NEMO-PISCES DSi concentration in the Labrador Sea

This focus on the Labrador Sea is part of the global NEMO-PISCES model used in the publication "Contribution of physical processes to dissolved silica variability in the Labrador Sea between 1980-2015" by Dale et al., to be submitted in Geophysical Research Letters. The variables provided are as follows: dissolved silica (Grid_T), conservative temperature (Grid_T), absolute Salinity (Grid_T), mixed layer depth (Grid_T), specificity of the grid (mesh_mask), effective transport (Grid_U and Grid_V). The associated paper investigates the drivers of the decline in the pre-bloom Dissolved Silica (DSi) inventory observed in the upper layer (0-450 m) of the Labrador Sea between 1994-2007 and its InterAnnual Variability (IAV) over the 1980-2015 period. It assesses the relative contributions of the variability of deep winter convection (DWC) and inflow from the Arctic as DSi sources using an eddy-permitting biogeochemical ocean general circulation model. The IAV of the upper layer DSi inventory co-varies with both the Arctic inflow and DWC. The pre-bloom decline seems driven by the DWC and induced winter vertical mixing, while the Arctic inflow’s contribution is negligible. Our study suggests that the inventory decline is part of its natural decadal variability influenced by two major climate modes, the North Atlantic and the Arctic Oscillations. The former appears to be the main control. Reference (article) : Dale, A., Alekseenko, E., Ethé, C., Bénard, G. Wallace, D.W.R., Gehlen, M. Contribution of physical processes to dissolved silica variability in the Labrador Sea between 1980-2015. To be submitted to Geophysical Research Letters.