How to use obs2mesonh ?

obs2mesonh allows to replace observations on a Meso-NH grid. The output file has diachronic FM format, it can be used as input for diaprog to plot observations in the same background as MesoNH fields.
The input file is an ASCII one which contains the values of one type of observation : one per line, all lines have the same format (lon-lat-alt-value or lat-lon-alt-value). You need a diachronic FM file whose grids will be used to replace observation values.
obs2mesonh is an interactive tool. All the directives you enter on the keyboard are registered in the file dirobs2mnh. You can use it as input for the next call of the tool after being renamed.
file_diachronic_with_zs 	# initialize MesoNH spatial and temporal grids
0/1/2/3               	        # verbosity level
file_output           	        # name of the output file (FM)
LL/ll/DLL/Dll/LLa/lla/DLLa      # format of the obs file :  
					LL=   n lines Lon,Lat,val
                                	ll=   n lines lat,lon,val
 					DLL=  date (YYYYMMDDHHMISS) then n lines Lon,Lat,val
					Dll=  date (YYYYMMDDHHMISS) then n lines lat,lon,val
					LLa=  n lines Lon,Lat,alt(m),val
 					lla=  n lines lat,lon,alt(m),val
 					DLLa= date (YYYYMMDDHHMISS) then n lines Lon,Lat,alt(m),val
 					Dlla= date (YYYYMMDDHHMISS) then n lines lat,lon,alt(m),val
file_obs1                       # name of the obs file (undefined value = 999.0)
name_new_field1                 # name of the obs field in the output file
unit_new_field1                 # unit of the field
1D/2D/3D                        # profil of the obs field

END                             # closing of output diachronic file

The wind components are considered zonal and meridian in tne observation and are transformed to wind components in the Meso-NH grid. You have to name this variables Uxx Vxx and Wxx to plot them correctly with diaprog (vector, streamlines).

TANGUY Gaelle 2009-09-23