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Charrassin, J.B., Hindell, M., Rintoul, S.R., Roquet, F., Sokolov,S., Biuw, M., Costa D., Boehme, L.,Lovell, P., Coleman R., Timmerman, R., Meijers A., Meredith M., Park Y.H., Bailleul F., Tremblay Y., Bost C.A., McMahon C.R., Field I.C., Fedak M.A. , Guinet C. (2008). Southern Ocean frontal structure and sea ice formation rates revealed by elephant seals. Proc. Natl. Acad. Sci. U.S.A., 105, 11634–11639.
Abstract: Polar regions are particularly sensitive to climate change, with the potential for significant feedbacks between ocean circulation, sea ice, and the ocean carbon cycle. However, the difficulty in obtaining in situ data means that our ability to detect and interpret change is very limited, especially in the Southern Ocean, where the ocean beneath the sea ice remains almost entirely unobserved and the rate of sea-ice formation is poorly known. Here, we show that southern elephant seals (Mirounga leonina) equipped with oceanographic sensors can measure ocean structure and water mass changes in regions and seasons rarely observed with traditional oceanographic platforms. In particular, seals provided a 30-fold increase in hydrographic profiles from the sea-ice zone, allowing the major fronts to be mapped south of 60°S and sea-ice formation rates to be inferred from changes in upper ocean salinity. Sea-ice production rates peaked in early winter (April–May) during the rapid northward expansion of the pack ice and declined by a factor of 2 to 3 between May and August, in agreement with a three-dimensional coupled ocean–sea-ice model. By measuring the high-latitude ocean during winter, elephant seals fill a “blind spot” in our sampling coverage, enabling the establishment of a truly global ocean-observing system.
Programme: 109;394;452
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Nevitt G.A., Losekoot M. & Weimerskirch H. (2008). Evidence for olfactory search in Wandering albatross, Diomedea exulans. Proc. Natl. Acad. Sci. U.S.A., 105, 4576–4581.
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Barbraud, C., Weimerskirch, H., Bost, C.A., Forcada, J., Trathan, P., Ainley, D. (2008). Are king penguin populations threatened by Southern Ocean warming? Proc. Natl. Acad. Sci. U.S.A., 105(26), E38.
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White, J. F., Wagner, R. H., Helfenstein, F., Hatch, S. A., Mulard, H., Naves, L. C. and Danchin, E. (2008). Multiple deleterious effects of experimentally aged sperm in a monogamous bird. Proc. Natl. Acad. Sci. U.S.A., 105, 13947–13952.
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Karlöf, L.; Winther, J.-G.; Isaksson, E.; Kohler, J.; Pinglot, J.F.; Wilhelms, F.; Hansson, M.; Holmlund, P.; Nyman, M.; Pettersson, R.; Stenberg, M.; Thomassen, M.P.A.; van der Veen, C.; van de Wal, R.S.W. (1999). A 1500 year record of accumulation at Amundsenisen western Dronning Maud Land, Antarctica, derived from electrical and radioactive measurements on a 120 m ice core. J. Geophys. Res., 105.
Abstract: During the Nordic EPICA pre-site survey in Dronning Maud Land in 1997/1998 a 120 m long ice core was retrieved (76°00'S 08°03'W, 2400 m above sea level). The whole core has been measured using the electric conductivity measurement (ECM) and dielectric profiling (DEP) techniques, and the core chronology has been established by detecting major volcanic eruptions. In a nearby shallow core radioactive traces from nuclear tests conducted during the 1950s and 1960s have been identified. Altogether, 13 ECM and DEP peaks in the long core are identified as originating from specific volcanic eruptions. In addition two peaks of increased total ? activity are identified in the short core. Accumulation is calculated as averages over the time periods between these dated events. Accumulation rate is 62 millimetres (w. eq./yr) for the last 181 years (1816 A.D. to present) and 61 mm w. eq./yr for the last 1457 years (540 A.D. to present). Our record shows an 8% decrease in accumulation between 1452 and 1641 A.D. (i.e. part of the Little Ice Age), compared to the long-term mean.
Programme: 265
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Sciare, J.; Baboukas, E.; Kanakidou, M.; Krischke, U.; Belviso, S.; Bardouki, H.; Mihalopoulos, N. (2000). Spatial and temporal variability of atmospheric sulfur-containing gases and particles during the Albatross campaign. J. Geophys. Res., 105.
Abstract: To investigate the oxidation chemistry of dimethylsulfide (DMS) in the marine atmosphere, atmospheric DMS, SO2, as well as several DMS oxidation products in aerosol phase such as non-sea-salt sulfate (nss-SO4), methanesulfonate (MSA), and dimethylsulfoxide (DMSOp) have been measured during the Albatross campaign in the Atlantic Ocean from October 9 to November 2, 1996. Long-range transport, local sea-to-air flux of DMS (F DMS), marine boundary layer (MBL) height variation, and photochemistry were found to be the major factors controlling atmospheric DMS concentration which ranged from 29 to 396 parts per trillion by volume (pptv) (mean of 120±68 pptv) over the cruise. The spatial variability of MSA and DMSOp follows the latitudinal variations of F DMS. A 2-day period of intensive photochemistry associated with quite stable atmospheric conditions south of the equator allowed the observation of anticorrelated diurnal variations between DMS and its main oxidation products. A chemical box model describing sulfur chemistry in the marine atmosphere was used to reproduce these variations and investigate coherence of experimentally calculated fluxes F DMS with observed DMS atmospheric concentrations. The model results reveal that the measured OH levels are not sufficient to explain the observed DMS daytime variation. Oxidizing species other than OH, probably BrO, must be involved in the oxidation of DMS to reproduce the observed data.
Programme: 344
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Bousquet, P.; Ciais, P.; Peylin, P.; Ramonet, M.; Monfray, P. (1999). Inverse modeling of annual atmospheric CO2 sources and sinks 1. Method and control inversion. J. Geophys. Res., 104(d21), 26,161–26,178.
Abstract: A primary goal of developing the CO2 atmospheric measurement network is to better characterize the sources and sinks of atmospheric CO2. Atmospheric transport models can be used to interpret atmospheric measurements in terms of surface fluxes using inverse methodology. In this paper we present a three-dimensional (3-D) inversion of CO2 measurements in order to infer annual sources and sinks of CO2 at a continental scale (continents and ocean basins) for a climatological year representing the 1985–1995 period. Solving this inverse problem requires (1) a data space representing monthly CO2 measurements, here at 77 sites (surface, ships, planes), (2) a flux space describing a priori fluxes between carbon reservoirs, and (3) a 3-D transport model linking the flux space to the data space. Knowledge of these three elements, together with their associated errors, allows one to reduce the uncertainties of the CO2 sources and sinks. In the 1985–1995 period, for our control inversion, the global continental sink is found to be 2.7±1.5 Gt C yr1 for an optimized deforestation source of 1.4±0.6 Gt C yr1, yielding a net land uptake of 1.3±1.6 Gt C yr1 (fossil fuel removed). The continental partition of this budget is (in units of Gt C yr1): Arctic +0.2±0.3, North America ?0.5±0.6, Europe ?0.3±0.8, north Asia ?1.5±0.7, tropics (except Asia) +0.3±0.9, tropical Asia +0.8±0.4, and Southern Hemisphere ?0.1±0.3. The inferred partition for the controversial Northern Hemisphere CO2 sink reveals that a major sink is located over the north Asia continent. For oceans we find a net global sink of 1.5±0.5 Gt C yr1 with the following partition (in units of Gt C yr1): North Pacific ?0.3±0.2, North Atlantic ?0.8±0.3, equator +0.6±0.2, 20°S–50°S oceans ?0.9±0.3, and austral ocean ?0.1±0.1.
Programme: 146;344
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Malaize B., Paillard D., Jouzel J. & Raynaud D. (1999). The Dole effect over the last two glacial-interglacial cycles. J. Geophys. Res., 104(d12), 14199–14208.
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Greenwald R., Ruohoniemi J.M., Baker K.B., Britow W.A., Sofko G.J., Villain J.P., Lester M. & Slavin J. (1999). Convective response to a transient increase in dayside reconnection. J. Geophys. Res., 104(a5), 10007–10015.
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Maurette M., Engrand C. & Kurat G. (1996). Collection and Microanalysis of Antarctic Micrometeorites. (Vol. 104).
Abstract: Physics. Chemistry, and Dynamics of Interplanetary Dust, ASP Conference Series
Programme: 226
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