Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean

Abstract

[1] We investigate the functioning of the ocean's biological pump by analyzing the vertical transfer efficiency of particulate organic carbon (POC). Data evaluated include globally distributed time series of sediment trap POC flux, and remotely sensed estimates of net primary production (NPP) and sea surface temperature (SST). Mathematical techniques are developed to compare these temporally discordant time series using NPP and POC flux climatologies. The seasonal variation of NPP is mapped and shows regional-and basin-scale biogeographic patterns reflecting solar, climatic, and oceanographic controls. Patterns of flux are similar, with more high-frequency variability and a subtropical-subpolar pattern of maximum flux delayed by about 5 days per degree latitude increase, coherent across multiple sediment trap time series. Seasonal production-to-flux analyses indicate during intervals of bloom production, the sinking fraction of NPP is typically half that of other seasons. This globally synchronous pattern may result from seasonally varying biodegradability or multiseasonal retention of POC. The relationship between NPP variability and flux variability reverses with latitude, and may reflect dominance by the large-amplitude seasonal NPP signal at higher latitudes. We construct algorithms describing labile and refractory flux components as a function of remotely sensed NPP rates, NPP variability, and SST, which predict POC flux with accuracies greater than equations typically employed by global climate models. Globally mapped predictions of POC export, flux to depth, and sedimentation are supplied. Results indicate improved ocean carbon cycle forecasts may be obtained by combining satellite-based observations and more mechanistic representations taking into account factors such as mineral ballasting and ecosystem structure.Citation: Lutz, M. J., K. Caldeira, R. B. Dunbar, and M. J. Behrenfeld (2007), Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean,

Major impacts of climate change on deep-sea benthic ecosystems

“…html); (2) calculated the current seafloor pH from total inorganic CO 2 , total alkalinity, temperature, salinity, and pressure using the program CO2SYS (data on seafloor carbon content and the program CO2SYS were available from the Global Ocean Data Analysis Project at http:// cdiac.ornl.gov/oceans/; data on temperature, salinity and pressure were from the annual climatological mean from the World Ocean Atlas 2013); and (3) estimated POC flux to the global seafloor by first gathering data (from the portal www.science.oregonstate.edu/ocean.productivity) for global climatological monthly mean SeaWiFS (1998SeaWiFS ( -2007 and MODIS (from 2008-2010) Level-3 chlorophyll-a concentration and Level-4 VGPM ocean primary productivity (Behrenfield and Falkowski, 1997). The export POC flux at the seafloor was then calculated using an equation from Lutz et al (2007) based on the mean and seasonality (standard deviation/mean) of primary production, as well as the mean export depth below the euphotic zone over a 12-year period. The euphotic zone was calculated from the mean surface chlorophyll concentrations using the Case I model of Morel and Berthon (1989), while the export depth was calculated by subtracting the euphotic zone depth from the water depth.…”

Controls on mesopelagic particle fluxes in the Sub-Antarctic and Polar Frontal Zones in the Southern Ocean south of Australia in summer—Perspectives from free-drifting sediment traps

“…Globally distributed deep ocean sediment trap programs have revealed some of the factors that correlate with high POC flux, including the presence of ballast minerals (primarily autochthonous biogenic carbonates and silica, and secondarily allochthonous lithogenic particles) and the occurrence of strong seasonality (Lampitt and Antia, 1997;Armstrong et al, 2002;Francois et al, 2002;Klaas and Archer, 2002;Lutz et al, 2002Lutz et al, , 2007. However the importance of minerals is less clear at mesopelagic depths, where POC dominates particle contents to a much greater degree, particle size, and porosity are strong influences on sinking rates (Alldredge and Gotschalk, 1988;Alldredge, 1998;Passow, 2004;Stemmann et al, 2004;De La Rocha and Passow, 2007), and where the vast majority of flux attenuation occurs (Martin et al, 1987;Buesseler et al, 2007a).…”

Does energy availability predict gastropod reproductive strategies?

“…B 281: 20140400 ([10], p. 25). However, more recent studies of carbon flux to the seafloor suggest that the pattern is complex and does not follow systematic latitudinal patterns [27]. Nonetheless, regions of high latitudes often experience elevated carbon fluxes to the seafloor [27,35,36].…”

“…For each family, we quantified the median and standard deviation of carbon flux and temperature over their known latitudinal and depth ranges. To obtain the energy values, each family's biogeographic range was overlaid upon the Lutz et al's [27] model or NODC data. Depth and latitudinal range were pulled from Malacolog for the western Atlantic Ocean to estimate the biogeographic range of family.…”