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Author  |
Niels M. Schmidt, Olivier Gilg, Jon Aars, Rolf A. Ims |
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Title |
Fat, Furry, Flexible, and Functionally Important: Characteristics of Mammals Living in the Arctic |
Type |
Book |
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Year |
2021 |
Publication |
Arctic Ecology |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
357-384 |
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Keywords |
arctic ecosystems Arctic mammals climate change deglaciation food webs homeotherms low mammal species diversity primary production |
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Abstract |
Mammals constitute a group of vertebrates that share a number of unique characteristics,such as nursing their young with milk, and having hair. The pattern of low mammal species diversity in the Arctic probably reflects a combination of mainly two driving factors: first, being homeotherms, mammals require a substantial amount of energy to sustain the various life processes, and the arctic regions are characterized by a very low availability of energy due to short seasons for primary production. Secondly, the occurrence of arctic mammals today reflects the reinvasion of the mammal species into the Arctic as the ecosystems were re-established following the deglaciation. This chapter discusses the characteristics of the arctic mammals, including their unique adaptations to life, and their role as both consumer and food base in the arctic ecosystems. Climate change in the Arctic may also alter the interactions within food webs. |
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1036 |
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978-1-118-84658-2 |
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yes |
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Serial |
8489 |
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Author |
Nicolas Meyer, Loïc Bollache, Matthias Galipaud, Jérôme Moreau, François-Xavier Dechaume-Moncharmont, Eve Afonso, Anders Angerbjörn, Joël Bêty, Glen Brown, Dorothée Ehrich, Vladimir Gilg, Marie-Andrée Giroux, Jannik Hansen, Richard Lanctot, Johannes Lang, Christopher Latty, Nicolas Lecomte, Laura McKinnon, Lisa Kennedy, Jeroen Reneerkens, Sarah Saalfeld, Brigitte Sabard, Niels M. Schmidt, Benoît Sittler, Paul Smith, Aleksander Sokolov, Vasiliy Sokolov, Natalia Sokolova, Rob van Bemmelen, Øystein Varpe, Olivier Gilg |
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Title |
Behavioural responses of breeding arctic sandpipers to ground-surface temperature and primary productivity |
Type |
Journal |
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Year |
2021 |
Publication |
Science of The Total Environment |
Abbreviated Journal |
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Volume |
755 |
Issue |
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Pages |
142485 |
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Keywords |
Environmental conditions Incubation behaviour Incubation recesses Incubation strategy Lag effects NDVI Shorebird |
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Abstract |
Most birds incubate their eggs, which requires time and energy at the expense of other activities. Birds generally have two incubation strategies: biparental where both mates cooperate in incubating eggs, and uniparental where a single parent incubates. In harsh and unpredictable environments, incubation is challenging due to high energetic demands and variable resource availability. We studied the relationships between the incubation behaviour of sandpipers (genus Calidris) and two environmental variables: temperature and a proxy of primary productivity (i.e. NDVI). We investigated how these relationships vary between incubation strategies and across species among strategies. We also studied how the relationship between current temperature and incubation behaviour varies with previous day's temperature. We monitored the incubation behaviour of nine sandpiper species using thermologgers at 15 arctic sites between 2016 and 2019. We also used thermologgers to record the ground surface temperature at conspecific nest sites and extracted NDVI values from a remote sensing product. We found no relationship between either environmental variables and biparental incubation behaviour. Conversely, as ground-surface temperature increased, uniparental species decreased total duration of recesses (TDR) and mean duration of recesses (MDR), but increased number of recesses (NR). Moreover, small species showed stronger relationships with ground-surface temperature than large species. When all uniparental species were combined, an increase in NDVI was correlated with higher mean duration, total duration and number of recesses, but relationships varied widely across species. Finally, some uniparental species showed a lag effect with a higher nest attentiveness after a warm day while more recesses occurred after a cold day than was predicted based on current temperatures. We demonstrate the complex interplay between shorebird incubation strategies, incubation behaviour, and environmental conditions. Understanding how species respond to changes in their environment during incubation helps predict their future reproductive success. |
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1036 |
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ISSN |
0048-9697 |
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yes |
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7553 |
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Author |
Natasha Roy, James Woollett, Najat Bhiry, Isabel Lemus-Lauzon, Ann Delwaide, Dominique Marguerie |
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Title |
Anthropogenic and climate impacts on subarctic forests in the Nain region, Nunatsiavut: Dendroecological and historical approaches |
Type |
Journal |
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Year |
2021 |
Publication |
Écoscience |
Abbreviated Journal |
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Volume |
28 |
Issue |
3-4 |
Pages |
361-376 |
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Keywords |
approches historiques croissance démographique Dendrochronologie Dendrochronology détente de croissance radiale growth release historical approaches Nain Nunatsiavut population growth |
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Abstract |
Several recent dendrochronological, macrofossil and palynological studies have surveyed modern spruce forests at multiple locations in the Nain region of coastal Nunatsiavut (north-central Labrador) in order to reconstruct past forest composition, growth rates, species diversity and harvesting patterns. The present paper synthesizes original and previously collected data to evaluate the extent to which the dynamics of the region’s spruce forests over the past five centuries have been related to anthropogenic impacts. In three key case studies, Picea growth release events demonstrate multiple isolated forest disturbances prior to the late 19th century. In general, these events correspond to the local human settlement history rather than to regional climatic trends, suggesting that ongoing human impacts on the forest extend as far back as the 17th century. Disturbance regimes accelerated by ca 1875 and afterward in all of the study sites. This increase in forest disturbance corresponds to increased demands for wood triggered by socio-economic changes experienced by the region’s Inuit and Settler communities. Ongoing surveys demonstrate the presence of markers of human exploitation of forests throughout the study region, and especially in coastal locations, suggesting that anthropogenic impacts are in fact generalised and not limited to specific areas of recent settlement. |
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1080 |
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ISSN |
1195-6860 |
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yes |
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Serial |
8251 |
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Author |
Najat Bhiry, Dominique Marguerie, Tommy Weetaluktuk, Myosotis Desroches Bourgon, David Aoustin, Pierre M. Desrosiers, Dominique Todisco |
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Title |
Dorset and Thule Inuit occupations of Qikirtajuaq (Smith Island), Nunavik, Canada: a palaeoecological approach |
Type |
Journal |
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Year |
2021 |
Publication |
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Abbreviated Journal |
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Volume |
Boreas |
Issue |
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Pages |
826-843 |
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Abstract |
Qikirtajuaq is a long island facing the Inuit village of Akulivik on the northeastern coast of Hudson Bay (Canada) that is rich in archaeological sites. Kangiakallak-1 (JeGn-2), one of the main sites on this island, is a large multicomponent site that includes Dorset and Thule Inuit winter houses. This study documents the dynamics of palaeoenvironmental conditions in the successive occupations of the Kangiakallak-1 settlement based on plant macrofossils, pollen and non-pollen palynomorph analyses and archaeological research. The data indicate that Dorset inhabitants constructed their dwelling at about 772 cal. a BP. The site was reused by the Thule Inuit a few decades later, starting at about 671 cal. a BP. Thus, Kangiakallak-1 is one of the few sites, at least in Nunavik (northern Quebec, Canada), that were rapidly reoccupied by the Thule Inuit after the departure of the Dorset inhabitants, which indicates a possible overlap between the two cultures in the Akulivik region. The palaeoecological data show that both Dorset and Thule inhabitants left clear footprints at the local scale in the form of several nitrophilous species that became established in and near the houses and persisted over a long period. The deposition of domestic waste (including bone fragments, skin, burnt fat and charcoal fragments) inside the subterranean dwellings fertilized the soil and led to the growth of unique nitrophilous plants. These changes transformed the houses into exceptional floristic refuges. |
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1080 |
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0300-9483 |
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yes |
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8520 |
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Author |
N. Ribeiro, L. Herraiz-Borreguero, S. R. Rintoul, C. R. McMahon, M. Hindell, R. Harcourt, G. Williams |
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Title |
Warm Modified Circumpolar Deep Water Intrusions Drive Ice Shelf Melt and Inhibit Dense Shelf Water Formation in Vincennes Bay, East Antarctica |
Type |
Journal |
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Year |
2021 |
Publication |
Journal of Geophysical Research: Oceans |
Abbreviated Journal |
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Volume |
126 |
Issue |
8 |
Pages |
e2020JC016998 |
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Keywords |
AABW Antarctic Coastal Circulation Antarctic Margins basal melt mCDW intrusions seal CTD |
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Abstract |
Antarctic Bottom Water (AABW) production supplies the deep limb of the global overturning circulation and ventilates the deep ocean. While the Weddell and Ross Seas are recognized as key sites for AABW production, additional sources have been discovered in coastal polynya regions around East Antarctica, most recently at Vincennes Bay. Vincennes Bay, despite encompassing two distinct polynya regions, is considered the weakest source, producing Dense Shelf Water (DSW) only just dense enough to contribute to the lighter density classes of AABW found offshore. Here we provide the first detailed oceanographic observations of the continental shelf in Vincennes Bay (104-111°E), using CTD data from instrumented elephant seals spanning from February to November of 2012. We find that Vincennes Bay has East Antarctica’s warmest recorded intrusions of modified Circumpolar Deep Water (mCDW) and that warm mCDW drives basal melt under Vanderford and Underwood ice shelves. Our study also provides the first direct observational evidence for the inflow of meltwater to this region, which increases stratification and hinders DSW formation, and thus AABW production. The Vincennes Bay glaciers, together with the Totten Glacier, drain part of the Aurora Basin, which holds up to 7 m of sea level rise equivalent. Our results highlight the vulnerability of the East Antarctic Ice Sheet to intrusions of mCDW. |
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109 |
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2169-9291 |
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yes |
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8211 |
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Author |
N. Aubone, M. Saraceno, M. L. Torres Alberto, J. Campagna, L. Le Ster, B. Picard, M. Hindell, C. Campagna, C. R. Guinet |
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Title |
Physical changes recorded by a deep diving seal on the Patagonian slope drive large ecological changes |
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Journal |
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Year |
2021 |
Publication |
Journal of Marine Systems |
Abbreviated Journal |
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Volume |
223 |
Issue |
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Pages |
103612 |
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Keywords |
Elephant seals Malvinas current Patagonian shelf slope Southwestern Atlantic Ocean |
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Abstract |
The Patagonian slope is the region where Subantarctic waters and bathymetry give raise to physical and ecological processes that support a rich biodiversity and a large-scale industrial fisheries. Unique among the species that depend on this region is the deep diving southern elephant seal, Mirounga leonina. We report here on changes in the foraging behavior of a female seal explained by the combined effect of a cold and high salinity water mass and a decrease in surface chlorophyll-a concentration. Behavioral and oceanographic data from about 5000 profiles of temperature, conductivity, pressure, light and prey encounters were collected within an area ranging 59.5–61°W and 46–47.5°S, at depths of 300–700 m, on the Patagonian slope, during November–December 2018. A decrease in temperature (0.15 °C) and an increase in salinity (0.03) was found below the mixed layer, during December. Light data revealed a significant increase of irradiance in December (almost reaching the ocean bottom) associated with a decrease of chlorophyll-a in the upper levels. Concomitantly, the seal had a different diving behavior in December, foraging near the surface at night and close to the bottom during daylight hours. Also, the seal doubled the prey capture attempts in December compared to November. This study reveals the importance of ocean physical properties on seal's diving and foraging behavior, and how this changes, although small, can impact on seals diet and body composition during their post-breeding trips. |
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1201 |
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0924-7963 |
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yes |
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Serial |
8771 |
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Author |
Morten Frederiksen, Olivier Gilg, Glenn Yannic |
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Title |
Cross-icecap spring migration confirmed in a high-Arctic seabird, the Ivory Gull Pagophila eburnea |
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Journal |
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Year |
2021 |
Publication |
Ibis |
Abbreviated Journal |
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Volume |
163 |
Issue |
2 |
Pages |
706-714 |
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Keywords |
ecological barrier Greenland icecap high-altitude migration |
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Abstract |
Seabirds rarely cross major terrestrial barriers during seasonal migration, possibly because they have a limited ability to build up fat stores. For the first time, we tracked two Ivory Gulls with GPS loggers during spring migration from the wintering area in Davis Strait to the breeding colony in north-east Greenland. While one bird migrated in March around the southern tip of Greenland, the other delayed migration until May and crossed the Greenland icecap north of 70°N, covering 1345 km in 29 h. Several aspects of the crossing were noteworthy: the track was remarkably direct, the bird made several stops (totalling 6 h) on the icecap, and the bird increased its flying altitude to nearly 3000 m over West Greenland and > 4000 m over East Greenland. |
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1210 |
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0019-1019 |
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yes |
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6348 |
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Author |
Morgan Godard |
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Title |
Caractérisation du comportement alimentaire de l'éléphant de mer Mirounga leonina et liens avec les structures physiques sub-mésoéchelles (1-10km) dans l'océan Austral : une approche par analyse de données fonctionnelles |
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Year |
2021 |
Publication |
Thèse de doctorat en Océanographie |
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De nombreuses questions restent en suspens quant aux relations existantes entre les processus biologiques et physiques dans l'océan Austral. Pour répondre à ces questions, des enregistreurs électroniques sont déployés sur des prédateurs marins, et notamment sur des éléphants de mer austraux. Ces enregistreurs échantillonnent une grande variété de données physiques, biologies ou comportementales à haute fréquence générant ainsi une quantité considérable d’information. L’ensemble de ces données sont dites fonctionnelles car elles présentent un caractère commun : elles évoluent selon un continuum, qu’il soit spatial ou temporel. L’objectif de cette thèse est donc double, il s’agit d’étudier l’activité alimentaire de femelles éléphant de mer en relation avec les processus physiques de l’océan austral, tout en intégrant le caractère fonctionnel des données échantillonnées. Les résultats obtenus montrent que (1) par rapport aux méthodes classiquement employées, les méthodes d’analyse de données fonctionnelles permettent d’identifier une plus grande variété de comportements de plongées au sens biologique défini. (2) Ces approches fonctionnelles sont plus adaptées pour des données aux fréquences d’échantillonnage variable. (3) L’analyse de données fonctionnelles nous permet également d’accéder à la densité de nos individus, reflet de leur condition corporelle, et les comportements de plongées qu’ils adoptent ont une influence réelle sur cette condition corporelle, à différentes échelles de temps. (4) Il existe une relation entre les caractéristiques des masses d’eau rencontrées par les femelles éléphants de mer et les plongées qu’elles effectuent. |
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1201 |
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yes |
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7727 |
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Author |
Minna Palmroth, Maxime Grandin, Theodoros Sarris, Eelco Doornbos, Stelios Tourgaidis, Anita Aikio, Stephan Buchert, Mark A. Clilverd, Iannis Dandouras, Roderick Heelis, Alex Hoffmann, Nickolay Ivchenko, Guram Kervalishvili, David J. Knudsen, Anna Kotova, Han-Li Liu, David M. Malaspina, Günther March, Aurélie Marchaudon, Octav Marghitu, Tomoko Matsuo, Wojciech J. Miloch, Therese Moretto-Jørgensen, Dimitris Mpaloukidis, Nils Olsen, Konstantinos Papadakis, Robert Pfaff, Panagiotis Pirnaris, Christian Siemes, Claudia Stolle, Jonas Suni, Jose van den IJssel, Pekka T. Verronen, Pieter Visser, Masatoshi Yamauchi |
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Title |
Lower-thermosphere–ionosphere (LTI) quantities: current status of measuring techniques and models |
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Journal |
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Year |
2021 |
Publication |
Annales Geophysicae |
Abbreviated Journal |
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Volume |
39 |
Issue |
1 |
Pages |
189-237 |
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Abstract |
The lower-thermosphere–ionosphere (LTI) system consists of the upper atmosphere and the lower part of the ionosphere and as such comprises a complex system coupled to both the atmosphere below and space above. The atmospheric part of the LTI is dominated by laws of continuum fluid dynamics and chemistry, while the ionosphere is a plasma system controlled by electromagnetic forces driven by the magnetosphere, the solar wind, as well as the wind dynamo. The LTI is hence a domain controlled by many different physical processes. However, systematic in situ measurements within this region are severely lacking, although the LTI is located only 80 to 200 km above the surface of our planet. This paper reviews the current state of the art in measuring the LTI, either in situ or by several different remote-sensing methods. We begin by outlining the open questions within the LTI requiring high-quality in situ measurements, before reviewing directly observable parameters and their most important derivatives. The motivation for this review has arisen from the recent retention of the Daedalus mission as one among three competing mission candidates within the European Space Agency (ESA) Earth Explorer 10 Programme. However, this paper intends to cover the LTI parameters such that it can be used as a background scientific reference for any mission targeting in situ observations of the LTI. |
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312 |
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0992-7689 |
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yes |
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7951 |
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Mike Lockwood, Carl Haines, Luke A. Barnard, Mathew J. Owens, Chris J. Scott, Aude Chambodut, Kathryn A. McWilliams |
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Title |
Semi-annual, annual and Universal Time variations in the magnetosphere and in geomagnetic activity: 4. Polar Cap motions and origins of the Universal Time effect |
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Journal |
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Year |
2021 |
Publication |
Journal of Space Weather and Space Climate |
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Volume |
11 |
Issue |
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Pages |
15 |
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Abstract |
We use the am, an, as and the aσ geomagnetic indices to the explore a previously overlooked factor in magnetospheric electrodynamics, namely the inductive effect of diurnal motions of the Earth’s magnetic poles toward and away from the Sun caused by Earth’s rotation. Because the offset of the (eccentric dipole) geomagnetic pole from the rotational axis is roughly twice as large in the southern hemisphere compared to the northern, the effects there are predicted to be roughly twice the amplitude of those in the northern hemisphere. Hemispheric differences have previously been discussed in terms of polar ionospheric conductivities generated by solar photoionization, effects which we allow for by looking at the dipole tilt effect on the time-of-year variations of the indices. The electric field induced in a geocentric frame is shown to also be a significant factor and gives a modulation of the voltage applied by the solar wind flow in the southern hemisphere that is typically a ±30% diurnal modulation for disturbed intervals rising to ±76% in quiet times. For the northern hemisphere these are 15% and 38% modulations. Motion away from/towards the Sun reduces/enhances the directly-driven ionospheric voltages and reduces/enhances the magnetic energy stored in the tail and we estimate that approximately 10% of the effect appears in directly driven ionospheric voltages and 90% in changes of the rate of energy storage or release in the near-Earth tail. The hemispheric asymmetry in the geomagnetic pole offsets from the rotational axis is shown to be the dominant factor in driving Universal Time (UT) variations and hemispheric differences in geomagnetic activity. Combined with the effect of solar wind dynamic pressure and dipole tilt on the pressure balance in the near-Earth tail, the effect provides an excellent explanation of how the observed Russell-McPherron pattern with time-of-year F and UT in the driving power input into the magnetosphere is converted into the equinoctial F-UT pattern in average geomagnetic activity (after correction is made for dipole tilt effects on ionospheric conductivity), added to a pronounced UT variation with minimum at 02–10 UT. In addition, we show that the predicted and observed UT variations in average geomagnetic activity has implications for the occurrence of the largest events that also show the nett UT variation. |
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2115-7251 |
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yes |
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8076 |
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