Warm and cold wet states in the western United States during the Pliocene–Pleistocene

Abstract

Research Article| February 15, 2018 Warm and cold wet states in the western United States during the Pliocene–Pleistocene Daniel E. Ibarra; Daniel E. Ibarra * 1Department of Earth System Science, Stanford University, Stanford, California 94305, USA *E-mail: [e-mail] Search for other works by this author on: GSW Google Scholar Jessica L. Oster; Jessica L. Oster 2Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee 37240, USA Search for other works by this author on: GSW Google Scholar Matthew J. Winnick; Matthew J. Winnick 3Department of Geological Sciences, Stanford University, Stanford, California 94305, USA Search for other works by this author on: GSW Google Scholar Jeremy K. Caves Rugenstein; Jeremy K. Caves Rugenstein 1Department of Earth System Science, Stanford University, Stanford, California 94305, USA4Department of Earth Sciences, ETH Zürich, 8092 Zürich, Switzerland Search for other works by this author on: GSW Google Scholar Michael P. Byrne; Michael P. Byrne 5Institute for Atmospheric and Climate Science, Department of Environmental Systems Science, ETH Zürich, 8092 Zürich, Switzerland6Space and Atmospheric Physics Group, Department of Physics, Imperial College London, London SW7 2AZ, UK Search for other works by this author on: GSW Google Scholar C. Page Chamberlain C. Page Chamberlain 1Department of Earth System Science, Stanford University, Stanford, California 94305, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Daniel E. Ibarra * 1Department of Earth System Science, Stanford University, Stanford, California 94305, USA Jessica L. Oster 2Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee 37240, USA Matthew J. Winnick 3Department of Geological Sciences, Stanford University, Stanford, California 94305, USA Jeremy K. Caves Rugenstein 1Department of Earth System Science, Stanford University, Stanford, California 94305, USA4Department of Earth Sciences, ETH Zürich, 8092 Zürich, Switzerland Michael P. Byrne 5Institute for Atmospheric and Climate Science, Department of Environmental Systems Science, ETH Zürich, 8092 Zürich, Switzerland6Space and Atmospheric Physics Group, Department of Physics, Imperial College London, London SW7 2AZ, UK C. Page Chamberlain 1Department of Earth System Science, Stanford University, Stanford, California 94305, USA *E-mail: [e-mail] Publisher: Geological Society of America Received: 05 Dec 2017 Revision Received: 16 Jan 2018 Accepted: 24 Jan 2018 First Online: 15 Feb 2018 Online Issn: 1943-2682 Print Issn: 0091-7613 © 2018 Geological Society of America Geology (2018) 46 (4): 355–358. https://doi.org/10.1130/G39962.1 Article history Received: 05 Dec 2017 Revision Received: 16 Jan 2018 Accepted: 24 Jan 2018 First Online: 15 Feb 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Daniel E. Ibarra, Jessica L. Oster, Matthew J. Winnick, Jeremy K. Caves Rugenstein, Michael P. Byrne, C. Page Chamberlain; Warm and cold wet states in the western United States during the Pliocene–Pleistocene. Geology 2018;; 46 (4): 355–358. doi: https://doi.org/10.1130/G39962.1 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 size distribution of lakes records the competition between precipitation delivery and evaporation. Lakes were abundant in the terminally draining basins of the western United States (USA) during both the colder-than-preindustrial latest Pleistocene glacial period (ca. 14–29 ka) and the warmer-than-preindustrial mid-Pliocene (ca. 2.9–3.3 Ma). To understand the hydroclimatic conditions that permitted lakes, we couple lake mass balance equations with a water and energy balance framework (sensu Budyko). Further, we compare paleo-lake area distributions to forward-modeled lake areas using climate model simulations of the Last Glacial Maximum (LGM, 19–26 ka) and mid-Pliocene. We conclude that both warmer- and colder-than-modern periods of the Pliocene–Pleistocene resulted in wetter-than-modern conditions in the terminally draining basins of the western USA through similar mechanisms. Specifically, the presence of lakes during the LGM reflects increased precipitation in addition to decreased evaporative demand. In the southern Great Basin, LGM lakes require large increases in precipitation across the region. During the mid-Pliocene, increased evaporative demand necessitated increased precipitation to maintain lakes. Further, the increase in precipitation and dominantly southwestern distribution of mid-Pliocene lake deposits is consistent with proposed mean "El Niño–like" conditions altering regional hydroclimate during this period. These observations suggest that during interglacial periods, the western USA resides within a local aridity maximum, and both long-term increases and decreases in global temperatures have been associated with wetter conditions across much of the western USA in the past. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.