RFM Flags

RJT Flag: Write Rayleigh-Jeans Temperature Spectra

30MAY18

Enabled
Create .rjt files containing Rayleigh-Jeans temperature spectra, i.e. the temperature [K] of the Planck Function that gives the equivalent spectral radiance in the long wavelength regime.
If *RJT section in Driver Table, read user-defined filename.

Disabled
No Rayleigh-Jeans temperature spectra written
*RJT section ignored.

Restrictions
Incompatible with TAB Flag.

Notes
  1. Internally the RFM calculates radiance, these are converted to Rayleigh-Jeans temperature TRJ [K] at the output stage (subroutine wrtout.for, spcout_sub.f90 in RFM v5) using the formula
    TRJ = c2 R / ( c1 ν2)
    where c1,c2 are the radiation constants, approx 1.191E-3 nW/(cm2 sr (cm-1)4) and 1.439 K/cm-1 respectively (actual values in phycon.inc, phycon_dat.f90 in RFM v5), ν is the wavenumber [cm-1], R is the radiance [nW/(cm2 sr cm-1)].
  2. The Rayleigh-Jeans Temperature is the approximation to the Brightness Temperature calculation assuming that c1 ν3 / R ≪ 1, i.e., using the Rayleigh-Jeans approximation that Temperature and Radiance are linearly related (suitable for microwave region).
  3. See RFM Outputs for default filename(s).

Bugs
[none reported]