Runs with large scale forcing and nudging

Using nudging in a PALM simulation requires to provide nudging and large scale forcing 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 NUDGING_DATA and LSF_DATA respectively. In addition, the PALM configuration file .mrun.config has to be extended for the following two lines

...
#----------------------------------------------------------------------------
# List of input-files
#----------------------------------------------------------------------------
...
NUDGING_DATA             in:locopt     d3#:d3f  $base_data/$fname/INPUT    _nudge
LSF_DATA                 in:locopt     d3#:d3f  $base_data/$fname/INPUT    _lsf
...

With the following parameter file nudge_CBL_p3d a simulation with nudging can be performed. The nudging and large scale forcing data originate from a ​COSMO simulation of the 5th May, 2013, 9-15UTC. During this time a convective boundary layer with shallow cumulus clouds form.

 &inipar nx = 191, ny = 191, nz = 64,
         dx = 50.0, dy = 50.0, dz = 50.0,

         fft_method = 'fftw',

         humidity = .T., cloud_physics= .T.,

         nudging = .T.,

         large_scale_forcing = .T.,

         momentum_advec = 'ws-scheme',
         scalar_advec   = 'ws-scheme',

         initializing_actions = 'set_constant_profiles',

         bc_uv_b = 'dirichlet',
	 bc_pt_b = 'neumann',
	 bc_q_b  = 'neumann',

         phi = 50.92,

         pt_reference = 290.0,
         reference_state = 'single_value', 

         prandtl_layer = .T.,
         use_surface_fluxes = .T., 
         roughness_length = 0.01,

         rayleigh_damping_factor = 0.05,
         rayleigh_damping_height = 2700.0,
         scalar_rayleigh_damping = .T., /


 &d3par  end_time = 21600.0, 

         termination_time_needed = 300.0,

         npex = 64,
         npey = 1, 

         create_disturbances = .T.,

         netcdf_data_format = 2,

         dt_run_control = 30.0,
         dt_dots        = 30.0,

         dt_dopr = 1800.0,
         averaging_interval_pr = 1800.0, 
         dt_averaging_input_pr = 30.0,

         data_output_pr = '#u','#v','w','#pt','ug','vg',
                          '#lpt','#q','#qv','ql',
                          'e','e*','p','#km','#kh','#l',
                          'w"u"','w*u*','wu', 'w"v"','w*v*','wv',
                          'w"pt"', 'w*pt*', 'wpt', 
                          'w"vpt"', 'w*vpt*', 'wvpt', 
                          'w"q"', 'w*q*', 'wq', 
                          'w"qv"', 'w*qv*', 'wqv', 
                          'w*e*', 'u*2', 'v*2', 'w*2', 'pt*2', 'q*2',
                          'w*3', 'Sw', 'w*2pt*', 'w*pt*2',
                          'w*u*u*:dz','w*p*:dz', 'w"e:dz', 'hyp',

         data_output = 'u', 'v', 'w', 'pt', 'lpt', 'p', 'q', 'ql'
                       'u_xy', 'v_xy', 'w_xy', 'pt_xy', 'lpt_xy',
                       'p_xy', 'q_xy', 'ql_xy', 
                       'u_xz', 'v_xz', 'w_xz', 'pt_xz', 'lpt_xz',
                       'p_xz', 'q_xz', 'ql_xz', 
                       'shf*_xy', 'qsws*_xy', 'lwp*_xy',

         nz_do3d = 32, 

         dt_do3d        = 3600.0,
         dt_do2d_xy     = 3600.0,
         dt_do2d_xz     = 3600.0,
         dt_data_output = 3600.0,

         do2d_at_begin = .T., !->check perturbations

         section_xy = 2, 4, 10, 15, 20, 25,  
         section_xz = 96,

         data_output_2d_on_each_pe = .T.,  /

The external files nudge_CBL_nudge​ nudge_CBL_lsf​ 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).