# 2.6. Resource forcing¶

## 2.6.1. Osmose <= 4.0.0¶

In Osmose versions <= 4.0.0, there were several ways to read the resource forcing files, depending on the value of the ltl.java.classname parameter.

### 2.6.1.1. ECO3M¶

If the class name is set equal to fr.ird.osmose.ltl.LTLForcingECO3M or fr.ird.osmose.ltl.LTLFastForcingECO3M, data values were read as follows.

 ltl.nstep Number of total time steps in the LTL files plankton.conversion2tons.plk# Conversion factor in tons ltl.netcdf.var.plankton.plk# Names of the Netcdf resource names ltl.netcdf.file.t# Names of the NetCDF files to read. ltl.netcdf.var.zlevel Name of the 3D depth variable grid.stride# Number of input cells that will be aggregated in an Osmose cell. ltl.integration.depth Maximum depth where to perform vertical integration

### 2.6.1.2. BFM¶

If the class name is set equal to fr.ird.osmose.ltl.LTLForcingBFM or fr.ird.osmose.ltl.LTLFastForcingBFM, data values were read as follows.

 ltl.nstep Number of time steps within a file. plankton.conversion2tons.plk# Conversion factor in tons ltl.netcdf.var.plankton.plk# Names of the Netcdf resource names ltl.netcdf.file.t# Names of the NetCDF files to read. ltl.netcdf.dim.ntime Number of time steps within a file grid.netcdf.file Name of the bathymetry file ltl.netcdf.var.zlevel Name of the 1D depth variable ltl.netcdf.var.bathy Name of the bathymetry variable ltl.integration.depth Maximum depth where to perform vertical integration

### 2.6.1.3. ROMS/PISCES¶

If the class name is set equal to fr.ird.osmose.ltl.LTLForcingRomsPisces or fr.ird.osmose.ltl.LTLFastForcingRomsPisces, data values were read as follows.

 ltl.nstep Number of time steps within a file. plankton.conversion2tons.plk# Conversion factor in tons ltl.netcdf.var.plankton.plk# Names of the Netcdf resource names ltl.netcdf.file.t# Names of the NetCDF files to read. ltl.netcdf.grid.file Name of the grid file ltl.netcdf.var.lon Name of the longitude variable ltl.netcdf.var.lat Name of the latitude variable ltl.netcdf.var.bathy Name of the bathymetry variable ltl.netcdf.var.csr Name of the CSR variable ltl.netcdf.var.hc Name of the Hc variable ltl.integration.depth Maximum depth where to perform vertical integration

### 2.6.1.4. Fast forcing¶

In the above configurations, Osmose processes the file to convert them into the right format. However, there is also the possibility to use a file already in the right format using the fr.ird.osmose.ltl.LTLFastForcing class.

 ltl.nstep Number of time steps within a file. ltl.netcdf.file Name of the resource NetCDF file plankton.biomass.total.plk# Total biomass within the domain. If not found, reads value from NetCDF plankton.multiplier.plk# Multiplier of input biomass (default 1, used to run sensitivity experiments).

The netcdf file must contain a 4d variable ltl_biomass, whose dimensions are (time, ltl, lat, lon)

Danger

The order along the ltl dimension must be consistent with the order of definition of the plankton parameters.

Danger

With the fast forcing, the plankton.conversion2tons.plk# parameter is not used since data must be provided in tons!

## 2.6.2. Osmose 4.1.0 - 4.2.0¶

In versions 4.1.0 and 4.2.0, only the FastForcing method has been kept. However, it has been slightly improved. Now the model can take one NetCDF file per resource variable, and the variable in the NetCDF must match the plankton.name.plk# parameter. In this way, there is no more dependency on the order.

 plankton.biomass.total.plk# Total biomass within the domain. If not found, reads value from NetCDF ltl.nstep Number of time steps within a file. ltl.netcdf.file.plk# Name of the resource NetCDF file (one for each resource) plankton.multiplier.plk# Multiplier of input biomass (default 1, used to run sensitivity experiments).

Danger

Resource species for which plankton.biomass.total.plk# is used should be defined last, i.e. their index # should be greater than those of the other species.

Danger

The resource files must be provided in tons! **The plankton.conversion2tons.plk# parameter is not used.

## 2.6.3. Osmose >= 4.3.0¶

In the 4.3.0 version, the resource forcing remains similar to versions 4.1-4.2, with some changes in parameters.

 species.biomass.total.sp# Total biomass for the given ressource (will be distributed over the whole domain) species.file.sp# Regular expression defining the input files. Can be a file name. species.file.caching.sp# Resource caching method. Must be none, incremental or all (default).

If the species.biomass.total.sp# is not found, then the value will be read from the NetCDF file.

The species.file.sp# parameter can now take as an input regular expressions, which will allow to loop over all the files. The regular expressions must be defined in Java mode (see for instance XXX).

The species.file.caching.sp# defines how the input data will be read:

• In all mode, all the dataset is read at the first time step and stored into memory. Should be used for climatological forcings for instance.

• In incremental mode, each time a new time-step is read from file, it is stored in memory. Previous time-steps are kept in memory.

• In none mode, the data is read from file at each time-step. This mode is costly in term of runtime but light in memory since only one time-step is stored.

Note

In version 4.3.0, the resource forcing parameter also applies to background species.