Reconstruction of ocean and atmospheric circulation using isotopic signals recorded in massive corals from the Subtropical North Atlantic.

• Main Author: Desenfant, Fabrice
• Other Authors: Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de droit, d'économie et des sciences - Aix-Marseille III, CAMOIN GILBERT([e-mail])
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2004
• Subjects: Coral; Lead; Lead and Oxygen stable isotopes; Caribbean Sea; Subtropical North Atlantic Ocean; Endolithic micro-organisms; North Atlantic Oscillation; Mer des Caraïbes; Atlantique Nord Subtropical; Endolithes; Atmosphère; Océan; Oscillation Nord Atlantique; Coraux; Plomb; Isotopes stables du Plomb et de l'Oxygène; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; Pacific; Renaud; Sherrell; North Atlantic; North Atlantic oscillation
• Online Access: https://theses.hal.science/tel-00007682; https://theses.hal.science/tel-00007682/document; https://theses.hal.science/tel-00007682/file/tel-00007682.pdf

Rapporteurs : Christian DULLO, Professeur, IFM GEOMAR Kiel, Allemagne Renaud FICHEZ, Directeur de Recherche IRD, Centre d'Océanologie de Marseille Robert SHERRELL, Professeur ,Université de Rutgers, USA Examinateurs : Gilbert CAMOIN, Chargé de Recherche CNRS, CEREGE, Directeur de Thèse Francis GROUSSET, Directeur de Recherche, Université Bordeaux I Bruno HAMELIN, Professeur Université Aix-Marseille III, CEREGE Alexandre ROMANA, Directeur Département Env. Littoral, IFREMER-Toulon Alain VERON, Chargé de Recherche CNRS, CEREGE, co-directeur de Thèse The main purpose for this study is to reconstruct atmospheric and oceanic transport of pollutant lead in relation to climate variability in the subtropical North Atlantic during the XXth. century. This shall be performed using geochemical coral records and anthropogenic lead emission archives. We did first quantify the relative impact of the main anthropogenic sources to Caribbean corals (Mona Island and Martinique) with lead and its stable isotope (low level analysis by thermal ionisation mass spectrometry). Data show the capacity of corals to faithfully record input from industrialized continental sources (Northern and Central America, Western Europe) as well as meteorological events such as hurricanes. This high resolution study evidence the role of climate oscillations such as the NAO on the distribution of continental pollutants into oceanic surface waters. Discrepancies between the transient pollutant lead emission and its record inot corals from different locations in the Western North Atlantic did strongly suggest a significant control of oceanic circulation on lead distribution. Surface Seawater Temperature anomalies as recorded by Δ18O do evidence the seasonal impact of the Pacific meteorological indices (ENSO-PDO) on the North Atlantic circulation. KEY WORDS : Coral, Lead, Lead and Oxygen stable isotopes, Caribbean Sea, Subtropical North Atlantic Ocean, Endolithic micro-organisms, Atmosphere, Ocean, North Atlantic Oscillation. L'objectif de cette étude ...