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Whinam, J.; Copson, G.; Chapuis, J.-L. (2006). Subantarctic Terrestrial Conservation and Management.
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Whinam J., Copson G. & Chapuis J.L. (2006). Subantarctic terrestrial conservation and management..
Abstract: In: Bergstrom DM, Convey P & Huiskes AHL (eds), Trends in Antarctic Terrestrial and Limnetic Ecosystems: Antarctica as a global indicator. Springer, Dordrecht, The Netherlands
Programme: 136
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Wheeler R. & Alix C. (2004). Economical and Cultural Significance of driftwood in Coastal Communities of Southwest Alaska. Report to Cooperative Extension Services..
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Wenjie Lei, Youyi Ruan, Ebru Bozdağ, Daniel Peter, Matthieu Lefebvre, Dimitri Komatitsch, Jeroen Tromp, Judith Hill, Norbert Podhorszki, David Pugmire. (2020). Global adjoint tomography—model GLAD-M25 (Vol. 223).
Abstract: Building on global adjoint tomography model GLAD-M15, we present transversely isotropic global model GLAD-M25, which is the result of 10 quasi-Newton tomographic iterations with an earthquake database consisting of 1480 events in the magnitude range 5.5 ≤ Mw ≤ 7.2, an almost sixfold increase over the first-generation model. We calculated fully 3-D synthetic seismograms with a shortest period of 17 s based on a GPU-accelerated spectral-element wave propagation solver which accommodates effects due to 3-D anelastic crust and mantle structure, topography and bathymetry, the ocean load, ellipticity, rotation and self-gravitation. We used an adjoint-state method to calculate Fréchet derivatives in 3-D anelastic Earth models facilitated by a parsimonious storage algorithm. The simulations were performed on the Cray XK7 ‘Titan’ and the IBM Power 9 ‘Summit’ at the Oak Ridge Leadership Computing Facility. We quantitatively evaluated GLAD-M25 by assessing misfit reductions and traveltime anomaly histograms in 12 measurement categories. We performed similar assessments for a held-out data set consisting of 360 earthquakes, with results comparable to the actual inversion. We highlight the new model for a variety of plumes and subduction zones.
Programme: 133
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Wendler G., Andre J.C., Pettre P., Gosink J. & Parish T. (1993). Katabatic winds in Adélie Coast. Antarctic research series, , 23–46.
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Weller Rolf, Wagenbach Dietmar, Legrand Michel, Elsässer Christoph, Tian-kunze Xiangshan, König-langlo Gert,. (2011). Continuous 25-yr aerosol records at coastal Antarctica I: inter-annual variability of ionic compounds and links to climate indices. Tellus B, .
Abstract: The aerosol climatology at the coastal Antarctic Neumayer Station (NM) was investigated based on continuous, 25-yr long observations of biogenic sulphur components (methanesulfonate and nonsea salt sulphate), sea salt and nitrate. Although significant long-term trends could only be detected for nitrate (3.6 ± 2.5% per year between 1983 and 1993 and +4.0 ± 3.2% per year from 19932007), non-harmonic periodicities between 2 and 5 yr were typical for all species. Dedicated time series analyses revealed that relations to sea ice extent and various circulation indices are weak at best or not significant. In particular, no consistent link between sea ice extent and sea salt loadings was evident suggesting only a rather local relevance of the NM sea salt record. Nevertheless, a higher Southern Annular Mode index tended to entail a lower biogenic sulphur signal. In examining the spatial uniformity of the NM findings we contrasted them to respective 17 yr records from the coastal Dumont dUrville Station. We found similar long-term trends for nitrate, indicating an Antarctic-wide but not identifiable atmospheric signal, although any significant impact of solar activity or pollution could be ruled out. No inter-site variability on the multiannual scale was evident for the other ionic compounds.
Programme: 414
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Welker, J., Harding, A.M.A., Karnovsky, N.J., Steen, H., Strom, H. & Gabrielsen, G.W. (2009). Flexibility in the bimodal foraging strategy of a high Arctic alcid, the little auk Alle alle. J. Avian Biol., 40, 388–399.
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WELCKER, J., STEEN, H., HARDING, A.M.A. & GABRIELSEN, G.W. (2009). Sex-specific provisioning behaviour in a monomorphic seabird with a bimodal foraging strategy. Ibis (Lond. 1859), 141, 502–513.
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Welcker Jorg, Harding Ann M A, Kitaysky Alexander S, Speakman John R, . (2009). Daily energy expenditure increases in response to low nutritional stress in an Arctic-breeding seabird with no effect on mortality
. Functional Ecology, 23(6), 1081–1090.
Abstract: 1. The regulation of energy expenditure in relation to food availability and its consequences for individual fitness in free-ranging animals are poorly understood. Increased daily energy expenditure (DEE) may be viewed as the result of two different processes: expenditure may be forced
Programme: 388
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Welcker Jorg, Chastel Olivier, Gabrielsen Geir W, Guillaumin Jerome, Kitaysky Alexander S, Speakman John R, Tremblay Yann, Bech Claus, . (2013). Thyroid Hormones Correlate with Basal Metabolic Rate but Not Field Metabolic Rate in a Wild Bird Species
. PLOS ONE, 8(2).
Abstract: Thyroid hormones (TH) are known to stimulate in vitro oxygen consumption of tissues in mammals and birds. Hence, in many laboratory studies a positive relationship between TH concentrations and basal metabolic rate (BMR) has been demonstrated whereas evidence from species in the wild is scarce. Even though basal and field metabolic rates (FMR) are often thought to be intrinsically linked it is still unknown whether a relationship between TH and FMR exists. Here we determine the relationship between the primary thyroid hormone triiodothyronine (T3) with both BMR and FMR in a wild bird species, the black-legged kittiwake (Rissa tridactyla). As predicted we found a strong and positive relationship between plasma concentrations of T3 and both BMR and mass-independent BMR with coefficients of determination ranging from 0.36 to 0.60. In contrast there was no association of T3 levels with either whole-body or mass-independent FMR (R2 = 0.06 and 0.02, respectively). In accordance with in vitro studies our data suggests that TH play an important role in modulating BMR and may serve as a proxy for basal metabolism in wild birds. However, the lack of a relationship between TH and FMR indicates that levels of physical activity in kittiwakes are largely independent of TH concentrations and support recent studies that cast doubt on a direct linkage between BMR and FMR.
Programme: 330
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