PLUME1.1: deposition of sediment from fluvial plume

An ANSI-standard Fortran 77 program solves the steady, two-dimensional advection-diffusion equation describing a turbid hypopycnal plume emanating from a river mouth. The model solves for the extent of the plume as a non-dimensioned inventory of sediment mass on an axial-lateral grid. The basis for the model is a derivation by Albertson for a two-dimensional momentum-driven submerged jet. Particle settling is based on the scavenging model of Syvitski. PLUME is robust but fast enough to handle the sedimentation beneath a river plume flowing into a coastal sea on a daily basis. Designed for speed, the model may be run with daily-changing river input characteristics (flow velocity, river mouth dimensions, sediment concentrations of up to ten grain sizes) for many (up to thousands of) years. PLUME1.1 works with input from long-term field observations or from climate-hydrologic simulations. The model provides for an improved geological simulator of land-sea interaction and the delivery of sediment onto continental margins. The model can be used to simulate flow into both open-coast and semi-enclosed basins. Open-coast plume simulations include the flood-dominated Eel River margin, Northern California, where a three-day flood event could supply more sediment than the previous seven years combined. A semi-enclosed basin example is from a fjord-basin from British Columbia, where model simulations agree well with sediment concentration observations.