irradpy: Python package for MERRA-2 download, extraction and usage for clear-sky irradiance modelling

Abstract

Clear-sky irradiance modelling requires many input variables to access the best available methodologies in literature. It is the authors’ experience that there are unnecessary computational barriers to obtaining and using the data needed for worldwide clear-sky modelling. For this reason, we present a data article introducing a new Python package called irradpy that, in this first release, (i) downloads the specific variables required for worldwide clear-sky irradiance modelling from the MERRA-2 reanalysis database and reorganises them for optimised usage, (ii) provides two functions for the world leading global horizontal irradiance clear-sky models (MAC2 and REST2v5) to make use of the downloaded MERRA-2 reanalysis database, (iii) provides an example script showing how it works and can be used. The package is available through the Python Package Index (PyPi) and can also be found in the GitHub repository at https://github.com/BXYMartin/Python-irradpy.