Atlantic Multidecadal Oscillation (AMO) forcing on the late Holocene Cauca paleolake dynamics, northern Andes of Colombia
J. I. Martínez1, S. Obrochta2, Y. Yokoyama3, and R. W. Battarbee41Department Ciencias de la Tierra, Universidad EAFIT, Area de Ciencias del Mar, Medellín, Colombia 2Faculty of International Resources Science, Akita University, Akita, Japan 3Atmospheric and Ocean Research Institute, University of Tokyo, Tokyo, Japan 4ECRC, University College London, London, UK
Received: 26 Mar 2015 – Accepted for review: 29 Apr 2015 – Discussion started: 01 Jul 2015
Abstract. The Atlantic Multidecadal Oscillation (AMO), is a major driving climate mechanism, in the eastern Caribbean Sea and the South Atlantic Ocean in relation to the dynamics of the South American Monsoon System (SAMS) for the late Holocene. Here we document the AMO signal in the San Nicolás-1 core of the Cauca paleolake (Santa Fé–Sopetrán Basin) in the northern Andes. Wavelet spectrum analysis of the gray scale of the San Nicolás-1 core provides evidence for a 70 yr AMO periodicity for the 3750 to 350 yr BP time interval, whose pattern is analogous to the one documented for the Cariaco Basin. This supports a possible correlation between enhanced precipitation and ENSO variability with a positive AMO phase during the 2000 to 1500 yr BP interval, and its forcing role on the Cauca ria lake deposits, which led to increased precipitation and to the transition from a igapo (black water) to a varzea (white water) environment ca. 3000 yr BP.
Martínez, J. I., Obrochta, S., Yokoyama, Y., and Battarbee, R. W.: Atlantic Multidecadal Oscillation (AMO) forcing on the late Holocene Cauca paleolake dynamics, northern Andes of Colombia, Clim. Past Discuss., 11, 2649-2664, doi:10.5194/cpd-11-2649-2015, 2015.