Relationship between mechanical erosion and atmospheric CO2 consumption in the New Zealand Southern Alps

Abstract

Research Article| October 01, 2003 Relationship between mechanical erosion and atmospheric CO2 consumption in the New Zealand Southern Alps Andrew D. Jacobson; Andrew D. Jacobson 1Department of Geological Sciences, University of Michigan, 425 East University Avenue, Ann Arbor, Michigan 48109, USA Search for other works by this author on: GSW Google Scholar Joel D. Blum Joel D. Blum 1Department of Geological Sciences, University of Michigan, 425 East University Avenue, Ann Arbor, Michigan 48109, USA Search for other works by this author on: GSW Google Scholar Geology (2003) 31 (10): 865–868. https://doi.org/10.1130/G19662.1 Article history received: 11 Mar 2003 rev-recd: 05 Jun 2003 accepted: 06 Jun 2003 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Andrew D. Jacobson, Joel D. Blum; Relationship between mechanical erosion and atmospheric CO2 consumption in the New Zealand Southern Alps. Geology 2003;; 31 (10): 865–868. doi: https://doi.org/10.1130/G19662.1 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 To examine the influence of mountain uplift on the long-term carbon cycle, we used geochemical, hydrologic, and suspended-load data for 12 streams draining the New Zealand Southern Alps to quantify rates of erosion, weathering, and atmospheric CO2 consumption. Rapid uplift in the western Southern Alps elevates mechanical erosion rates by a factor of ∼13 relative to those on the tectonically stable eastern side [125 × 108 vs. 9.4 × 108 g/(km2·yr), respectively]. Similarly, the average chemical weathering rate is ∼5 times higher on the western compared to eastern side of the mountain range [9.8 × 107 vs. 2.0 × 107 g/(km2·yr), respectively]. However, because the proportion of stream-water Ca2+ and Mg2+ from carbonate weathering increases as the rate of mechanical erosion increases, the long-term atmospheric CO2 consumption rate on the western side is ∼2 times higher than that on the eastern side [14 × 104 vs. 6.9 × 104 mol/(km2·yr), respectively] and only ∼1.5 times higher than the global mean value [∼9 × 104 mol/(km2·yr)]. Data for major world rivers (including Himalayan rivers) provide a consistent interpretation regarding the relationship between mechanical erosion intensity and the ratio of silicate to carbonate weathering. Thus, we conclude that mountain building increases atmospheric CO2 consumption rates by only a factor of ∼2, which is much lower than previous estimates. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.