Geographical analysis of the Northern Atlantic continental climate changes during the Weichselian Late-Glacial

• Main Author: Soto, Didier
• Other Authors: Environnement, Ville, Société (EVS), École normale supérieure - Lyon (ENS Lyon)-École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom Paris (IMT)-Institut Mines-Télécom Paris (IMT)-Université Lumière - Lyon 2 (UL2)-Université Jean Moulin - Lyon 3 (UJML), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-École Nationale des Travaux Publics de l'État (ENTPE)-École nationale supérieure d'architecture de Lyon (ENSAL)-Centre National de la Recherche Scientifique (CNRS), Université Jean Moulin Lyon 3, Jacques Comby
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2013
• Subjects: climate changes; Weichselian Late-Glacial; North Atlantic area; air masses ‘dynamic; paleoenvironments; thermal quantifications; GIS.; changements climatiques; Tardiglaciaire würmien; espace Nord-Atlantique; dynamique des masses d’air; paléoenvironnements; quantifications thermiques; SIG.; [SHS.GEO]Humanities and Social Sciences/Geography; [SDE.MCG]Environmental Sciences/Global Changes; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; North Atlantic
• Online Access: https://hal.science/tel-01316582; https://hal.science/tel-01316582/document; https://hal.science/tel-01316582/file/SOTO%20D.%20%282012%29%20-%20Th%C3%A8se.pdf

This thesis proposes a multi-criterion analysis, from which have been displayed the bioclimatic characteristics of the Late-Glacial stadials and interstadials. Mapping data, mainly obtained through crossing three quantification methods, lead to the opposition of distinct paleoclimatic domains in the study area. The relative synchronism of the studied geochronologies highlights the central position of the Northern Atlantic Ocean in the determination of Late-Glacial abrupt climatic changes. However, a review of the main scenarios of oceanographic forcing identifies some of their limitations in the triggering, self-maintenance as well as the teleconnection of the climatic signal. The exploration of other physical mechanisms allows validating the hypothesis by which the air masses’dynamic is an essential component in the forcing of abrupt climatic events. However, the usual theoretical model of atmospheric circulation can not accurately reconstruct the paleoclimatic dynamic of Late-Glacial events. One of the main innovations of this thesis is therefore to experiment a general circulation model, the Mobile Polar High’s one, which provides a comprehensive explanation of climate changes by determining two distinct modes of aerologic circulation (fast and semi-fast). The advantage of this model lies in its ability to analyze a relevant diversity of paleoenvironmental changes in North America and Eurasia during the study period. Cette thèse propose une analyse multicritères de 686 sites d’étude, à partir de laquelle sont géovisualisées les caractéristiques bioclimatiques des stades et interstades du Tardiglaciaire. La cartographie des données obtenues, principalement grâce au croisement de trois méthodes de quantification, permet d’opposer plusieurs domaines paléoclimatiques distincts au sein de l’aire d’étude. Le synchronisme relatif des géochronologies étudiées met en avant la position centrale de l’Océan Atlantique Nord dans la détermination des changements climatiques abrupts de la période. Toutefois, le réexamen ...