Journal
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
Volume 118, Issue 5, Pages 2547-2564Publisher
AMER GEOPHYSICAL UNION
DOI: 10.1002/jgrc.20181
Keywords
phosphate; biological pump; Southern Ocean; data assimilation; ocean model; biological production
Categories
Funding
- NSF [OCE-1131768, ATM-0854711]
- ARC [DP120100674]
- [OCE-1131548]
- Directorate For Geosciences [1131768] Funding Source: National Science Foundation
- Div Atmospheric & Geospace Sciences
- Directorate For Geosciences [0854711] Funding Source: National Science Foundation
- Division Of Ocean Sciences [1131768] Funding Source: National Science Foundation
Ask authors/readers for more resources
We present a data-assimilated model of the ocean's phosphorus cycle that is constrained by climatological phosphate, temperature, salinity, sea-surface height, surface heat and freshwater fluxes, as well as chlorofluorocarbon-11(CFC-11) and natural C-14. Export production is estimated to be 5.82.0x10(12) mol P/yr of which (266)% originates in the Southern Ocean (SO) south of 40 degrees S. The biological pump efficiency, defined as the proportion of the ocean's phosphate inventory that is regenerated, is (397)%. Dividing the SO south of 40 degrees S into a sub-Antarctic zone (SANTZ) and an Antarctic zone (ANTZ) separated by the latitude of maximum Ekman divergence, we estimate that the SANTZ and ANTZ account, respectively, for (235)% and (3 +/- 1)% of global export production, (17 +/- 4)% and (3 +/- 1)% of the regenerated nutrient inventory, and (31 +/- 1)% and (43 +/- 5)% of the preformed nutrient inventory. Idealized SO nutrient depletion experiments reveal a large-scale transfer of nutrients into circumpolar and deep waters and from the preformed to the regenerated pool. In accord with the concept of the biogeochemical divide, we find that nutrient drawdown in the ANTZ is more effective than in the SANTZ for increasing the efficiency of the biological pump, while having a smaller impact on production in regions north of 40 degrees S. Complete SO nutrient drawdown would allow the biological pump to operate at 94% efficiency by short circuiting the transport of nutrients in northward Ekman currents, leading to a trapping of nutrients in circumpolar and deep waters that would decrease production outside the SO by approximately 44% while increasing it in the SO by more than 725%.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available