Issue 7, 2021

Atmospheric inputs of volcanic iron around Heard and McDonald Islands, Southern ocean

Abstract

Atmospheric deposition of iron to anemic waters in the Southern Ocean (SO) can relieve marine phytoplankton growth limitation. The northern Kerguelen plateau, in the iron-limited Indian sector of the SO, hosts vast annual spring blooms of marine phytoplankton, evidencing seasonal iron supply mechanisms. This study reports the first atmospheric measurements of iron concentration and solubility near and downwind of the volcanically active islands of Heard and McDonald Islands (HIMI) on the Kerguelen plateau. Using a combination of atmospheric tracers (radon and black carbon), air-mass back-trajectories, and trace metal ratios in aerosols, we detected emission from Heard Island in aerosols up to 500 km downwind from HIMI. The latter emissions were characterized by enrichment in molybdenum (Mo, ∼100 to 3000-fold), chromium (Cr) and nickel (Ni) (both ∼5 to 40-fold) in aerosols compared to Heard Island basaltic rocks. This phenomena reflects the greater volatility of Mo, Cr and Ni compared to the lithogenic reference trace metal aluminum (Al) under volcanic eruption atmospheric conditions. Our study highlights that volcanic emissions from Heard Island's main volcano, Big Ben, should be considered an additional source of atmospheric Fe supply to marine ecosystems near and downstream of the Kerguelen plateau, alongside other volcanic clusters in the Southern Hemisphere.

Graphical abstract: Atmospheric inputs of volcanic iron around Heard and McDonald Islands, Southern ocean

Supplementary files

Transparent peer review

To support increased transparency, we offer authors the option to publish the peer review history alongside their article.

View this article’s peer review history

Article information

Article type
Paper
Submitted
05 Jul 2021
Accepted
23 Aug 2021
First published
17 Sep 2021
This article is Open Access
Creative Commons BY-NC license

Environ. Sci.: Atmos., 2021,1, 508-517

Atmospheric inputs of volcanic iron around Heard and McDonald Islands, Southern ocean

M. M. G. Perron, B. C. Proemse, M. Strzelec, M. Gault-Ringold and A. R. Bowie, Environ. Sci.: Atmos., 2021, 1, 508 DOI: 10.1039/D1EA00054C

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements