Silicon isotopes in Arctic and sub-Arctic glacial meltwaters: The role of subglacial weathering in the silicon cycle

Jade E. Hatton*, Katharine R. Hendry, Jonathan R. Hawkings, Jemma L. Wadham, Sophie Opfergelt, Tyler J. Kohler, Jacob C. Yde, Marek Stibal, Jakub D. Žárský

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)

4 Citations (Scopus)
142 Downloads (Pure)

Abstract

Glacial environments play an important role in high-latitude marine nutrient cycling, potentially contributing significant fluxes of silicon (Si) to the polar oceans, either as dissolved silicon (DSi) or as dissolvable amorphous silica (ASi). Silicon is a key nutrient in promoting marine primary productivity, contributing to atmospheric CO2 removal. We present the current understanding of Si cycling in glacial systems, focusing on the Si isotope (δ30Si) composition of glacial meltwaters. We combine existing glacial δ30Si data with new measurements from 20 subArctic glaciers, showing that glacial meltwaters consistently export isotopically light DSi compared with non-glacial rivers (+0.16 versus +1.38). Glacial δ30SiASi composition ranges from −0.05 to −0.86 but exhibits low seasonal variability. Silicon fluxes and δ30Si composition from glacial systems are not commonly included in global Si budgets and isotopic mass balance calculations at present. We discuss outstanding questions, including the formation mechanism of ASi and the export of glacial nutrients from fjords. Finally, we provide a contextual framework for the recent advances in our understanding of subglacial Si cycling and highlight critical research avenues for assessing potential future changes in these environments.

Original languageEnglish
Article number20190098
Number of pages27
JournalProceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Volume475
Issue number2228
DOIs
Publication statusPublished - 14 Aug 2019

Keywords

  • Glaciers and Ice Sheets
  • Silicon Cycle
  • Silicon Isotopes
  • Subglacial Weathering

Fingerprint Dive into the research topics of 'Silicon isotopes in Arctic and sub-Arctic glacial meltwaters: The role of subglacial weathering in the silicon cycle'. Together they form a unique fingerprint.

  • Projects

    ICY-LAB: Isotope CYcling in the LABrador Sea

    Hendry, K.

    1/07/1630/06/21

    Project: Research

  • Student Theses

    Silicon Cycling in Subglacial Environments: An Investigation into Glacial Silicon Isotope Systematics

    Author: Hatton, J., 25 Jun 2019

    Supervisor: Hendry, K. (Supervisor) & Wadham, J. (Supervisor)

    Student thesis: Doctoral ThesisDoctor of Philosophy (PhD)

    File

    Cite this