Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization?

Journal of Oceanography
By: , and 

Links

Abstract

The subarctic North Pacific is a high nitrate-low chlorophyll (HNLC) region, where phytoplankton growth rates, especially those of diatoms, are enhanced when micronutrient Fe is added. Accordingly, it has been suggested that glacial Fe-laden dust might have increased primary production in this region. This paper reviews published palaeoceanographic records of export production over the last 800 kyrs from the open North Pacific (north of ∼35°N). We find different patterns of export production change over time in the various domains of the North Pacific (NW and NE subarctic gyres, the marginal seas and the transition zone). However, there is no compelling evidence for an overall increase in productivity during glacials in the subarctic region, challenging the paradigm that dust-born Fe fertilization of this region has contributed to the glacial draw down of atmospheric CO2. Potential reasons for the lack of increased glacial export production include the possibility that Fe-fertilization rapidly drives the ecosystem towards limitation by another nutrient. This effect would have been exacerbated by an even more stable mixed layer compared to today.

Publication type Article
Publication Subtype Journal Article
Title Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization?
Series title Journal of Oceanography
DOI 10.1023/B:JOCE.0000038326.73943.aa
Volume 60
Issue 1
Year Published 2004
Language English
Publisher Springer
Contributing office(s) Woods Hole Coastal and Marine Science Center
Description 15 p.
First page 189
Last page 203
Google Analytic Metrics Metrics page
Additional publication details