Open Access Repository

Non-monotonic response of primary production and export to changes in mixed-layer depth in the Southern Ocean

Llort, J ORCID: 0000-0003-1490-4521, Levy, M, Sallee, JB and Tagliabue, A 2019 , 'Non-monotonic response of primary production and export to changes in mixed-layer depth in the Southern Ocean' , Geophysical Research Letters , pp. 1-22 , doi:

PDF (Accepted version)
131622 - Non-mo...pdf | Download (1MB)

| Preview


Ongoing and future changes in wind and temperature are predicted to alter upper ocean vertical mixing across the Southern Ocean. How these changes will affect primary production (PP) remains unclear as mixing influences the two controlling factors: light and iron. We used a large ensemble of 1D‐biogeochemical model simulations to explore the impacts of changes in mixed‐layer depths (MLD) on PP in the Southern Ocean. In summer, shoaling MLD always reduced depth‐integrated PP, despite increasing production rates. In winter, shoaling mixed‐layers had a two‐staged impact: for moderate shoaling PP increased as light conditions improved, but more pronounced shoaling decreased iron supply, which reduced PP. The fraction of PP exported below 100m also presented a non‐monotonic behavior. This suggests a potential future shift from a situation where reduced winter mixing increases PP and export, to a situation where PP and export may collapse if the ML shoals above a threshold depth.

Item Type: Article
Authors/Creators:Llort, J and Levy, M and Sallee, JB and Tagliabue, A
Keywords: phytoplankton, Southern Ocean, mixed layer depth, climate change
Journal or Publication Title: Geophysical Research Letters
Publisher: Amer Geophysical Union
ISSN: 0094-8276
DOI / ID Number:
Copyright Information:

Copyright 2019 American Geophysical Union

Related URLs:
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page