| Summary: | This dataset contains the output of Lagrangian particle tracking experiments using 5-day mean velocity and hydrographicfields from the ORCA025-GJM189 ocean sea-ice model hindcast configured during theDrakkar project in which numerical particles are initialised along the northwardinflows across the Overturning in the Subpolar North Atlantic Program (OSNAP) Eastsection. Particles are advected using a bespoke version of TRACMASS v7.1 Lagrangianparticle tracking tool using the regular step-wise stationary advection scheme andan adapted implementation of the vertical turbulent mixing parameterisation createdby Paris et al. (2013) for the Connectivity Modelling System Lagrangian particletracking tool. This vertical turbulent mixing scheme only acts on particles foundwithin the surface mixed layer (as evaluated along particle trajectories) andrandomly reshuffles them according to a maximum vertical velocity of 10 cm/s -characteristic of vertical convective plumes. Note, particles cannot be artificiallysubducted across the base of the mixed layer into the ocean interior using this scheme. Particles are initialised on the first-available day of each month (based on thecentre of the model fields 5-day mean windows) between 1976 and 2008 (inclusive)before being advected within the Iceland and Irminger Basins until any one of threetermination conditions are met: 1) particles return southward across OSNAP East,2) particles flow northward across the Greenland-Scotland Ridge, or 3) particles reachthe maximum advection time of 7-years. The 7-year maximum advection time ensures >99.1%of all initialised particles meet one of conditions 1) or 2), hence only 0.9% of allparticles are terminated between OSNAP East and the Greenland-Scotland Ridge. The number of particles initialised in each model-grid cell scales with the totalnorthward transport through that cell, such that the maximum possible transportconveyed by any single particle is 2.5 mSv (mSv == 1E-3 Sv),enablingthe calculation of robust Lagrangian statistics. Particle ...
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