Numerical Lagrangian trajectory modeling is a natural method of investigating transport in a circulation system and understanding the physics on the wide range of length scales that are actually experienced by a drifter. A previously-developed tool, TRACMASS, written in Fortran, accomplishes this modeling with a clever algorithm that operates natively on the commonly used staggered Arakawa C grid. TracPy is a Python wrapper written to ease running batches of simulations. Some improvements in TracPy include updating to netCDF4-CLASSIC from netCDF3 for saving drifter trajectories, providing an iPython notebook as a usermanual for using the system, and adding unit tests for stable continued development.

Keywords:Lagrangian trackingnumerical driftersPython wrapper