Climate change imprinting on stable isotopic compositions of high-elevation meteoric water cloaks past surface elevations of major orogens

Abstract

Research Article| June 01, 2011 Climate change imprinting on stable isotopic compositions of high-elevation meteoric water cloaks past surface elevations of major orogens Christopher J. Poulsen; Christopher J. Poulsen Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005, USA Search for other works by this author on: GSW Google Scholar M. Louise Jeffery M. Louise Jeffery Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Christopher J. Poulsen Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005, USA M. Louise Jeffery Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005, USA Publisher: Geological Society of America Received: 06 Jan 2011 Revision Received: 10 Feb 2011 Accepted: 14 Feb 2011 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2011 Geological Society of America Geology (2011) 39 (6): 595–598. https://doi.org/10.1130/G32052.1 Article history Received: 06 Jan 2011 Revision Received: 10 Feb 2011 Accepted: 14 Feb 2011 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Christopher J. Poulsen, M. Louise Jeffery; Climate change imprinting on stable isotopic compositions of high-elevation meteoric water cloaks past surface elevations of major orogens. Geology 2011;; 39 (6): 595–598. doi: https://doi.org/10.1130/G32052.1 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 Stable isotope paleoaltimetry has been widely used to estimate Cenozoic surface elevation of major orogens. The influence of global climate change on stable isotope paleoaltimetry is uncertain, with proposals that warming could cause either overestimates or underestimates of past surface elevations. In this study we increase atmospheric pCO2 by two and four times in an isotope-tracking atmospheric general circulation model to investigate the effect of global warming on oxygen isotopic compositions of precipitation (δ18Op) over the continents. As in other climate models, the response in the GENESIS version 3 model to global warming is an amplification of upper troposphere temperatures through enhanced infrared absorption and a reduction in the surface to upper-level temperature gradient. Due to the temperature dependence of isotopic fractionation, vapor δ18O (δ18Ov) follows suit, leading to a reduction in the surface to upper troposphere δ18Ov gradient. In regions of subsidence, including the major orogens and deserts, downward mixing of 18O-enriched vapor from the troposphere to the near surface further reduces the lapse rate of δ18Ov. As a consequence of these effects, the isotopic composition of precipitation in high-elevation regions, including the Tibetan Plateau, Rocky Mountains, European Alps, and Andean Plateau, increases by 3‰–6‰ relative to that at low elevations. Neglect of this climate effect on high-elevation δ18Op has likely led to underestimates of the surface elevation of Cenozoic orogens. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.