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Sea level and climate changes during OIS 5e in the Western Mediterranean

Departamento de Geología, Edificio Ciencias, Universidad de Alcalá, 28871-Alcalá de Henares, Spain; Departamento de Geología, Facultad de Ciencias, Universidad de Salamanca, 37008-Salamanca, Spain; Departamento de Geología, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal, 2, 28006-Madrid, Spain; Université du Québec à Montréal, GEOTOP-UQAM, Montréal, QC, Canada H3C 3P8; Departamento de Estratigrafía-UCM and Instituto de Geología Económica-CSIC, Universidad Complutense, 28040-Madrid, Spain; Departamento de Geología, Universidad de Salamanca, Escuela Politécnica Superior de Avila, 05003-Avila, Spain; Departamento de Ciencias Analíticas, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, 28040-Madrid, Spain
Geomorphology (Impact Factor: 2.58). 01/2009; 104:22-37. DOI: 10.1016/j.geomorph.2008.05.027
Source: OAI

ABSTRACT Palaeontological, geomorphological and sedimentological data supported by isotopic dating on Oxygen Isotopic Stage (OIS) 5e deposits from the Spanish Mediterranean coast, are interpreted with the aim of reconstructing climatic instability in the Northern Hemisphere. Data point to marked climatic instability during the Last Interglacial (OIS 5e), with a change in meteorological conditions and, consequently, in the sedimentary environment. The oolitic facies generated during the first part of OIS 5e (ca. 135 kyr) shift into reddish conglomeratic facies during the second part (ca. 117 kyr). Sea surface Temperature (SST) and salinity are interpreted mainly on the basis of warm Senegalese fauna, which show chronological and spatial differential distribution throughout the Western Mediterranean. Present hydrological and meteorological conditions are used also as modern analogues to reconstruct climatic variability throughout the Last Interglacial, and this variability is interpreted within the wider framework of the North Atlantic record. All the available data indicate an increase in storminess induced by an increase in the influence of north-westerlies, a slight drop of SST in the northern Western Mediterranean, and an important change in meteorological conditions at the end of OIS 5e (117 kyr). These changes correlate well with the decrease in summer insolation and with the climatic instability recorded in North Atlantic high latitudes.

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