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	Author	Dartois E, Engrand C, Brunetto R, Duprat J, Pino T, Quirico E, Remusat L, Bardin N, Briani G, Mostefaoui S, Morinaud G, Crane B, Szwec N, Delauche L, Jamme F, Sandt Ch, Dumas P,
	Title	UltraCarbonaceous Antarctic micrometeorites, probing the Solar System beyond the nitrogen snow-line			Type	Journal Article
	Year	2013	Publication	Icarus	Abbreviated Journal
	Volume	224	Issue	1	Pages	243-252
	Keywords	Origin, Solar System, Interplanetary dust, Cosmochemistry, Cosmic rays, Organic chemistry,
	Abstract	The current Solar System architecture is aheritage of the protoplanetary disk that surrounded the young Sun, 4.56 Gy ago. Primitive extraterrestr ial objects provide means to trace back the primordial composi- tion and radial distribution of matter in this disk. Here, we present acombined micro-IR, Raman, chem- ical and isotopic study of two ultracarbonaceous micrometeorites recovered from Antar ctica (UCAMMs). This study reveals particles containing an unusually high nitrogen- and deuterium-rich organic matter analogous to a polyaromatic hydrogenated carbon nitride, characterized by nitrogen concentration with bulk atomic N/C ratios of 0.05 and 0.12 (locallyexceeding 0.15).We propose that such nitrogen-rich car- bonaceous material can be formed by energetic irradiations of nitrogen-rich ices in very low temperature regions of the Solar System. Such conditions are encountered at the surface of small objects beyond the trans-neptunian region. UCAMMs provide unique insights on physico-chemical processes that occurred beyond the nitrogen snow-line, revealing orga nic material from the extreme outer regions of the Solar System that cannot be investigated by remote sensing methods.
	Programme	1120
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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	0019-1035	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	4827
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	Author	Aude Villemain, Patrice Godon
	Title	Toward a resilient organization: The management of unexpected hazard on the polar traverse			Type	Journal
	Year	2017	Publication	Safety Science	Abbreviated Journal
	Volume	95	Issue		Pages	210-218
	Keywords	Organizational resilience Polar conditions Proactive–reactive adjustments Safety management Unexpected events
	Abstract	The aim of this research is to understand the organizational resilience through the safety management when unexpected events occurred, on an atypical transport environment, the polar traverse. Three polar traverses were studied, one of which being a detailed case study. Thus, ethnological observations over 3year periods from 2012 to 2015 (to understand the traverse logic, functioning through unexpected event) and all-day interviews during a traverse (to understand actions and strategies of organizational resilience to cope unforeseen events) were collected. The main results, from quantitative and qualitative analysis, indicated (1) mechanical, organizational and both interventions allowed to face unexpected incidents on the traverse, (2) great possibilities to take actions on the convoy organization enabled to develop a pro-active management of the safety in alternation with reactive adjustments; (3) the importance was to preserve the machines functionality even if operators have to face environment hostility to repair; and (4) the variation of the convoy organization was permanent in its whole even if the incidents concerned only one road track. The strategies of organizational resilience building will be discussed in this article, around the proactive–reactive management, the organizational dynamic, the risk evaluation, and the risk taken to preserve the room manoeuver.
	Programme	1199
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0925-7535	ISBN	0925-7535	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7327
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	Author	Spracklen, D.V.; Arnold, S.R.; Sciare, J.; Carslaw, K.S.; Pio, C.
	Title	Globally significant oceanic source of organic carbon aerosol			Type	Journal Article
	Year	2008	Publication	Geophysical research letters	Abbreviated Journal
	Volume	35	Issue		Pages
	Keywords	organic carbon; ocean; aerosol; 0305 Atmospheric Composition and Structure: Aerosols and particles; 0315 Atmospheric Composition and Structure: Biosphere/atmosphere interactions; 0312 Atmospheric Composition and Structure: Air/sea constituent fluxes
	Abstract	Significant concentrations of organic carbon (OC) aerosol are observed at three oceanic surface sites (Amsterdam Island, Azores and Mace Head). Two global chemical transport models (CTMs) underpredict OC concentrations at these sites (normalised mean bias of ?67% and ?58%). During periods of high biological activity monthly mean concentrations are underpredicted by a factor of 5–20. At Amsterdam Island and Mace Head, observed OC correlates well (R2 = 0.61–0.77) with back-trajectory weighted chlorophyll-a, suggesting an oceanic OC source driven by biological activity. We use a combination of remote sensed chlorophyll-a, back trajectories and observed OC to derive an empirical relation between chlorophyll-a and the total oceanic OC emission flux. Using the GEOS-chem CTM we show a global oceanic OC emission, from primary and secondary sources, of ?8 Tg/year matches observations. This emission is comparable in magnitude to the fossil fuel OC source and increases the simulated global OC burden by 20%.
	Programme	414;415
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	Corporate Author				Thesis	Bachelor's thesis
	Publisher	American Geophysical Union	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	IPEV @ Thierry.Lemaire @			Serial	5523
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	Author	Sciare J, Favez O, Sarda-Estve R, Oikonomou K, Cachier H, Kazan V,
	Title	Long-term observations of carbonaceous aerosols in the Austral Ocean atmosphere: Evidence of a biogenic marine organic source			Type	Journal Article
	Year	2009	Publication	J. Geophys. Res.	Abbreviated Journal	J. Geophys. Res.
	Volume	114	Issue	D15	Pages	D15302 -
	Keywords	organic aerosols, black carbon, biogenic aerosols, Austral Ocean, chlorophyll a, 0305 Atmospheric Composition and Structure: Aerosols and particles, 0365 Atmospheric Composition and Structure: Troposphere: composition and chemistry, 3339 Atmospheric Processes: Ocean/atmosphere interactions,
	Abstract	Long-term observations of carbonaceous aerosols in the Austral Ocean are reported here for the first time from almost 5 years of continuous filter sampling performed at Amsterdam Island (3748S, 7734E). Black carbon concentrations determined by optical method were among the lowest reported for marine atmosphere, with monthly mean levels ranging from 2–5 ng C/m3 during summer to 7–13 ng C/m3 during winter. A clear seasonal pattern was also observed for organic aerosols, but in opposite phase, with maximum values during the austral summer period (>250 ng C/m3) and minimum concentrations (100 ng C/m3) during winter. This seasonal variation of organic concentration was found to be almost entirely related to the water-insoluble organic carbon fraction, suggesting a primary origin for these organics, most probably through bubble bursting processes. Moreover, this summer maximum observed for organic aerosols was found to be correlated with satellite-derived chlorophyll a concentrations averaged over an oceanic region upwind of the sampling site and characterized by relatively high biogenic activity. This oceanic region being located at 1000–2000 km far away from the monitoring station, atmospheric ageing may have played a significant role on the levels and size-resolved properties of marine organics collected at Amsterdam Island. This biogenic marine organic source of primary origin in the Austral Ocean is fully consistent with similar observations previously reported for the Northern Atlantic Ocean and brings further evidences of the major role of marine organic emissions over remote oceanic regions.
	Programme	414;415;416
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	Corporate Author				Thesis	Bachelor's thesis
	Publisher	AGU	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	1819
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	Author	Caro Samuel P, Balthazart Jacques, Bonadonna Francesco,
	Title	The perfume of reproduction in birds: Chemosignaling in avian social life			Type	Journal Article
	Year	2015	Publication	Hormones and Behavior	Abbreviated Journal
	Volume	68	Issue		Pages	25-42
	Keywords	Olfaction, Pheromone, Avian, Sexual selection recognition,
	Abstract	Chemical cues were probably the first cues ever used to communicate and are still ubiquitous among living organisms. Birds have long been considered an exception: it was believed that birds were anosmic and relied on their acute visual and acoustic capabilities. Birds are however excellent smellers and use odors in various contexts including food searching, orientation, and also breeding. Successful reproduction in most vertebrates involves the exchange of complex social signals between partners. The first evidence for a role of olfaction in reproductive contexts in birds only dates back to the seventies, when ducks were shown to require a functional sense of smell to express normal sexual behaviors. Nowadays, even if the interest for olfaction in birds has largely increased, the role that bodily odors play in reproduction still remains largely understudied. The few available studies suggest that olfaction is involved in many reproductive stages. Odors have been shown to influence the choice and synchronization of partners, the choice of nest-buildingmaterial or the care for the eggs and offspring. How this chemical information is translated at the physiological level mostly remains to be described, although available evidence suggests that, as in mammals, key reproductive brain areas like the medial preoptic nucleus are activated by relevant olfactory signals. Olfaction in birds receives increasing attention and novel findings are continuously published, but many exciting discoveries are still ahead of us, and could make birds one of the animal classes with the largest panel of developed senses ever described.
	Programme	354
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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	0018-506X	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	4997
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	Author	Homberg, C.; Bergerat, F.; Angelier, J.; Garcia, S.
	Title	Fault interaction and stresses along broad oceanic transform zone: Tjrnes Fracture Zone, north Iceland			Type	Journal Article
	Year	2010	Publication	Tectonics	Abbreviated Journal
	Volume	29	Issue	1	Pages	TC1002
	Keywords	oceanic transform; fault interaction; stresses; Iceland; slip transfer; 8150 Tectonophysics: Plate boundary: general; 8164 Tectonophysics: Stresses: crust and lithosphere; 8020 Structural Geology: Mechanics, theory, and modeling
	Abstract	Transform motion along oceanic transforms generally occurs along narrow faults zones. Another class of oceanic transforms exists where the plate boundary is quite large (∼100 km) and includes several subparallel faults. Using a 2-D numerical modeling, we simulate the slip distribution and the crustal stress field geometry within such broad oceanic transforms (BOTs). We examine the possible configurations and evolution of such BOTs, where the plate boundary includes one, two, or three faults. Our experiments show that at any time during the development of the plate boundary, the plate motion is not distributed along each of the plate boundary faults but mainly occurs along a single master fault. The finite width of a BOT results from slip transfer through time with locking of early faults, not from a permanent distribution of deformation over a wide area. Because of fault interaction, the stress field geometry within the BOTs is more complex than that along classical oceanic transforms and includes stress deflections close to but also away from the major faults. Application of this modeling to the 100 km wide Tjrnes Fracture Zone (TFZ) in North Iceland, a major BOT of the Mid-Atlantic Ridge that includes three main faults, suggests that the Dalvik Fault and the Husavik-Flatey Fault developed first, the Grismsey Fault being the latest active structure. Since initiation of the TFZ, the Husavik-Flatey Fault accommodated most of the plate motion and probably persists until now as the main plate structure.
	Programme	316
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	Corporate Author				Thesis
	Publisher	AGU	Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0278-7407	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number	IPEV @ Thierry.Lemaire @			Serial	6062
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	Author	Pontier Dominique, Fouchet David, Bried Jol,
	Title	Can cat predation help competitors coexist in seabird communities?			Type	Journal Article
	Year	2010	Publication	Journal of Theoretical Biology	Abbreviated Journal	J. Theor. Biol.
	Volume	262	Issue	1	Pages	90 -96
	Keywords	Oceanic islands, Seabirds, Feral cats, Nest site availability, Date of arrival, Community structure, Predator-prey relationships, Model,
	Abstract	On oceanic islands, nest site availability can be an important factor regulating seabird population dynamics. The potential for birds to secure a nest to reproduce can be an important component of their life histories. The dates at which different seabird species arrive at colonies to breed will have important consequences for their relative chances of success. Early arrival on the island allows birds to obtain nests more easily and have higher reproductive success. However, the presence of an introduced predator may reverse this situation. For instance, in the sub-Antarctic Kerguelen archipelago, early arriving birds suffer heavy predation from introduced cats. Cats progressively switch from seabirds to rabbits, since the local rabbit population starts to peak after early arriving seabird species have already returned to the colony. When late-arriving birds arrive, cat predation pressure on seabirds is thus weaker. In this paper, we investigate the assumption that the advantage of early nest mnopolization conferred to early arriving birds may be counterbalanced by the cost resulting from predation. We develop a mathematical model representing a simplified situation in which two insular seabird species differ only in their arrival date at the colony site and compete for nesting sites. We conclude that predation may ensure the coexistence of the two bird species or favor the late-arriving species, but only when seasonal variations in predation pressure are large. Interestingly, we conclude that arriving early is only favorable until a given level where high reproductive success no longer compensates for the long exposure to strong predation pressure. Our work suggests that predation can help to maintain the balance between species of different phenologies.
	Programme	279
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	Corporate Author				Thesis
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	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-5193	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	141
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	Author	Beine Harry, Anastasio Cort, Domine Florent, Douglas Thomas, Barret Manuel, France James, King Martin, Hall Sam, Ullmann Kirk,
	Title	Soluble chromophores in marine snow, seawater, sea ice and frost flowers near Barrow, Alaska			Type	Journal Article
	Year	2012	Publication	J. Geophys. Res.	Abbreviated Journal
	Volume	117	Issue		Pages	D00R15-
	Keywords	OASIS, chromophores, colored dissolved organic matter (CDOM), frost flowers, light absorption, marine, 0317 Atmospheric Composition and Structure: Chemical kinetic and photochemical properties, 0322 Atmospheric Composition and Structure: Constituent sources and sinks, 0736 Cryosphere: Snow (1827, 1863), 0750 Cryosphere: Sea ice (4540), 4807 Oceanography: Biological and Chemical: Chemical speciation and complexation,
	Abstract	We measured light absorption in 42 marine snow, sea ice, seawater, brine, and frost flower samples collected during the OASIS field campaign between February 27 and April 15, 2009. Samples represented multiple sites between landfast ice and open pack ice in coastal areas approximately 5 km west of Barrow, Alaska. The chromophores that are most commonly measured in snow, H2O2, NO3-, and NO2-, on average account for less than 1% of sunlight absorption in our samples. Instead, light absorption is dominated by unidentified “residual” species, likely organic compounds. Light absorption coefficients for the frost flowers on first-year sea ice are, on average, 40 times larger than values for terrestrial snow samples at Barrow, suggesting very large rates of photochemical reactions in frost flowers. For our marine samples the calculated rates of sunlight absorption and OH production from known chromophores are (0.1–1.4) 1014 (photons cm-3 s-1) and (5–70) 10-12 (mol L-1 s-1), respectively. Our residual spectra are similar to spectra of marine chromophoric dissolved organic matter (CDOM), suggesting that CDOM is the dominant chromophore in our samples. Based on our light absorption measurements we estimate dissolved organic carbon (DOC) concentrations in Barrow seawater and frost flowers as approximately 130 and 360 μM C, respectively. We expect that CDOM is a major source of OH in our marine samples, and it is likely to have other significant photochemistry as well.
	Programme	1017
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	Corporate Author				Thesis
	Publisher	AGU	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	989
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	Author	Jérémy Grenier, Najat Bhiry, Armelle Decaulne
	Title	Meteorological conditions and snow-avalanche occurrence over three snow seasons (2017–2020) in Tasiapik Valley, Umiujaq, Nunavik			Type	Journal
	Year	2023	Publication	Arctic, Antarctic, and Alpine Research	Abbreviated Journal
	Volume	55	Issue	1	Pages	2194492
	Keywords	Nunavik snow avalanches Time-lapse cameras weather data
	Abstract	In this article, we study snow avalanche activity during the snow seasons of 2017–2020 using four automatic time-lapse cameras strategically positioned along the southwestern slope of Tasiapik Valley, near the village of Umiujaq, in Nunavik (northern Québec, Canada). Over the three snow seasons, cameras helped to detect evidence of 130 avalanche events, scattered over seventy-eight distinct avalanche days. The evolution of weather conditions prior to each avalanche release was detailed according to data from a nearby weather station. Moreover, the time of release, the release type, the surface texture, and whether rocky material was present in the deposits were documented from the photographs. To explore relationships between weather data and avalanche releases, conditional inference tree (CIT) analysis was conducted. Results of the CIT analysis showed that there are different weather patterns associated with avalanche releases depending on the season, and significant thresholds values were defined. In winter, the avalanche probability was greater when three-day snowfall total exceeded 10 cm. In spring, the avalanche probability was greater when cumulative melting degree-days were less than forty-six and when daily minimum air temperature was greater than 2°C. Moreover, cornice failures were found to be a major component of the avalanche dynamic in Tasiapik Valley, mainly because of the slope’s morphology. They have also been the cause of the three largest volume and longest runout avalanches observed by cameras in this study, highlighting potential risks for local communities. The probability of observing cornice failures is enhanced on days when maximum air temperature is greater than −8°C in winter conditions, whereas in spring conditions it is enhanced by daily maximum air temperature greater than 2.5°C. This study represents a necessary first step toward avalanche forecasting based on weather data in Nunavik. Efforts should be continued given the expected higher frequency of natural hazards in northern regions as a consequence of recent climate changes.
	Programme	1148
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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	1523-0430	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8695
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	Author	A. Jamelot, A. Gailler, Ph. Heinrich, A. Vallage, J. Champenois
	Title	Tsunami Simulations of the Sulawesi Mw 7.5 Event: Comparison of Seismic Sources Issued from a Tsunami Warning Context Versus Post-Event Finite Source			Type	Journal
	Year	2019	Publication	Pure and applied geophysics	Abbreviated Journal
	Volume	176	Issue		Pages	3351-3376
	Keywords	numerical modelling strike-slip Sulawesi supershear Tsunami
	Abstract	The 28 September 2018 Sulawesi earthquake generated a much larger tsunami than expected from its Mw = 7.5 magnitude and from its dominant strike-slip mechanism. Within a few minutes after the earthquake, the tsunami devastated the seafront of Palu bay, destroying houses and infrastructures over a few hundred meters. Coastal subsidence and slumping at various locations around the bay were also observed. There is debate in the scientific community as to whether submarine landslides and shore collapses contributed to the generation of strong and destructive waves locally. The objective of this study is threefold: first, to determine whether standard seismic inversions could predict the source in the context of tsunami early warning; second, to define a new seismic source built from optical image correlation and based on the geological and tectonic context; third, to assess whether the earthquake alone is able to generate up to 9-m wave heights at the coast. Numerical simulations of the tsunami propagation are performed for different seismic dislocation sources. Nonlinear shallow water equations are solved by a finite-difference method in grids with 200-m and 10-m resolutions. The early CMT focal solutions calculated by seismological institutes show dominant strike-slip mechanisms with a homogenous slip distribution. These sources produce maximum tsunami heights of 40-cm on the coast of Palu city. Two heterogeneous sources are tested and compared: the USGS “finite fault” model calculated from seismic inversion and a new “hybrid” source inferred from different techniques. The latter is based on a segmented fault in agreement with the geological context and built from both from seismic parameters of a CMT solution and the observed horizontal ground displacements. This source produces water wave heights of 4 to 5-m in the Palu bay. The observed inundation heights and distances are reproduced satisfactorily by the model at Pantoloan and at the southwestern tip of Palu bay. However, the “hybrid” source is unable to reproduce the largest 8 to 12-m water heights as reported from field surveys. Thus, even though this “hybrid” source produces most of the reported tsunami energy, we cannot exclude that the numerous coastal collapses observed in Palu bay contributed to increase the local tsunami run-up.
	Programme	133
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0033-4553	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7886
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