CLASS4GL has been tested on GNU/Linux environments, including Cent OS and Ubuntu. Although it is not mandatory, a supercomputer environment with qsub functionality Is highly recommended. Other operating systems such as MAC OS X or Windows are not supported yet, but should also work. In case of problems, please contact hendrik.wouters at for support.

STEP 1: install Python 3.X

Most GNU/Linux distributions have Python and Ruby environments pre-installed. Please be sure that it is a Python 3.X environment. Python 2.X environments will not work. Please check your Python version as follows:

python --version

In case you don’t have a Python 3.X environment, you can easily install it with Anaconda, see:

STEP 2: install Python libraries

Before installing CLASS4GL, you need to install its Python dependencies. In case you are using Anaconda-based Python, you can install the dependencies with:

conda install pandas xarray beautifulsoup4 pyyaml netcdf4 seaborn pip ipython
pip install pysolar

STEP 3: install CLASS4GL

Go to (or create) a directory in which you want to install CLASS4GL, for example:

cd mkdir ~/software 
cd software

Get the CLASS4GL package through git and go into the directory:

tar -xzvf class4gl-1.0.0.tar.gz
cd class4gl-1.0.0/class4gl

Set the $CLASS4GL environment variable to the current directory where the CLASS4GL software is installed:


This environmental variable will be used further. You can verify it with:

echo $CLASS4GL

You can always check for a version update of the package at

STEP 4: download the reference data library

In order to be able to run CLASS4GL, you need to install the input reference library. Please download it as follows:

mkdir -p $CLASS4GL_DATA
tar -xzvf GLOBAL_20190115.tar.gz

STEP 5: make environment variables permanent

Make the $CLASS4GL and $CLASS4GL_DATA environment variables permanent by activating it at every time you login to your system or open a terminal:

printf "\n# location of CLASS4GL software\nCLASS4GL='$CLASS4GL'\n" >> $HOME/.bashrc
printf "\n# location of CLASS4GL data library\nCLASS4GL_DATA='$CLASS4GL_DATA'\n" >> $HOME/.bashrc

The environmental variables should be at the bottom of your ~/.bashrc file. You can verify it with:

cat $HOME/.bashrc

You can now run your first experiment by following the steps here.