To calculate integrated shortwave or longwave irradiance, or to simulate satellite instrument channels, use
   correlated_k type
to choose between the following types of correlated-k schemes:
kato
Kato et al. (1999) correlated-k distribution, shortwave; based on HITRAN 96. Please note that the bands above 2.5 micrometer are not very reliable which, however, this has only little impact on integrated shortwave radiation.
kato2
Kato et al. (1999), shortwave; optimized version (Seiji Kato, personal communication, 2003); please note that kato2 only has 148 subbands (that is, calls to the rte_solver) compared to 575 for kato which translates to a decrease in computational speed by up to a factor of 4 with only little increase in uncertainty. The absorption data are based on HITRAN 2000. Please note that the bands above 2.5 micrometer are not very reliable which, however, this has only little impact on integrated shortwave radiation.
kato2.96
Kato et al. (1999), shortwave; optimized version (Seiji Kato, personal communication, 2003); similar to kato2 but based on HITRAN96. Please note that the bands above 2.5 micrometer are not very reliable which, however, has only little impact on integrated shortwave radiation.
fu
Fu and Liou (1993); Fu and Liou (1992), shortwave and longwave; fast parameterization, developed for climate models.
avhrr_kratz
Kratz and Varanasi (1995), AVHRR instrument channels
lowtran
Gas absorption parameterization from LOWTRAN; code adopted from SBDART (Ricchiazzi et al., 1998); please see the section on "Spectral resolution".
sbdart
Identical to LOWTRAN.
If correlated_k kato/kato2/kato2.96/fu/avhrr_kratz is specified, the extraterrestrial flux is taken from internally defined files specific for each parameterization, not from solar_file. The output is the integrated irradiance for each band. To get e.g. integrated shortwave irradiance, simply add all bands of the Kato et al. (1999) or the Fu and Liou (1993); Fu and Liou (1992) parameterization. The five AVHRR channels are weighted sums of the libRadtran output. Examples how to integrate the output in the avhrr_kratz case are included in the uvspec self check which is initiated with make check.





Arve Kylling 2010-03-10