=== Runs with large scale forcing and nudging ===

Using large scale forcing and nudging in a PALM simulation requires to provide large scale forcing and nudging data in external files. The file names should have the endings _nudge and _lsf respectively. They have to be placed in the INPUT directory on the host where the simulation will run. The layout of the data in the files is described in [../../iofiles#LSF_DATA LSF_DATA] and [../../iofiles#NUDGING_DATA NUDGING_DATA] respectively. In addition, the palmrun IO file [source:palm/trunk/SCRIPTS/.palm.iofiles .palm.iofiles] has to be extended for the following two lines
{{{
...
#----------------------------------------------------------------------------
# List of input-files
#----------------------------------------------------------------------------
...
NUDGING_DATA             inopt:tr   d3#:d3r  $base_data/$run_identifier/INPUT    _nudge
LSF_DATA                 inopt:tr   d3#:d3r  $base_data/$run_identifier/INPUT    _lsf
...
}}}

With the following parameter file [[attachment:lsf_CBL_p3d|lsf_CBL_p3d]] a simulation with large scale forcing and nudging can be performed. The large scale forcing and nudging data originate from a [http://cosmo-model.org/ COSMO] simulation of the 24th April, 2013, 9-15UTC. During this time a convective boundary layer develops. 
The external files [[attachment:lsf_CBL_lsf|lsf_CBL_lsf]] [[attachment:lsf_CBL_nudge|lsf_CBL_nudge]] are attached. The nudging time scale tau is 6 hours and the nudging is performed in the whole model domain (boundary layer and free atmosphere). For more information how to set large scale forcing and nudging see parameters [../../initialization_parameters#large_scale_forcing large_scale_forcing] and [../../initialization_parameters#nudging nudging]