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Faits marquants 2017

Juillet 2017

27 juillet 2017
A 22.4 m-long shallow firn core was extracted during the 2006/2007 field season from coastal Adélie Land. Annual layer counting based on sub-annual analyses of δ18O and major chemical components was combined with 5 reference years associated with nuclear tests and non-retreat of summer ... Lire la suite »
 

Juin 2017

22 juin 2017
  En datant par le 14C, les granules de vers de terre retrouvées dans une séquence de loess, une équipe pluridisciplinaire de chercheurs a permis de donner, pour la première fois, un cadre chronologique à toutes les phases de redoux de la dernière ... Lire la suite »
 

Mai 2017

18 mai 2017
  Objectives: Stable isotope data provide insight into the reconstruction of ancient human diet. However, cooking may alter the original stable isotope compositions of food due to losses and modifications of biochemical and water components. Methods: To address this issue, carbon, ... Lire la suite »
18 mai 2017
  The eruption of Samalas in Indonesia in 1257 ranks among the largest sulfur-rich eruptions of the Common Era with sulfur deposition in ice cores reaching twice the volume of the Tambora eruption in 1815. Sedimentological analyses of deposits confirm the exceptional size of the event, ... Lire la suite »
16 mai 2017
Abstract: The Arctic is among the fastest warming regions on Earth, but it is also one with limited spatial coverage of multi-decadal instrumental surface air temperature measurements. Consequently, atmospheric reanalyses are relatively unconstrained in this region, resulting in a large spread of ... Lire la suite »
16 mai 2017
  Abstract: Using  new  high-resolution 10Be  measurements in  the  NGRIP,  EDML  and  Vostok  ice  cores,  together  with previously  published  data  from  EDC,  we  present  an  improved ... Lire la suite »
15 mai 2017
Abstract: Polar ice cores are unique climate archives. Indeed, most of them have a continuous stratigraphy and present high temporal resolution of many climate variables in a single archive. While water isotopic records (dD or d18O) in ice cores are often taken as reference for past atmospheric ... Lire la suite »
15 mai 2017
La mesure des isotopes de l’eau dans des carottes de neige courtes est un outil primordial pour étudier la variabilité climatique récente en Antarctique. Encore faut-il pouvoir interpréter de façon quantitative ce signal en termes de variations de ... Lire la suite »

Mars 2017

28 mars 2017
Immigration and mobility in the mediaeval and post-mediaeval periods in Norway has, up until now, mainly been discussed on the basis of historical sources. This paper presents the results of stable oxygen isotope (d18O) analyses of the 1st and 3rd molars from 95 individuals from mediaeval and ... Lire la suite »
28 mars 2017
The production of hydrogen by serpentinization in ultramafic-hosted hydrothermal systems is simulated by coupling thermodynamic and dynamic modeling in the framework of a thermo-hydraulic single-pass model where a high-temperature hydrothermal fluid moves preferentially through a main canal of high ... Lire la suite »
28 mars 2017
Used alone, the isotopic compositions of O and H in ice give insights into the variations of the local temperature, whereas taken together they can provide information on the climatic conditions at the point of origin of the moisture. Recent analyses of snow from shallow pits indicate that the ... Lire la suite »
28 mars 2017
 Human occupation in Europe strongly fluctuated over the Quaternary. Archaeological records suggest an intermittent human occupation in Western Europe between 900 and 500 ka, especially in the north of Europe at latitude higher than 45°N. On the opposite, southern Europe, more stable from ... Lire la suite »
27 mars 2017
  Oxygen and carbon isotope compositions of fossil bird eggshell calcite (δ18Ocalc and δ13Ccalc) are regularly used to reconstruct paleoenvironmental conditions. The δ18Ocalc values mainly reflect the oxygen isotope composition of the waters ingested by birds (δ18Ow), ... Lire la suite »
27 mars 2017
This study is the first presenting annually resolved chronologies of both δ18O and δ13C in Nothofagus pumilio and Fitzroya cupressoides trees from Northern Patagonia. Interannual variability in δ18O and δ13C was assessed over the period 1952-2011. Based on these ... Lire la suite »
24 mars 2017
  Au cours des 40 dernières années, la recherche sur les carottes de glace a produit des résultats de référence pour l’évolution de la température polaire et de la composition atmosphérique au cours des 800 000 dernières ... Lire la suite »
24 mars 2017
  As part of its ongoing project on repositories for high-activity, long-lived radioactive waste, a 2000 m deep borehole was drilled by the French Nuclear Waste Agency (ANDRA) in the layered structure of alternating aquifers and aquitards of the Eastern Paris Basin. Among the information ... Lire la suite »
24 mars 2017
This article presents a reconstruction of summer droughts in France based on annually resolved, absolutely dated chronologies of oxygen isotope ratios (δ18O) in tree ring cellulose from Quercus spp. Samples were taken from living trees and timber wood from historic buildings at two sites: ... Lire la suite »
24 mars 2017
In palaeoclimate reconstructions, the combination of proxy records measured in different climate archives is challenging because of the uncertainties associated with each proxy, but it can also help reduce some of these uncertainties. Here, we present a novel approach to combine speleothem and ... Lire la suite »
23 mars 2017
  Very little is known about Neanderthal cultures, particularly early ones. Other than lithic implements and exceptional bone tools, very few artefacts have been preserved. While those that do remain include red and black pigments and burial sites, these indications of modernity are ... Lire la suite »
23 mars 2017
  In this article, we present a first synthesis of the chronology of Cussac Cave (Dordogne, SW France). This deep cavern (1.6 km), discovered in 2000, is very well preserved (e.g. intact floors) and thus favorable to research, especially given its rare association of parietal art and ... Lire la suite »
16 mars 2017
Past climate is an important benchmark to assess the ability of climate models to simulate key processes and feedback. Model–data comparisons can help to constrain the uncertainties associated with transfer functions. We have put together a global database of proxy records of oxygen (d18O), ... Lire la suite »
15 mars 2017
Pour l’instant, l’application de la théorie des valeurs extrêmes était limitée aux systèmes qui décrivent la dynamique d’un point dans le temps. Ce cadre est utile pour étudier des phénomènes physiques localisés ... Lire la suite »
14 mars 2017
Interglacials, including the present (Holocene) period, are warm, low land ice extent (high sea level), end-members of glacial cycles. Based on a sea level definition, we identify eleven interglacials in the last 800,000 years. Data compilations suggest that despite spatial heterogeneity, Marine ... Lire la suite »
07 mars 2017
During the austral summer 2016-17, an infrared spectrometer monitoring water stable isotopes in the vapour has been deployed by Camille Bréant from LSCE (Laboratoire des Sciences du Climat et de l’Environnement, Paris, France) at the coastal station of Dumont d’Urville in East ... Lire la suite »

Février 2017

02 février 2017
Storms and tsunamis, which may seriously endanger  human  society,  are  amongst  the  most  devastating  marine catastrophes that can occur in coastal areas. Many such events are known  and have been reported  for the Mediterranean, a region where ... Lire la suite »
02 février 2017
  Human occupation in Europe strongly fluctuated over the Quaternary. Archaeological records suggest an intermittent human occupation in Western Europe between 900 and 500 ka, especially in the north of Europe at latitude higher than 45°N. On the opposite, southern Europe, more stable ... Lire la suite »
02 février 2017
  Very little is known about Neanderthal cultures1, particularly early ones. Other than lithic implements and exceptional bone tools2, very few artefacts have been preserved. While those that do remain include red and black pigments3 and curil wites4, these indications of modernity are ... Lire la suite »
 

Janvier 2017

26 janvier 2017
PURPOSE Vertical transfer of solid matter in soils (bioturbation and translocation) is responsible for changes in soil properties over time through the redistribution of most of the soil constituents with depth. Such transfers are, however, still poorly quantified. MATERIALS AND METHODS In this ... Lire la suite »
26 janvier 2017
  RATIONALE: Compound-specific stable carbon isotope analysis by GC/C/IRMS is widely used in studies of environmental or biological functioning. In the case of derivatized molecules, a calibration might be required due to added non-analyte carbon and in some cases non-stoichiometric ... Lire la suite »
26 janvier 2017
The Nussloch loess–palaeosol sequence (Rhine Valley, Germany) is considered to be one of the most complete records of the last glacial period in Western Europe due to its very high sedimentation rate and its good chronological control. This sequence is therefore a good framework in which to ... Lire la suite »
26 janvier 2017
Loess–paleosol sequences in the Vojvodina region in the southeastern Carpathian Basin have been intensively studied to obtain a high-resolution stratigraphical framework for the Upper Pleistocene in this part of Europe. In these studies, millennial-scale sedimentation variations in the Upper ... Lire la suite »
26 janvier 2017
  As part of its ongoin pro*ecv on repositories for high-activity, long-lived radioactive waste, a 2000 m deep borehole was drilled by the French Nuclear Waste Agency (ANDRA) in the layered structure of alternating aquifers and aquitards of the Eastern Paris Basin. Among the information ... Lire la suite »
26 janvier 2017
  Abstract The soil memory recorded in paleosols of loess-paleosol sequences is an important contributor to our understanding of past climatic conditions. Molecular proxies based on the organic matter preserved in paleosols form an essential part of this record, but the long-term ... Lire la suite »
16 janvier 2017
  Water stable isotopes in central Antarctic ice cores are critical to quantify past temperature changes. Accurate temperature reconstructions require to understand the processes controlling surface snow isotopic composition. Isotopic fractionation processes occurring in the atmosphere and ... Lire la suite »
13 janvier 2017
  Abstract: Au cours des 40 dernières années, la recherche sur les carottes de glace a produit des résultats de référence pour l’évolution de la température polaire et de la composition atmosphérique au cours des 800 000 ... Lire la suite »
12 janvier 2017
Abstract: Orbital tuning is central for ice core chronologies beyond annual layer counting, available back to 60 ka (i.e. thousands of years before 1950) for Greenland ice cores. While several complementary orbital tuning tools have recently been developed using δ18Oatm, δO2⁄N2 ... Lire la suite »
12 janvier 2017
  Abstract: The isotopic compositions of oxygen and hydrogen in ice cores are invaluable tools for the reconstruction of past climate variations. Used alone, they give insights into the variations of the local temperature, whereas taken together they can provide information on the climatic ... Lire la suite »
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