopic data and numerical simulations suggest the shutdown of stratospheric OH chemistry and the opening of unaccounted oxidation channels for SO2, such as the reaction with O(3P) atoms when hundreds of Tg of SO2 are injected into the stratosphere. It is very likely that oxidation rates and pathways and concentrations of most traces gases are also dramatically affected, with potentially important implications for climate forcing.
Programme: 457
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