University of Tasmania
Browse

File(s) under permanent embargo

A Lagrangian biogeochemical study of an eddy in the Northeast Atlantic

journal contribution
posted on 2023-05-16, 23:45 authored by Jickells, TD, Liss, PS, Broadgate, W, Turner, S, Kettle, AJ, Read, J, Baker, K, Cardenas, LM, Carse, F, Hamren-Larssen, M, Spokes, L, Steinke, M, Thompson, A, Watson, A, Archer, SD, Bellerby, RGJ, Law, CS, Nightingale, PD, Liddicoat, MI, Widdicombe, CE, Andrew BowieAndrew Bowie, Gilpin, LC, Moncoiffe, G, Savidge, G, Preston, T, Hadziabdic, P, Frost, T, Upstill-Goddard, R, Pedros-Alio, C, Simo, R, Jackson, A, Allen, A, DeGrandpre, MD
We report the results of an experiment in the Northeast Atlantic in which sulphur hexafluoride (SF6) was released within an eddy and the behaviour of trace gases, nutrients and productivity followed within a Lagrangian framework over a period of 24 days. Measurements were also made in the air above the eddy in order to estimate air–sea exchange rates for some components. The physical, biological and biogeochemical properties of the eddy resemble those of other eddies studied in this area, suggesting that the results we report may be applicable beyond the specific eddy studied. During a period of low wind speed at the start of the experiment, we are able to quantitatively describe and balance the nutrient and carbon budgets for the eddy. We also report concentrations of various trace gases in the region which are similar to those observed in other studies and we estimate exchange rates for several trace gases. We show that the importance of gas exchange over other loss terms varies with time and also varies for the different gases. We show that the various trace gases considered (CO2, dimethyl sulphide (DMS), N2O, CH4, non-methane-hydrocarbons, methyl bromide, methyl iodide and volatile selenium species) are all influenced by physical and biological processes, but the overall distribution and temporal variability of individual gases are different to one another. A storm disrupted the stratification in the eddy during the experiment, resulting in enhanced nutrient supply to surface waters, enhanced gas exchange rates and a change in plankton community, which we quantify, although overall productivity was little changed. Emphasis is placed on the regularity of storms in the temperate ocean and the importance of these stochastic processes in such systems.

History

Publication title

Progress in Oceanography

Volume

76

Pagination

366-398

ISSN

0079-6611

Department/School

Institute for Marine and Antarctic Studies

Publisher

Pergamon-Elsevier Science Ltd.

Place of publication

Oxford, England

Rights statement

The definitive version is available at http://www.sciencedirect.com

Repository Status

  • Restricted

Socio-economic Objectives

Oceanic processes (excl. in the Antarctic and Southern Ocean)

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC