Postglacial changes in El Niño and La Niña behavior

Research Article| January 01, 2010 Postglacial changes in El Niño and La Niña behavior Matthew C. Makou; Matthew C. Makou * 1Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA *Current address: Byrd Polar Research Center, The Ohio State University, 1090 Carmack Road, Scott Hall 108, Columbus, Ohio 43210, USA; E-mail: makou.1@osu.edu. Search for other works by this author on: GSW Google Scholar Timothy I. Eglinton; Timothy I. Eglinton 2Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Search for other works by this author on: GSW Google Scholar Delia W. Oppo; Delia W. Oppo 1Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Search for other works by this author on: GSW Google Scholar Konrad A. Hughen Konrad A. Hughen 2Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Search for other works by this author on: GSW Google Scholar Geology (2010) 38 (1): 43–46. https://doi.org/10.1130/G30366.1 Article history received: 06 May 2009 rev-recd: 25 Jul 2009 accepted: 28 Jul 2009 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Matthew C. Makou, Timothy I. Eglinton, Delia W. Oppo, Konrad A. Hughen; Postglacial changes in El Niño and La Niña behavior. Geology 2010;; 38 (1): 43–46. doi: https://doi.org/10.1130/G30366.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Paleoclimate reconstructions suggest distinctive changes in the El Niño–Southern Oscillation (ENSO), the dominant mode of tropical climate variability, over the last glacial cycle and throughout the Holocene. However, to the best of our knowledge, no studies provide parallel reconstructions of warm (El Niño) and cold (La Niña) phase variability, thus precluding distinction between variations in ENSO activity and the mean state of the tropical Pacific. Here we provide the first such records, generated using molecular organic geochemical proxies in a sediment core from the Peru margin region. The opposing influences of El Niño and La Niña on coastal upwelling and phytoplankton community structure produce distinct sedimentary sterol records describing the evolution of each ENSO phase. We document changes in surface ocean productivity on the Peru margin over the past 16 ka that indicate enhanced La Niña–like conditions alone during deglaciation, but concomitant increases in both El Niño and La Niña activity during the past 2 ka. We propose that the preponderance of La Niña–like conditions prior to 11.5 ka reflects the influence of waning glacial boundary conditions. By contrast, warm and cold phase covariability during the late Holocene suggests centennial-scale changes in ENSO activity, rather than the Pacific mean state, driven by tropical insolation. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.