The global ocean flux by particulate organic carbon: Areal distribution and magnitude

Journal Article · Fri Mar 01 04:00:00 EST 1996 · Global Biogeochemical Cycles

DOI:https://doi.org/10.1029/95GB03525· OSTI ID:244054

Jahnke, R A ^[1]

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1. Skidaway Institute of Oceanography, Savannah, GA (United States)

The magnitude and distribution of the particulate organic carbon (POC) rain rate to the seafloor in the Atlantic, Pacific and Indian Ocean basins between 61{degrees}N and 61{degrees}S has been estimated from benthic oxygen flux estimates (for water depths {ge} 1000 m). The calculation uses extensive data sets of sedimentary organic carbon and accumulation rate to extrapolate between individual benthic flux measurement sites using an empirically-derived correlation between the seafloor oxygen flux and these parameters. The POC flux through the 1000 m depth horizon was estimated from published correlations between sediment trap-determined fluxes and water depth. Total oxygen utilization in the deep ocean is estimated to be 1.2x10{sup 14} mol O{sub 2} yr{sup -1}, which agrees well with previous estimates and with deep water respiration rates. Based on the derived global ocean flux distribution, it is concluded that (1) dissolved organic carbon (DOC) inputs are not required to account for estimated deep water respiration rates; (2) the majority of the POC input to the deep ocean occurs within 30{degrees} of the equator; (3) the proportion of primary production that reaches the deep sea does not vary greatly with latitude; (4) gyre and continental margin regions contribute roughly equally to the deep POC flux with a relatively minor contribution from the equatorial divergence region; (5) of the estimated 7.2x10{sup 13} mol C yr{sup -1} of POC that sinks below the 1000 m depth horizon, 45% (3.3x10{sup 13} mol C yr{sup -1}) reaches the seafloor where it is oxidized; (6) when normalized to basin area, average deep flux rates in the Atlantic and Pacific are similar while highest rates are observed in the Indian Ocean; and (7) the results can be fully reconciled only if the benthic flux of DOC is significantly less than the benthic O{sub 2} flux. 51 refs., 5 figs., 3 tabs.

• DOE Contract Number: FG02-92ER61415
• OSTI ID: 244054
• Journal Information: Global Biogeochemical Cycles, Journal Name: Global Biogeochemical Cycles Journal Issue: 1 Vol. 10; ISSN GBCYEP; ISSN 0886-6236
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
54 ENVIRONMENTAL SCIENCES
58 GEOSCIENCES
ATLANTIC OCEAN
BUILDUP
CARBON
CARBON CYCLE
ENVIRONMENTAL TRANSPORT
INDIAN OCEAN
PACIFIC OCEAN
PARTICULATES
RAIN
SEA BED
SEDIMENTS
SPATIAL DISTRIBUTION