Coralline algal Mg-O bond strength as a marine pCO₂ proxy

Pauly, M., Kamenos, N. A. , Donohue, P. and LeDrew, E. (2015) Coralline algal Mg-O bond strength as a marine pCO₂ proxy. Geology, 43(3), pp. 267-270. (doi: 10.1130/G36386.1)

Abstract

Past ocean acidification recorded in the geological record facilitates the understanding of rates and influences of contemporary <i>p</i>CO₂ enrichment. Most pH reconstructions are made using boron, however there is some uncertainty associated with vital effects and isotopic fractionation. Here we present a new structural proxy for carbonate chemistry; Mg-O bond strength in coralline algae. Coralline algae were incubated in control (380 μatm <i>p</i>CO₂), moderate (750 μatm<i>p</i>CO₂), and high (1000 μatm <i>p</i>CO₂) acidification conditions for 24 months. Raman spectroscopy was used to determine skeletal Mg-O bond strength. There was a positive linear relationship between <i>p</i>CO₂ concentration and bond strength mediated by positional disorder in the calcite lattice when accounting for seasonal temperature. The structural preservation of the carbonate chemistry system in coralline algal high-Mg calcite represents an alternative approach to reconstructing marine carbonate chemistry. Significantly, it also provides an important mechanism for reconstructing historic atmospheric CO₂ concentrations.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Kamenos, Professor Nick and Donohue, Miss Penelope
• Authors: Pauly, M., Kamenos, N. A., Donohue, P., and LeDrew, E.
• College/School: College of Science and Engineering > School of Geographical and Earth Sciences
• Journal Name: Geology
• Publisher: Geological Society of America
• ISSN: 0091-7613
• ISSN (Online): 1943-2682
• Copyright Holders: Copyright © 2015 The Authors
• First Published: First published in Geology 43(3):267-270
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
63612	1	Abrupt Ocean Acidification Events	Nicholas Kamenos	Natural Environment Research Council (NERC)	NE/H017356/1	SCHOOL OF GEOGRAPHICAL & EARTH SCIENCES