.tab File | ||
RFM File Formats: Look-Up Table of Absorption Coefficient |
04JUN24 |
where | k | m2/kmole | Absorption cross-section |
ν | cm-1 | Wavenumber | |
p | hPa | Pressure | |
T | K | Temperature | |
q | % | Volume Mixing Ratio scale factor |
As well as axis values, the file contains embedded temperature and VMR profiles represented on the pressure-axis. The temperature profile allows for an alternative interpretation of the temperature axis as relative temperatures applied at each tabulated pressure. The VMR profile is used in conjunction with the VMR scale factor axis to establish actual VMR-axis values at each tabulated pressure.
Such LUTs can be generated using the RFM, and further manipulated with separate specific software.
File Structure | |
---|---|
Header Section | |
!CMNT | (Optional) Comment record(s) |
Format_ID | File format ID record |
Mol_ID NWno Wno1 Wno2 WnoD NPTV NPre NTem NVSF | Molecule ID and dimensions record |
Pre(1) Pre(2) ... | Pressure axis values (multiple records) |
... Pre(NPre) | |
TPr(1) TPr(2) ... | Temperature profile (multiple records) |
... TPr(NPre) | |
VPr(1) VPr(2) ... | VMR profile (multiple records) |
... VPr(NPre) | |
Tem(1) Tem(2) ... | Temperature axis values (multiple records) |
... Tem(NTem) | |
VSF(1) VSF(2) ... | VMR Scale Factor axis values (multiple records) |
... VSF(NVSF) | |
Data Section | |
For i = 1, NWno | |
Wno(i) K(i,1,1,1) K(i,2,1,1) ... | Wavenumber, then NPTV tabulated absorption coefficient (multiple records) |
... K(i,NPre,NTem,NVSF) | |
[eof] |
Field | Type | Description | Units | Range |
---|---|---|---|---|
| C80 | Comment record[1] | ||
| R | File format identifier | 1.0[2] | |
| R | HITRAN molecule ID [.Isotope#] [3] | ≥ 1 | |
| I | No. spectral points/data records in file | ≥ 2 | |
| D | Lowest/First wavenumber in file | cm-1 | 0 – |
| D | Highest/Last wavenumber in file | cm-1 | > |
| D | Wavenumber (minimum) increment [4] | cm-1 | > 0 |
| I | Product of
( | ≥ 1 | |
| I | No. pressure-axis values | ≥ 1 | |
| I | No. temperature-axis values[6] | | | |
| I | No. VSF-axis (q-axis) values | 1 (usually) | |
| R | (NPre) Pressure axis values[7] | hPa | 0 – ∼1000 |
| R | (NPre) Temperature profile values [7] | K | > 0 |
| R | (NPre) VMR profile values [7] | ppmv | 0 – 106 |
| R | (NTem) Temperature axis values [6] | K | > 0 (if Abs) |
| R | (NVSF) VMR scale factor axis values [8] | % | 100.0 expected |
| D | Wavenumber axis value | cm-1 | > 0 |
| R | (NWno,NPTV) ln(k) values, k is absoption coefficient | m2/kmole | ≥ −99[9] |