Journal
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
Volume 119, Issue 6, Pages 4001-4028Publisher
AMER GEOPHYSICAL UNION
DOI: 10.1002/2013JC009355
Keywords
-
Categories
Funding
- US National Science Foundation [OCE-07529172, OCE-0327544, ANT-1040957]
- Los Angeles chapter of the ARCS Foundation
- Division Of Ocean Sciences
- Directorate For Geosciences [0752970] Funding Source: National Science Foundation
- Office of Polar Programs (OPP)
- Directorate For Geosciences [1040957] Funding Source: National Science Foundation
Ask authors/readers for more resources
A hydrographic data set collected in the region and season of Subantarctic Mode Water and Antarctic Intermediate Water (SAMW and AAIW) formation in the southeastern Pacific allows us to estimate the preformed properties of surface water detrained into these water masses from deep mixed layers north of the Subantarctic Front and Antarctic Surface Water south of the front. Using 10 measured seawater properties, we estimate: the fractions of SAMW/AAIW that originate as surface source waters, as well as fractions that mix into these water masses from subtropical thermocline water above and Upper Circumpolar Deep Water below the subducted SAMW/AAIW; ages associated with the detrained surface water; and remineralization and dissolution rates and ratios. The mixing patterns imply that cabbeling can account for similar to 0.005-0.03 kg m(-3) of additional density in AAIW, and similar to 0-0.02 kg m(-3) in SAMW. We estimate a shallow depth (similar to 300-700 m, above the aragonite saturation horizon) calcium carbonate dissolution rate of 0.4 +/- 0.2 mmol CaCO3 kg(-1) yr(-1), a phosphate remineralization rate of 0.031 +/- 0.009 mu mol P kg(-1) yr(-1), and remineralization ratios of P:N:-O-2:C-org of 1:(15.5 +/- 0.6):(143 +/- 10):(104 +/- 22) for SAMW/AAIW. Our shallow depth calcium carbonate dissolution rate is comparable to previous estimates for our region. Our -O-2:P ratio is smaller than many global averages. Our model suggests neglecting diapycnal mixing of preformed phosphate has likely biased previous estimates of -O-2:P and C-org:P high, but that the C-org:P ratio bias may have been counteracted by a second bias in previous studies from neglecting anthropogenic carbon gradients.
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