RRTMGP uses a k-distribution to provide an optical description (absorption and possibly Rayleigh optical depth) of the gaseous atmosphere, along with the relevant source functions, on a pre-determined spectral grid given temperatures, pressures, and gas concentration. The k-distribution currently distributed with this package is applicable to the Earth's atmosphere under present-day, pre-industrial, and 4xCO2 conditions.
RTE computes fluxes given spectrally-resolved optical descriptions and source functions. The fluxes are normally summarized or reduced via a user extensible class.
Example programs and documenation are evolving - please see examples/ in the repo and Wiki on the project's Github page. Suggestions are welcome. Meanwhile for questions please contact Robert Pincus and Eli Mlawer at email@example.com.
In the most recent revision, the default method for solution for longwave problems that include scattering has been changed from 2-stream methods to a re-scaled and refined no-scattering calculation following Tang et al. 2018.
Building the libraries.
- Set environment variables
FC(the Fortran 2003 compiler) and
FCFLAGS(compiler flags). Alternately create a Makefile.conf that sets these variables. You could also link to an existing file.
- Set environment variable
openaccif you want the OpenACC kernels rather than the default.
Two examples are provided, one for clear skies and one including clouds. See the README file and codes in each directory for further information.