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Title Archival of the water stable isotope signal in East Antarctic ice cores Type Journal
Year 2016 Publication The cryosphere discuss. Abbreviated Journal (up)
Volume 2016 Issue Pages 1-33
Keywords
Abstract The oldest ice core records are obtained from the East Antarctic plateau. Water stable isotopes records are key for reconstructions of past climatic conditions both over the ice sheet and at the evaporation source. The accuracy of such climate reconstructions crucially depends on the knowledge of all the processes affecting the water vapour, precipitation and snow isotopic composition. Atmospheric fractionation processes are well understood and can be integrated in Rayleigh distillation and complex isotope enabled climate models. However, a comprehensive quantitative understanding of processes potentially altering the snow isotopic composition after the deposition is still missing, especially for exchanges between vapour and snow. In low accumulation sites such as found on the East Antarctic Plateau, these poorly constrained processes are especially likely to play a significant role. This limits the interpretation of isotopic composition from ice core records, specifically at short time scales. Here, we combine observations of isotopic composition in the vapour, the precipitation, the surface snow and the buried snow from various sites of the East Antarctic Plateau. At the seasonal scale, we highlight a significant impact of metamorphism on surface snow isotopic signal compared to the initial precipitation isotopic signal. In particular, in summer, exchanges of water molecules between vapour and snow are driven by the sublimation/condensation cycles at the diurnal scale. Using highly resolved isotopic composition profiles from pits in five East Antarctic sites, we identify a common 20?cm cycle which cannot be attributed to the seasonal variability of precipitation. Altogether, the smaller range of isotopic compositions observed in the buried and in the surface snow compared to the precipitation, and also the reduced slope between surface snow isotopic composition and temperature compared to precipitation, constitute evidences of post-deposition processes affecting the variability of the isotopic composition in the snow pack. To reproduce these processes in snow-models is crucial to understand the link between snow isotopic composition and climatic conditions and to improve the interpretation of isotopic composition as a paleoclimate proxy.
Programme 1013
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Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1994-0440 ISBN 1994-0440 Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6569
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Author
Title Type Journal
Year 2017 Publication Atmos. chem. phys. Abbreviated Journal (up)
Volume 17 Issue 1 Pages 691-704
Keywords
Abstract
Programme 1013
Campaign
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1680-7324 ISBN 1680-7324 Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6573
Permanent link to this record
 
 
Author
Title Stable boundary?layer regimes at Dome C, Antarctica: observation and analysis Type Journal
Year 2017 Publication Quarterly journal of the royal meteorological society Abbreviated Journal (up)
Volume 143 Issue 704 Pages 1241-1253
Keywords Antarctic atmosphere critical transition stable boundary layer wind?speed threshold
Abstract Investigation of meteorological measurements along a 45 m tower at Dome C on the high East Antarctic Plateau revealed two distinct stable boundary layer (SBL) regimes at this location. The first regime is characterized by strong winds and continuous turbulence. It results in full vertical coupling of temperature, wind magnitude and wind direction in the SBL. The second regime is characterized by weak winds, associated with weak turbulent activity and very strong temperature inversions reaching up to 25 K in the lowest 10 m. Vertical temperature profiles are generally exponentially shaped (convex) in the first regime and ?convex?concave?convex? in the second. The transition between the two regimes is particularly abrupt when looking at the near?surface temperature inversion and it can be identified by a 10 m wind?speed threshold. With winds under this threshold, the turbulent heat supply toward the surface becomes significantly lower than the net surface radiative cooling. The threshold value (including its range of uncertainty) appears to agree with recent theoretical predictions from the so?called ?minimum wind speed for sustainable turbulence? (MWST) theory. For the quasi?steady, clear?sky winter cases, the relation between the near?surface inversion amplitude and the wind speed takes a characteristic ?S? shape. Closer analysis suggests that this relation corresponds to a ?critical transition? between a steady turbulent and a steady ?radiative? regime, with a dynamically unstable branch in the transition zone. These fascinating characteristics of the Antarctic boundary layer challenge present and future numerical models to represent this region in a physically correct manner.
Programme 1013
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0035-9009 ISBN 0035-9009 Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6574
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Author
Title Extensive lake sediment coring survey on Sub-Antarctic Indian Ocean Kerguelen Archipelago (French Austral and Antarctic Lands) Type Communication
Year 2016 Publication European geophysical union (egu), viennes, austria Abbreviated Journal (up)
Volume Issue Pages
Keywords
Abstract
Programme 1094
Campaign
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6575
Permanent link to this record
 
 
Author
Title Type Communication
Year 2016 Publication European geophysical union (egu), viennes, austria. Abbreviated Journal (up)
Volume Issue Pages
Keywords
Abstract The Polar-regions are changing rapidly as greenhouse warming is continuing with huge impact on e.g. sea ice extent and snow cover. This change triggers teleconnections to low latitude areas challenging societies and human activity. We have, however, very little quantitative information of past climate in the Polar-regions that can be used to evaluate the potential responses and the response patterns to forcing changes and changes in boundary
conditions. Whatever anthropogenic changes may occur in the future, they will be superimposed on, and interact with, natural climate variations due to all the forcing we are aware of. This means we need to better document past climate/environmental variability of the Polar-regions. Especially in the Southern Ocean there are few time series recording past climate due to few suitable land areas and the few Sub-Antarctic Islands is remote and has cumbersome logistics. Continuous terrestrial records from this region are therefore urgently needed for constraining future scenarios from earth system models. Glaciers and ice caps are still ubiquitous in the Polar-regions, although they are rapidly shrinking due to the on-going warming. The continuous sedimentary records produced by glaciers, which are stored in downstream lakes, represent supreme archives of past variability wherefrom quantitative information of key climate system components can be extracted. Kerguelen Island is located within the Antarctic Circumpolar Current and the Southern Westerly wind belt and contains several glaciers and smaller ice caps. Terrestrial archives recording past history of the glaciers at Kerguelen thus have a unique potential to record past changes in oceanic and atmospheric circulation patterns from southern mid-latitudes. Here we present preliminary
results from the first distal glacier-fed lake that is sampled from Kerguelen Island. A 2.8 m long sediment core was obtained from Lac Guynemer (121masl.) located at the Peninsule Loranchet at the northern part of Kerguelen Island. The lake receives glacial meltwater from Glacier Guynemer, a small cirque glacier at the Pic Guynemer (1188masl.). The sediment core was analyzed with high-resolution core scanning X-ray fluorescence (XRF), magnetic
parameters, loss-on-ignition and dry bulk density, to reconstruct past glacier variability of Glacier Guynemer. The sediment record covers the last 5000 years and show a dynamic glacier responding to the changing boundary conditions during the Neoglacial.
Programme 1094
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6576
Permanent link to this record
 
 
Author F Bonadonna
Title The Lords of the perfumes. (plenary talk) Type Communication
Year 2016 Publication Abbreviated Journal (up)
Volume Issue Pages
Keywords
Abstract
Programme 354
Campaign
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6579
Permanent link to this record
 
 
Author M Berges
Title Impact of long-term manipulation on a blue petrel (Halobaena caerulea) colony from Kerguelen Islands Type Master 2
Year 2017 Publication Abbreviated Journal (up)
Volume Issue Pages
Keywords
Abstract
Programme 354
Campaign
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6581
Permanent link to this record
 
 
Author Camille reverchon
Title Type Master 1
Year 2017 Publication Abbreviated Journal (up)
Volume Issue Pages
Keywords
Abstract
Programme 1013
Campaign
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6583
Permanent link to this record
 
 
Author
Title Intra- and inter-individual variation in the foraging ecology of a generalist subantarctic seabird, the gentoo penguin Type Journal
Year 2017 Publication Marine ecology progress series Abbreviated Journal (up)
Volume 578 Issue Pages 227-242
Keywords Behavioural consistency Diving behaviour Feeding ecology Foraging behaviour Individual specialisations Pygoscelis papua Stable isotopes
Abstract
Programme 394
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0171-8630, 1616-1599 ISBN 0171-8630, 1616-1599 Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6584
Permanent link to this record
 
 
Author
Title Combined bio-logging and stable isotopes reveal individual specialisations in a benthic coastal seabird, the Kerguelen shag Type Journal
Year 2017 Publication Plos one Abbreviated Journal (up)
Volume 12 Issue 3 Pages e0172278
Keywords Birds Animal sexual behavior Blood Diet Ecological niches Feathers Foraging Predation
Abstract Individual specialisations, which involve the repetition of specific behaviours or dietary choices over time, have been suggested to benefit animals by avoiding competition with conspecifics and increasing individual foraging efficiency. Among seabirds, resident and benthic species are thought to be good models to study inter-individual variation as they repetitively exploit the same environment. We investigated foraging behaviour, isotopic niche and diet in the Kerguelen shag Phalacrocorax verrucosus during both the incubation and chick-rearing periods for the same individuals to determine the effect of sex, breeding stage, body mass and morphometrics on mean foraging metrics and their consistency. There were large differences between individuals in foraging behaviour and consistency, with strong individual specialisations in dive depths and heading from the colony. Stable isotopes revealed specialisations in feeding strategies, across multiple temporal scales. Specifically, individuals showed medium term specialisations in feeding strategies during the breeding season, as well as long-term consistency. A clustering analysis revealed 4 different foraging strategies displaying significantly different ?15N values and body masses. There were no sex or stage biases to clusters and individuals in different clusters did not differ in their morphology. Importantly, the results suggest that the different strategies emphasized were related to individual prey preferences rather than intrinsic characteristics.
Programme 394
Campaign
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN 1932-6203 Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6585
Permanent link to this record