Figure 5. Background fluxes of particulate organic carbon, biogenic and lithogenic silica versus depth.
Plots represent fluxes of POC (grey), bSi (green) and lSi (brown) calculated using the background biogeochemical concentrations and a conservative sinking velocity of 18 m d-1. The filled area represents the upper bound fluxes up to values estimated using a sinking velocity of 36 m d-1. The values are cruise-wide averages calculated for five depth layers (50–65, 95, 195, 300–350 and 500 m). Error bars are calculated as standard deviations averaged within each depth layer and thus are reflective of the dataset variability rather than the propagated uncertainty of each datapoint. Note that we have one observation for all biogeochemical components at 195 m and one for bSi and lSi at 20 m. Hence, these depths are not well represented by our dataset.