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Se analiza la estimación de las paleotemperaturas del agua superficial del Golfo de León, desarrollada a través de la técnica de los análogos modernos, método importante para la reconstrucción de las corrientes que afectan a esa zona. Planktonic foraminifer assemblages from core PRGL1-4 have been studied to reconstruct sea surface temperatures (SST) in the Gulf of Lions during Marine Isotope Stages 6 and 7 based on the modern analog technique. This method consists of a comparison between core and modern sample assemblages assuming that similar planktonic foraminifer assemblages develop under the same ecological conditions and thatforaminifer ecological preferences have not changed in time. During stage 6 (glacial) a strong millennial variability is observed in SST, whereas in stage 7 (interglacial) the astronomical forcing controls SST. These features have been already reported in temperature records from other areas out of the MediterraneanSea, which means that SST in the Gulf of Lions during stages 6 and 7 was influenced by global climatechanges. Moreover, some differences exist between paleotemperature records from different areas in the Mediterranean region. In the Gulf of Lions temperature records are more extreme since this area is directly influenced by Mistral and Tramontane winds, which cause important water cooling during cold periods.Furthermore, this study suggests that seasonality in the Gulf of Lions is not influenced by Northern Hemisphere summer insolation.

Se estudia la paleoclimatología en el Mar de Alborán utilizano la técnica de los análogos modernos. Planktonic foraminifers from core ODP site 977a have been studied to estimate sea surface temperatures (SST) inthe Alboran Sea between 245 and 145 kyr. Similar studies have been performed in this basin but only for the last150 kyr (Perez-Folgado et al., 2004). SSTs in this basin are highly controlled by the atlantic superficial incoming fluxthrough the Gibraltar Strait. In this study we estimate paleotemperatures with the modern analog techniquewhich consists on a comparison between core and modern sample assemblages. This method assumes thatsimilar planktonic foraminifer assemblages develop under the same ecological conditions and that foraminiferecological preferences have not changed in time. This technique also provides a dissimilarity index (between 0 and1) which depends on the liability of the estimation obtained. In this study we used Kallel et al. (1997) moderndatabase which contains a total of 253 samples, 123 from the North Atlantic and 130 from the MediterraneanSea. For the estimations we used PaleoAnalogs 2.0, computer program developed by the University of Salamanca(Theron et al., 2004). A small SST difference exists between substages 7.3, 7.2 and 7.1. Important millennialcyclicities (7.4, 5.6 and 4.6 kyr) occur during the whole studied period, both in warm and cold intervals, althoughchanges seem to be broader during cold ones. Seasonality is higher during the warmer substages, 7.5 and 7.3,whereas it is smaller during the strong Northern Hemisphere summer insolation minimum in substage 7.4.