Global perturbation of the carbon cycle at the onset of the Miocene Climatic Optimum

Research Article| February 01, 2015 Global perturbation of the carbon cycle at the onset of the Miocene Climatic Optimum Ann Holbourn; Ann Holbourn 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Search for other works by this author on: GSW Google Scholar Wolfgang Kuhnt; Wolfgang Kuhnt 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Search for other works by this author on: GSW Google Scholar Karlos G.D. Kochhann; Karlos G.D. Kochhann 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Search for other works by this author on: GSW Google Scholar Nils Andersen; Nils Andersen 2Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts University, D-24118 Kiel, Germany Search for other works by this author on: GSW Google Scholar K.J. Sebastian Meier K.J. Sebastian Meier 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Search for other works by this author on: GSW Google Scholar Author and Article Information Ann Holbourn 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Wolfgang Kuhnt 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Karlos G.D. Kochhann 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Nils Andersen 2Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts University, D-24118 Kiel, Germany K.J. Sebastian Meier 1Institute of Geosciences, Christian-Albrechts University, D-24118 Kiel, Germany Publisher: Geological Society of America Received: 27 Sep 2014 Revision Received: 18 Nov 2014 Accepted: 21 Nov 2014 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2015 Geological Society of America Geology (2015) 43 (2): 123–126. https://doi.org/10.1130/G36317.1 Article history Received: 27 Sep 2014 Revision Received: 18 Nov 2014 Accepted: 21 Nov 2014 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Ann Holbourn, Wolfgang Kuhnt, Karlos G.D. Kochhann, Nils Andersen, K.J. Sebastian Meier; Global perturbation of the carbon cycle at the onset of the Miocene Climatic Optimum. Geology 2015;; 43 (2): 123–126. doi: https://doi.org/10.1130/G36317.1 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 The Miocene Climatic Optimum (MCO; ca. 17–14.7 Ma) represents one of several major interruptions in the long-term cooling trend of the past 50 m.y. To date, the processes driving high-amplitude climate variability and sustaining global warmth during this remarkable interval remain highly enigmatic. We present high-resolution benthic foraminiferal and bulk carbonate stable isotope records in an exceptional, continuous, carbonate-rich sedimentary archive (Integrated Ocean Drilling Program Site U1337, eastern equatorial Pacific Ocean), which offer a new view of climate evolution over the onset of the MCO. A sharp decline in δ18O and δ13C at ca. 16.9 Ma, contemporaneous with a massive increase in carbonate dissolution, demonstrates that abrupt warming was coupled to an intense perturbation of the carbon cycle. The rapid recovery in δ13C at ca. 16.7 Ma, ∼250 k.y. after the beginning of the MCO, marks the onset of the first carbon isotope maximum within the long-lasting "Monterey Excursion." These results lend support to the notion that atmospheric pCO2 variations drove profound changes in the global carbon reservoir through the MCO, implying a delicate balance between changing CO2 fluxes, rates of silicate weathering, and global carbon sequestration. Comparison with a high-resolution δ13C record spanning the onset of the Cretaceous Oceanic Anoxic Event 1a (∼120 m.y. ago) reveals common forcing factors and climatic responses, providing a long-term perspective to understand climate–carbon cycle feedbacks during warmer periods of Earth's climate with markedly different atmospheric CO2 concentrations. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.