French Polar Institute Literature Database -- Query Results

	French Polar Institute Literature Database Home \| Show All \| Simple Search \| Advanced Search	Login Quick Search: Field: contains: ...
	51–60 of 8781 records found matching your query (RSS \| history):

Select All Deselect All

<< 1 2 3 4 5 6 7 8 9 10 >> [11–20]

List View

Citations

Details

	Records
	Author	J-C Gallet, P. Björkman, CP Borstad, AJ Hodson, H-W Jacobi, C Larose, B Luks, A Spolaor, TV Schuler, A Urazgildeeva, C Zdanowicz
	Title	Snow research in Svalbard: Current status and knowledge gaps			Type	Report
	Year	2019	Publication	E. orr, g. hansen, h. lappalainen, c. hübner, and h. lihavainen (eds.), SESS report 2018, the state of environmental science in svalbard – an annual report	Abbreviated Journal
	Volume		Issue		Pages	82-107
	Keywords	snow, climate, cryosphere, glaciology, ecology, sea-ice
	Abstract
	Programme	1126
	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	2535-6321	ISBN	978-82-691528-0-7	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7544
Permanent link to this record



	Author	Aristidi E., Agabi K., Fossat E., Azouit M., Martin F., Sadibekova T., Travouillon T., Vernin J. & Ziad A.
	Title	Site testing in summer at Dome C, Antarctica.			Type	Journal Article
	Year	2005	Publication	Astronomy & astrophysics	Abbreviated Journal
	Volume	444	Issue	2	Pages	651-659
	Keywords	site testing
	Abstract	We present summer site testing results based on DIMM data obtained at Dome C, Antarctica. These data were collected on the bright star Canopus during two 3-months summer campaigns in 2003-2004 and 2004-2005. We performed continuous monitoring of the seeing and the isoplanatic angle in the visible. We found a median seeing of 0.54'' and a median isoplanatic angle of 6.8''. The seeing appears to have a deep minimum around 0.4'' almost every day in late afternoon.
	Programme	908
	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	0004-6361	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	3141
Permanent link to this record



	Author	Agabi, A.; Aristidi, E.; Azouit, M.; Fossat, E.; Martin, F.; Sadibekova, T.; Vernin, J.; Ziad, A.
	Title	First Whole Atmosphere Nighttime Seeing Measurements at Dome C, Antarctica			Type	Journal Article
	Year	2006	Publication	The Publications of the Astronomical Society of the Pacific	Abbreviated Journal	Publ. Astron. Soc. Pac.
	Volume	118	Issue	840	Pages	344-348
	Keywords	Site Testing
	Abstract	We report site-testing results obtained in the nighttime during the polar autumn and winter at Dome C. These results were collected during the first Concordia winterover by A. Agabi. They are based on seeing and isoplanatic angle monitoring, as well as in situ balloon measurements of the refractive index structure constant profiles C2n(h). Atmosphere is divided into two regions: (1) a 36 m high surface layer responsible for 87% of the turbulence, and (2) a very stable free atmosphere above, with a median seeing of 0.36“ +/- 0.19” at an elevation of h=30 m. The median seeing measured with a differential image motion monitor placed on top of an 8.5 m high tower is 1.3“ +/- 0.8”.
	Programme	908
	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	0004-6280	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	3180
Permanent link to this record



	Author	Lautredou A-C, Motomura H, Gallut C, Ozouf-Costaz C, Cruaud C, Lecointre G, Dettai A,
	Title	New nuclear markers and exploration of the relationships among Serraniformes (Acanthomorpha, Teleostei): The importance of working at multiple scales			Type	Journal Article
	Year	2013	Publication	Molecular Phylogenetics and Evolution	Abbreviated Journal	Mol. Phylogenet. Evol.
	Volume	67	Issue	1	Pages	140-155
	Keywords	Serraniformes, Scorpaenidae, Nuclear genes, Phylogeny, Scorpaeniformes, Perciformes,
	Abstract	We explore the relationships within Serraniformes (Li et al., 2009) using a dense taxon sampling and seven nuclear markers. Six had already used been for teleost phylogeny (IRBP, MC1R, MLL4, Pkd1, Rhodopsin, and RNF213) at other scales, and one (MLL2) is new. The results corroborate the composition of Serraniformes described in previous publications (some Gasterosteiformes, Perciformes and Scorpaeniformes). Within the clade, Notothenioidei and Zoarcoidei are each monophyletic. Cottoidei was not monophyletic due to placement of the genus Ebinania (Psychrolutidae). Our independent data confirm the sister-group relationship of Percophidae and Notothenioidei as well as the division of Platycephaloidei in four different groups (Bembridae, Platycephalidae, Hoplichthyidae and Peristediidae with Triglidae). Within Cottoidei, Liparidae and Cyclopteridae formed a clade associated with Cottidae, the genus Cottunculus (Psychrolutidae), and Agonidae. Serranidae and Scorpaenidae are not monophyletic, with the Serranidae divided in two clades (Serraninae and Epinephelinae/Anthiinae) and Scorpaenidae including Caracanthidae and the genus Ebinania (Psychrolutidae). We discuss some morphological characters supporting clades within the Scorpaenidae.
	Programme	1124
	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	1055-7903	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	4834
Permanent link to this record



	Author	Trampert, J.; Snieder, R.
	Title	Model Estimations Biased by Truncated Expansions: Possible Artifacts in Seismic Tomography			Type	Journal Article
	Year	1996	Publication	Science	Abbreviated Journal	Science
	Volume	271	Issue	5253	Pages	1257-1260
	Keywords	seismology ; tomography ; errors ; mathematical models ; methods ; inverse problem ; elastic waves ; Rayleigh waves ; algorithms
	Abstract	In most linear imaging problems, where the model to be sought is expanded in a set of basis functions, it is common practice to truncate the set at a certain (arbitrary) level. The solution then depends on the chosen parameterization, and neglected basis functions may leak into the solution to produce artifacts in the retrieved model. An unbiased estimate of the coefficients of the true model may be obtained in the chosen finite basis set ; here, a method to suppress leakage is illustrated on an example of global seismic tomography.
	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	0036-8075	ISBN		Medium
	Area		Expedition		Conference
	Notes	10.1126/science.271.5253.1257			Approved	yes
	Call Number	IPEV @ Thierry.Lemaire @			Serial	5615
Permanent link to this record



	Author	Stutzmann Elonore, Schimmel Martin, Patau Genevive, Maggi Alessia,
	Title	Global climate imprint on seismic noise			Type	Journal Article
	Year	2009	Publication	Geochem. Geophys. Geosyst.	Abbreviated Journal
	Volume	10	Issue	11	Pages	Q11004 -
	Keywords	seismic noise, microseisms, seismology, 7255 Seismology: Surface waves and free oscillations, 7299 Seismology: General or miscellaneous,
	Abstract	In the absence of earthquakes, oceanic microseisms are the strongest signals recorded by seismic stations. Using the GEOSCOPE global seismic network, we show that the secondary microseism spectra have global characteristics that depend on the station latitude and on the season. In both hemispheres, noise amplitude is larger during local winter, and close to the equator, noise amplitude is stable over the year. There is an excellent correlation between microseism amplitude variations over the year and changes in the highest wave areas. Considering the polarization of the secondary microseisms, we show that stations in the Northern Hemisphere and close to the equator record significant changes of the secondary microseism source azimuth over the year. During Northern Hemisphere summer, part or all of the sources are systematically located farther toward the south than during winter. Stations in French Guyana (MPG) and in Algeria (TAM) record microseisms generated several thousand kilometers away in the South Pacific Ocean and in the Indian Ocean, respectively. Thus, secondary microseism sources generated by ocean waves which originate in the Southern Hemisphere can be recorded by Northern Hemisphere stations when local sources are weak. We also show, considering a station close to Antarctica, that primary and secondary microseism noise amplitudes are strongly affected by changes of the sea ice floe and that sources of these microseisms are in different areas. Microseism recording can therefore be used to monitor climate changes.
	Programme	133
	Campaign
	Address
	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	1525-2027	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	1920
Permanent link to this record



	Author	Hu X G, Liu L T, Kroner C, Sun H P,
	Title	Observation of the seismic anisotropy effects on free oscillations below 4 mHz			Type	Journal Article
	Year	2009	Publication	Journal of Geophysical Research: Solid Earth	Abbreviated Journal	J. Geophys. Res.
	Volume	114	Issue	B7	Pages	B07301-
	Keywords	seismic anisotropy, free oscillations of the earth, mixed-type mode coupling, 7255 Surface waves and free oscillations, 7208 Mantle, 7299 General or miscellaneous,
	Abstract	We present observations of significant fundamental spheroidal-toroidal mode coupling at frequencies below 4 mHz in the early part of vertical component records from seismic stations on near-equatorial source-receiver propagation paths after the 26 December 2004 and 28 March 2005 great Sumatra earthquakes. Since the mixed-type coupling induced by rotational Coriolis force are very weak at these selected equatorial-path stations, we investigate what effects mimic the strong Coriolis effects at frequencies below 4 mHz, suggesting that local azimuthal anisotropy in the upper mantle is the most likely explanation for the strong anomalous coupling we observed. In addition, strong anisotropy coupling observed in the frequency band of 14 mHz is always characterized by anomalous small amplitudes of coupled spheroidal modes on the vertical component of seismograph, suggesting that excitation of quasi-toroidal modes by azimuthal anisotropy associates with geometric nodes of fundamental spheroidal modes.
	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	2156-2202	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	57
Permanent link to this record



	Author	Mengesha S., Dehairs F., Fiala M., Elskens M. & Goeyens L.
	Title	Seasonal variation of phytoplankton community structure and nitrogen uptake regime in the Indian sector of the southern ocean.			Type	Journal Article
	Year	1998	Publication	Polar biology	Abbreviated Journal	Polar Biol.
	Volume	20	Issue	4	Pages	259-272
	Keywords	Seasonal variation ; Phytoplankton ; Biomass ; Plant community ; Nitrogen cycle ; Absorption ; Southern Ocean ; Indian Ocean ; Algae ; Community structure ; Marine environment ; Thallophyta
	Abstract	This study investigates the dynamics of phytoplankton communities and nitrogen uptake in the Indian sector of the Southern Ocean during spring and summer. The study area is oligotrophic (Chl a stocks < 50 mg m-2); nevertheless, a large spatial variation of phytoplankton biomass and community structure was observed. During both seasons the phytoplankton community in the seasonal ice zone showed higher biomasses and was mainly composed of large diatom cells. However, in the permanently open ocean zone the community had low biomass and was chiefly composed of nano- and picoflagellates. In the polar front zone, although biomass was higher, the community structure was similar to the open ocean zone. The results suggest that the variation in phytoplankton community structure on a larger scale resonates with gradients in water column stability and nutrient distribution. However, significant changes in biomass and nutrient stocks but little change in community structure were observed. Absolute nitrogen uptake rates were generally low, but their seasonal variations were highly significant. During spring the communities displayed high specific nitrate uptake (mean rate = 0.0048 h-1). and diatoms (in the seasonal ice zone) as well as nano- and picoflagellates (in the permanently open ocean zone and polar front zone) were mainly based on new production (mean f-ratio = 0.69). The transition to summer was accompanied by a significant reduction in nitrate uptake rate (0.0048 h-1 ? 0.0011 h-1) and a shift from predominantly new to regenerated production (f-ratio 0.69 ? 0.39). Ammonium played a major role in the seasonal dynamics of phytoplankton nutrition. The results emphasize that, despite a large contrast in community structure, the seasonal dynamics of the nitrogen uptake regime and phytoplankton community structure in all three subsystems were similar. Additionally, this study supports our previous conclusion that the seasonal shift in nitrogen uptake regime can occur with, as well as without, marked changes in community structure.
	Programme	193
	Campaign
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Berlin	Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0722-4060	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	2108
Permanent link to this record



	Author	Bost, C.A.; Cott, C.; Bailleul, F.; Cherel, Y.; Charrassin, J.B.; Guinet, C.; Ainley, D.G.; Weimerskirch, H.
	Title	The importance of oceanographic fronts to marine birds and mammals of the southern oceans			Type	Journal Article
	Year	2009	Publication	Journal of Marine Systems	Abbreviated Journal	Special Issue on Observational Studies of Oceanic Fronts
	Volume	78	Issue	3	Pages	363-376
	Keywords	Seabird; Sea mammals; Fronts; Foraging strategies; Bio-logging
	Abstract	During the last 30years, at-sea studies of seabirds and marine mammals in the oceans south of the Subtropical Front have described an association with major frontal areas. More recently, the advancement in microtechnology has allowed the tracking of individuals and investigations into how these marine predators actually use the frontal zones. In this review, we examine 1) the relative importance to apex predators of the different frontal zones in terms of spatial distribution and carbon flux; 2) the processes that determine their preferential use; and 3) how the mesoscale dynamics of frontal structures drive at-sea foraging strategies of these predators. We review published results from southern waters and place them in a broader context with respect to what has been learned about the importance of fronts in oceans farther north. Some fronts constitute important boundaries for seabird communities in southern waters. At a mesoscale the maximum values of seabird diversity and abundance correspond to the location of the main fronts. At-sea surveys show a strong curvilinear correlation between seabird abundance and sea surface temperatures. High mean species richness and diversity for whales and seabirds are consistently associated with the southern water mass boundary of the Antarctic Circumpolar Current, the Subtropical Front and the Subantarctic Front; in the case of the Polar Front mean seabird densities are more variable. At small-scales, variation in seabird occurrence has been directly related to the processes at fronts in a limited number of cases. A significant positive relation was found between some plankton feeding species and frontal temperature gradient-phytoplankton variables. Telemetric studies have revealed that several apex predators (penguins, albatrosses, seals) perform long, directed foraging trips either to the Subtropical front or Polar Front, depending on locality. Seabirds with low flight costs, such as albatrosses, are able to reach fronts at long distances from colonies, showing variable foraging strategies as a function of the distances involved. Diving birds such as King penguins, that travel at a higher cost and lower speed, rely on the predictable spatial distribution of mesopelagic fish found close to the Polar Front. They may use the currents associated with eddies as oceanographic cues in the active search for frontal zones. Once in these areas they dive preferentially in and below the depth of the thermocline where catches per unit effort are high. Elephant seals concentrate foraging activity principally inside or at the boundary of cyclonic eddies. These mesoscale features appear to offer exceptional productivity favourable for foraging by various diving top predators. The connection between biophysical parameters at fronts and predators is likely to be made through biological enhancement. Top predators appear to forage at locations where prey are advected by physical processes and others where prey are produced locally. Long-term research on at-sea distributions and demographic parameters of top predators are essential to assess the consequences of potential shift in front distributions in relation to global warming. Such environmental changes would add to the impact of fish extraction by the industrial fisheries on the southern food webs.
	Programme	109; 394
	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	0924-7963	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number	IPEV @ Thierry.Lemaire @			Serial	6049
Permanent link to this record



	Author	Díaz A, Féral J-P, David B, Saucède T, Poulin E,
	Title	Evolutionary pathways among shallow and deep-sea echinoids of the genus Sterechinus in the Southern Ocean			Type	Journal Article
	Year	2011	Publication	Deep Sea Research Part II: Topical Studies in Oceanography	Abbreviated Journal	Deep Sea Res. Part II Top. Stud. Oceanogr.
	Volume	58	Issue	12	Pages	205-211
	Keywords	Sea urchins, Coastal zone, Deep water, Phylogeny, Biogeography, Evolutionary patterns, COI,
	Abstract	Antarctica is structured by a narrow and deep continental shelf that sustains a remarkable number of benthic species. The origin of these species and their affinities with the deep-sea fauna that borders the continent shelf are not clear. To date, two main hypotheses have been considered to account for the evolutionary connection between the faunas: (1) either shallow taxa moved down to deep waters (submergence) or (2) deep-sea taxa colonized the continental shelf (emergence). The regular sea urchin genus Sterechinus is a good model to explore the evolutionary relationships among these faunas because its five nominal species include Antarctic and Subantarctic distributions and different bathymetric ranges. Phylogenetic relationships and divergence times among Sterechinus species were established using the COI mitochondrial gene by assuming a molecular clock hypothesis. The results showed the existence of two genetically distinct main groups. The first corresponds exclusively to the shallow-water Antarctic species S. neumayeri, while the second includes all the other nominal species, either deep or shallow, Antarctic or Subantarctic. Within the latter group, S. dentifer specimens all formed a monophyletic cluster, slightly divergent from all other specimens, which were mixed in a second cluster that included S. agassizi from the continental shelf of Argentina, S. diadema from the Kerguelen Plateau and S. antarcticus from the deep Antarctic shelf. These results suggest that the deeper-water species S. dentifer and S. antarcticus are more closely related to Subantarctic species than to the shallow Antarctic species S. neumayeri. Thus, for this genus, neither the submergence nor emergence scenario explains the relationships between Antarctic and deep-sea benthos. At least in the Weddell quadrant, the observed genetic pattern suggests an initial separation between Antarctic and Subantarctic shallow species, and a much later colonization of deep water from the Subantarctic region, probably promoted by the geomorphology of the Scotia Arc.
	Programme	1124
	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	0967-0645	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	3715
Permanent link to this record

Select All Deselect All

<< 1 2 3 4 5 6 7 8 9 10 >> [11–20]

Details

Show Record |