Data Post Processing

Files of products that are based on retrievals (LWP, IWV, profiles) can be generated by combining brightness temperature files, meteorological sensor files and corresponding retrieval files. The frequencies specified in a retrieval file (see section 6 of the operating manual) must match the frequency list in the BT (Brightness Temperature) file. 
Example: An LWP retrieval requires BT information at 23.8 and 31.4 GHz and input from a temperature sensor and humidity sensor. A RPG-HATPRO radiometer stores this information in a brightness temperature file .BRT and .MET file. The calculation of the LWP data is performed in the Transform Brightness Temperature Data to Atmospheric Data. 
Example: The file 04102001.MET (select the filename from the list) is combined with the BT file 04102001.BRT (click on the filename in the list), both recorded at the same time and date, by applying the retrieval information of the LWP_QR_CAMB_V1.RET file. Generate LWP File performs a consistency check (frequency matching, additional sensor matching) and generates a new .LWP file. 
When a humidity profile MyFile.HPC is created, the software automatically looks for a matching relative humidity profile retrieval (RHP_...RET, installed in the …\Retrievals\HProfile sub-directory) in order to also create relative humidity profiles and append these to the absolute humidity profile chart. If such a retrieval is not found, the post processor looks for a MyFile.COM.TPC file (in the same data directory) containing a composite temperature profile chart (see section 5.16.3 of the operating manual). If this file is found, relative humidity profiles are calculated by combining the absolute humidity profiles (calculated from the MyFile.BRT brightness temperatures) and the temperature profiles in MyFile.COM.TPC. The relative humidity profiles are then appended to the absolute humidity profile information in MyFile.HPC. If MyFile.COM.TPC is not found, the software looks for a MyFile.TPC located in the same directory as MyFile.HPC and uses the temperature profiles of this file to create the relative humidity information. Only if neither MyFile.COM.TPC nor MyFile.TPC is found, the MyFile.HPC exclusively contains absolute humidity profiles.
The quality checking and flagging system is fully implemented in the post-processor. As in an MDF file which specifies the quality checking of level 2 data for a measurement, the same checking can be applied for post processing. Set the flags inside the Level 2 Data Quality box for this.
Even filter shifts can be applied to oxygen line BT data channels for post-processing. Enter channel filter shifts in the O2 Line Filter Shifts box if this is desired.