7 Feb 2024
Job Information
- Organisation/Company
CNRS- Department
Centre de Recherche et d'Enseignement des Géosciences de l'Environnement- Research Field
Environmental science
Environmental science » Earth science
Environmental science » Global change- Researcher Profile
Recognised Researcher (R2)- Country
France- Application Deadline
27 Feb 2024 - 23:59 (UTC)- Type of Contract
Temporary- Job Status
Full-time- Hours Per Week
35- Offer Starting Date
1 Apr 2024- Is the job funded through the EU Research Framework Programme?
H2020- Is the Job related to staff position within a Research Infrastructure?
No
Offer Description
The cosmogenic nuclides of beryllium-10 (10Be) and chlorine-36 (36Cl), which are produced by the interaction of cosmic rays on target atoms present in the Earth's atmosphere, can be extracted from polar ice. They are used to document variations in past solar activity and in the Earth's magnetic field. The 36Cl/10Be isotopic ratio can also be used for ice cores dating using the principle of radioactive decay. The use of this isotopic ratio is based on the strong assumption that, once produced, 10Be and 36Cl behave in the same way (atmospheric residence time, transport modes, deposition and record in snow, etc.), however, the values obtained at different sites in Greenland and Antarctica differ from the theoretical production ratio.
Low accumulation sites, where the oldest ice can be found, are those where the preservation of chlorine and 36Cl is the most complex. During interglacial periods, some of the chlorine and 36Cl deposited on the snow pack is mobile and re-emitted into the atmosphere (Delmas et al., 2004, Pivot et al., 2019). The 10Be signal can also be disturbed in deep ice (Raisbeck et al., 2006).
New 36Cl and 10Be data from sites with contrasting accumulations, during different climatic periods, are therefore needed to better understand their deposition and their record in glaciological archives and thus improve dating based on the 36Cl/10Be isotope ratio. The chemical composition of the ice will be an essential parameter that must also be taken into account.
This work is part of the European H2020 project Beyond EPICA-Oldest Ice (https://www.beyondepica.eu/en/ ). The aim is to study the climatic response to orbital forcing during the Mid-Pleistocene Transition, around 1 million years ago, when glacial/interglacial cyclicity evolved from 40,000 years to 100,000 years. A deep ice core is currently being drilled in the vicinity of the Dome C - Concordia station in Antarctica, its dating is one of the tasks of the project Beyond-EPICA.
The candidate's task will be to extract, by chemical treatments, the 10Be and the 36Cl from ice samples from different sites in Antarctica, with varying accumulations, for different climatic periods (glacial and interglacial and the current period). Automation of a part of the sample preparation is planned. A specific attention will have to be taken when handling the samples to avoid any contamination.
The samples will be cut in a negative-temperature cold room.
This work will be carried out in collaboration with the French and European partners of the Beyond EPICA-Oldest Ice project.
CEREGE is located on the Petit Arbois plateau, Technopole Environnement Arbois - Méditerranée, Avenue Louis Philibert, Les Milles-Aix en Provence.
The person recruited will join CEREGE's Climate team and will work closely with Mélanie Baroni and Edouard Bard.
Requirements
- Research Field
- Environmental science
- Education Level
- PhD or equivalent
- Research Field
- Environmental science
- Education Level
- PhD or equivalent
- Research Field
- Environmental science
- Education Level
- PhD or equivalent
- Languages
- FRENCH
- Level
- Basic
- Research Field
- Environmental science
- Years of Research Experience
- 1 - 4
- Research Field
- Environmental science » Earth science
- Years of Research Experience
- 1 - 4
- Research Field
- Environmental science » Global change
- Years of Research Experience
- 1 - 4
Additional Information
Eligibility criteria
The candidate should have a sound knowledge of analytical chemistry, chemistry of the the ice and the atmosphere, climatology and palaeoclimatology. He/she should be familiar in handling ice samples to measure trace elements. Knowledge of the theory of cosmogenic nuclide production in the atmosphere would be appreciated as would knowledge in dating techniques. He/she should be familiar with and apply the health and safety conditions in a chemistry laboratory, be autonomous and be fluent in English. A driving licence is recommended.
Candidates should submit a letter of motivation (maximum 2 pages), and a detailed CV with a list of publications and provide two letters of recommendation.
Additional comments
Beyond EPICA - Oldest Ice Project
- Website for additional job details
https://emploi.cnrs.fr/Offres/CDD/UMR7330-MELBAR-002/Default.aspx
Work Location(s)
- Number of offers available
- 1
- Company/Institute
- Centre de Recherche et d'Enseignement des Géosciences de l'Environnement
- Country
- France
- City
- AIX EN PROVENCE
- Geofield
Where to apply
- Website
https://emploi.cnrs.fr/Candidat/Offre/UMR7330-MELBAR-002/Candidater.aspx
Contact
- City
AIX EN PROVENCE- Website
http://www.cerege.fr
STATUS: EXPIRED