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                               JURASSIC
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Introduction
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The Juelich Rapid Spectral Simulation Code (JURASSIC) is a fast
radiative transfer model for the mid-infrared spectral region
developed at the Juelich Supercomputing Centre, Germany.

JURASSIC has been developed to support the analysis of atmospheric
remote sensing measurements. The model has been used to retrieve
geophysical data such as pressure, temperature, and trace gas
concentrations from ESA and NASA satellite measurements and
observations of local aircraft experiments.


Algorithms
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JURASSIC uses computationally efficient methods for the radiative
transfer calculations. Radiative transfer calculations are based on
the Curtis-Godson Approximation (CGA) and the Emissivity Growth
Approximation (EGA). Band transmittances are obtained from
pre-calculated look-up tables from line-by-line reference model
calculations.

JURASSIC features a 3-D raytracer to realize different observation
geometries and to enable tomographic studies. JURASSIC has also been
extended to perform Mie-scattering calculations for aerosol and ice
particles. The model was carefully tested in intercomparisons with
the Karlsruhe Optimized and Precise Radiative Transfer Algorithm
(KOPRA) and the Oxford Reference Forward Model (RFM).


Implementation
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JURASSIC is written in the C programming language and consists of
about 10,000 lines of code. It uses the GNU Scientific Library (GSL)
for numerical operations. JURASSIC can be used on a desktop PC, but
it also features an MPI/OpenMP hybrid-parallelization for efficient
use on supercomputers.


Contact
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We are interested in sharing JURASSIC for research applications.
JURASSIC is distributed under the GNU GPL v3.

Please contact us for further details.