Project: Time Series Particle Flux Measurements in the Sargasso Sea

The Oceanic Flux Program (OFP) has continuously measured particle fluxes in the deep Sargasso Sea since 1978. The OFP is the longest running continuous time-series of its kind, and has produced a unique record of temporal variability in material transfer from the surface to the deep ocean (the “biological pump") resulting from the interplay between physical, biological and chemical processes. The OFP deploys a subsurface mooring anchored in 4500m of water with three McLane Research Parflux Mark 8 sediment traps located at 500m, 1500m and 3200m depths. These traps continuously collect the sinking particle flux at an approximate 2 week sampling resolution.

The most recent project awards and abstracts are listed below.  A detailed history of funding with summary of all project awards for OFP can be found below.

October 2024 through September 2027
NSF Award OCE-2421112 Abstract:

This award provides an additional three years of support for the Oceanic Flux Program (OFP). The OFP was established in 1978 to measure the export flux of particles from the surface to the deep ocean in the deep Sargasso Sea near Bermuda. The OFP is the longest and most continuous particle flux time-series of its kind. Through collaboration with nearby upper ocean time-series programs, facilities, and other Bermuda-based sampling programs, OFP will continue to be a valuable resource for the oceanographic community in the effort to answer questions about the intricate relationship between deep ocean particle flux and climate, as well as biological, physical, and chemical oceanographic processes. Looking to the future, OFP will use increasingly advanced instrumentation and state-of-the-art analytical tools to investigate the nature and patterns of the material that sinks from the surface to deep ocean and the mechanisms that drive that process. The OFP provides education and training for students from high school to Ph.D. levels and supports early career researchers. OFP data and samples are broadly available to other researchers across the scientific disciplines.

Two overarching goals drive core activities funded under the OFP grant. The first is to extend the time-series by collecting new samples of the highest quality, while ensuring they have a comprehensive oceanographic context. The second is to elucidate the processes that drive oceanic particle flux through comparative studies of flux magnitude and composition with concurrent observations of external forcing (e.g., synoptic scale meteorology, climate patterns), surface water physics and biology (e.g., mesoscale features, blooms), and interior processes (e.g., biological particle aggregation/disaggregation, elemental scavenging, authigenic mineralization). The specific grant objectives are: (1) to provide for continuity of the particle flux measurements at 500, 1500 and 3200 m depths and continue to refine the quality of the time-series record and expand its oceanographic context, (2) to update/calibrate OFP sample processing and analytical methods to enhance the time-series data record, and to curate the time-series sample archives for future study, (3) to promote collaborative research to maximize interdisciplinary information obtained from the samples, (4) to conduct focused studies to identify deep flux temporal trends and their coherence with upper ocean forcing, to elucidate causal flux generation processes, and to develop proxies for climate studies,
(5) to provide education and training opportunities. A particular focus of this funding cycle will be to analyze the extensive OFP digital image archive with an automated (and/or semi-automated) approach, including classical methodologies and Deep Learning (DL) based tools for image classification, segmentation and archive, and a Graphical User Interface (GUI). The development of these new tools for identification, quantification, and characterization of the flux material will better exploit the image archive's potential, as fuller characterization of biological components will contribute new information on the ecosystem dynamics and responses to environmental forcing that drive flux generation.
 

October 2023 through September 2025
NSF Award OCE-2414704 Abstract:

This award provides an additional three years of support for the Oceanic Flux Program (OFP). This program was first established in 1978 to measure the export flux of particles from the surface to the deep ocean in the deep Sargasso Sea and represents the longest and most continuous particle flux time-series of its kind. This program and the time-series record will continue to help the oceanographic community to answer questions about the relationship between deep ocean particle flux and climate and biological, physical, and chemical oceanographic processes. In the past, the OFP has provided evidence for coupling between the upper and deep ocean processes linked to seasonal, episodic (e.g., physical and meteorological forcing) and climate patterns. Looking to the future, this program will utilize increasingly advanced instrumentation and analytical tools to address questions about the material that sinks from the surface to deep ocean and its controls. The OFP provides education and training for students from the high school to Ph.D. level and supports early career researchers.

The OFP time-series represents a 43-year, nearly continuous record focused on particle fluxes in the deep ocean. With increasingly more data available from the lengthening record, investigators can put observed biogeochemical patterns into perspective to understand the interplay between climate and ocean functioning. The availability of data from complementary nearby Hydrostation S, the Bermuda Atlantic Time-Series (BATS), the Bermuda Testbed Mooring (1994-2007), the Tudor Hill atmospheric tower and other Bermuda sampling programs provide additional opportunities to study upper ocean physics and biogeochemistry coupled with deep ocean biogeochemical processes. The OFP record is becoming long enough to study deep flux linkages with gyre circulation and advective processes. The OFP's archive is an unparalleled resource for retrospective studies of temporal trends and the biogeochemical consequences of a changing ocean, including future impacts of ocean acidification. As the OFP heads into the future, increasingly sophisticated OFP mooring instrumentation (ADCP current profiling and backscatter; MicroCAT temperature, salinity, and oxygen measurements) and advances in digital imaging and analytical tools (both chemical and genomic) to probe the recovered flux materials continue to reveal novel, fundamental information about the oceanic particle flux and its controls