French Polar Institute Literature Database -- Query Results

	French Polar Institute Literature Database Home \| Show All \| Simple Search \| Advanced Search	Login Quick Search: Field: contains: ...
	261–270 of 8781 records found matching your query (RSS \| history):

Select All Deselect All

[11–20] << 21 22 23 24 25 26 27 28 29 30 >> [31–40]

List View

Citations

Details

	Records
	Author	Dupont F, Picard G, Royer A, Fily M, Roy A, Langlois A, Champollion N,
	Title	Modeling the Microwave Emission of Bubbly Ice: Applications to Blue Ice and Superimposed Ice in the Antarctic and Arctic			Type	Journal Article
	Year	2014	Publication	IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING	Abbreviated Journal
	Volume	Early Access Online	Issue		Pages
	Keywords	Dense media radiative transfer (DMRT) theory, Ice, microwave, Microwave FET integrated circuits, Microwave integrated circuits, Microwave measurement, Microwave radiometry, modeling, remote sensing, Snow, superimposed ice, Temperature measurement,
	Abstract
	Programme	1073
	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	0196-2892	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	4248
Permanent link to this record



	Author	Ricaud P, Carminati F, Attié J-L, Courcoux Y, Rose T, Genthon C, Pellegrini A, Tremblin P, August T,
	Title	Quality Assessment of the First Measurements of Tropospheric Water Vapor and Temperature by the HAMSTRAD Radiometer Over Concordia Station, Antarctica			Type	Journal Article
	Year	2013	Publication	Geoscience and Remote Sensing, IEEE Transactions on	Abbreviated Journal	0196-2892
	Volume	PP	Issue	99	Pages	1-23
	Keywords	Extraterrestrial measurements, Instruments, Microwave radiometry, Ocean temperature, Temperature measurement, Terrestrial atmosphere, Water, Antarctica, atmospheric measurements, humidity measurements, least squares methods, microwave measurements, microwave radiometry, temperature measurements, time series analysis,
	Abstract	The HAMSTRAD microwave instrument operates at 60 and 183 GHz and measures temperature and water vapor, respectively, from 0- to 10-km altitude with a time resolution of 7 min. The radiometer has been successfully deployed at Dome C (Concordia Station), Antarctica ($75^{circ}06^{prime} hbox{S}$, $123^{circ}21^{prime} hbox{E}$, 3233 m amsl) during the first summertime campaign for 12 days in January–February 2009. The radiometer has been continuously running since January 2010, hosted within a dedicated shelter. We have used the very first set of HAMSTRAD data, recorded when the instrument was outdoors, to assess its potential to sound the troposphere over Dome C, from the planetary boundary layer (PBL) up to the tropopause ($sim$6 km above surface, $sim$9 km amsl). We have compared the HAMSTRAD measurements to several sets of measurements performed at the Dome-C station or in its vicinity: meteorological radiosondes, in situ PT100 and Humicap sondes along the vertical extent of a 45-m tower, meteorological sensor attached to the HAMSTRAD instrument, and the spaceborne Infrared Atmospheric Sounding Interferometer (IASI) instrument onboard the EUMETSAT MetOp-A satellite in polar orbit. The variability of integrated water vapor (IWV) observed by HAMSTRAD with extremely low values of 0.5 $hbox{kg} cdot hbox{m}^{-2}$ was also measured by the radiosondes (very high HAMSTRAD versus radiosonde correlation of 0.98), whereas IASI cloud-free measurements did not reproduce well the HAMSTRAD IWV variation (weak HAMSTRAD versus IASI correlation of 0.58). The measurements of absolute humidity $(hbox{H}{2}hbox{O})$ from HAMSTRAD at Dome C cover a large vertical extent from the surface to about 6 km above surface with a high sensitivity in the free troposphere. The strong diurnal v- riation of $hbox{H}{2}hbox{O}$ observed by the in situ sensors in the PBL is not well detected by the radiometer. In the free troposphere, the HAMSTRAD versus radiosonde $hbox{H}_{2}hbox{O}$ correlation can reach 0.8–0.9. Around the tropopause, HAMSTRAD shows the same variability as IASI and radiosondes but with a dry bias of 0.01 $hbox{g} cdot hbox{m}^{-3}$. HAMSTRAD tends to show a wetter atmosphere by 0.1–0.3 $hbox{g} cdot hbox{m}^{-3}$ compared with radiosondes from the surface to $sim$2-km altitude and a drier atmosphere above by $sim!! hbox{0.1} hbox{g} cdot hbox{m}^{-3}$. The sensitivity of the temperature profiles from HAMSTRAD is very high in the PBL and in the free troposphere but degrades around the tropopause. The strong diurnal signal measured above the surface by HAMSTRAD (3–6 K) is consistent with all the other in situ data sets. The temporal evolution over the 12-day period in the PBL is also consistent with all other data sets (radiosondes, IASI, in situ sondes, and meteorological sensors). In the free troposphere and around the tropopause, the HAMSTRAD temporal evolution is consistent with that observed by radiosondes and IASI, although a cold bias exists compared with IASI and radiosondes around the tropopause. For heights less than 4 km above surface, HAMSTRAD correlates very well with radiosondes and in situ sensors (correlation better than 0.8) but less well with IASI (0.4). Below the tropopause, the IASI and HAMSTRAD correlation reaches 0.9, whereas above the tropopause, the correlation of IASI and radiosondes with HAMSTRAD is rather low ($<$ 0.5). Throughout the 12-day period (except on January 23), in the lowermost troposphere for heights less than 500 m above surface, the HAMSTR
	Programme	910,1013
	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	0196-2892	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	660
Permanent link to this record



	Author	RICAUD Philippe, GABARD Benjamin, DERRIEN Sol, CHABOUREAU Jean-Pierre, ROSE Thomas, MOMBAUER Andreas, CZEKALA Harald,
	Title	HAMSTRAD-Tropo, A 183-GHz Radiometer Dedicated to Sound Tropospheric Water Vapor Over Concordia Station, Antarctica			Type	Journal Article
	Year	2010	Publication	IEEE transactions on geoscience and remote sensing	Abbreviated Journal
	Volume	48	Issue	3	Pages	16
	Keywords	Atmospheric measurements, humidity measurement, microwave measurements, microwave radiometry, Europe, Europe, Western Europe, Europe Ouest, polar regions, R, France, France, Antarctica, Antarctique, radiometry, Radiom, atmosphere, Atmosph, models, Mod, sounding, Sondage, humidity, Humidit, accuracy, Pr, temperature, Temp, oxygen, Oxyg, technology, Technologie, domes, Dome, programs, Programme, microwaves, Hyperfr, water vapor, Vapeur eau,
	Abstract	The H[2]O Antarctica Microwave Stratospheric and Tropospheric Radiometers (HAMSTRAD) program aims to develop two ground-based microwave radiometers to sound tropospheric and stratospheric water vapor (H[2]O) above Dome C (Concordia Station), Antarctica (75°06'S, 123°21'E, 3233 m asml), an extremely cold and dry environment, over decades. By using state-of-the-art technology, the HAMSTRAD-Tropo radiometer uses spectral information in the domains 51-59 GHz (oxygen line) and 169-197 GHz (water vapor line) to derive accurate tropospheric profiles of temperature (with accuracy ranging from 1 to 2 K) and low absolute humidity (with accuracy ranging from 0.02 to 0.05 g · m[-3]), together with integrated water vapor (with accuracy of about 0.008 kg · m[-2]) and liquid water path. Prior to its installation at Dome C in January 2009, the fully automated radiometer has been deployed at the Pic du Midi (PdM, 42°56'N, 0°08'E, 2877 m asml, France) in February 2008 and was in operation for five months. Preliminary comparisons with radio soundings particularly launched in the vicinity of PdM in February 2008 and the outputs from the mesoscale MESO-NH model show a great consistency to within 0.2-0.3 g · m[-3] between all absolute humidity data sets whatever the atmosphere considered (extremely dry or wet).
	Programme	910
	Campaign
	Address
	Corporate Author				Thesis	Bachelor's thesis
	Publisher	Institute of Electrical and Electronics Engineers	Place of Publication	New York, NY, ETATS-UNIS	Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0196-2892	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	50
Permanent link to this record



	Author	Fourati H, Manamanni N, Afilal L, Handrich Y,
	Title	A rigid body attitude estimation for Bio-logging application: A quaternion-based nonlinear filter approach			Type	Conference - International - Article with Reading Comitee
	Year	2009	Publication	2009 IEEE/RSJ International Conference on Intelligent Robots and Systems	Abbreviated Journal
	Volume		Issue		Pages	558 -563
	Keywords
	Abstract	Bio-logging is a new interdisciplinary research area at the intersection of animal behavior and bioengineering. It involves several applications such as determination of specific parameters (attitude, acceleration, and position) via a new generation of mechatronic systems. The aim of this paper concerns the animal motion estimation problem using low-cost sensors fusion. A quaternion-based nonlinear observer for the tracking of rigid body attitude (orientation) and heading using measurements provided from low cost inertial and magnetic sensors is presented. The algorithm combines low-frequency, 3-axis accelerometer and 3-axis magnetometer, data with high frequency 3-axis gyroscope measurement. Then, to increase the performance and reduce the computational requirements, we exploit the sensor readings directly in the designed observer. Using the estimated attitude, the linear acceleration is then derived. This latter will be used in the future to evaluate the animal energy index and its mechanical work. Finally, some experimental results, using the measurements provided by an inertial sensor put on dog are given to illustrate the efficiency of the proposed algorithm.
	Programme	394
	Campaign
	Address
	Corporate Author				Thesis	Bachelor's thesis
	Publisher	IEEE	Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	978-1-4244-3803-7	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	944
Permanent link to this record



	Author	Van Petegem, F.,; Collins, T.,; Meuwis, M.-A.,; Gerday, C.,; Feller, G.,; Van Beeumen, J.,
	Title	Crystallization and preliminary X-ray analysis of a xylanase from the psychrophile Pseudoalteromonas haloplanktis			Type	Journal Article
	Year	2002	Publication	Acta crystallographica section d-biological crystallography	Abbreviated Journal	Acta Crystallogr. D Biol. Crystallogr.
	Volume	58	Issue	9	Pages	1494-1496
	Keywords	psychrophiles; cold-adapted enzyme; glycosyl hydrolases
	Abstract	The 46 kDa xylanase from the Antarctic microorganism Pseudoalteromonas haloplanktis is an enzyme that efficiently catalyzes reactions at low temperatures. Here, the crystallization of both the native protein and the SeMet-substituted enzyme and data collection from both crystals using synchrotron radiation are described. The native data showed that the crystals diffract to 1.3 A resolution and belong to space group P212121, with unit-cell parameters a = 50.87, b = 90.51, c = 97.23 A. SAD data collected at the peak of the selenium absorption edge proved to be sufficient to determine the heavy-atom configuration and to obtain electron density of good quality.
	Programme	193
	Campaign
	Address
	Corporate Author				Thesis
	Publisher	International Union of Crystallography	Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0907-4449	ISBN		Medium
	Area		Expedition		Conference
	Notes	doi:10.1107/S0907444902011666			Approved	yes
	Call Number	IPEV @ Thierry.Lemaire @			Serial	5579
Permanent link to this record



	Author	Christophe Barbraud, Karine Delord, Akiko Kato, Paco Bustamante, Yves Cherel
	Title	Sexual segregation in a highly pagophilic and sexually dimorphic marine predator			Type	Journal
	Year	2019	Publication	bioRxiv	Abbreviated Journal
	Volume		Issue		Pages	472431
	Keywords
	Abstract	Sexual segregation is common in many species and has been attributed to intra-specific competition, sex-specific differences in foraging efficiency or in activity budgets and habitat choice. However, very few studies have simultaneously quantified sex-specific foraging strategies, at sea distribution, habitat use, and trophic ecology. Moreover, these studies come from low latitude areas reflecting a lack of evidence for polar species. We investigated sexual segregation in snow petrels Pagodroma nivea and combined movement, foraging trip efficiency, stable isotope and oceanographic data to test whether sexual segregation results from sex-specific habitat use. Breeding birds foraging in the Dumont d’Urville sea, Antarctica, were tracked during incubation. Some similarities between males and females foraging characteristics did not support the sexual segregation hypothesis. Indeed, space-use sharing and utilization distribution, δ¹³C values and foraging trip performances (trip duration, length, speed and directions, mass gain, proportion mass gain) were similar between males and females.. However, there was support for sexual segregation in foraging characteristics linked to foraging habitats. Females foraged less than males in areas with higher sea ice concentration (SIC >70%) and had lower δ¹⁵N values in plasma, blood cells and feathers. Foraging efficiency (proportionate daily mass gain while foraging), was greater for females than for males, and was greater for larger females with deeper bills. Females were more efficient than males during short (<2 days) foraging trips, and for females, but not for males, mass gain, proportion mass gain and body condition at return from a foraging trip were positively correlated to SIC of the foraging areas. Together, these results suggest an absence of sexual segregation at large spatial scales in snow petrels during incubation, but strongly support habitat segregation between high (>70%) more profitable SIC (males) and low SIC areas (females), probably driven by intraspecific competition. Therefore, male and female snow petrels segregate at small spatial scales mainly determined by habitat (SIC) characteristics.
	Programme	109
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7635
Permanent link to this record



	Author	Fernando Arce, Mark A. Hindell, Clive R. McMahon, Simon J. Wotherspoon, Christophe Guinet, Robert G. Harcourt, Sophie Bestley
	Title	Elephant seal foraging success is enhanced in Antarctic coastal polynyas			Type	Journal
	Year	2022	Publication	Proceedings of the Royal Society B: Biological Sciences	Abbreviated Journal
	Volume	289	Issue	1967	Pages	20212452
	Keywords	body condition drift rates foraging behaviour Mirounga leonina post-polynyas Southern Ocean
	Abstract	Antarctic polynyas are persistent open water areas which enable early and large seasonal phytoplankton blooms. This high primary productivity, boosted by iron supply from coastal glaciers, attracts organisms from all trophic levels to form a rich and diverse community. How the ecological benefit of polynya productivity is translated to the highest trophic levels remains poorly resolved. We studied 119 southern elephant seals feeding over the Antarctic shelf and demonstrated that: (i) 96% of seals foraging here used polynyas, with individuals spending on average 62% of their time there; (ii) the seals exhibited more area-restricted search behaviour when in polynyas; and (iii) these seals gained more energy (indicated by increased buoyancy from greater fat stores) when inside polynyas. This higher-quality foraging existed even when ice was not present in the study area, indicating that these are important and predictable foraging grounds year-round. Despite these energetic advantages from using polynyas, not all the seals used them extensively. Factors other than food supply may influence an individual's choice in their use of feeding grounds, such as exposure to predation or the probability of being able to return to distant sub-Antarctic breeding sites.
	Programme	109,1201
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7983
Permanent link to this record



	Author	Julie Mestre, Matthieu Authier, Yves Cherel, Rob Harcourt, Clive R. McMahon, Mark A. Hindell, Jean-Benoît Charrassin, Christophe Guinet
	Title	Decadal changes in blood δ13C values, at-sea distribution, and weaning mass of southern elephant seals from Kerguelen Islands			Type	Journal
	Year	2020	Publication	Proceedings of the Royal Society B: Biological Sciences	Abbreviated Journal
	Volume	287	Issue	1933	Pages	20201544
	Keywords	bio-logging decadal change foraging habitat Indian sector of the Southern Ocean population strategies stable isotopes
	Abstract	Changes in the foraging environment and at-sea distribution of southern elephant seals from Kerguelen Islands were investigated over a decade (2004–2018) using tracking, weaning mass, and blood δ13C values. Females showed either a sub-Antarctic or an Antarctic foraging strategy, and no significant shift in their at-sea distribution was detected between 2004 and 2017. The proportion of females foraging in sub-Antarctic versus Antarctic habitats did not change over the 2006–2018 period. Pup weaning mass varied according to the foraging habitat of their mothers. The weaning mass of sub-Antarctic foraging mothers' pups decreased by 11.7 kg over the study period, but they were on average 5.8 kg heavier than pups from Antarctic foraging mothers. Pup blood δ13C values decreased by 1.1‰ over the study period regardless of their sex and the presumed foraging habitat of their mothers. Together, these results suggest an ecological change is occurring within the Indian sector of the Southern Ocean with possible consequences on the foraging performance of southern elephant seals. We hypothesize that this shift in δ13C is related to a change in primary production and/or in the composition of phytoplankton communities, but this requires further multidisciplinary investigations.
	Programme	109,1201
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8006
Permanent link to this record



	Author	Riotte-Lambert Louise, Weimerskirch Henri,
	Title	Do naive juvenile seabirds forage differently from adults?			Type	Journal Article
	Year	2013	Publication	PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES	Abbreviated Journal	Proc. Biol. Sci.
	Volume	280	Issue	1768	Pages	20131434
	Keywords	albatross, immaturity, learning, movement, telemetry,
	Abstract	Foraging skills of young individuals are assumed to be inferior to those of adults. The reduced efficiency of naive individuals may be the primary cause of the high juvenile mortality and explain the deferment of maturity in long-lived species. However, the study of juvenile and immature foraging behaviour has been limited so far. We used satellite telemetry to compare the foraging movements of juveniles, immatures and breeding adult wandering albatrosses Diomedea exulans, a species where foraging success is positively influenced by the distance covered daily. We showed that juveniles are able to use favourable winds as soon as the first month of independence, but cover shorter distances daily and spend more time sitting on water than adults during the first two months after fledging. These reduced movement capacities do not seem to be the cause of higher juvenile mortality. Moreover, juveniles almost never restrict their movement to specific areas, as adults and immatures frequently do over shelf edges or oceanic zones, which suggest that the location of appropriate areas is learned through experience. Immatures and adults have equivalent movement capacities, but when they are central place foragers, i.e. when adults breed or immatures come to the colony to display and pair, immatures make shorter trips than adults. The long duration of immaturity in this species seems to be related to a long period of learning to integrate the foraging constraints associated with reproduction and central place foraging. Our results indicate that foraging behaviour of young albatrosses is partly innate and partly learned progressively over immaturity. The first months of learning appear critical in terms of survival, whereas the long period of immaturity is necessary for young birds to attain the skills necessary for efficient breeding without fitness costs.
	Programme	109
	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	0962-8452	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	4323
Permanent link to this record



	Author	Bestley Sophie, Jonsen Ian D, Hindell Mark A, Guinet Christophe, Charrassin Jean-Benoît,
	Title	Integrative modelling of animal movement: incorporating in situ habitat and behavioural information for a migratory marine predator			Type	Journal Article
	Year	2012	Publication	PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON	Abbreviated Journal
	Volume	280	Issue		Pages	20122262
	Keywords	animal telemetry, foraging behaviour, individual movement, oceanographic drivers of movement, spatial ecology, state-space model,
	Abstract
	Programme	109
	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	0962-8452	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	4436
Permanent link to this record

Select All Deselect All

[11–20] << 21 22 23 24 25 26 27 28 29 30 >> [31–40]

Details

Show Record |