## EcoTiM

### What is it?

**EcoTiM** is a complex ecosystem model which dynamically simulates the cycling
of organic carbon, nitrogen, phosphate silicate and oxygen within
the back barrier system of the East Frisian island Spiekeroog.

The model has the capability to resolve the seasonal cycles as well as tidal
processes. It consists of several interlinked modules describing the
pelagic and benthic foodweb, the microbial loop including the
distribution of detritus.

The description of the biochemical and ecological processes bases mainly on ERSEM.

### How does it work?

The model is implemented with a semi Euler-Lagrangian scheme. Lagrangian water bodies -called voxels- move along a
surface velocity field. The whole ecosystem model is calculated in
each voxel. The
consideration of finite water bodies allows the mass conserving
coupling to the benthic system.

The water bodies interact with the benthic system
below their actual position. The area of interaction with the
benthic system depends on the actual water level. The benthic system is represented by
different sediment areas - called boxes- defined according to topography and porosity.

### How is it forced?

The boundary conditions are
given by the Continental Coastal Application of North Sea application
of ERSEM called COCOA. The physical forcing is given by
physical forcing is given by

- surface velocity field
- time series for temperature
- time series for irradiance
- time series for suspended matter
- surface velocity field
- time series for tide level
- flood gate input
- precipitation