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Juliana A. Vianna, Flávia A. N. Fernandes, María José Frugone, Henrique V. Figueiró, Luis R. Pertierra, Daly Noll, Ke Bi, Cynthia Y. Wang-Claypool, Andrew Lowther, Patricia Parker, Celine Le Bohec, Francesco Bonadonna, Barbara Wienecke, Pierre Pistorius, Antje Steinfurth, Christopher P. Burridge, Gisele P. M. Dantas, Elie Poulin, W. Brian Simison, Jim Henderson, Eduardo Eizirik, Mariana F. Nery, Rauri C. K. Bowie |
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Title |
Genome-wide analyses reveal drivers of penguin diversification |
Type |
Journal |
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Year  |
2020 |
Publication |
Proceedings of the National Academy of Sciences |
Abbreviated Journal |
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Volume |
117 |
Issue |
36 |
Pages |
22281-22292 |
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Keywords |
ancestral distribution ancestral niche Antarctica genome penguin |
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Abstract |
Penguins are the only extant family of flightless diving birds. They currently comprise at least 18 species, distributed from polar to tropical environments in the Southern Hemisphere. The history of their diversification and adaptation to these diverse environments remains controversial. We used 22 new genomes from 18 penguin species to reconstruct the order, timing, and location of their diversification, to track changes in their thermal niches through time, and to test for associated adaptation across the genome. Our results indicate that the penguin crown-group originated during the Miocene in New Zealand and Australia, not in Antarctica as previously thought, and that Aptenodytes is the sister group to all other extant penguin species. We show that lineage diversification in penguins was largely driven by changing climatic conditions and by the opening of the Drake Passage and associated intensification of the Antarctic Circumpolar Current (ACC). Penguin species have introgressed throughout much of their evolutionary history, following the direction of the ACC, which might have promoted dispersal and admixture. Changes in thermal niches were accompanied by adaptations in genes that govern thermoregulation and oxygen metabolism. Estimates of ancestral effective population sizes (Ne) confirm that penguins are sensitive to climate shifts, as represented by three different demographic trajectories in deeper time, the most common (in 11 of 18 penguin species) being an increased Ne between 40 and 70 kya, followed by a precipitous decline during the Last Glacial Maximum. The latter effect is most likely a consequence of the overall decline in marine productivity following the last glaciation. |
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137,354 |
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0027-8424, 1091-6490 |
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yes |
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7780 |
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Mario Lebrato, Dieter Garbe-Schönberg, Marius N. Müller, Sonia Blanco-Ameijeiras, Richard A. Feely, Laura Lorenzoni, Juan-Carlos Molinero, Karen Bremer, Daniel O. B. Jones, Debora Iglesias-Rodriguez, Dana Greeley, Miles D. Lamare, Aurelien Paulmier, Michelle Graco, Joan Cartes, Joana Barcelos e Ramos, Ana de Lara, Ricardo Sanchez-Leal, Paz Jimenez, Flavio E. Paparazzo, Susan E. Hartman, Ulrike Westernströer, Marie Küter, Roberto Benavides, Armindo F. da Silva, Steven Bell, Chris Payne, Solveig Olafsdottir, Kelly Robinson, Liisa M. Jantunen, Alexander Korablev, Richard J. Webster, Elizabeth M. Jones, Olivier Gilg, Pascal Bailly du Bois, Jacek Beldowski, Carin Ashjian, Nejib D. Yahia, Benjamin Twining, Xue-Gang Chen, Li-Chun Tseng, Jiang-Shiou Hwang, Hans-Uwe Dahms, Andreas Oschlies |
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Title |
Global variability in seawater Mg:Ca and Sr:Ca ratios in the modern ocean |
Type |
Book Chapter |
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Year |
2020 |
Publication |
Proceedings of the National Academy of Sciences |
Abbreviated Journal |
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Volume |
117 |
Issue |
36 |
Pages |
22281-22292 |
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Keywords |
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Abstract |
Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth–ocean–atmosphere dynamic exchange of elements. The ratios’ dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally. High variability was found in open-ocean upwelling and polar regions, shelves/neritic and river-influenced areas, where seawater Mg:Ca and Sr:Ca ratios range from ∼4.40 to 6.40 mmol:mol and ∼6.95 to 9.80 mmol:mol, respectively. Open-ocean seawater Mg:Ca is semiconservative (∼4.90 to 5.30 mol:mol), while Sr:Ca is more variable and nonconservative (∼7.70 to 8.80 mmol:mol); both ratios are nonconservative in coastal seas. Further, the Ca, Mg, and Sr elemental fluxes are connected to large total alkalinity deviations from International Association for the Physical Sciences of the Oceans (IAPSO) standard values. Because there is significant modern seawater Mg:Ca and Sr:Ca ratios variability across marine environments we cannot absolutely assume that fossil archives using taxa-specific proxies reflect true global seawater chemistry but rather taxa- and process-specific ecosystem variations, reflecting regional conditions. This variability could reconcile secular seawater Mg:Ca and Sr:Ca ratio reconstructions using different taxa and techniques by assuming an error of 1 to 1.50 mol:mol, and 1 to 1.90 mmol:mol, respectively. The modern ratios’ variability is similar to the reconstructed rise over 20 Ma (Neogene Period), nurturing the question of seminonconservative behavior of Ca, Mg, and Sr over modern Earth geological history with an overlooked environmental effect. |
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136 |
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0027-8424, 1091-6490 |
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yes |
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7781 |
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Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Jean-Christopher Lambert, Henk J. Eskes, Kai-Uwe Eichmann, Ann Mari Fjæraa, José Granville, Sander Niemeijer, Alexander Cede, Martin Tiefengraber, François Hendrick, Andrea Pazmiño, Alkiviadis Bais, Ariane Bazureau, K. Folkert Boersma, Kristof Bognar, Angelika Dehn, Sebastian Donner, Aleksandr Elokhov, Manuel Gebetsberger, Florence Goutail, Michel Grutter de la Mora, Aleksandr Gruzdev, Myrto Gratsea, Georg H. Hansen, Hitoshi Irie, Nis Jepsen, Yugo Kanaya, Dimitris Karagkiozidis, Rigel Kivi, Karin Kreher, Pieternel F. Levelt, Cheng Liu, Moritz Müller, Monica Navarro Comas, Ankie J. M. Piters, Jean-Pierre Pommereau, Thierry Portafaix, Olga Puentedura, Richard Querel, Julia Remmers, Andreas Richter, John Rimmer, Claudia Rivera Cárdenas, Lidia Saavedra de Miguel, Valery P. Sinyakov, Kimberley Strong, Michel Van Roozendael, J. Pepijn Veefkind, Thomas Wagner, Folkard Wittrock, Margarita Yela González, Claus Zehner |
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Title |
Ground-based validation of the Copernicus Sentinel-5p TROPOMI NO2 measurements with the NDACC ZSL-DOAS, MAX-DOAS and Pandonia global networks |
Type |
Journal |
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Year |
2020 |
Publication |
Atmospheric Measurement Techniques Discussions |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-40 |
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Abstract |
This Paper Reports On Consolidated Ground-based Validation Results Of The Atmospheric No2 Data Produced Operationally Since April 2018 By The Tropomi Instrument On Board Of The Esa/eu Copernicus Sentinel-5 Precursor (S5p) Satellite. Tropospheric, Stratospheric, And Total No2 Column Data From S5p Are Compared To Correlative Measurements Collected From, Respectively, 19 Multi-axis Doas (Max-doas), 26 Ndacc Zenith-scattered-light Doas (Zsl-doas), And 25 Pgn/pandora Instruments Distributed Globally. The Validation Methodology Gives Special Care To Minimizing Mismatch Errors Due To Imperfect Spatio-temporal Co-location Of The Satellite And Correlative Data, E.g., By Using Tailored Observation Operators To Account For Differences In Smoothing And In Sampling Of Atmospheric Structures And Variability, And Photochemical Modelling To Reduce Diurnal Cycle Effects. Compared To The Ground-based Measurements, S5p Data Show, On An Average: (I) A Negative Bias For The Tropospheric Column Data, Of Typically −23 To −37 % In Clean To Slightly Polluted Conditions, But Reaching Values As High As −51 % Over Highly Polluted Areas; (Ii) A Slight Negative Bias For The Stratospheric Column Data, Of About −0.2 Pmolec/cm2, I.e. Approx. −2 % In Summer To −15 % In Winter; And (Iii) A Bias Ranging From Zero To −50 % For The Total Column Data, Found To Depend On The Amplitude Of The Total No2 Column, With Small To Slightly Positive Bias Values For Columns Below 6 Pmolec/cm2 And Negative Values Above. The Dispersion Between S5p And Correlative Measurements Contains Mostly Random Components, Which Remain Within Mission Requirements For The Stratospheric Column Data (0.5 Pmolec/cm2), But Exceed Those For The Tropospheric Column Data (0.7 Pmolec/cm2). While A Part Of The Biases And Dispersion May Be Due To Representativeness Differences, It Is Known That Errors In The S5p Tropospheric Columns Exist Due To Shortcomings In The (Horizontally Coarse) A-priori Profile Representation In The Tm5-mp Chemistry Transport Model Used In The S5p Retrieval, And To A Lesser Extent, To The Treatment Of Cloud Effects. Although Considerable Differences (Up To 2 Pmolec/cm2 And More) Are Observed At Single Ground-pixel Level, The Near-real-time (Nrti) And Off-line (Offl) Versions Of The S5p No2 Operational Data Processor Provide Similar No2 Column Values And Validation Results When Globally Averaged, With The Nrti Values Being On Average 0.79 % Larger Than The Offl Values. |
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209 |
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Bachelor's thesis |
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ISSN |
1867-1381 |
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yes |
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7782 |
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Author |
Romanova, L. G., Pokatilova, N. V., Balter, V., &Amp; Crubezy, E. |
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Title |
Mezhdisciplinarnyj podhod v izuchenii pitanija jakutov s XVII po XIX v. [Archaeological and biological approaches in the study of the Yakut diet in the 17th and 19th/20th centuries] (In Russian) |
Type |
Journal |
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Year |
2020 |
Publication |
Yakut medical journal |
Abbreviated Journal |
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Volume |
1 |
Issue |
69 |
Pages |
73-76 |
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Programme |
1038 |
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Bachelor's thesis |
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yes |
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7784 |
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Author |
Vincent Zvénigorosky, Sylvie Duchesne, Liubomira Romanova, Patrice Gérard, Christiane Petit, Michel Petit, Anatoly Alexeev, Olga Melnichuk, Angéla Gonzalez, Jean-Luc Fausser, Aisen Solovyev, Georgii Romanov, Nikolay Barashkov, Sardana Fedorova, Bertrand Ludes, Eric Crubézy, Christine Keyser |
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Title |
The genetic legacy of legendary and historical Siberian chieftains |
Type |
Journal |
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Year |
2020 |
Publication |
Communications Biology |
Abbreviated Journal |
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Volume |
3 |
Issue |
1 |
Pages |
1-9 |
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Keywords |
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Abstract |
Seventeen years of archaeological and anthropological expeditions in North-Eastern Siberia (in the Sakha Republic, Yakutia) have permitted the genetic analysis of 150 ancient (15th-19th century) and 510 modern individuals. Almost all males were successfully analysed (Y-STR) and this allowed us to identify paternal lineages and their geographical expansion through time. This genetic data was confronted with mythological, historical and material evidence to establish the sequence of events that built the modern Yakut genetic diversity. We show that the ancient Yakuts recovered from this large collection of graves are not representative of an ancient population. Uncommonly, we were also able to demonstrate that the funerary preference observed here involved three specific male lineages, especially in the 18th century. Moreover, this dominance was likely caused by the Russian conquest of Siberia which allowed some male clans to rise to new levels of power. Finally, we give indications that some mythical and historical figures might have been the actors of those genetic changes. These results help us reconsider the genetic dynamics of colonization in some regions, question the distinction between fact and myth in national histories and provide a rare insight into a funerary ensemble by revealing the biased process of its composition. |
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Programme |
1038 |
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Bachelor's thesis |
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ISSN |
2399-3642 |
ISBN |
2399-3642 |
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yes |
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Serial |
7790 |
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Author |
Chuxian Li, Jeroen E. Sonke, Gaël Le Roux, Natalia Piotrowska, Nathalie Van der Putten, Stephen J. Roberts, Tim Daley, Emma Rice, Roland Gehrels, Maxime Enrico, Dmitri Mauquoy, Thomas P. Roland, François De Vleeschouwer |
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Title |
Unequal Anthropogenic Enrichment of Mercury in Earth’s Northern and Southern Hemispheres |
Type |
Journal |
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Year |
2020 |
Publication |
ACS Earth and Space Chemistry |
Abbreviated Journal |
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Volume |
4 |
Issue |
11 |
Pages |
2073-2081 |
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Abstract |
Remote Northern Hemisphere (NH) and Southern Hemisphere (SH) lake sediment and peat records of mercury (Hg) deposition have shown a ×3 to ×5 Hg enrichment since pre-industrial times (<1880 AD), leading to the perception that global atmospheric Hg enrichment is moderate and uniform across the hemispheres. Anthropogenic Hg emissions in the NH are, however, approximately 4 times higher than those in the SH. Here, we reconstruct atmospheric Hg deposition in four remote SH peatlands and review sediment and peat Hg records from both hemispheres. We observe a ×4 all-time enrichment in SH Hg deposition from pre-anthropogenic (<1450 AD) to the late 20th-century periods, which is lower than the large ×16 all-time enrichment in NH Hg deposition. We attribute this difference to lower anthropogenic Hg emissions in the SH, and higher natural atmospheric SH Hg concentrations, supported by ×2 higher natural background Hg accumulation in SH peat records. We suggest that the higher SH natural atmospheric Hg deposition reflects the SH land–ocean distribution, and is driven by important SH marine Hg emissions. Our findings indicate that atmospheric Hg background levels and anthropogenic enrichment in both hemispheres are different and should be taken into account in international Hg assessments and environmental policy. |
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Programme |
1065,1133 |
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Bachelor's thesis |
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yes |
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Serial |
7791 |
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Author |
Lorène Julia Marchand, Michèle Tarayre, Thomas Dorey, Yann Rantier, Françoise Hennion |
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Title |
Morphological variability of cushion plant Lyallia kerguelensis (Caryophyllales) in relation to environmental conditions and geography in the Kerguelen Islands: implications for cushion necrosis and climate change |
Type |
Journal |
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Year |
2020 |
Publication |
Polar Biology |
Abbreviated Journal |
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Volume |
44 |
Issue |
1 |
Pages |
17-30 |
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Abstract |
In recent decades, climate change has been faster in various parts of the world. Within species, to counter rapid climate changes shift of geographical area, individuals’ plastic responses or populations’ genetic adaptation might occur. The sub-Antarctic islands are subject to one of the most rapid climate changes on earth, with already visible impacts on native vegetation. Such might be the case of Lyallia kerguelensis a cushion plant strictly endemic to the Kerguelen Islands. In L. kerguelensis, necrotic parts were observed in cushions these last decades and possibly related to water stress. We analysed morphological variability of L. kerguelensis, including necrosis extent, across 19 populations spanning a wide range of environments across the Kerguelen Islands. Inter-population variations in the cushion surface area, shape and compactness were well explained by topography, degree of wind exposure, slope aspect, proportions of coarse sand and bare soil, and geographical distance between populations. All these variables are related to wind intensity and water availability. Moreover, in cushions with less than 10% necrosis in surface area, necrosis extent was positively correlated to soil sodium. Sodium availability might reduce the plant’s capacity for osmotic adjustment in face of other abiotic stresses, such as water stress. We conclude that cushion morphology may have the capacity to adjust to environmental variation, including aspects of climate change, but that cushion necrosis may be accelerated in the driest and most saline environments. |
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Programme |
1116 |
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Bachelor's thesis |
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ISSN |
1432-2056 |
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yes |
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7793 |
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Author |
Korbinian Sager, Christian Boehm, Laura Ermert, Lion Krischer, Andreas Fichtner |
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Title |
Global-Scale Full-Waveform Ambient Noise Inversion |
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Journal |
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Year |
2020 |
Publication |
Journal of Geophysical Research: Solid Earth |
Abbreviated Journal |
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Volume |
125 |
Issue |
4 |
Pages |
e2019JB018644 |
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Keywords |
computational seismology full-waveform inversion global tomography interferometry seismic noise |
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Abstract |
We present the first application of full-waveform ambient noise inversion to observed correlation functions that jointly constrains 3-D Earth structure and heterogeneous noise sources. For this, we model and interpret ambient noise correlations as recordings of correlation wavefields, which completely eliminates the limiting assumptions of Green's function retrieval, such as equipartitioning and homogeneous random noise sources. Our method accounts for seismic wave propagation physics in 3-D heterogeneous and attenuating media and also for the heterogeneous and nonstationary nature of the ambient noise field. Designed as a proof of concept, the study considers long periods from 100 to 300 s, thus focusing on the Earth's hum. Treating correlations as self-consistent observables allows us to make separate measurements on the causal and acausal branches of correlation functions, without any need to choose one of them or form the average. We validate our approach by assessing the quality of the obtained models and by comparing them to previous studies. This work is a step toward the establishment of full-waveform ambient noise inversion as a tomographic technique with the goal to go beyond ambient noise tomography based on Green's function retrieval. |
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133 |
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ISSN |
2169-9356 |
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yes |
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Serial |
7794 |
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Author |
F. Pitout, A. Marchaudon, K. J. Trattner, J. Berchem, H. Laakso, C. P. Escoubet |
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Title |
Simultaneous Polar and Cluster Observations in the Northern and Southern Middle-Altitude Polar Cusps Around Equinox |
Type |
Journal |
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Year |
2020 |
Publication |
Journal of Geophysical Research: Space Physics |
Abbreviated Journal |
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Volume |
125 |
Issue |
12 |
Pages |
e2020JA028346 |
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Keywords |
dayside magnetosphere hemispheric asymmetry polar cusp |
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Abstract |
We present an event of simultaneous observations of the northern and southern middle-altitude polar cusps by the Polar spacecraft and Cluster fleet that occurred on 23 September 2004. We examine the possible asymmetries in the fields and plasma parameters, although the proximity of the equinox should limit these asymmetries. Ion sensors reveal two dispersions in both cusps, and data analysis leads to the conclusion that those dispersions are due to pulsed reconnection at a single X-line, which runs along the subsolar magnetopause. While the electromagnetic and particle energy fluxes injected in both cusp are globally very similar, we report significant differences in ion dispersions, width of the low-latitude boundary layer, and peak convection velocities. We ascribe these differences to the dipole tilt that introduces an asymmetry in the magnetosheath flow at the exterior cusps. |
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312 |
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ISSN |
2169-9402 |
ISBN |
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yes |
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Call Number |
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Serial |
6363 |
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Author |
Léo Bosse, Jean Lilensten, Nicolas Gillet, Sylvain Rochat, Alain Delboulbé, Stephane Curaba, Alain Roux, Yves Magnard, Magnar G. Johnsen, Unni-Pia Løvhaug, Pierre-Olivier Amblard, Nicolas Le Bihan, Maxime Nabon, Hanane Marif, Frédérique Auriol, Camille Noûs |
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Title |
On the nightglow polarisation for space weather exploration |
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Year |
2020 |
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Journal of Space Weather and Space Climate |
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10 |
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35 |
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Keywords |
polarisation / aurora |
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Abstract |
We present here observations of the polarisation of four auroral lines in the auroral oval and in the polar cusp using a new ground polarimeter called Petit Cru. Our results confirm the already known polarisation of the red line, and show for the first time that the three other lines observed here (namely 557.7 nm, 391.4 nm and 427.8 nm) are polarised as well up to a few percent. We show that in several circumstances, this polarisation is linked to the local magnetic activity and to the state of the ionosphere through the electron density measured with EISCAT. However, we also show that the contribution of light pollution from nearby cities via scattering can not be ignored and can play an important role in polarisation measurements. This series of observations questions the geophysical origin of the polarisation. It also leaves open its relation to the magnetic field orientation and to the state of both the upper atmosphere and the troposphere. |
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Programme |
1026 |
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ISSN |
2115-7251 |
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Approved |
yes |
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Call Number |
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Serial |
7796 |
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