Ice sheets as a missing source of silica to the polar oceans
Details
Serval ID
serval:BIB_E8B2AF3CE690
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Ice sheets as a missing source of silica to the polar oceans
Journal
Nature Communications
ISSN
2041-1723
Publication state
Published
Issued date
25/01/2017
Peer-reviewed
Oui
Volume
8
Number
1
Language
english
Abstract
Ice sheets play a more important role in the global silicon cycle than previously appreciated. Input of dissolved and amorphous particulate silica into natural waters stimulates the growth of diatoms. Here we measure dissolved and amorphous silica in Greenland Ice Sheet meltwaters and icebergs, demonstrating the potential for high ice sheet export. Our dissolved and amorphous silica flux is 0.20 (0.06–0.79) Tmol year−1, ∼50% of the input from Arctic rivers. Amorphous silica comprises >95% of this flux and is highly soluble in sea water, as indicated by a significant increase in dissolved silica across a fjord salinity gradient. Retreating palaeo ice sheets were therefore likely responsible for high dissolved and amorphous silica fluxes into the ocean during the last deglaciation, reaching values of ∼5.5 Tmol year−1, similar to the estimated export from palaeo rivers. These elevated silica fluxes may explain high diatom productivity observed during the last glacial–interglacial period.
Keywords
Cryospheric science, Element cycles, Geochemistry, Marine chemistry
Pubmed
Web of science
Open Access
Yes
Create date
29/08/2024 10:03
Last modification date
25/11/2024 16:50