Browsing by Author "Gonzalez-Samperiz, Penelope"

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    The last deglaciation in the Picos de Europa National Park (Cantabrian Mountains, northern Spain)
    (2010) Moreno, Ana; Valero-Garces, Blas L.; Jimenez-Sanchez, Montserrat; Jose Dominguez-Cuesta, Maria; Pilar Mata, M.; Navas, Ana; Gonzalez-Samperiz, Penelope; Stoll, Heather; Farias, Pedro; Morellon, Mario; Pablo Corella, J.; Rico, Mayte
    A sedimentological and geochemical study of the Lago Enol sequence (Cantabrian Mountains, northern Spain), together with detailed geomorphological mapping, provides a first record of glacier evolution and climate change over the last 40 ka in the Picos de Europa National Park. The Enol glacier retreated from its maximum extent prior to 40 ka BP as demonstrated by the onset of proglacial lacustrine sedimentation in two glaciated depressions: the Comella hollow to the north (before 40 ka BP) and the Lago Enol (before 38 ka BP). These results support previous evidence that the maximum extent of southern European glaciers occurred earlier than in northern Europe. Alternation of homogeneous and laminated proglacial sediments during the glacier retreat illustrate a dynamic glacial evolution during the Marine Isotope Stage (MIS) 3 (40-26 ka BP). A slight warming is detected at 26 ka ago with the change from proglacial sediments (in a lake located in contact to the glacier) to glaciolacustrine sedimentation (in a non-contact or distal lake). Finally, the onset of organic-rich sediments took place at 18 ka ago. This last transition occurred in two phases, similarly to the North Atlantic Last Termination, suggesting a link between North Atlantic Deep Water formation oscillations and palaeohydrological variability in the Cantabrian Mountains. Copyright (C) 2009 John Wiley & Sons, Ltd.
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    The Medieval Climate Anomaly in the Iberian Peninsula reconstructed from marine and lake records
    (2012) Moreno, Ana; Perez, Ana; Frigola, Jaime; Nieto-Moreno, Vanesa; Rodrigo-Gamiz, Marta; Martrat, Belen; Gonzalez-Samperiz, Penelope; Morellon, Mario; Martin-Puertas, Celia; Pablo Corella, Juan; Belmonte, Anchel; Sancho, Carlos; Cacho, Isabel; Herrera, Gemma; Canals, Miguel; Grimalt, Joan O.; Jimenez-Espejo, Francisco J.; Martinez-Ruiz, Francisca; Vegas-Vilarrubia, Teresa; Valero-Garces, Blas L.
    Selected multi-proxy and accurately dated marine and terrestrial records covering the past 2000 years in the Iberian Peninsula (IP) facilitated a comprehensive regional paleoclimate reconstruction for the Medieval Climate Anomaly (MCA: 900-1300 AD). The sequences enabled an integrated approach to land-sea comparisons and, despite local differences and some minor chronological inconsistencies, presented clear evidence that the MCA was a dry period in the Mediterranean IP. It was a period characterized by decreased lake levels, more xerophytic and heliophytic vegetation, a low frequency of floods, major Saharan eolian fluxes, and less fluvial input to marine basins. In contrast, reconstruction based on sequences from the Atlantic Ocean side of the peninsula indicated increased humidity. The data highlight the unique characteristics of the MCA relative to earlier (the Dark Ages, DA: ca 500-900 years AD) and subsequent (the Little Ice Age, LIA: 1300-1850 years AD) colder periods. The reconstruction supports the hypothesis of Trouet et al. (2009), that a persistent positive mode of the North Atlantic Oscillation (NAO) dominated the MCA. (C) 2012 Elsevier Ltd. All rights reserved.