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Air pollution models

Information on models developed by us:


THOR is an air pollution forecast system consisting of several air pollution models and a weather forecast model. This system of models is used to produce operational 3-day air pollution forecasts, four times every day.


Human Exposure Modelling to Traffic Air Pollution. DEHM/UBM/AirGIS is aGIS-based human exposure modelling system for traffic air pollution for application in air pollution epidemiological studies, human exposure studies, as well as urban air quality assessment and management. The recently added "DEHM/UBM" in the beginng of the name indicates the close coupling with the regional DEHM model and the Urban Background Model (UBM) providing background concentration and meteorology as input.


Atmospheric dispersion model. OML is an operational short-range model for regulatory applications.



OML-Highway is a GIS-based model for assessment of air quality along motorways and other main roads in open terrain. 


OSPM (Operational Street Pollution Model) is a street canyon model. It can be used to assess pollution resulting from traffic in streets.



"Danish Eulerian Model" is a large (computer intensive) air pollution model for studying various phenomena connected with transport of air pollutants in the atmosphere. The space domain of the model comprises all of Europe. 

DEHM (in Danish)

DEHM – the Danish Eulerian Hemispheric Model - is a state-of-the-art dispersion model. It is used, i.a. within the Danish national environmental monitoring programme NOVANA for assessment of nitrogen deposition, for assessments of air pollution transport to the Arctic. It also forms a component within the THOR system for air pollution prognoses at a European scale.


"Danish Rimpuff and Eulerian Accidental release Model" is a comprehensive, three-dimensional tracer model,

which has been developed for studying transport, dispersion, and deposition of air pollution caused by a single

but strong source, as e.g., the Chernobyl accident.


ACDEP is a variable scale Lagrangian model. The model has been used for computing nitrogen deposition to Danish marine waters, and to assess the contribution to the deposition from various source areas and source types. The model contains a detailed chemical mechanism with 37 species and 80 reactions.

Until 2004 results from ACDEP were used for assessments within the Danish national environmental programmes, but ACDEP has now been replaced by DEHM in this context.

Deposition calculations  (in Danish)

DEHM is used for routine computations of deposition of nitrogen and sulphur in Denmark. Computations with a high resolution are performed for selected areas in Denmark using OML-DEP - a variant of the OML model.

COPREM - a receptor model

COPREM (COnstrained Physical REceptor Model) is a receptor model that can be used for source apportionment. It unifies qualities from factor analytic models and chemical mass balance models.