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Guillaume Hubert, Sébastien Aubry. (2018). Analysis of Exposure to Solar and Galactic Cosmic Radiations of Flights Representative of the European International Air Traffic (Vol. 190).
Abstract: This study analyzed the impact of galactic and solar cosmic rays on ambient dose equivalent during airline travel. A high statistic of flights are considered, which is representative of European international air traffic. Flight paths are based on the Eurocontrol Demand Data Repository and consider realistic flight plans with and without regulations or updated with radar data from the Central Flow Management Unit. Ambient dose equivalent during flights was investigated during quiet solar periods and extreme solar flare events. Thus, the statistical analyses presented here take into account route characteristics (departure, arrival, continent, etc.) and space weather conditions. The findings of this work show the important influence of flight path, particularly the latitude, which drives the cutoff rigidity variations. Moreover, dose values vary drastically during ground level enhancement events, with the route path (latitude, longitude and altitude) and the phasing of the solar event. This study highlights the importance of monitoring these solar events and developing a physical approach to obtain reliable assessment of ambient dose equivalents.
Programme: 1112
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Aurélie Goutte, Yves Cherel, Carine Churlaud, Jean-Pierre Ponthus, Guillaume Massé, Paco Bustamante. (2015). Trace elements in Antarctic fish species and the influence of foraging habitats and dietary habits on mercury levels (Vol. 538).
Abstract: This study aims at describing and interpreting concentration profiles of trace elements in seven Antarctic fish species (N=132 specimens) off Adélie Land. Ichthyofauna plays a key role in the Antarctic ecosystem, as they occupy various ecological niches, including cryopelagic (ice-associated), pelagic, and benthic habitats. Firstly, trace element levels in the studied specimens were similar to those previously observed in fish from the Southern Ocean. Apart from manganese and zinc, concentrations of arsenic, cadmium, copper, iron, mercury (Hg), nickel, selenium and silver differed among fish species. Muscle δ13C and δ15N values were determined to investigate whether the fish foraging habitats and dietary habits could explain Hg levels. Species and foraging habitat (δ13C) were strong predictors for variations of Hg concentrations in muscle tissues. The highest Hg contamination was found in shallow benthic fish compared to cryopelagic and pelagic fish. This pattern was likely due to the methylation of Hg in the coastal sediment and the photodemethylation by ultraviolet radiation in surface waters.
Keywords: Heavy metals Nototheniidae Southern Ocean Stable isotopes
Programme: 1010
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Makoto Sampei, Louis Fortier, Patrick Raimbault, Kohei Matsuno, Yoshiyuki Abe, Bernard Quéguiner, Augustin Lafond, Marcel Babin, Toru Hirawake. (2021). An estimation of the quantitative impacts of copepod grazing on an under sea-ice spring phytoplankton bloom in western Baffin Bay, Canadian Arctic (Vol. 9).
Abstract: This study aimed to quantify the impact of copepod grazing on the productivity of phytoplankton during an under sea-ice spring phytoplankton bloom (USPB) in western Baffin Bay. To quantify positive and/or negative impacts of copepod grazing on primary production and the interaction between copepod grazing and phytoplankton species, we sampled seawater and zooplankton under the landfast sea ice every 2–3 days between May 24 and July 10, 2016. Samples were analyzed for estimation of primary production, chlorophyll-a (chl-a) concentration, diatom abundance, and copepod fecal pellet (FP) production/grazing rate. Analyses of chl-a concentration, primary production, and FP production/grazing rate revealed clear temporal changes and a mismatch between primary production and copepod consumption. The FP production/grazing rate reached a maximum (9.4/31.2 mg C m–2 d–1) on June 16 before the USPB phase and suddenly decreased to 0.7/2.4 mg C m–2 d–1 on June 21, despite an increase in primary production to 74.0 mg C m–2 d–1. The copepod grazing rate (3.7 mg C m–2 d–1) was low relative to primary production (344.6 mg C m–2 d–1) during the USPB phase (after June 20). While our estimates illustrate that copepod grazing did not limit the maximum daily primary production during the USPB, the low grazing pressure (2% of primary production) may have been an additional contributor to the reduction in total primary productivity at the end of the USPB period due primarily to the low supply of regenerated nitrogen-containing nutrients to drive regenerated production.
Programme: 1164
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Anny-Chantal Levasseur-Regourd, Jessica Agarwal, Hervé Cottin, Cécile Engrand, George Flynn, Marco Fulle, Tamas Gombosi, Yves Langevin, Jérémie Lasue, Thurid Mannel, Sihane Merouane, Olivier Poch, Nicolas Thomas, Andrew Westphal. (2018). Cometary Dust (Vol. 214).
Abstract: This review presents our understanding of cometary dust at the end of 2017. For decades, insight about the dust ejected by nuclei of comets had stemmed from remote observations from Earth or Earth’s orbit, and from flybys, including the samples of dust returned to Earth for laboratory studies by the Stardust return capsule. The long-duration Rosetta mission has recently provided a huge and unique amount of data, obtained using numerous instruments, including innovative dust instruments, over a wide range of distances from the Sun and from the nucleus. The diverse approaches available to study dust in comets, together with the related theoretical and experimental studies, provide evidence of the composition and physical properties of dust particles, e.g., the presence of a large fraction of carbon in macromolecules, and of aggregates on a wide range of scales. The results have opened vivid discussions on the variety of dust-release processes and on the diversity of dust properties in comets, as well as on the formation of cometary dust, and on its presence in the near-Earth interplanetary medium. These discussions stress the significance of future explorations as a way to decipher the formation and evolution of our Solar System.
Programme: 1120
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Yves Cherel. (2020). A review of Southern Ocean squids using nets and beaks (Vol. 50).
Abstract: This review presents an innovative approach to investigate the teuthofauna from the Southern Ocean by combining two complementary data sets, the literature on cephalopod taxonomy and biogeography, together with predator dietary investigations. Sixty squids were recorded south of the Subtropical Front, including one circumpolar Antarctic (Psychroteuthis glacialis Thiele, 1920), 13 circumpolar Southern Ocean, 20 circumpolar subantarctic, eight regional subantarctic, and 12 occasional subantarctic species. A critical evaluation removed five species from the list, and one species has an unknown taxonomic status. The 42 Southern Ocean squids belong to three large taxonomic units, bathyteuthoids (n = 1 species), myopsids (n = 1), and oegopsids (n = 40). A high level of endemism (21 species, 50%, all oegopsids) characterizes the Southern Ocean teuthofauna. Seventeen families of oegopsids are represented, with three dominating families, onychoteuthids (seven species, five endemics), ommastrephids (six species, three endemics), and cranchiids (five species, three endemics). Recent improvements in beak identification and taxonomy allowed making new correspondence between beak and species names, such as Galiteuthis suhmi (Hoyle 1886), Liguriella podophtalma Issel, 1908, and the recently described Taonius notalia Evans, in prep. Gonatus phoebetriae beaks were synonymized with those of Gonatopsis octopedatus Sasaki, 1920, thus increasing significantly the number of records and detailing the circumpolar distribution of this rarely caught Southern Ocean squid. The review extends considerably the number of species, including endemics, recorded from the Southern Ocean, but it also highlights that the corresponding species to two well-described beaks (Moroteuthopsis sp. B and Psychroteuthis sp. B) are still unknown.
Programme: 109
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Douglas Thomas A, Loseto Lisa L, Macdonald Robie W, Outridge Peter, Dommergue Aurélien, Poulain Alexandre, Amyot Marc, Barkay Tamar, Berg Torunn, Chételat John, Constant Philippe, Evans Marlene, Ferrari Christophe, Gantner Nikolaus, Johnson Matthew S, Kirk Jane, Kroer Niels, Larose Catherine, Lean David, Nielsen Torkel Gissel, Poissant Laurier, Rognerud Sigurd, Skov Henrik, Sørensen Søren, Wang Feiuye, Wilson Simon, Zdanowicz Christian M, . (2012). The fate of mercury in Arctic terrestrial and aquatic ecosystems, a review
. Environ. Chem., 9 (4), 321–355 .
Abstract: This review is the result of a series of multidisciplinary meetings organised by the Arctic Monitoring and
Assessment Programme as part of their 2011 Assessment ‘Mercury in the Arctic’. This paper presents the state-of-the-art
knowledge on the environmental fate of mercury following its entry into the Arctic by oceanic, atmospheric and terrestrial
pathways. Our focus is on the movement, transformation and bioaccumulation of Hg in aquatic (marine and fresh water)
and terrestrial ecosystems. The processes most relevant to biological Hg uptake and the potential risk associated with Hg
exposure in wildlife are emphasised. We present discussions of the chemical transformations of newly deposited or
transported Hg in marine, fresh water and terrestrial environments and of the movement of Hg from air, soil and water
environmental compartments into food webs. Methylation, a key process controlling the fate of Hg in most ecosystems,
and the role of trophic processes in controlling Hg in higher order animals are also included. Case studies on Eastern
Beaufort Sea beluga (Delphinapterus leucas) and landlocked Arctic char (Salvelinus alpinus) are presented as examples of
the relationship between ecosystem trophic processes and biologic Hg levels. We examine whether atmospheric mercury
depletion events (AMDEs) contribute to increased Hg levels in Arctic biota and provide information on the links between
organic carbon and Hg speciation, dynamics and bioavailability. Long-term sequestration of Hg into non-biological
archives is also addressed. The review concludes by identifying major knowledge gaps in our understanding, including:
(1) the rates of Hg entry into marine and terrestrial ecosystems and the rates of inorganic and MeHg uptake by Arctic
microbial and algal communities; (2) the bioavailable fraction of AMDE-related Hg and its rate of accumulation by biota
and (3) the fresh water and marine MeHg cycle in the Arctic, especially the marine MeHg cycle.
Keywords: bioavailability, biomagnification, demethylation, fresh water ecosystems, methylation, trophic processes.,
Programme: 399
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Stephanie Jenouvrier. (2013). Impacts of climate change on avian populations (Vol. 19).
Abstract: This review focuses on the impacts of climate change on population dynamics. I introduce the MUP (Measuring, Understanding, and Predicting) approach, which provides a general framework where an enhanced understanding of climate-population processes, along with improved long-term data, are merged into coherent projections of future population responses to climate change. This approach can be applied to any species, but this review illustrates its benefit using birds as examples. Birds are one of the best-studied groups and a large number of studies have detected climate impacts on vital rates (i.e., life history traits, such as survival, maturation, or breeding, affecting changes in population size and composition) and population abundance. These studies reveal multifaceted effects of climate with direct, indirect, time-lagged, and nonlinear effects. However, few studies integrate these effects into a climate-dependent population model to understand the respective role of climate variables and their components (mean state, variability, extreme) on population dynamics. To quantify how populations cope with climate change impacts, I introduce a new universal variable: the ‘population robustness to climate change.’ The comparison of such robustness, along with prospective and retrospective analysis may help to identify the major climate threats and characteristics of threatened avian species. Finally, studies projecting avian population responses to future climate change predicted by IPCC-class climate models are rare. Population projections hinge on selecting a multiclimate model ensemble at the appropriate temporal and spatial scales and integrating both radiative forcing and internal variability in climate with fully specified uncertainties in both demographic and climate processes.
Keywords: climatic niche extinction extreme events IPCC stochastic population projection uncertainties
Programme: 109
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Rune Dietz, Christian Sonne, Niladri Basu, Birgit Braune, Todd O'Hara, Robert J. Letcher, Tony Scheuhammer, Magnus Andersen, Claus Andreasen, Dennis Andriashek, Gert Asmund, Aurore Aubail, Hans Baagøe, Erik W. Born, Hing M. Chan, Andrew E. Derocher, Philippe Grandjean, Katrina Knott, Maja Kirkegaard, Anke Krey, Nick Lunn, Francoise Messier, Marty Obbard, Morten T. Olsen, Sonja Ostertag, Elizabeth Peacock, Aristeo Renzoni, Frank F. Rigét, Janneche Utne Skaare, Gary Stern, Ian Stirling, Mitch Taylor, Øystein Wiig, Simon Wilson, Jon Aars. (2013). What are the toxicological effects of mercury in Arctic biota? (Vol. 443).
Abstract: This review critically evaluates the available mercury (Hg) data in Arctic marine biota and the Inuit population against toxicity threshold values. In particular marine top predators exhibit concentrations of mercury in their tissues and organs that are believed to exceed thresholds for biological effects. Species whose concentrations exceed threshold values include the polar bears (Ursus maritimus), beluga whale (Delphinapterus leucas), pilot whale (Globicephala melas), hooded seal (Cystophora cristata), a few seabird species, and landlocked Arctic char (Salvelinus alpinus). Toothed whales appear to be one of the most vulnerable groups, with high concentrations of mercury recorded in brain tissue with associated signs of neurochemical effects. Evidence of increasing concentrations in mercury in some biota in Arctic Canada and Greenland is therefore a concern with respect to ecosystem health.
Keywords: Birds Exposure Fish Heavy metals Mammals Threshold levels
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Gilles Durand, Mauro Dolci, Giuliano Nucciarelli, Lucia Sabbatini. (2006). Progress report : Coordination of IRAIT based activity for campaigns 2009/2012 Teramo 09&10 September 2009.
Abstract: This reports the first coordination meeting of the IRAIT based experiments.
Goal : temptative view of the programs at 3 year distance, in order to coordinate the activities of Agencies and institutes.
Detailed activity and requirements for agencies for the two next summer campaigns.
The defrosting of telescopes were discussed including COCHISE and IRAIT
The Future astrophysic shelter was discussed
The cooling system and power requirements were discussed.
Programme: 1040
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A. Wargnier. (2020). Characterising the time profiles of relativistic solar energetic particle events observed by neutron monitors.
Abstract: This Report Presents The Result Of The Measurement Of Characteristic Times For Relativistic Solar Energetic Par- Ticle Events Observed By Neutron Monitors. The Typical Profile Of A Solar Event Observed By Neutrons Monitors Is A Fast Rise And A Slow Decay. But These Times Differ Between Events (From A Few Minutes To Several Hours) And Quantifying Them Is Interesting. In Fact, Studying These Characteristic Times Allows Us To Better Understand Solar High Energy Events. For This, We Used The Neutron Monitor Database (Nmdb) [1] And Python To Compute The Rise Time And The Decay Time. We Observed That There Is A Linear Relationship Between Rise Time And Decay Time Of These Solar Events.there Are Some Possible Interpretations For These Characteristic Times. These Times May Be Related To The Dura- Tion Of Particle Acceleration Or The Propagation Of The Particles In The Interplanetary Medium. We Looked Then For A Link Between The Measurement Of Neutron Monitors At The Earth And The Solar Activity: In X-rays, And The Microwave Domain. Furthermore, We Studied The Fluctuations Of The Interplanetary Magnetic Field. However, All These Attempts Were Unsuccessful To Find A Relation With The Rise Time Measured By Neutron Monitors. But Ejection Speeds Of Coronal Mass Ejections And Rise Time Solar Events Detected By Neutron Monitors May Be Linked.
Programme: 227
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