DataSheet1_Deep ocean particle flux in the Northeast Atlantic over the past 30 years: carbon sequestration is controlled by ecosystem structure in the upper ocean.pdf

• Main Authors: R. S. Lampitt, N. Briggs, B. B. Cael, B. Espinola, P. Hélaouët, S. A. Henson, F. Norrbin, C. A. Pebody, D. Smeed
• Format: Dataset
• Language: unknown
• Published: 2023
• Subjects: Solid Earth Sciences; Climate Science; Atmospheric Sciences not elsewhere classified; Exploration Geochemistry; Inorganic Geochemistry; Isotope Geochemistry; Organic Geochemistry; Geochemistry not elsewhere classified; Igneous and Metamorphic Petrology; Ore Deposit Petrology; Palaeontology (incl. Palynology); Structural Geology; Tectonics; Volcanology; Geology not elsewhere classified; Seismology and Seismic Exploration; Glaciology; Hydrogeology; Natural Hazards; Quaternary Environments; Earth Sciences not elsewhere classified; Evolutionary Impacts of Climate Change; carbon flux; Northeast Atlantic; sequestration; Rhizaria; Radiolaria; Foraminifera; biological carbon pump
• Online Access: https://doi.org/10.3389/feart.2023.1176196.s001; https://figshare.com/articles/dataset/DataSheet1_Deep_ocean_particle_flux_in_the_Northeast_Atlantic_over_the_past_30_years_carbon_sequestration_is_controlled_by_ecosystem_structure_in_the_upper_ocean_pdf/24313207

The time series of downward particle flux at 3000 m at the Porcupine Abyssal Plain Sustained Observatory (PAP-SO) in the Northeast Atlantic is presented for the period 1989 to 2018. This flux can be considered to be sequestered for more than 100 years. Measured levels of organic carbon sequestration (average 1.88 gm −2 y −1 ) are higher on average at this location than at the six other time series locations in the Atlantic. Interannual variability is also greater than at the other locations (organic carbon flux coefficient of variation = 73%). We find that previously hypothesised drivers of 3,000 m flux, such as net primary production (NPP) and previous-winter mixing are not good predictors of this sequestration flux. In contrast, the composition of the upper ocean biological community, specifically the protozoan Rhizaria (including the Foraminifera and Radiolaria) exhibit a close relationship to sequestration flux. These species become particularly abundant following enhanced upper ocean temperatures in June leading to pulses of this material reaching 3,000 m depth in the late summer. In some years, the organic carbon flux pulses following Rhizaria blooms were responsible for substantial increases in carbon sequestration and we propose that the Rhizaria are one of the major vehicles by which material is transported over a very large depth range (3,000 m) and hence sequestered for climatically relevant time periods. We propose that they sink fast and are degraded little during their transport to depth. In terms of atmospheric CO 2 uptake by the oceans, the Radiolaria and Phaeodaria are likely to have the greatest influence. Foraminifera will also exert an influence in spite of the fact that the generation of their calcite tests enhances upper ocean CO 2 concentration and hence reduces uptake from the atmosphere.