Abstract: Chapter peer-reviewed edited volumes

Abstract: Alors qu’il existe une grande diversité de valeurs attribuées à la nature, les déterminants sociaux habituels, tels que la catégorie socio-professionnelle, l’âge ou le sexe, se sont avérés peu explicatifs. Cet article explore le rôle de la socialisation, et plus particulièrement de la socialisation primaire dans le type de valeur que les individus affectent à la nature. L’enquête s’est déroulée dans les îles subantarctiques, choisies car la nature y est valorisée dans un contexte non-utilitariste et non-marchand, ce qui permet l’expression d’un grand nombre de valeurs. Nous avons analysé les correspondances entre les formes de socialisation des individus à la nature et les valeurs qu’ils lui affectent. La principale distinction met en tension deux instances de socialisation primaire : au sein de la famille et par les groupes de pairs. Les premières conduisent à une évaluation de la nature suivant un principe dominant et abstrait, les secondes à une évaluation égalitaire et concrète. En revanche, ceux qui n’ont pas été socialisés à la nature durant l’enfance ont plutôt tendance à mettre en avant la valorisation d’eux-mêmes acquise par l’expérience de nature. Si les trajectoires linéaires sont largement majoritaires, des renforcements ou des altérations sont possibles, montrant que certaines formes de socialisation secondaire peuvent faire ou évoluer les valeurs attribuées à la nature.

Abstract: Global seismographic networks (GSNs) emerged during the late nineteenth and early twentieth centuries, facilitated by seminal international developments in theory, technology, instrumentation, and data exchange. The mid- to late-twentieth century saw the creation of the World-Wide Standardized Seismographic Network (1961) and International Deployment of Accelerometers (1976), which advanced global geographic coverage as seismometer bandwidth increased greatly allowing for the recording of the Earth's principal seismic spectrum. The modern era of global observations and rapid data access began during the 1980s, and notably included the inception of the GEOSCOPE initiative (1982) and GSN (1988). Through continual improvements, GEOSCOPE and the GSN have realized near-real time recording of ground motion with state-of-art data quality, dynamic range, and timing precision to encompass 180 seismic stations, many in very remote locations. Data from GSNs are increasingly integrated with other geophysical data (e.g., space geodesy, infrasound and Interferometric Synthetic Aperture Radar). Globally distributed seismic data are critical to resolving crust, mantle, and core structure; illuminating features of the plate tectonic and mantle convection system; rapid characterization of earthquakes; identification of potential tsunamis; global nuclear test verification; and provide sensitive proxies for environmental changes. As the global geosciences community continues to advance our understanding of Earth structure and processes controlling elastic wave propagation, GSN infrastructure offers a springboard to realize increasingly multi-instrument geophysical observatories. Here, we review the historical, scientific, and monitoring heritage of GSNs, summarize key discoveries, and discuss future associated opportunities for Earth Science.

Abstract: Indirect ecological interactions such as competition for resources between fisheries and marine predators have often been proposed but can be difficult to demonstrate empirically. The Kerguelen Plateau in the Southern Indian Ocean supports fisheries for both Patagonian toothfish and mackerel icefish and is also an important foraging ground for several avian and mammalian predators, including the southern elephant seal. We quantified the spatio-temporal use of the plateau by southern elephant seals and found that males and females spent 30% of their time on the plateau within the commonly used fishing grounds, indicating the possibility of competition for resources there. We then contrasted the seals’ use of two habitat types, the benthos (where interactions with the long-line fisheries are most likely) and the epi-pelagic zone. The likelihood of feeding on the benthos declined as ocean depth increased and was also less likely at night. Males were also more likely to feed on the benthos than females. The sub-adult male seals consumed an estimated 6,814 – 14,848 tons of high energy content prey (including toothfish) and females 7,085 – 18,037 tons from the plateau during the post-molt winter months. For males this represented 79.6 – 173.4% of the mean annual catch by the Kerguelen fishery compared to 82.8 – 210.7% for adult females. When considering the seals consumption of fish from the benthos within the fishing grounds these estimates decreased to 3.6 – 15.1% of the fishery’s total annual catch for females and 7.8 – 19.1% for males. While this further indicates the possibility of indirect ecological interactions (with the fishery taking more fish than the seals), the lack of detailed diet information for the seals precludes us from establishing the degree or nature of the possible interactions because the importance of toothfish and icefish in the diet of the seals is unknown. However, the unique life history and highly polygynous nature of this species, and the lack of evidence of a measurable effect on either the seal’s population growth rates or the catch per unit of the fishery, suggest that any indirect ecological interactions are not of sufficient magnitude to affect either the seal population or the fishery.

Abstract: To mitigate temporal aliasing effects in monthly mean global gravity fields from the GRACE and GRACE-FO satellite tandem missions, both tidal and non-tidal background models describing high-frequency mass variability in atmosphere and oceans are needed. To quantify tides in the atmosphere, we exploit the higher spatial (31 km) and temporal (1 hr) resolution provided by the latest atmospheric ECMWF reanalysis, ERA5. The oceanic response to atmospheric tides is subsequently modeled with the general ocean circulation model MPIOM (in a recently revised TP10L40 configuration that includes the feedback of self-attraction and loading to the momentum equations and has an improved bathymetry around Antarctica) as well as the shallow water model TiME (employing a much higher spatial resolution and more elaborate tidal dissipation than MPIOM). Both ocean models consider jointly the effects of atmospheric pressure variations and surface wind stress. We present the characteristics of 16 waves beating at frequencies in the 1–6 cpd band and find that TiME typically outperforms the corresponding results from MPIOM and also FES2014b as measured from comparisons with tide gauge data. Moreover, we note improvements in GRACE-FO laser ranging interferometer range-acceleration pre-fit residuals when employing the ocean tide solutions from TiME, in particular, for the S1 spectral line with most notable improvements around Australia, India, and the northern part of South America.