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	Author	J. Serafini, J.-P. Barriot, L. Sichoix
	Title	The evolution of precipitable water and precipitation over the Island of Tahiti from hourly to seasonal periods			Type	Journal
	Year	2014	Publication	International Journal of Remote Sensing	Abbreviated Journal
	Volume	35	Issue	18	Pages	6687-6707
	Keywords
	Abstract	The Island of Tahiti (French Polynesia) has a complex meteorological context governed by the South Pacific convergence zone on a large scale and the topography of a high volcanic island on the orographic scale. The island is subject to heavy rainfall (up to 8000 mm year–1 in some areas), mainly during the rainy season (November to April), generating significant geo-morphological changes and property damage each year. To better understand the underlying complex mechanisms leading to precipitation over a broad range of timescales (from hourly to seasonal), we have analysed eight years of data (2001–2008) coming from five sources: a radiometer, radiosoundings, a GPS, Era-Interim reanalysis, and two rain gauges, all located close to or inside the Matatia valley, a small typical Tahitian valley. In particular, we have decomposed the precipitable water distribution into two statistical distributions corresponding to the dry and wet seasons. The time evolution of precipitable water in the dry season is characterized by a log-normal distribution, while the precipitable water time evolution in the wet season is characterized by a reverse log-normal distribution. The bimodality of the probability distributions describing the dynamical processes involved in the Tahiti climate is confirmed by the study of the diurnal evolution in absolute humidity, precipitable water, and precipitation.
	Programme	688
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0143-1161	ISBN	0143-1161	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7079
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	Author	Evgeny A. Pakhomov, Natasha Henschke, Brian P. V. Hunt, Gabriele Stowasser, Yves Cherel
	Title	Utility of salps as a baseline proxy for food web studies			Type	Journal
	Year	2019	Publication	Journal of Plankton Research	Abbreviated Journal
	Volume	41	Issue	1	Pages	3-11
	Keywords
	Abstract	Abstract. IIn recent years, pelagic tunicates (mostly salps, but potentially doliolids, appendicularians and pyrosomes as well) have been used in isotopic studies as a baseline consumer (trophic position 2) when recreating food web dynamics to overcome the challenges of using particulate organic matter (POM). While pelagic tunicates are continuous filter feeders, recent evidence has shown that they have selective feeding behaviors, and preferentially assimilate certain particles. In this review, we combine available stable isotope data for POM and pelagic tunicates and identify that trophic enrichment in 13C and 15N relative to POM is highly variable, and suggests tunicates prefer to consume smaller, heterotrophic organisms. Here we propose that it is not appropriate to consider pelagic tunicates as representative first level consumers in the classical pelagic food web in stable isotope analyses. Rather it needs acknowledgment that they are members of the microbial food web, and thus reflect an alternate food chain.
	Programme	109
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	Corporate Author				Thesis	Bachelor's thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0142-7873	ISBN	0142-7873	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7517
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	Author	Liubomira Romanova, Charles Stépanoff, Norbert Telmon, Eric Crubézy
	Title	Health access inequities and magic medicine: the first ancient evidence?			Type	Journal
	Year	2020	Publication	The Lancet	Abbreviated Journal
	Volume	395	Issue	10233	Pages	1343-1344
	Keywords
	Abstract	Inequities in access to the latest advances in health care and effective drugs constitute public health problems today,1 but was this also the case in ancient societies when practitioners used traditional medicines with limited means? The excavation of frozen graves in Yakutia (present day eastern Siberia, Russia) dating from 1700 CE2 led to the identification of a woman, buried almost naked, covered with a magnificent robe and with half a horse bit in her mouth (figure). The other half of the horse bit was found in the trunk behind her head with her earrings, bracelets, and signet rings.
	Programme	1038
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	Corporate Author				Thesis	Bachelor's thesis
	Publisher	Elsevier	Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	0140-6736, 1474-547X	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7666
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	Author	Hollingsworth James, Ye Lingling, Avouac Jean‐Philippe
	Title	Dynamically triggered slip on a splay fault in the Mw 7.8, 2016 Kaikoura (New Zealand) earthquake			Type	Journal
	Year	2017	Publication	Geophysical Research Letters	Abbreviated Journal
	Volume	44	Issue	8	Pages	3517-3525
	Keywords	correlation earthquake New Zealand rupture seismology slip inversion
	Abstract	Abstract We investigate the Mw 7.8, 2016 Kaikoura (New Zealand) earthquake by using optical satellite imagery and seismology to reveal the main features of the rupture process. Correlation of Landsat8 images reveals a 30?40?km surface rupture on the Kekerengu Fault and Jordan Thrust, with up to 12?m of right?lateral slip. A previously unrecognized conjugate strike?slip fault, the Papatea Fault, also slipped coseismically (3?4?m). The global centroid moment tensor (gCMT) centroid indicates both thrust and right?lateral slip and is located ~100?km NE of the main shock epicenter. The significant non?double?couple component of the gCMT (25%) suggests that the main shock is not well represented by a single planar fault. Back projection of teleseismic P waves reveals two main bursts of seismic radiation: (1) at 10?20?s, near the main shock epicenter, and (2) at ~70?s, close to the observed surface ruptures. We determine a finite source kinematic model of the rupture from the inversion of seismic waveforms. We use two faults in our model, defined to match the observed slip on the Kekerengu Fault, and a deeper offshore fault with a lower dip angle to satisfy the long period seismological observations. We compute the equivalent moment tensor from our finite source model and find it to be remarkably consistent with the gCMT solution. Although little is known about the geometry of these faults at depth, if the Kekerengu Fault splays from the deeper thrust, then it provides a rare example where the contribution of slip on a splay fault can be clearly isolated in the seismological waveforms.
	Programme	133
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0094-8276	ISBN	0094-8276	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6779
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	Author	Barruol Guilhem, Cordier Emmanuel, Bascou Jérôme, Fontaine Fabrice R., Legrésy Benoit, Lescarmontier Lydie
	Title	Tide‐induced microseismicity in the Mertz glacier grounding area, East Antarctica			Type	Journal
	Year	2013	Publication	Geophysical Research Letters	Abbreviated Journal
	Volume	40	Issue	20	Pages	5412-5416
	Keywords	Adélie land Antarctica cryoseismology icequakes Mertz glacier tide
	Abstract	AbstractThe deployment of a seismic network along the Adélie and George V coasts in East Antarctica during the period 2009?2012 provides the opportunity to monitor cryoseismic activity and to obtain new insights on the relationship between tidal cycles and coastal glacier dynamics. Here we focus on records from a seismometer located on a rocky outcrop in the vicinity of the grounding line of the 35 km broad Mertz glacier, a major outflow of this region. We detect numerous icequakes (50,000 events within 10 months and up to 100 events/h) and demonstrate their clear tidal modulation. We suggest that they result from ice friction and fracturing around the rocky peak and from the glacier flexure in response to the falling and rising tides at its grounding area. We propose that such icequake monitoring could be used as a climate proxy since grounding lines are subject to migrate with sea level changes.
	Programme	688
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0094-8276	ISBN	0094-8276	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6826
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	Author	Wöppelmann Guy, Marcos Marta, Santamaría‐Gómez Alvaro, Martín‐Míguez Belén, Bouin Marie‐Noëlle, Gravelle Médéric
	Title	Evidence for a differential sea level rise between hemispheres over the twentieth century			Type	Journal
	Year	2014	Publication	Geophysical Research Letters	Abbreviated Journal
	Volume	41	Issue	5	Pages	1639-1643
	Keywords	climate change geodesy GPS land motion sea level tide gauge
	Abstract	AbstractTide gauge records are the primary source of sea level information over multidecadal to century timescales. A critical issue in using this type of data to determine global climate?related contributions to sea level change concerns the vertical motion of the land upon which the gauges are grounded. Here we use observations from the Global Positioning System for the correction of this vertical land motion. As a result, the spatial coherence in the rates of sea level change during the twentieth century is highlighted at the local and the regional scales, ultimately revealing a clearly distinct behavior between the Northern and the Southern Hemispheres with values of 2.0?mm/yr and 1.1?mm/yr, respectively. Our findings challenge the widely accepted value of global sea level rise for the twentieth century.
	Programme	688
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0094-8276	ISBN	0094-8276	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6829
Permanent link to this record



	Author	Pitout F., Marchaudon A., Blelly P.‐L., Bai X., Forme F., Buchert S. C., Lorentzen D. A.
	Title	Swarm and ESR observations of the ionospheric response to a field‐aligned current system in the high‐latitude midnight sector			Type	Journal
	Year	2015	Publication	Geophysical Research Letters	Abbreviated Journal
	Volume	42	Issue	11	Pages	4270-4279
	Keywords	field‐aligned currents ionosphere
	Abstract	Abstract We present a conjunction between the Swarm fleet and the European Incoherent Scatter Svalbard Radar (ESR) on 9 January 2014. The Swarm orbit in the early phase of the mission gives us the unique opportunity of sequencing the temporal evolution of the observed field?aligned current system in the nightside, near magnetic local midnight. These field?aligned currents are seen to move poleward through the radar field of view and to affect the observed ionosphere. The upward field?aligned current (FAC) is responsible, at least in part, for the heating of the ionospheric electrons. It is less clear whether the downward FAC cools the ionosphere. We use the TRANSCAR model of the ionosphere to quantify the thermoelectric effect that comes into play. Finally, we compare the plasma parameters measured by the Langmuir probe on board Swarm and the ESR and conclude on an agreement within the errors.
	Programme	312
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0094-8276	ISBN	0094-8276	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6854
Permanent link to this record



	Author	Sara Labrousse, Jean-Baptiste Sallée, Alexander D. Fraser, Robert A. Massom, Phillip Reid, Michael Sumner, Christophe Guinet, Robert Harcourt, Clive McMahon, Frédéric Bailleul, Mark A. Hindell, Jean-Benoit Charrassin
	Title	Under the sea ice: Exploring the relationship between sea ice and the foraging behaviour of southern elephant seals in East Antarctica			Type	Journal
	Year	2017	Publication	Progress in Oceanography	Abbreviated Journal
	Volume	156	Issue		Pages	17-40
	Keywords
	Abstract	Investigating ecological relationships between predators and their environment is essential to understand the response of marine ecosystems to climate variability and change. This is particularly true in polar regions, where sea ice (a sensitive climate variable) plays a crucial yet highly dynamic and variable role in how it influences the whole marine ecosystem, from phytoplankton to top predators. For mesopredators such as seals, sea ice both supports a rich (under-ice) food resource, access to which depends on local to regional coverage and conditions. Here, we investigate sex-specific relationships between the foraging strategies of southern elephant seals (Mirounga leonina) in winter and spatio-temporal variability in sea ice concentration (SIC) and coverage in East Antarctica. We satellite-tracked 46 individuals undertaking post-moult trips in winter from Kerguelen Islands to the peri-Antarctic shelf between 2004 and 2014. These data indicate distinct general patterns of sea ice usage: while females tended to follow the sea ice edge as it extended northward, the males remained on the continental shelf despite increasing sea ice. Seal hunting time, a proxy of foraging activity inferred from the diving behaviour, was longer for females in late autumn in the outer part of the pack ice, ∼150–370km south of the ice edge. Within persistent regions of compact sea ice, females had a longer foraging activity (i) in the highest sea ice concentration at their position, but (ii) their foraging activity was longer when there were more patches of low concentration sea ice around their position (either in time or in space; 30days & 50km). The high spatio-temporal variability of sea ice around female positions is probably a key factor allowing them to exploit these concentrated patches. Despite lack of information on prey availability, females may exploit mesopelagic finfishes and squids that concentrate near the ice-water interface or within the water column (from diurnal vertical migration) in the pack ice region, likely attracted by an ice algal autumn bloom that sustains an under-ice ecosystem. In contrast, male foraging effort increased when they remained deep within the sea ice (420–960km from the ice edge) over the shelf. Males had a longer foraging activity (i) in the lowest sea ice concentration at their position, and (ii) when there were more patches of low concentration sea ice around their position (either in time or in space; 30days & 50km) presumably in polynyas or flaw leads between land fast and pack ice. This provides access to zones of enhanced resources in autumn or in early spring such as polynyas, the Antarctic shelf and slope. Our results suggest that some seals utilized a highly sea ice covered environment, which is key for their foraging effort, sustaining or concentrating resources during winter.
	Programme	109
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0079-6611	ISBN	0079-6611	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6643
Permanent link to this record



	Author	Nolwenn Béhagle, Cédric Cotté, Anne Lebourges-Dhaussy, Gildas Roudaut, Guy Duhamel, Patrice Brehmer, Erwan Josse, Yves Cherel
	Title	Acoustic distribution of discriminated micronektonic organisms from a bi-frequency processing: The case study of eastern Kerguelen oceanic waters			Type	Journal
	Year	2017	Publication	Progress in Oceanography	Abbreviated Journal
	Volume	156	Issue		Pages	276-289
	Keywords	Acoustics Euphausiid Kerguelen Myctophid Southern Ocean
	Abstract	Despite its ecological importance, micronekton remains one of the least investigated components of the open-ocean ecosystems. Our main goal was to characterize micronektonic organisms using bi-frequency acoustic data (38 and 120kHz) by calibrating an algorithm tool that discriminates groups of scatterers in the top 300m of the productive oceanic zone east of Kerguelen Islands (Indian sector of the Southern Ocean). The bi-frequency algorithm was calibrated from acoustic properties of mono-specific biological samples collected with trawls, thus allowing to discriminate three acoustic groups of micronekton: (i) “gas-bearing” (ΔSv,120-38<−1dB), (ii) “fluid-like” (ΔSv,120-38>2dB), and (iii) “undetermined” scatterers (−1<ΔSv,120-38<2dB). The three groups likely correspond biologically to gas-filled swimbladder fish (myctophids), crustaceans (euphausiids and hyperiid amphipods), and other marine organisms potentially present in these waters and containing either lipid-filled or no inclusion (e.g. other myctophids), respectively. The Nautical Area Scattering Coefficient (NASC) was used (echo-integration cells of 10m long and 1m deep) between 30 and 300m depth as a proxy of relative biomass of acoustic targets. The distribution of NASC values showed a complex pattern according to: (i) the three acoustically-defined groups, (ii) the type of structures (patch vs. layers) and (iii) the timing of the day (day/night cycle). NASC values were higher at night than during the day. A large proportion of scatterers occurred in layers while patches, that mainly encompass gas-bearing organisms, are especially observed during daytime. This method provided an essential descriptive baseline of the spatial distribution of micronekton and a relevant approach to (i) link micronektonic group to physical parameters to define their habitats, (ii) investigate trophic interactions by combining active acoustic and top predator satellite tracking, and (iii) study the functioning of the pelagic ecosystems at various spatio-temporal scales.
	Programme	109
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0079-6611	ISBN	0079-6611	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6655
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	Author	Claudio A. González-Wevar, Karin Gérard, Sebastian Rosenfeld, Thomas Saucède, Javier Naretto, Angie Díaz, Simon A. Morley, Paul Brickle, Elie Poulin
	Title	Cryptic speciation in Southern Ocean Aequiyoldia eightsii (Jay, 1839): Mio-Pliocene trans-Drake Passage separation and diversification			Type	Journal
	Year	2019	Publication	Progress in Oceanography	Abbreviated Journal
	Volume	174	Issue		Pages	44-54
	Keywords	Antarctic Peninsula Antarctic-Magellan Connection Biogeography Kerguelen Islands Morphometry Phylogeny South America Southern Ocean Systematics
	Abstract	The species of the genus Aequiyoldia Soot-Ryen, 1951, previously known as Yoldia, are common, soft-substratum, sareptid bivalves. In the Southern Ocean, Aequiyoldia eightsii (Jay, 1839) was originally described from the Antarctic Peninsula and has also been reported in southern South America. The species A. woodwardi (Hanley, 1960) was reported for the Falkland/Malvinas Islands and Tierra del Fuego, but this taxon has been recently synonymised within the broadly distributed A. eightsii. Aequiyoldia has received little attention across its distribution in the Southern Ocean, and although its taxonomy and systematics remain uncertain, all the species have been grouped under a single and broadly distributed unit: A. eightsii. Nevertheless, preliminary mtDNA comparisons demonstrated a marked genetic divergence (>7%) between A. eightsii populations from South America and Antarctic Peninsula. In order to further understand the diversity and biogeography of Aequiyoldia, we analyzed A. eightsii populations from different provinces of the Southern Ocean including South America (SA), the Falkland/Malvinas Islands (FI), the Antarctic Peninsula (AP), and Kerguelen Islands (KI). Individuals were characterized according to typical diagnostic morphological measurements and phylogenetic relationships were reconstructed based on mtDNA (cytochrome c oxidase subunit I). Patterns of genetic divergence of nucDNA intergenic transcribed spacers (ITS1, ITS2) were also estimated. The statistical analysis of external diagnostic characteristics revealed two morphotypes: (1) individuals with the morphology recorded for the nominal FI species, A. woodwardi, and (2) individuals from SA, AP, and KI, with the morphology recorded for A. eightsii. However, phylogenetic reconstructions based on mtDNA and nucDNA suggest the presence of at least five lineages within A. eightsii including: one lineage in Kerguelen Island, two lineages in the Antarctic Peninsula, one lineage in South America, and the last one restricted to the Falkland/Malvinas Islands. Such results are evidence that the Antarctic Polar Front represents an historical biogeographic barrier for this group and that after the separation of these lineages, they followed independent evolutionary pathways in different provinces of the Southern Ocean. Estimates of divergence time suggest that KI separated from other Aequiyoldia lineages close to the middle Miocene. Following this, the separation between the AP and SA lineages occurred at the end of the Miocene around 7.5 Ma. Finally, Aequiyoldia diversified during the Pliocene in Antarctic Peninsula (∼4.5 Ma) and South America (∼3.0 Ma). Individuals from FI exhibited morphological differences, and 4% of divergence from South American individuals, suggesting that A. woordwardi could be revalidated. Similarly, the marked molecular divergence between the KI and the rest of the recorded lineages also support the validity of A. kerguelensis (Thiele, 1931).
	Programme	1044
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	Corporate Author				Thesis	Bachelor's thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0079-6611	ISBN	0079-6611	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7129
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