Open-source version

Why open source?

It is our belief that a model is improved when more people use and develop it. In line with this vision, LOTOS-EUROS has been made available without charge in an open-source version.

This open-source version is based on LOTOS-EUROS v2.0 and contains all functionality described in the v2.0 Reference Guide. Additional functionality can be added in consultation with TNO.


The first international user workshop on the open source version of LOTOS-EUROS was held at TNO Utrecht on 18 January 2018.

The second international user workshop will be held at TNO Utrecht on 17 January 2019. A training course for new users will be given in the days preceding the workshop (14-16 January 2019)

For more information: contact

Computing environment

Please note that LOTOS-EUROS is written in Fortran and is designed for Unix/Linux platforms, with Python scripts to handle compilation. Input and output data take up considerable space.

Input data

The open-source version does not include meteorological fields to drive the model, but does provide static input (emissions and time profiles, land use and climatological boundary conditions).

The latest set of emission data for Europe developed by TNO for use in the EU MACC (Monitoring Atmospheric Composition and Climate) project can be made available in various forms on request. These data can be requested using the application form on the MACC website.

Community portal

The use of the LOTOS-EUROS open-source version is regulated by means of a community site.

Logging on to the community site gives access to the source code, a test bed with input data and verification output, a wiki and a user forum. Alerts can be sent when model updates are available.

To gain access to the community site you must accept the conditions under which the code is made available using the form given below.

Agreement Form

By providing the information requested on the agreement form and using the LOTOS-EUROS open source version, you indicate your acceptance of the LOTOS-EUROS open source license agreement. After receiving your information, TNO will proceed to grant you access to the model community site and inform you when you have been added to the system.

Go to the form