Browsing by Author "Moreno, Ana"

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    A 7000‐year high‐resolution lake sediment record from coastal central Chile (Lago Vichuquén, 34°S): implications for past sea level and environmental variability
    (2017) Frugone, M. J.; Latorre H., Claudio; Giralt, Santiago; Polanco Martínez, Josué; Bernárdez, Patricia; Oliva Urcía, Belén; Maldonado, Antonio; Carrevedo, María Laura; Moreno, Ana; Delgado Huertas, Antonio; Prego, Ricardo; Barreiro Lostres, Fernando; Valero Garcés, Blas
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    A multi-dating approach to age-modelling long continental records : The 135 ka El Canizar de Villarquemado sequence (NE Spain)
    (2019) Valero Garcés, Blas Lorenzo; González Samperiz, Penelope; Gil Romera, Graciela; Benito, Blas Manuel; Moreno, Ana; Oliva Urcia, Belén; Aranbarri, Josu; García Prieto, Eduardo; Frugone Álvarez, Matías; Morellón, Mario; Arnold, Lee J.; Demuro, Martina; Hardiman, M.; Blockley, Simon; Lane, C. S.
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    Hydrological change in Southern Europe responding to increasing North Atlantic overturning during Greenland Stadial 1
    (2015) Bartolome, Miguel; Moreno, Ana; Sancho, Carlos; Stoll, Heather M.; Cacho, Isabel; Spoetl, Christoph; Belmonte, Anchel; Edwards, R. Lawrence; Cheng, Hai; Hellstrom, John C.
    Greenland Stadial 1 (GS-1) was the last of a long series of severe cooling episodes in the Northern Hemisphere during the last glacial period. Numerous North Atlantic and European records reveal the intense environmental impact of that stadial, whose origin is attributed to an intense weakening of the Atlantic Meridional Overturning Circulation in response to freshening of the North Atlantic. Recent high-resolution studies of European lakes revealed a mid-GS-1 transition in the climatic regimes. The geographical extension of such atmospheric changes and their potential coupling with ocean dynamics still remains unclear. Here we use a subdecadally resolved stalagmite record from the Northern Iberian Peninsula to further investigate the timing and forcing of this transition. A solid interpretation of the environmental changes detected in this new, accurately dated, stalagmite record is based on a parallel cave monitoring exercise. This record reveals a gradual transition from dry to wet conditions starting at 12,500 y before 2000 A. D. in parallel to a progressive warming of the subtropical Atlantic Ocean. The observed atmospheric changes are proposed to be led by a progressive resumption of the North Atlantic convection and highlight the complex regional signature of GS-1, very distinctive from previous stadial events.
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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.