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Abstract Tropical cyclones erode and remobilize coastal sediments but their impact on the deep ocean remains unclear. Hurricane‐driven transport of carbonates and associated materials from reef carbonate platforms to the deep ocean has important implications for carbon storage, deep ecosystems and ocean chemistry as carbonate platform reef‐sourced aragonite and high‐Mg calcite (HMC) may dissolve and contribute to deep water total alkalinity. Here we describe two hurricane‐driven resuspension events where deep sediment plumes from the Bermuda Pedestal (NW Atlantic) were advected to deep waters surrounding the Oceanic Flux Program (OFP) mooring site, ∼75 km southeast of Bermuda. Hurricanes Fabian (Cat. 3, 2003) and Igor (Cat. 1, 2010) generated large near‐inertial waves propagating to >750 m depths, leading to widespread sediment resuspension from the Pedestal. Following Fabian, carbonate fluxes at the OFP site increased 15‐fold, 32‐fold, and 6‐fold at 500, 1,500 and 3,200 m, respectively, with the 1,500 m flux equivalent to the total annual carbonate flux. OFP traps similarly captured a large detrital carbonate plume following Igor; here, the plume was shallower and persisted longer. Microscopy, geochemistry, and mineralogy confirmed that both plumes consisted of fine‐grained shallow‐water detrital carbonates alongside other materials accumulated on the Pedestal including phosphorus, lithogenic, authigenic, and pollutant elements. Clay‐sized particles (<4 μm) in both plumes exhibited high contents of lithogenic and authigenic elements, and Zn, Cd, and V, facilitating their transport over long distances. Grain‐size, elemental, and lipid composition indicated that plumes intercepted at different depths originated from different source areas on the Pedestal.
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This content will become publicly available on June 1, 2026
The climatology of the deep particle flux in the oligotrophic western North Atlantic gyre, 1978–2022
The oceanic particle flux controls, in part, ocean biogeochemical cycles and long-term carbon sequestration. The Oceanic Flux Program (OFP), the longest running time series of its kind, has continuously measured the deep particle flux in the oligotrophic Sargasso Sea southeast of Bermuda since 1978. This paper describes the deep flux climatology at the OFP site over the 1978–2022 time period. Mass flux at 500 m, 1500 m and 3200 m depths has averaged 27.2, 34.8 and 36.8 mg m−2 d-1, respectively. Carbonates comprise ∼ 60 % of the flux, with lesser amounts of organic matter, opal and lithogenics. Flux magnitude and composition vary seasonally with large interannual variability, particularly in the winter/spring flux maximum. Flux frequency distributions are strongly skewed, especially at 500 m depth where flux magnitude and compositional variability are highest. Flux seasonality, skewness and compositional heterogeneity decrease markedly with depth. A significant component of the deep flux is sourced from large particle production in the deep water column (e.g. suspended material repackaging) rather than directly from the overlying export flux. Lithogenic flux increases five-fold between 500 m and 3200 m depths, underscoring the importance of deep lateral advection and lithogenic particle removal via particle cycling processes. Multidecadal averages in deep carbon fluxes are compared with concurrent monthly data on overlying net primary production (PP) and surface export flux (EF, measured by drifting traps at 150 m depth) at the nearby Bermuda Atlantic Time Series (BATS) site. Carbon fluxes are temporally coherent throughout the water column (within the sample resolution) and lag primary production by ∼ one month. Approximately 0.6 %, 0.5 % and 0.4 % of PP reaches the 500, 1500 and 3200 m depth horizons, respectively, with the highest depth penetration occurring during the Jan-Mar period of peak primary production. Annually, 7.6 % and 6.2 % of the EF reaches the1500 and 3200 m depth horizons, respectively, with the highest transfer efficiency (9.1 % and 7.4 %, respectively at 1500 and 3200 m depths) during the post-bloom (Apr-Jun) period. The OFP flux climatology summarized here provides an important baseline for assessing future consequences of a changing climate on ocean functioning in the oligotrophic North Atlantic gyre.
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- PAR ID:
- 10620800
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Progress in Oceanography
- Volume:
- 234
- Issue:
- C
- ISSN:
- 0079-6611
- Page Range / eLocation ID:
- 103433
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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