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Tuck G.N., Polacheck T., Croxall J.P., Weimerskirch H., Prince P.A. & Wotherspoon S. (1999). The potential of archival tag to provide long-term movement and behaviour data for seabirds:first results from Wandering albatrossDiomedea exulans of South Georgia and Crozet Islands. Emu, 99, 60–68.
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Tuck G.N., Polacheck T., Croxall J.P. & Weimerskirch H. (2001). Modelling the impact of fishery by-catches on albatross populations. J Appl Ecol, 38, 1182–1196.
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Tsuruta, A., T. Aalto, L. Backman, J. Hakkarainen, I.T. van der Laan-Luijkx, M.C. Krol, R. Spahni, S. Houweling, M. Laine, M. van der Schoot, R. Langenfelds, R. Ellul, and W. Peters, Development of CarbonTracker Europe-CH4 – Part 1: system set-up and sensitivity analyses, Geosci. Model Dev. Discuss., 2016a. (2016). Development of CarbonTracker Europe-CH4 – Part 1: system set-up and sensitivity analyses. Geoscientific Model Development Discussions, .
Abstract: CarbonTracker Europe-CH4 (CTE-CH4) inverse model versions 1.0 and 1.1 are presented. The model optimizes global surface methane emissions from biosphere and anthropogenic sources using an ensemble Kalman filter (EnKF) based optimization method, using the TM5 chemistry transport model as an observation operator, and assimilating global in-situ atmospheric methane mole fraction observations. In this study, we examine sensitivity of our CH4 emission estimates on the ensemble size, covariance matrix, prior estimates, observations to be assimilated, assimilation window length, convection scheme in TM5, and model structure in the emission estimates by performing CTE-CH4 with several set-ups. The analyses show that the model is sensitive to most of the parameters and inputs that were examined. Firstly, using a large enough ensemble size stabilises the results. Secondly, using an informative covariance matrix reduces uncertainty estimates. Thirdly, agreement with discrete observations became better when assimilating continuous observations. Finally, the posterior emissions were found sensitive to the choice of prior estimates, convection scheme and model structure, particularly to their spatial distribution. The distribution of posterior mole fractions derived from posterior emissions is consistent with the observations to the extent prescribed in the various covariance estimates, indicating a satisfactory performance of our system. Academic paper: Development of CarbonTracker Europe-CH4 – Part 1: system set-up and sensitivity analyses. Available from: https://www.researchgate.net/publication/306338110DevelopmentofCarbonTrackerEurope-CH4-Part1systemset-upandsensitivityanalyses [accessed Apr 4, 2017].
Programme: 416
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Tsuruta, A., T. Aalto, L. Backman, J. Hakkarainen, I.T. van der Laan-Luijkx, M.C. Krol, R. Spahni, S. Houweling, M. Laine, E. Dlugokencky, A.J. Gomez-Pelaez, M. van der Schoot, R. Langenfelds, R. Ellul, A. J., F. Apadula, C. Gerbig, D.G. Feist, R. Kivi, Y. Yoshida, and W. Peters. (2016). Development of CarbonTracker Europe-CH4 – Part 2: global methane emission estimates and their evaluation for 2000–2012. Geoscientific model development discussions, .
Abstract: Gobal methane emissions were estimated for 2000–2012 using the CarbonTracker Europe-CH4 (CTE-CH4) data assimilation system. In CTE-CH4, the anthropogenic and biosphere emissions of CH4 are simultaneously constrained by global atmospheric in-situ methane mole fraction observations. We use three configurations developed in Tsuruta et al. (2016) to assess the sensitivity of the CH4 flux estimates to (a) the number of unknown flux scaling factors to be optimized which in turn depends on the choice of underlying land-ecosystem map, and (b) on the parametrization of vertical mixing in the 30 atmospheric transport model TM5. The posterior emission estimates were evaluated by comparing simulations to surface in-situ observation sites, to profile observations made by aircraft, to dry air total column-averaged mole fractions (XCH4) observations from the Total Carbon Column Observing Network (TCCON), and to XCH4 retrievals from the Greenhouse gases Observing SATellite (GOSAT). Our estimated posterior mean global total emissions during 2000–2012 are 516 $\pm$ 51 Tg CH4 yr\textminus1, and emission estimates during 2007–2012 are 18 Tg CH4 yr\textminus1 greater than those from 2001–2006, mainly driven by an 35 increase in emissions from the south America temperate region, the Asia temperate region and Asia tropics. The sensitivity of the flux estimates to the underlying ecosystem map was large for the Asia temperate region and Australia, but not significant in the northern latitude regions, i.e. the north American boreal region, the north American temperate region and Europe. Instead, the posterior estimates for the northern latitude regions show larger sensitivity to the choice of convection scheme in TM5. The Gregory et al. (2000) mixing scheme with faster interhemispheric exchange leads to higher estimated CH4 emissions at northern latitudes, and lower emissions in southern latitudes, compared to the estimates using Tiedtke (1989) convection scheme. Our evaluation with non-assimilated observations showed that posterior mole fractions were better matched with the 5 observations when Gregory et al. (2000) convection scheme was used.
Programme: 416
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Tshoanelo Miya, Ofer Gon, Monica Mwale, Elie Poulin. (2016). Molecular systematics and taxonomic status of three latitudinally widespread nototheniid (Perciformes: Notothenioidei) fishes from the Southern Ocean (Vol. 4061).
Abstract: The taxonomic status of the three nototheniids, Lepidonotothen squamifrons, L. larseni and Gobionotothen marionensis from different localities in the Southern Ocean is re-evaluated at the DNA level. DNA sequence divergences and phylogenetic relationship were estimated using a combined mitochondrial (mtDNA, ND2 and COI) dataset and data for one nuclear gene (S7 intron 1). Phylogenies of both datasets had Lepidonotothen kempi nested within L. squamifrons lineage, with low sequence divergences (0% to 0.4%) between the two nominal species suggesting that they are populations of one species. Therefore, these results do not support the previous splitting of L. squamifrons into different species. Similarly, the L. larseni specimens also represented a single genetic unit (0.3% to 0.6%) with low geographic variation between Atlantic and Indian Ocean specimens, which does not support the splitting of this species into geographically restricted species. The mtDNA phylogeny clearly separated individuals of G. acuta from Kerguelen, Heard and MacDonald Islands from G. marionensis individuals into different clades, with sequence divergence of 2.9% between these clades supporting they are different species.
Keywords: Atlantic Ocean sector Gobionotothen Indian Ocean sector Lepidonotothen mitochondrial DNA nuclear gene Pisces sequence divergence
Programme: 1044
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Trucchi Emiliano, Gratton Paolo, Whittington Jason D, Cristofari Robin, Le Maho Yvon, Stenseth Nils Chr, Le Bohec Céline, . (2014). King penguin demography since the last glaciation inferred from genome-wide data
. Proceedings of the Royal Society of London B: Biological Sciences, 281(1787), 20140528.
Abstract: How natural climate cycles, such as past glacial/interglacial patterns, have shaped species distributions at the high-latitude regions of the Southern Hemisphere is still largely unclear. Here, we show how the post-glacial warming following the Last Glacial Maximum (ca 18 000 years ago), allowed the (re)colonization of the fragmented sub-Antarctic habitat by an upper-level marine predator, the king penguin Aptenodytes patagonicus. Using restriction site-associated DNA sequencing and standard mitochondrial data, we tested the behaviour of subsets of anonymous nuclear loci in inferring past demography through coalescent-based and allele frequency spectrum analyses. Our results show that the king penguin population breeding on Crozet archipelago steeply increased in size, closely following the Holocene warming recorded in the Epica Dome C ice core. The following population growth can be explained by a threshold model in which the ecological requirements of this species (year-round ice-free habitat for breeding and access to a major source of food such as the Antarctic Polar Front) were met on Crozet soon after the Pleistocene/Holocene climatic transition.
Programme: 137
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Trouvilliez, A., C. Genthon, F. Naaim-Bouvet, L. Piard, H. Bellot, C. Amory, V. Vionnet, H. Gallée, J. Guyomarc'h. (2014). Lands of blizzard.
Abstract: 7th International Conference on the Global Water and Energy Cycle, La Haye, NL, 14-17 Juillet 2014.
Programme: 1013
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Trouvilliez, A., C. Amory, C. genthon, L. Piard, F. Naaim, H. Bellot, H. Gallée. (2014). Blowing snow in Antarctica, 3 years of continuous observations in Adélie Land.
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Trouvilliez Alexandre, Naaim-Bouvet Florence, Genthon Christophe, Piard Luc, Favier Vincent, Bellot Hervé, Agosta Cécile, Palerme Cyril, Amory Charles, Gallée Hubert, . (2014). A novel experimental study of aeolian snow transport in Adelie Land (Antarctica)
. Cold Regions Science and Technology, 108, 125–138.
Abstract: None of the previous aeolian snow transport campaigns in Antarctica meet the requirements in terms of temporal resolution, long-term series and qualified instruments for evaluations of meteorological and climate models including parameterization for aeolian snow transport. Consequently, determining the quantity of snow transported remains a challenge. A field campaign was therefore launched in January 2009, in Adélie Land, Antarctica, to acquire new model-evaluation-oriented observations within the European ICE2SEA project, with the logistical support of the French polar Institute (IPEV). The available aeolian snow transport sensors are reviewed and the sensor that best suited our specific needs was chosen: FlowCapt™ acoustic sensors. Three automatic weather stations were deployed with FlowCapts™ close to the coast. The stations' locations are distinct, ranging from 1 to 100km inland, one of them with a 7-m mast with six levels of anemometers and thermohygrometers. The fluid and impact threshold friction velocities recorded were 0.48±0.09ms−1 and 0.4±0.09ms−1, respectively, with a high standard deviation of 0.12±0.03ms−1 and 0.13±0.03ms−1, respectively. The aeolian snow transport frequency in Adélie Land was very high with seasonal variation of transport occurring with minima during the austral summer. Seven percent of the aeolian snow transport events were drifting snow (maximum particle's height, <1m above the surface). The snow quantity transported was above 1kiloton per year in the first meter above the surface.
Keywords: Aeolian transport, Antarctica, Blowing snow, Drifting snow,
Programme: 411,1013
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Trouvilliez A., F. Naiim, H. Gallée, C. Genthon, V. Favier, H. bellot. (2013). New observation of blowing snow in Adélie Land, east Antarctic plateau.
Abstract: DACA 2013, 8-12 Juillet 2013, Davos, Suisse.
Programme: 1013
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