This project sets out to develop improved particle flux
collectors and use these to answer key science questions associated
with C fluxes and exchange via sinking particles at the Bermuda
Atlantic Time-series Study (BATS) site. Currently at BATS,
we can’t balance surface ocean C budgets, annual new
production estimates, or link production and community structure
to predict particle export, and regularly fail to capture
episodic flux events. At the same time, we are trying to answer
these questions using an imperfect tool, the drifting sediment
trap, a device that has served us well but has not changed
significantly since the early 1980s.
This program is both innovative and ambitious, with the development
and engineering of new tools and its emphasis on the collection
of multi-annual time-series data, while being realistic in
starting from proven technology. We start by building upon
our recent success with the neutrally buoyant sediment trap
(NBST), but recognize that continuous flux collection and
swimmer free samples are needed, as envisioned for our new
design- the Twilight Zone EXplorer (TZEX).
A selection of PI sampling protocols and preliminary shared data are posted here.
TZEX NBST Sampling Protocol
AE0809 Sept. 2009 Cruise Summary Data and Event/CTD Logs
WHOI 11/29/09 Image of the Day- Sunset on the RV Atlantic Explorer.
Ocean color and altimeter data sets for TZEX study region (D. Siegel/E. Fields)
Dehairs, F., A. de Brauwere, M. Elskens, U. Bathmann, S. Becquevort, S. Blain, P. Boyd, K. Buesseler, E. Buitenhaus, M. Gehlen, G. Herndl, C. Klass, R. Lampitt, D. Lefevre, U. Passow, H. Plous, F. Primeau, L. Stemmann and T. Trull (2008). Controls on Organic Carbon Export and Twilight Zone Remineralization: An Overview of the EUROCEANS Workshop . Oceanography, 21(3): 92-95.
Dehairs, F., A. de Brauwere and M. Elskens (2008). Organic Carbon in the Ocean's Twilight Zone. EOS, Transactions American Geophysical Union, 89 (38): doi:10.1029/2008EO380004.
pump and processes regulating the flux of particles in
the ocean. Carbon dioxide fixed during photosynthesis
by phytoplankton in the upper ocean can be transferred
below the surface mixed layer via three major processes:
i) passive sinking of particles, ii) physical mixing of
particulate and dissolved organic matter (DOM), and iii)
active transport by zooplankton vertical migration. The
sinking flux includes senescent phytoplankton, zooplankton
fecal pellets, molts and mucous feeding-webs (e.g., larvacean
houses) and aggregates of these materials. The sinking
particle flux decreases with depth as aggregates are fragmented
into smaller, non-sinking particles, decomposed by bacteria,
and consumed and respired by zooplankton. This remineralization
returns carbon and nutrients to dissolved forms. The structure
of the planktonic community affects the composition and
the sinking rates of particles. Particle size, form, density,
and the content of biogenic minerals affect sinking and
Here's a link to our NSF Carbon and Water proposal entitled "Carbon Flux through the Twilight Zone- New Tools to Measure Change". Note that funding was cut significantly,
so the project is now a 4 (vs. 5) year effort and the "Stage
4" one week process cruises have been cut.
The Principal Investigators
Hole Oceanographic Institution
O. Buesseler (firstname.lastname@example.org)
H. Lamborg (email@example.com)
R. Valdes (firstname.lastname@example.org)
Institute of Ocean Sciences
Michael W. Lomas (email@example.com)
of California, Santa Barbara
David A. Siegel (firstname.lastname@example.org)
Institute of Marine Science
Deborah K. Steinberg (email@example.com)
The Study Site
Bermuda Atlantic Time-series Study
The Funding Programs
and Water in the Earth System
Please submit all information/corrections/improvements to
the site to Mary Zawoysky at firstname.lastname@example.org.
Updated: November 30, 2009