Les isotopes stables de l'eau en Atlantique Nord

Abstract : This thesis focuses on two regions of the North Atlantic: the subtropical gyre and the subpolar gyre. This large coverage allows an investigation of the water cycle in different hydrological regimes, where various processes take place such as sea ice seasonal cycle, rivers runoff, continental ice melt and advection of air and water masses. In the subtropical region, the variability of the isotopic composition of the water vapor is studied to understand the role of evaporation and mixing with free troposphere in humidity and isotopic compositions at the ocean surface. In particular, new data collected during summer 2012 (STRASSE cruise) gave the opportunity to explore kinetic fractionation processes during oceanic evaporation and air renewal in the atmospheric boundary layer. In the subpolar region, the surface circulation is cyclonic and transfers cold and fresh water from the arctic region to the interior of the subpolar gyre. For this thesis, data were collected between 2010 and 2014 from oceanographic cruises and commercial vessels to study the gyre interior and the main coastal currents carrying water from the arctic to lower latitudes. The study is mainly focused on the Labrador Current. There, isotopic measurements are used to identify the freshwater sources and to consider the following questions: How is the salinity of fresh currents affected by the sea ice formation and melting? How is the contribution of meteoric waters changing in a context of an acceleration of the melting of continental glaciers?
Document type :
Theses
Complete list of metadatas

Cited literature [161 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01195581
Contributor : Abes Star <>
Submitted on : Tuesday, September 8, 2015 - 10:40:08 AM
Last modification on : Tuesday, June 18, 2019 - 1:19:28 AM
Long-term archiving on : Wednesday, December 9, 2015 - 10:43:36 AM

File

these_archivage_2607864o.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01195581, version 1

Citation

Marion Benetti. Les isotopes stables de l'eau en Atlantique Nord. Géochimie. Université Pierre et Marie Curie - Paris VI, 2015. Français. ⟨NNT : 2015PA066022⟩. ⟨tel-01195581⟩

Share

Metrics

Record views

389

Files downloads

1182