A Radiative Transfer Python Library (non-scattering)

PyRTlib is a Python package, for non-scattering line-by-line microwave RT simulations. PyRTlib is a user-friendly tool for computing down and up-welling brightness temperatures and related quantities (e.g., atmospheric absorption, optical depth, opacity) in Python.

Plotting of nadir upwelling $\Delta T_b$ using the last two absorption models available in PyRTlib for six reference atmosphere climatology.

Installation

Use pip package to install quicly the pyrtlib library. See installation instructions for more info on how instaling pyrtlib.

   $ pip install pyrtlib

Example

For examples of how to use pyrtlib see the examples gallery. Code can be downloaded both as python script or notebook file.

Performing calculation of upwelling brightness temperature.

   from pyrtlib.tb_spectrum import TbCloudRTE
   from pyrtlib.climatology import AtmosphericProfiles as atmp
   from pyrtlib.utils import mr2rh, ppmv2gkg

Atmospheric profile definition:

   z, p, _, t, md = atmp.gl_atm(atmp.MIDLATITUDE_SUMMER)

Units conversion:

   gkg = ppmv2gkg(md[:, atmp.H2O], atmp.H2O)

Relative humidity of $H_2O$ (water vapor)

   rh = mr2rh(p, t, gkg)[0] / 100

Deifinition of angles and frequencies:

   ang = np.array([90.])
   frq = np.arange(20, 1001, 1)

Initialize parameters for main execution:

   rte = TbCloudRTE(z, p, t, rh, frq, ang)

Set absorption model:

   rte.init_absmdl('R22SD')

Execute model by computing upwelling radiances:

   df = rte.execute()
   df.tbtotal
   0      293.119811
   1      292.538088
   2      291.736672
   3      291.913658
   4      292.493971
            ...    
   976    230.179993
   977    231.435965
   978    232.592915
   979    233.666322
   980    234.667522
   Name: tbtotal, Length: 981, dtype: float64

My first run with PyRTlib

You can get started with PyRTlib by installing and executing the first radiative transfer calculation from the following Colab Notebook

Cite as

Larosa, S., Cimini, D., Gallucci, D., Nilo, S. T., and Romano, F.: PyRTlib: an educational Python-based library for non-scattering atmospheric microwave radiative transfer computations, Geosci. Model Dev., 17, 2053–2076, https://doi.org/10.5194/gmd-17-2053-2024, 2024.

Larosa, S., Cimini, D., Gallucci, D., Nilo, S. T., & Romano, F. (2024). PyRTlib: a python package for non-scattering line-by-line microwave Radiative Transfer simulations. (Computer software). https://doi.org/10.5281/zenodo.8219145

Contributors