RFM Output Files

26SEP17

Running the RFM will always create a file rfm.runlog (rfm.log for RFM v5.0 onwards) (plus any run_ID extension to the filename). This contains diagnostic information on the progress of the particular run of the RFM, eg listing section of the Driver Table being read, names of files which are about to be opened, warning messages.

Other output files depend on the Driver Table, specifically on the Flags enabled in the *FLG section of the driver table. The available output options can be limited by other flags, usually because the type of output is not meaningful with a particular type of calculation - see under individual output flags for details.

Spectral Files

The main purpose of the RFM is to generate spectral files, written either as ASCII (default) or Binary (BIN flag) files, in Single (default) or Double (DBL flag) precision.

A separate file is generated for each spectral range, label [s] (as defined in the *SPC section) and tangent height/viewing geometry [t] (as defined in the *TAN section).

Flag Description Units Filename
ABS Absorption (=1-transmission) Spectrum [none] abs_[s][t].asc
BBT Brightness Temperature Spectrum [K] bbt_[s][t].asc
COO Cooling Rate Spectrum (with FLX Flag) [K/day/cm-1] coo_[s][t].asc
OPT Optical Depth (=-ln(transmission)) Spectrum [none] opt_[s][t].asc
RAD Radiance Spectrum, or [nW/(cm2.st.cm-1)] rad_[s][t].asc
(with FLX flag) Radiance Flux Spectrum [W/(m2.cm-1)]
RJT Rayleigh-Jeans Temperature Spectrum [K] rjt_[s][t].asc
TRA Transmission Spectrum [none] tra_[s][t].asc

Diagnostic Files

Additional diagnostic information (ASCII files only) can be produced for the internal profile, ray-tracing and line-by-line calculations, with separate files generated for different line-of-sight angles [l] (as specified in the *ATM section if GRA flag selected), tangent height/viewing geometry [t] (as specified in the *TAN section) and spectral range [s] as specified in the *SPC section) respectively.
Flag Description Filename
PRF Atmospheric Profile prf_[l].asc
PTH Ray Path Diagnostics pth_[t].asc
WID Widemesh Diagnostics wid_[s].asc

Lookup Tables

The RFM can generate lookup tables of absorption coefficient tabulated as functions of pressure, temperature and wavenumber. One table is generated for each spectral range [s] (as defined in the *SPC section) and absorbing species [g] (defined in the *GAS section). These can be used as input files (LUT flag) as a faster alternative to line-by-line calculations.
Flag Description Units Filename
TAB Absorption Coefficient table [m2/kmol] tab_[s][g].asc

Changing Output Filenames

The RFM has default filename templates for each class of output file, as listed in the tables above, which will create the files in the user's directory. The actual filenames as they are opened are listed in the rfm.runlog file.

The simplest way to modify the output filename (eg to distinguish the output from similar runs) is to enter characters in response to the Run ID prompt.

For more radical changes, including redirecting to different directories, it is possible to alter the default templates by adding optional sections to the driver table. These optional section match the flag which creates the output. If multiple files are created, it is necessary for the template to contain a wildcard character '*' which will be expanded to provide a unique spectral_range/gas/tangent_height identifier. For example, if the user specifies output filenames for transmission files by adding a section to the Driver Table:

*TRA
      ./out/rfm_*.tra
Then, for tangent heights 20, 25 km and spectral ranges labelled 'a' and 'b', 4 files will be created in directory ./out/ with filenames:
	rfm_a20000.tra
	rfm_a25000.tra
	rfm_b20000.tra
	rfm_b25000.tra

Other Output Options

Flag Description Effect
BIN Write spectra and LUTs as Binary files rather than ASCII files Generates smaller files and faster I/O, but more difficult to read
DBL Write spectra as double precision Internal radiance/transmittance are stored as double precision but output by default is single precision. This option generates larger output files.
LUN Reuse Logical Unit Numbers for output files rather than maintain a separate open LUN for each Avoid exceeding limited number of available LUNs on some machines, at expense of slightly slower write time (redundant in RFM v5.0)
NEW Open output files with STATUS='NEW' in FORTRAN OPEN statement rather than STATUS='UNKNOWN' Avoids overwriting any existing files of the same name (any attempt will result in a fatal error condition)