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	Author	Ardhuin, F., F. Collard, B. Chapron, F. Girard-Ardhuin, G. Guitton, A. Mouche, J. Stopa
	Title	Estimates of ocean wave heights and attenuation in sea ice using the SAR wave mode on Sentinel-1A.			Type	Journal Article
	Year	2015	Publication	Geophysical Research Letters	Abbreviated Journal	0094-8276
	Volume	42	Issue	7	Pages	2317–2325
	Keywords
	Abstract	Swell evolution from the open ocean into sea ice is poorly understood, in particular the amplitude attenuation expected from scattering and dissipation. New synthetic aperture radar (SAR) data from Sentinel-1A wave mode reveal intriguing patterns of bright oscillating lines shaped like instant noodles. We investigate cases in which the oscillations are in the azimuth direction, around a straight line in the range direction. This observation is interpreted as the distortion by the SAR processing of crests from a first swell, due to the presence of a second swell. Since deviations from a straight line should be proportional to the orbital velocity toward the satellite, swell height can be estimated, from 1.5 to 5 m in the present case. The evolution of this 13 s period swell across the ice pack is consistent with an exponential attenuation on a length scale of 200 km.
	Programme	1090
	Campaign
	Address
	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	0094-8276	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6336
Permanent link to this record



	Author	Amélineau, F., Grémillet, D., Bonnet, D., Le Bot, T., & Fort, J.
	Title	Where to Forage in the Absence of Sea Ice? Bathymetry As a Key Factor for an Arctic Seabird			Type	Journal Article
	Year	2016	Publication	Plos one	Abbreviated Journal
	Volume	11	Issue	7	Pages	e0157764
	Keywords
	Abstract	The earth is warming at an alarming rate, especially in the Arctic, where a marked decline in sea ice cover may have far-ranging consequences for endemic species. Little auks, endemic Arctic seabirds, are key bioindicators as they forage in the marginal ice zone and feed preferentially on lipid-rich Arctic copepods and ice-associated amphipods sensitive to the consequences of global warming. We tested how little auks cope with an ice-free foraging environment during the breeding season. To this end, we took advantage of natural variation in sea ice concentration along the east coast of Greenland. We compared foraging and diving behaviour, chick diet and growth and adult body condition between two years, in the presence versus nearby absence of sea ice in the vicinity of their breeding site. Moreover, we sampled zooplankton at sea when sea ice was absent to evaluate prey location and little auk dietary preferences. Little auks foraged in the same areas both years, irrespective of sea ice presence/concentration, and targeted the shelf break and the continental shelf. We confirmed that breeding little auks showed a clear preference for larger copepod species to feed their chick, but caught smaller copepods and nearly no ice-associated amphipod when sea ice was absent. Nevertheless, these dietary changes had no impact on chick growth and adult body condition. Our findings demonstrate the importance of bathymetry for profitable little auk foraging, whatever the sea-ice conditions. Our investigations, along with recent studies, also confirm more flexibility than previously predicted for this key species in a warming Arctic.
	Programme	388
	Campaign
	Address
	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	1932-6203	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6518
Permanent link to this record



	Author	Passalacqua, O., Gagliardini, O., Parrenin, F., Todd, J., Gillet-Chaulet, F., and Ritz, C
	Title	Performance and applicability of a 2.5-D ice-flow model in the vicinity of a dome			Type	Journal Article
	Year	2016	Publication	Geosci. model dev.	Abbreviated Journal
	Volume	9	Issue	7	Pages	2301-2313
	Keywords
	Abstract	In ice-flow modelling, computing in 3-D requires a lot of resources, but 2-D models lack physical likelihood when the flow is diverging. That is why 2-D models accounting for the divergence, so-called 2.5-D models, are an interesting trade-off. However, the applicability of these 2.5-D models has never been systematically examined. We show that these models are ineffective in the case of highly diverging flows, but also for varying temperature, which was not suspected.
	Programme	902
	Campaign
	Address
	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	1991-9603	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6527
Permanent link to this record



	Author	Kernaléguen Laëtitia, Cherel Yves, Guinet Christophe, Arnould John PY
	Title	Mating success and body condition not related to foraging specializations in male fur seals			Type	Journal Article
	Year	2016	Publication	Royal society open science	Abbreviated Journal
	Volume	3	Issue	7	Pages	160143
	Keywords
	Abstract	Individual specialization is widespread among wild populations. While its fitness consequences are central in predicting the ecological and evolutionary trajectories of populations, they remain poorly understood. Long-term individual foraging specializations occur in male Antarctic (Arctocephalus gazella) and Australian (A. pusillus doriferus) fur seals. Strong selective pressure is expected in these highly dimorphic and polygynous species, raising the question of the fitness payoffs associated with different foraging strategies. We investigated the relationship between individual isotopic niche (a proxy of foraging specialization), body size and condition, and an index of reproductive success (harem size) in territorial males. Individuals varied greatly in their skin and fur isotopic values reflecting a range of foraging strategies within the two populations. However, in both species, isotopic niche was not correlated to body size, condition or mating success (R2/ρ < 0.06). Furthermore, no foraging niche was predominant in either species, which would have indicated a substantial long-term fitness benefit of a particular strategy via a higher survival rate. These results suggest that the fitness consequences of a foraging strategy depend not only on the quality of prey and feeding habitat but also on an individual's hunting efficiency and skills.
	Programme	109
	Campaign
	Address
	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	2054-5703	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6540
Permanent link to this record



	Author	J. Lilensten, M. Barthélemy, G. Besson, H. Lamy, M.G. Johnsen, J. Moen
	Title	The thermospheric auroral red line Angle of Linear Polarisation			Type	Journal Article
	Year	2016	Publication	Journal of geophysical research-space physics	Abbreviated Journal	J. Geophys. Res.
	Volume	121	Issue	7	Pages	2016JA022941
	Keywords
	Abstract	The auroral red line at 630 nm is linearly polarized. Up to now, only its Degree of LinearPolarization had been studied. In this article, we examine for the first time the Angle of Linear Polarization(AoLP) and we compare the measurements to the apparent angle of the magnetic field at the location ofthe red line emission. We show that the AoLP is a tracer of the magnetic field configuration. This opens newperspectives, both in the frame of space weather and in the field of planetology.
	Programme	1026
	Campaign
	Address
	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	0148-0227	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6541
Permanent link to this record



	Author	Fay Rémi, Barbraud Christophe, Delord Karine, Weimerskirch Henri
	Title	Variation in the age of first reproduction: different strategies or individual quality?			Type	Journal
	Year	2016	Publication	Ecology	Abbreviated Journal
	Volume	97	Issue	7	Pages	1842-1851
	Keywords	capture–mark–recapture individual heterogeneity life‐history plasticity reaction norm trade‐off Wandering Albatross
	Abstract	Abstract Although age at first reproduction is a key demographic parameter that is probably under high selective pressure, it is highly variable and the cause of this variability is not well understood. Two non?exclusive hypotheses may explain such variability. It could be the expression of different individual strategies, i.e., different allocation strategies in fitness components, or the consequences of individual difference in intrinsic quality, i.e., some individuals always doing better than others in all fitness components. We tested these hypotheses in the Wandering Albatross investigating relationships between the age at first reproduction and subsequent adult demographic traits. Using finite mixture capture recapture modeling, we demonstrate that the age at first reproduction is negatively related to both reproductive performances and adult survival, suggesting that individual quality was an important factor explaining variation in the age at first reproduction. Our results suggest that age at first breeding is a good predictor of quality in this long?lived seabird species.
	Programme	109
	Campaign
	Address
	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	0012-9658	ISBN	0012-9658	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6603
Permanent link to this record



	Author	Creasy Neala, Long Maureen D., Ford Heather A.
	Title	Deformation in the lowermost mantle beneath Australia from observations and models of seismic anisotropy			Type	Journal
	Year	2017	Publication	Journal of Geophysical Research: Solid Earth	Abbreviated Journal
	Volume	122	Issue	7	Pages	5243-5267
	Keywords	anisotropy lowermost mantle mantle dynamics postperovskite shear wave splitting
	Abstract	Abstract Observations of seismic anisotropy near the core?mantle boundary may yield constraints on patterns of lowermost mantle flow. We examine seismic anisotropy in the lowermost mantle beneath Australia, bounded by the African and Pacific Large Low Shear Velocity Provinces. We combined measurements of differential splitting of SKS?SKKS and S?ScS phases sampling our study region over a range of azimuths, using data from 10 long?running seismic stations. Observations reveal complex and laterally heterogeneous anisotropy in the lowermost mantle. We identified two subregions for which we have robust measurements of D??associated splitting for a range of ray propagation directions and applied a forward modeling strategy to understand which anisotropic scenarios are consistent with the observations. We tested a variety of elastic tensors and orientations, including single?crystal elasticity of lowermost mantle minerals (bridgmanite, postperovskite, and ferropericlase), tensors based on texture modeling in postperovskite aggregates, elasticity predicted from deformation experiments on polycrystalline MgO aggregates, and tensors that approximate the shape preferred orientation of partial melt. We find that postperovskite scenarios are more consistently able to reproduce the observations. Beneath New Zealand, the observations suggest a nearly horizontal [100] axis orientation with an azimuth that agrees well with the horizontal flow direction predicted by previous mantle flow models. Our modeling results further suggest that dominant slip on the (010) plane in postperovskite aggregates provides a good fit to the data but the solution is nonunique. Our results have implications for the mechanisms of deformation and anisotropy in the lowermost mantle and for the patterns of mantle flow.
	Programme	133
	Campaign
	Address
	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	2169-9313	ISBN	2169-9313	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6768
Permanent link to this record



	Author	Marchaudon A., Blelly P.‐L.
	Title	A new interhemispheric 16‐moment model of the plasmasphere‐ionosphere system: IPIM			Type	Journal
	Year	2015	Publication	Journal of Geophysical Research: Space Physics	Abbreviated Journal
	Volume	120	Issue	7	Pages	5728-5745
	Keywords	centrifugal acceleration interhemispheric exchanges mirror force temperature anisotropy
	Abstract	Abstract We present a new interhemispheric numerical model: the IRAP plasmasphere?ionosphere model (IPIM). This model describes the transport of the multispecies ionospheric plasma from one hemisphere to the other along convecting and corotating magnetic field lines, taking into account source processes at low altitude such as photoproduction, chemistry, and energization through the coupling with a kinetic code solving the transport of suprathermal electron along the field line. Among the new developments, a 16?moment?based approach is used for the transport equations in order to allow development of strong temperature anisotropy at high altitude and we consider important but often neglected effects, such as inertial acceleration (centrifugal and Coriolis). In this paper, after presenting in detail the principle of the model, we focus on preliminary results showing the original contribution of this new model. For these first runs, we simulate the convection and corotation transport of closed flux tubes in the plasmasphere for tilted/eccentric dipolar magnetic field configuration in solstice and equinox conditions. We follow different flux tubes between 1.2 and 6 Earth Radii (RE) and demonstrate the capability of the model to describe a wide range of density (above 15 orders of magnitude). The relevance of the mathematical approach used is highlighted, as anisotropies can develop above 3000?km in the plasmasphere as a result of the mirroring effect related to the anisotropic pressure tensor. Moreover, we show that the addition of inertial acceleration may become critical to describe plasma interhemispheric transport above 4RE. The ability of the model to describe the external plasmasphere is demonstrated, and innovative studies are foreseen, regarding the dynamics of the plasma along the magnetic field lines (in particular interhemispheric exchanges and ?opening?/?closure? of a flux tube).
	Programme	312
	Campaign
	Address
	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	2169-9380	ISBN	2169-9380	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6855
Permanent link to this record



	Author	Françoise Amélineau, David Grémillet, Delphine Bonnet, Tangi Le Bot, Jérôme Fort
	Title	Where to Forage in the Absence of Sea Ice? Bathymetry As a Key Factor for an Arctic Seabird			Type	Journal
	Year	2016	Publication	PLOS ONE	Abbreviated Journal
	Volume	11	Issue	7	Pages	e0157764
	Keywords	Birds Copepods Foraging Oceans Predation Sea ice Seabirds Zooplankton
	Abstract	The earth is warming at an alarming rate, especially in the Arctic, where a marked decline in sea ice cover may have far-ranging consequences for endemic species. Little auks, endemic Arctic seabirds, are key bioindicators as they forage in the marginal ice zone and feed preferentially on lipid-rich Arctic copepods and ice-associated amphipods sensitive to the consequences of global warming. We tested how little auks cope with an ice-free foraging environment during the breeding season. To this end, we took advantage of natural variation in sea ice concentration along the east coast of Greenland. We compared foraging and diving behaviour, chick diet and growth and adult body condition between two years, in the presence versus nearby absence of sea ice in the vicinity of their breeding site. Moreover, we sampled zooplankton at sea when sea ice was absent to evaluate prey location and little auk dietary preferences. Little auks foraged in the same areas both years, irrespective of sea ice presence/concentration, and targeted the shelf break and the continental shelf. We confirmed that breeding little auks showed a clear preference for larger copepod species to feed their chick, but caught smaller copepods and nearly no ice-associated amphipod when sea ice was absent. Nevertheless, these dietary changes had no impact on chick growth and adult body condition. Our findings demonstrate the importance of bathymetry for profitable little auk foraging, whatever the sea-ice conditions. Our investigations, along with recent studies, also confirm more flexibility than previously predicted for this key species in a warming Arctic.
	Programme	388
	Campaign
	Address
	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	1932-6203	ISBN	1932-6203	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6919
Permanent link to this record



	Author	Sauser Christophe, Delord Karine, Barbraud Christophe
	Title	Increased sea ice concentration worsens fledging condition and juvenile survival in a pagophilic seabird, the snow petrel			Type	Journal
	Year	2018	Publication	Biology Letters	Abbreviated Journal
	Volume	14	Issue	7	Pages	20180140
	Keywords
	Abstract	Polar sea ice is changing rapidly, threatening many taxa in the Arctic and the Antarctic. Little is known about the effects of sea ice on early life-history traits of sea ice specialist species, although juvenile stages are a critical component of population dynamics and recruitment. We examined how annual variation in sea ice concentration (SIC) affects juvenile survival and body condition at fledging in the snow petrel Pagodroma nivea using long-term datasets encompassing 22 years for body condition and 37 years for juvenile survival. We show that SIC and southern annular mode (SAM), the principal mode of variability of the atmospheric circulation in the Southern Hemisphere, have strong nonlinear effects on juvenile survival and body condition. Below ca 20–30% SIC, body condition remained stable, but decreased almost linearly for higher SIC. Juvenile survival was negatively related to SIC and to SAM during the chick rearing period. We suggest that the base of the sea ice food web would be directly affected by sea ice conditions, thus acting locally on the abundance and structure of prey communities.
	Programme	109
	Campaign
	Address
	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	1744-9561	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7126
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