- The following text is adapted from libRadtran site -
The libRadtran (Emde et al., 2016) (Mayer et al., 2005) (library for radiative transfer) is a collection of C and Fortran functions and programs for calculation of solar and thermal radiation in the Earth's atmosphere. The central programo of the libRadtran package is the radiative transfer tool uvspec. uvspec was originally designed to calculate spectral irradiance and actinic flux in the ultraviolet and visible parts of the spectrum. Over the years, uvspec has undergone numerous extensions and improvements. uvspec now includes the full solar and thermal spectrum, currently from 120 nm to 100μm. Libradtran has been designed as a user-friendly and versatile tool which provides a variety of options to setup and modify an atmosphere with molecules, aerosol particles, water and ice clouds, and a surface as lower boundary. One of the unique features of libRadtran is that it includes not only one but a selection of about ten different radiative transfer equation solvers, fully transparent to the user, including the widely-used DISORT code by (Stamnes et al., 1988), a fast two-stream code (Kylling et al., 1995), a polarization-dependent code polRadtran (Evans and Stephens, 1991), and the fully three-dimensional Monte Carlo code for the physically correct tracing of photons in cloudy atmospheres, MYSTIC (Emde et al., 2011). MYSTIC optionally allows to consider polarization and fully spherical geometry. Please note that the public release includes only a 1D version of MYSTIC.
LibRadtran was developed and continues to be maintained by the Meteorological Institude of Munich and it is freely available under the GNU General Public License.
The underlying physics and algorithms used in libRadtran are well established for more than 30 years.
For additional information about libRadtran, please contact the developers of the sofware package.
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Kylling, A., Stamnes, K., & Tsay, S.-C., (1995), "A reliable and efficient two–stream algorithm for spherical radiative transfer: documentation of accuracy in realistic layered media." Journal of Atmospheric Chemistry. Vol. 21, pp. 115‒ 150.
Evans, K.F., & Stephens, G.L. (1991), "A new polarized atmospheric radiative transfer model." J. Quant. Spectrosc. Radiat. Transfer, Vol. 46, pp. 413‒ 423.
Mayer, B., & Kylling, A. (2005), "Technical note: The libRadtran software package for radiative transfer calculations - description and examples of use." Atmos. Chem. Phys., Vol. 5, pp. 1855‒ 1877.
Emde, C., Buras, R., & Mayer, B. (2011), "ALIS: An efficient method to compute high spectral resolution polarized solar radiances using the Monte Carlo approach." J. Quant. Spectrosc. Radiat. Transfer. Vol. 112, pp. 1622‒ 1631.
Emde, C., Buras-Schnell, A., Kylling, B., Mayer, B., Gasteiger, U., Hamann, U., Kylling, J., Richter, B., Pause, C., Dowling, T., & Bugliaro, L. (2016), "The libradtran software package for radiative transfer calculations (version 2.0.1)." Geoscientific Model Development. Vol. 9, No. 5, pp. 1647‒ 1672.