About LOTOS-EUROS

Originally designed to investigate atmospheric ozone circulation, today's LOTOS-EUROS:

• efficiently simulates air quality and deposition on regional and sub-regional scales;
• covers a wide range of inert and chemically active constituents including ozone, NO₂, inorganic and organic PM2.5 and PM10;
• has a long-standing record of data assimilation for satellite data and ground measurements;
• uses a labelling technique for accurate source apportionment;
• benefits from in-house cooperation with emission experts for accurate emission input and modelling;

and provides:

• analyses of concentrations, deposition and related health indicators for assessment studies;
• operational air quality forecasts;
• climate scenarios for the study of air quality and input to integrative climate models.

LOTOS-EUROS calculates the formation and dispersion of ozone, nitrogen dioxide, ammonia, organic and elemental carbon, mineral dust, sea spray, secondary aerosols and heavy metals across Europe. The default model resolution is approximately 25 x 25 km² but it is possible to zoom in on  urban and industrial areas. The model links anthropogenic and biogenic emissions with the occurrence of specific concentrations and deposition. Its vertical layer structure makes it very efficient in use.

LOTOS and EUROS were developed in the 1990s by the Dutch organization for Applied Scientific Research TNO and The Environmental Assessment Agency of the Dutch National Institute for Public Health and the Environment (RIVM/MNP) and have been used as models for the study of the atmospheric distribution of photo-oxidants. The two models were combined in 2004 to give LOTOS-EUROS version 1.0, which has been used by TNO, RIVM and the Royal Dutch Meteorological Institute KNMI. The open-source 2.0 version of the model was released in 2016 to extend the community of users. The current version is version 3.1, which offers expanded capabilities including

• CB7 chemistry scheme. CB4 remains the default, but CB7 adds a much more detailed gas-phase chemistry scheme: 111 species and 230 reactions, compared with 33 species and 104 reactions in the documented CB4 implementation. It improves representation of isoprene, terpenes—including explicit α-pinene—larger alkanes, ketones, organic peroxy radicals and aromatic hydroperoxides. This is intended mainly to improve VOC oxidation and secondary organic aerosol formation.
• Three-tier land use system. Land characterization is now separated into climate zone, land-use class and vegetation type. This allows, for example, the same vegetation type to have different parameters in different climates and different crops to have distinct properties.
  As a consequence, dry-deposition parameters are no longer hard-coded. They are supplied through a separate parameter file, allowing users to define or extend land-use and vegetation classes—and their deposition properties—without modifying the model source code.