VERtical Transport In the Global Ocean VERTIGO VERTIGO project web site What controls the efficiency of particle transport between the surface and deep ocean? Geochemistry (particle characteristics), Biology (euphotic zone and mesopelagic bacteria/plankton) Physics (particle source region) Cruises- Jan & June Hawaii HOT station ALOHA w/RV Kilo Moana July Station “K2” 47N 160E with RV Revelle

VERTIGO PI’s & Institution Ken Buesseler, Woods Hole Oceanographic Jim Bishop, Lawrence Berkeley National Phil Boyd, National Institute of Water and Atmospheric Res., NZ Karen Casciotti, Woods Hole Oceanographic Carl Lamborg, Woods Hole Oceanographic Institution Dave Siegel, University of California, Santa Barbara Mary Silver, University of California, Santa Cruz Debbie Steinberg, Virginia Institute of Marine Tom Trull, University of Tasmania, Australia Jim Valdes, Woods Hole Oceanographic Institution Ben Van Mooy, Woods Hole Oceanographic Frank Dehairs, University of Brussels, Belgium Collaborators Claudia Benitez-Nelson, University of South Carolina Bob Bidigare, University of Hawaii M. Sarin, Physical Research Laboratory, India Sei-ichi Saito, Hokkaido Univ., Japan Nianghi “George” Jiao, Xiamen Univ., China Toru Kobari, Kagoshima Univ., Japan

NBST – Neutrally Buoyant Sediment Trap Free vehicle Active buoyancy control <1 day to multi day mission Return to surface closed GPS & flasher

VERTIGO traps 10 in water! 300, 500m both HgCl 2 poisons & formalin (& blanks); 2 deployments “Splitter” wet split at sea with clean methods Analyses include- mass, C, N, P, PIC, bSi ICPMS- Fe, Ca, Al, Mn, Ti……. 234 Th, 210 Pb, 210 Po Chlorophyll pigments stable 13 C & 15 N DNA Microscope- ID, pellets, stains Frozen- organic biomarkers? Swimmer removal- screens & picking Separate experiments- “gel” traps Aging expt.

VERTIGO Site Surveys- sensors & geochemistry/biology

What a trap samples… Origins Collections Siegel et al. 250m surface trap

NBST CLAP Subtle differences between traps NBST remineralization “b” >drifting CLAP trap

- natural variability in flux vs. depth is common in all flux data - but less difference in relative compositions: element to element ratios see preferential remineralization of N over C - follows Redfield w/residual low C/N material intact

Iron shows less attenuation vs. depth than C C/Fe ratio decreases with depth NBST CLAP

Incubations of Poisoned Trap Material (and DOC from brine) Incubation shows scant evidence for systematic loss of particulate material, or in the case of C, appearance in the overlying brine (small impact on P) Short-deployment trap experiments are not likely subject to diagenetic artifacts. 1,3,5days

Incubations of Unpoisoned Large Particles from MULVFS Screens These unpoisoned samples do show evidence of loss of material from particle phase, esp. at the shallowest depth (compare to in situ changes vs. depth) 0,1,3,5 days 150m 300m 500m

Comparison of Unpoisoned Degradation Rate with Vertical Flux Attenuation to derive effective sinking rate ElementVertical “Half- Distance” Incubation “Half-Life” Sinking Rate Needed to Match P150 m3 days50 m d -1 Ca250 m2 days125 m d -1 Sr65 m2 days33 m d -1 Balarge1 daylarge

VERTIGO gear includes- Trull Boyd Bishop Steinberg/Silver Trull

Biological studies- zooplankton Steinberg et al.

- goal is to understand rates and controls of particle export and remineralization in the mesopelagic zone bacteria- rates & ID Van Mooy, Casciotti et al. phytoplankton- rates & ID Dehairs, Silver, Boyd et al.

Preliminary PIC data (est. from Ca) Changes in PIC:POC ratio impact strength of ocean C sink - ballast/PIC increases w/z - compare: ALOHA- Ca & coccolithophores vs. NW Pacific K2- bSi & diatoms

VERTIGO what’s next- - Summer 2005 VERTIGO cruise out of Japan - organize one day science workshop July 18- Yokohama 50% VERTIGO science presentations 50% Japanese time-series/K2/particle science - Japanese & Chinese scientists to join cruise (n=4) - July 21-Aug 28, RV Revelle, Yokohama to Honolulu - Special mesoplelagic/particle flux session Feb Ocean Sciences meeting, Honolulu Joint with Cindy Lee (MedFlux); Hiroaki Saito (DEEP) & Buesseler (VERTIGO) PI meeting 2.5 days- prior to Ocean Sciences mtg. - VERTIGO II?

VERTIGO PI’s & Institution Ken Buesseler, Woods Hole Oceanographic Jim Bishop, Lawrence Berkeley National Phil Boyd, National Institute of Water and Atmospheric Research Karen Casciotti, Woods Hole Oceanographic Carl Lamborg, Woods Hole Oceanographic Institution Dave Siegel, University of California, Santa Barbara Mary Silver, University of California, Santa Cruz Debbie Steinberg, Virginia Institute of Marine Tom Trull, University of Tasmania Jim Valdes, Woods Hole Oceanographic Institution Ben Van Mooy, Woods Hole Oceanographic Collaborators Claudia Benitez-Nelson, University of South Carolina Bob Bidigare, University of Hawaii Frank Dehairs, University of Brussels M. Sarin, Physical Research Laboratory S. Honjo & Japanese scientists? K2 site

Horizontal flow (hydrodynamics) Shallow sediment traps Preservation (solubilization in collection tubes) Swimmers - accuracy issues

VERTIGO Site Surveys- sensors & geochemistry/biology

An assessment of particulate organic carbon to thorium-234 ratios in the ocean and their impact on the application of 234Th as a POC flux proxy K. O. Buesseler, C. R. Benitez-Nelson, S. B. Moran, A. Burd, M. Charette, J. K. Cochran, L. Coppola, N. S. Fisher, S. W. Fowler, W. D. Gardner, L. D. Guo, O. Gustafsson, C. Lamborg, P. Masque, J. C. Miquel, U. Passow, P. H. Santschi, N. Savoye, G. Stewart, and T. Trull Submitted March 2005

Marine Particles “separate biogeochemistry from physical oceanography” Marine Particles “separate biogeochemistry from physical oceanography” How do we get from here? C uptake in surface ocean- SeaWiFS global primary production Behrenfeld & Falkowski, 1997 To here? C flux to seafloor - benthic O 2 demand Jahnke, 1996

Diatom assoc. flux high “b” Coccolithophorid assoc. POC flux Why can’t diatoms control upper ocean export on regional or seasonal basis, while CaCO 3 materials show stronger association with deep flux? Differences abound- in diatom types, sinking rates & bSi/C ratios

Carbon flux = 234 Th flux  [C/ 234 Th] sinking particles Empirical approach Highest in (diatom) blooms & coastal ocean Must use site and depth appropriate ratio Issues remain on how best to sample particles