ELCIRC is an unstructured-grid model designed for the effective simulation of 3D baroclinic circulation across river-to-ocean scales. It uses a finite-volume/finite-difference Eulerian-Lagrangian algorithm to solve the shallow water equations, written to realistically address a wide range of physical processes and of atmospheric, ocean and river forcings. The numerical algorithm is low-order, but volume conservative, stable and computationally efficient. It also naturally incorporates wetting and drying of tidal flats. While originally developed to meet specific modeling challenges for the Columbia River, ELCIRC has been extensively tested against standard ocean/coastal benchmarks, and is starting to be applied to estuaries and continental shelves around the world.
