How well do global ocean biogeochemistry models simulate dissolved iron distributions?


Contact
Christoph.Voelker [ at ] awi.de

Abstract

Numerical models of ocean biogeochemistry are relied upon to make projections about the impact of climate change on marine resources and test hypotheses regarding the drivers of past changes in climate and ecosystems. In large areas of the ocean, iron availability regulates the functioning of marine ecosystems and hence the ocean carbon cycle. Accordingly, our ability to quantify the drivers and impacts of fluctuations in ocean ecosystems and carbon cycling in space and time relies on first achieving an appropriate representation of the modern marine iron cycle in models. When the iron distributions from thirteen global ocean biogeochemistry models are compared against the latest oceanic sections from the GEOTRACES programme we find that all models struggle to reproduce many aspects of the observed spatial patterns. Models that reflect the emerging evidence for multiple iron sources or subtleties of its internal cycling perform much better in capturing observed features than their simpler contemporaries, particularly in the ocean interior. We show that the substantial uncertainty in the input fluxes of iron results in a very wide range of residence times across models, which has implications for the response of ecosystems and global carbon cycling to perturbations. Given this large uncertainty, iron-fertilisation experiments based on any single current generation model should be interpreted with caution. Improvements to how such models represent iron scavenging and also biological cycling are needed to raise confidence in their projections of global biogeochemical change in the ocean.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Peer revision
ISI/Scopus peer-reviewed
Publication Status
Published
Eprint ID
39333
DOI 10.1002/2015GB005289

Cite as
Tagliabue, A. , Aumont, O. , DeAth, R. , Dunne, J. P. , Dutkiewicz, S. , Galbraith, E. , Misumi, K. , Moore, J. K. , Ridgwell, A. , Sherman, E. , Stock, C. , Vichi, M. , Völker, C. and Yool, A. (2015): How well do global ocean biogeochemistry models simulate dissolved iron distributions? , Global Biogeochemical Cycles, 30 (2), pp. 149-147 . doi: 10.1002/2015GB005289


Download
[img]
Preview
PDF
FeMIP_MS_REVISED_TRACK_final.pdf

Download (315kB) | Preview
Cite this document as:

Share


Citation

Research Platforms
N/A

Campaigns


Actions
Edit Item Edit Item