Wintertime phytoplankton bloom in the subarctic Pacific supported by continental margin iron
Figure S1: FeKa maps through data analysis steps for a representative sample (96006p, OSP, 71m) mapped in July 2003. (103.5Kb)
Figure S2: Ti XRF map of SOFeX mesh blank showing Ti threshold (10th percentile) in white, outlining the “hole” regions. (198.6Kb)
Figure S4: Determination of Fe noise function using sample Jul96006p (OSP, 71m) and Cr as a noise diagnostic. (88.48Kb)
Lam, Phoebe J.
Bishop, James K. B.
Henning, Cara C.
Marcus, Matthew A.
Waychunas, Glenn A.
Fung, Inez Y.
MetadataShow full item record
Heightened biological activity was observed in February 1996 in the high-nutrient low-chlorophyll (HNLC) subarctic North Pacific Ocean, a region that is thought to be iron-limited. Here we provide evidence supporting the hypothesis that Ocean Station Papa (OSP) in the subarctic Pacific received a lateral supply of particulate iron from the continental margin off the Aleutian Islands in the winter, coincident with the observed biological bloom. Synchrotron X-ray analysis was used to describe the physical form, chemistry, and depth distributions of iron in size fractionated particulate matter samples. The analysis reveals that discrete micron-sized iron-rich hot spots are ubiquitous in the upper 200 m at OSP, more than 900 km from the closest coast. The specifics of the chemistry and depth profiles of the Fe hot spots trace them to the continental margins. We thus hypothesize that iron hot spots are a marker for the delivery of iron from the continental margin. We confirm the delivery of continental margin iron to the open ocean using an ocean general circulation model with an iron-like tracer source at the continental margin. We suggest that iron from the continental margin stimulated a wintertime phytoplankton bloom, partially relieving the HNLC condition.
Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 20 (2006): GB1006, doi:10.1029/2005GB002557.
Showing items related by title, author, creator and subject.
Lam, Phoebe J.; Bishop, James K. B. (American Geophysical Union, 2008-04-09)Here we show that labile particulate iron and manganese concentrations in the upper 500 m of the Western Subarctic Pacific, an iron-limited High Nutrient Low Chlorophyll (HNLC) region, have prominent subsurface maxima ...
Evidence from diatom-bound nitrogen isotopes for subarctic Pacific stratification during the last ice age and a link to North Pacific denitrification changes Brunelle, Brigitte G.; Sigman, Daniel M.; Cook, Mea S.; Keigwin, Lloyd D.; Haug, Gerald H.; Plessen, Birgit; Schettler, Georg; Jaccard, Samuel L. (American Geophysical Union, 2007-03-02)In a piston core from the central Bering Sea, diatom microfossil-bound N isotopes and the concentrations of opal, biogenic barium, calcium carbonate, and organic N are measured over the last glacial/interglacial cycle. ...
Pelagic diatom fluxes I : size fractioned time-series results from subarctic Pacific Station Papa during 1982-1983 Takahashi, Kozo; Povio, Danielle N.; Billings, John D.; Manganini, Steven J. (Woods Hole Oceanographic Institution, 1985-12)A time series vertical flux assessment of pelagic diatoms was conducted during September, 1982 through September, 1983 at subarctic Pacific Station PAPA (50°N, 145°W; water depth 4200 m) using PARFLUX sediment traps ...