English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/15081
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Citado 82 veces en Web of Knowledge®  |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Título

Shallow-marine sediment cores record climate variability and earthquake activity off Lisbon (Portugal) for the last 2000 years

AutorAbrantes, F. F. G.; Lebreiro, S. M.; Rodrigues, T.; Gil, I. M.; Bartels-Jónsdóttir, H. B.; Oliveira, Paulo; Kissel, Catherine; Grimalt, Joan O.
Palabras claveClimatic variability
Earthquake activity
SST
Climatic change
NAO
Tagus River
Fecha de publicación17-feb-2005
EditorElsevier
CitaciónQuaternary Science Reviews 24(23-24): 2477-2494 (2005)
ResumenSea Surface Temperature (SST), river discharge and biological productivity have been reconstructed from a multi-proxy study of a high-temporal-resolution sedimentary sequence recovered from the Tagus deposition center off Lisbon (Portugal) for the last 2000 years. SST shows 2 °C variability on a century scale that allows the identification of the Medieval Warm Period (MWP) and the Little Ice Age (LIA).
High Iron (Fe) and fine-sediment deposition accompanied by high n-alkane concentrations and presence of freshwater diatoms during the LIA (1300–1900 AD) (Science 292 (2001) 662) suggest augmented river discharge, whereas higher total-alkenone concentrations point to increased river-induced productivity. During the MWP (550–1300 AD) (Science 292 (2001) 662) larger mean-grain size and low values of magnetic susceptibility, and concentrations of Fe, n-alkanes, and n-alcohols are interpreted to reflect decreased runoff. At the same time, increased benthic and planktonic foraminifera abundances and presence of upwelling related diatoms point to increased oceanic productivity. On the basis of the excellent match found between the negative phases of the North Atlantic Oscillation (NAO) index and the intensified Tagus River discharge observed for the last century, it is hypothesized that the increased influx of terrigenous material during the LIA reflects a negative NAO-like state or the occurrence of frequent extreme NAO minima. During the milder few centuries of the MWP, stronger coastal upwelling conditions are attributed to a persistent, positive NAO-like state or the frequent occurrence of extreme NAO maxima.
The peak in magnetic susceptibility, centered at 90 cm composite core depth (ccd), is interpreted as the result of the well-known 1755 AD Lisbon earthquake. The Lisbon earthquake and accompanying tsunami are estimated to have caused the loss of 39 cm of sediment (355 years of record—most of the LIA) and the instantaneous deposition of a 19-cm sediment bed.
Descripción18 pages, 12 figures.-- Printed version published Dec 2005.
Versión del editorhttp://dx.doi.org/10.1016/j.quascirev.2004.04.009
URIhttp://hdl.handle.net/10261/15081
DOI10.1016/j.quascirev.2004.04.009
ISSN0277-3791 (Print)
Aparece en las colecciones: (IDAEA) Artículos
Ficheros en este ítem:
No hay ficheros asociados a este ítem.
Mostrar el registro completo
 



NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.